[PATCH 0/8] Make SCMI transport as standalone drivers

[PATCH 0/8] Make SCMI transport as standalone drivers

[Cristian Marussi]

Hi all,

Till now the SCMI transport layer was being built embedded into in the core
SCMI stack.

Some of these transports, despite being currently part of the main SCMI
module, are indeed also registered with different subsystems like optee or
virtio, and actively probed also by those: this led to a few awkward and
convoluted tricks to properly handle such interactions at boot time in the
SCMI stack.

Moreover some partner expressed the desire to be able to fully modularize
the transports components.

This series aim to make all such transports as standalone drivers that can
be optionally loaded as modules.

In order to do this, at first some new mechanism is introduced to support
this new capability while maintaining, in parallel, the old legacy embedded
transports; then each transport, one by one, is transitioned to be a
standalone driver and finally the old legacy support for embedded transport
is removed.

Patch [1/8] is a mostly unrelated (but much needed) clean-up from Peng,
which I included in this series to avoid conflicts at merge.

Patch [2/8] simply collects the existing datagram manipulation helpers in a
pair of function pointers structures, in preparation for later reworks.

Patch [3/8] adds the bulk of the new logic to the core SCMI stack and then
each existing transport is transitioned to be a standalone driver in
patches 4,5,6,7 while shuffling around the compatibles. (no DT change is
needed of curse for backward compatibility)
While doing this I kept the module authorship in line with the main
author(S) as spitted out by git-blame.

Finally patch [8/8] removes all the legacy dead code from the core SCMI
stack.

No new symbol EXPORT has been added.

The new transport drivers have been tested, as built-in and LKM, as
follows:

- mailbox on JUNO
- virtio on emulation
- optee on QEMU/optee using Linaro setup

Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
testing commands, replies, delayed responses and notification.

Multiple virtual SCMI instances support has been tested too.

SMC has NOT been tested/exercised at run-time, only compile-tested.
(due to lack of hardware)

Note that in this new setup, all the probe deferral and retries between the
SCMI core stack and the transports has been removed, since no more needed.

Moreover the new drivers have been tested also with a fully modularized
SCMI stack, i.e.:

  scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor modules ]

ToBeDone:
 - completely remove any dependency at build time at the Kconfig level between
   the SCMI core and the transport drivers: so that the transports will be
   dependent only on the related subsystems (optee/virtio/mailbox/smc)
   (easy to be done but maybe it is not worth...)
 - integrate per-platform transport configuration capabilities
   (max_rx_timeout_ms & friends..)

Based on sudeep/for-next/scmi/updates.

Any feedback, and especially testing (:D) is welcome.

Thanks,
Cristian

---
v1 --> v2
- fixed setup_shmem_iomap to address also SMC needs (QC/nikunj)
  (silencing also warnings by kernel test robot <lkp@intel.com>)
- using __free OF cleanup.h magic in setup_shmme_iomap
- properly handle platform_driver_register() failures (Dan)
- fixed a few commit message style
- added a few missing static in scmi_desc
  (addresses warnings by kernel test robot <lkp@intel.com>)

Cristian Marussi (7):
  firmware: arm_scmi: Introduce packet handling helpers
  firmware: arm_scmi: Add support for standalone transport drivers
  firmware: arm_scmi: Make MBOX transport a standalone driver
  firmware: arm_scmi: Make SMC transport a standalone driver
  firmware: arm_scmi: Make OPTEE transport a standalone driver
  firmware: arm_scmi: Make VirtIO transport a standalone driver
  firmware: arm_scmi: Remove legacy transport-layer code

Peng Fan (1):
  firmware: arm_scmi: Introduce setup_shmem_iomap

 drivers/firmware/arm_scmi/Kconfig             |  20 +-
 drivers/firmware/arm_scmi/Makefile            |   9 +-
 drivers/firmware/arm_scmi/common.h            | 184 +++++++++++++-----
 drivers/firmware/arm_scmi/driver.c            | 140 +++++--------
 drivers/firmware/arm_scmi/msg.c               |  34 +++-
 .../{mailbox.c => scmi_transport_mailbox.c}   |  69 ++++---
 .../{optee.c => scmi_transport_optee.c}       | 124 +++++-------
 .../arm_scmi/{smc.c => scmi_transport_smc.c}  |  58 +++---
 .../{virtio.c => scmi_transport_virtio.c}     | 103 +++++-----
 drivers/firmware/arm_scmi/shmem.c             |  85 ++++++--
 10 files changed, 468 insertions(+), 358 deletions(-)
 rename drivers/firmware/arm_scmi/{mailbox.c => scmi_transport_mailbox.c} (87%)
 rename drivers/firmware/arm_scmi/{optee.c => scmi_transport_optee.c} (89%)
 rename drivers/firmware/arm_scmi/{smc.c => scmi_transport_smc.c} (87%)
 rename drivers/firmware/arm_scmi/{virtio.c => scmi_transport_virtio.c} (94%)

-- 
2.45.2

[PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap

[Cristian Marussi]

From: Peng Fan <peng.fan@nxp.com>

To get the address of shmem could be generalized by introducing
setup_shmem_iomap. Then the duplicated code in mailbox.c, optee.c
and smc.c could be dropped.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
[ Cristian: use OF __free and make use of the new helper also in smc.c ]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
- add optional *res param to setup_shmem_iomap
- fixed __iomem tagging
- use OF __free cleanup.h magic to of_put()
---
 drivers/firmware/arm_scmi/common.h  |  2 ++
 drivers/firmware/arm_scmi/mailbox.c | 27 +++----------------
 drivers/firmware/arm_scmi/optee.c   | 35 +++---------------------
 drivers/firmware/arm_scmi/shmem.c   | 41 +++++++++++++++++++++++++++++
 drivers/firmware/arm_scmi/smc.c     | 27 ++++---------------
 5 files changed, 56 insertions(+), 76 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 4b8c5250cdb5..d5e80a24e2d4 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -327,6 +327,8 @@ bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
 		     struct scmi_xfer *xfer);
 bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem);
 bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem);
+void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo, struct device *dev,
+				bool tx, struct resource *res);
 
 /* declarations for message passing transports */
 struct scmi_msg_payld;
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 0219a12e3209..886fc4eedb4a 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -178,11 +178,8 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	const char *desc = tx ? "Tx" : "Rx";
 	struct device *cdev = cinfo->dev;
 	struct scmi_mailbox *smbox;
-	struct device_node *shmem;
-	int ret, a2p_rx_chan, p2a_chan, p2a_rx_chan, idx = tx ? 0 : 1;
+	int ret, a2p_rx_chan, p2a_chan, p2a_rx_chan;
 	struct mbox_client *cl;
-	resource_size_t size;
-	struct resource res;
 
 	ret = mailbox_chan_validate(cdev, &a2p_rx_chan, &p2a_chan, &p2a_rx_chan);
 	if (ret)
@@ -195,25 +192,9 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!smbox)
 		return -ENOMEM;
 
-	shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
-	if (!of_device_is_compatible(shmem, "arm,scmi-shmem")) {
-		of_node_put(shmem);
-		return -ENXIO;
-	}
-
-	ret = of_address_to_resource(shmem, 0, &res);
-	of_node_put(shmem);
-	if (ret) {
-		dev_err(cdev, "failed to get SCMI %s shared memory\n", desc);
-		return ret;
-	}
-
-	size = resource_size(&res);
-	smbox->shmem = devm_ioremap(dev, res.start, size);
-	if (!smbox->shmem) {
-		dev_err(dev, "failed to ioremap SCMI %s shared memory\n", desc);
-		return -EADDRNOTAVAIL;
-	}
+	smbox->shmem = setup_shmem_iomap(cinfo, dev, tx, NULL);
+	if (IS_ERR(smbox->shmem))
+		return PTR_ERR(smbox->shmem);
 
 	cl = &smbox->cl;
 	cl->dev = cdev;
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index 4e7944b91e38..d9458ef7378a 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -368,38 +368,11 @@ static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *ch
 static int setup_static_shmem(struct device *dev, struct scmi_chan_info *cinfo,
 			      struct scmi_optee_channel *channel)
 {
-	struct device_node *np;
-	resource_size_t size;
-	struct resource res;
-	int ret;
-
-	np = of_parse_phandle(cinfo->dev->of_node, "shmem", 0);
-	if (!of_device_is_compatible(np, "arm,scmi-shmem")) {
-		ret = -ENXIO;
-		goto out;
-	}
-
-	ret = of_address_to_resource(np, 0, &res);
-	if (ret) {
-		dev_err(dev, "Failed to get SCMI Tx shared memory\n");
-		goto out;
-	}
-
-	size = resource_size(&res);
+	channel->req.shmem = setup_shmem_iomap(cinfo, dev, true, NULL);
+	if (IS_ERR(channel->req.shmem))
+		return PTR_ERR(channel->req.shmem);
 
-	channel->req.shmem = devm_ioremap(dev, res.start, size);
-	if (!channel->req.shmem) {
-		dev_err(dev, "Failed to ioremap SCMI Tx shared memory\n");
-		ret = -EADDRNOTAVAIL;
-		goto out;
-	}
-
-	ret = 0;
-
-out:
-	of_node_put(np);
-
-	return ret;
+	return 0;
 }
 
 static int setup_shmem(struct device *dev, struct scmi_chan_info *cinfo,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index b74e5a740f2c..06f68ee0e9f8 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -7,6 +7,8 @@
 
 #include <linux/ktime.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/processor.h>
 #include <linux/types.h>
 
@@ -133,3 +135,42 @@ bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
 {
 	return ioread32(&shmem->flags) & SCMI_SHMEM_FLAG_INTR_ENABLED;
 }
+
+void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
+				struct device *dev, bool tx,
+				struct resource *res)
+{
+	struct device_node *shmem __free(device_node);
+	const char *desc = tx ? "Tx" : "Rx";
+	int ret, idx = tx ? 0 : 1;
+	struct device *cdev = cinfo->dev;
+	struct resource lres = {};
+	resource_size_t size;
+	void __iomem *addr;
+
+	shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
+	if (!shmem)
+		return ERR_PTR(-ENODEV);
+
+	if (!of_device_is_compatible(shmem, "arm,scmi-shmem"))
+		return ERR_PTR(-ENXIO);
+
+	/* Use a local on-stack as a working area when not provided */
+	if (!res)
+		res = &lres;
+
+	ret = of_address_to_resource(shmem, 0, res);
+	if (ret) {
+		dev_err(cdev, "failed to get SCMI %s shared memory\n", desc);
+		return ERR_PTR(ret);
+	}
+
+	size = resource_size(res);
+	addr = devm_ioremap(dev, res->start, size);
+	if (!addr) {
+		dev_err(dev, "failed to ioremap SCMI %s shared memory\n", desc);
+		return ERR_PTR(-EADDRNOTAVAIL);
+	}
+
+	return addr;
+}
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index 39936e1dd30e..59b6c04b52bc 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -130,9 +130,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	struct device *cdev = cinfo->dev;
 	unsigned long cap_id = ULONG_MAX;
 	struct scmi_smc *scmi_info;
-	resource_size_t size;
-	struct resource res;
-	struct device_node *np;
+	struct resource res = {};
 	u32 func_id;
 	int ret;
 
@@ -143,31 +141,16 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!scmi_info)
 		return -ENOMEM;
 
-	np = of_parse_phandle(cdev->of_node, "shmem", 0);
-	if (!of_device_is_compatible(np, "arm,scmi-shmem")) {
-		of_node_put(np);
-		return -ENXIO;
-	}
-
-	ret = of_address_to_resource(np, 0, &res);
-	of_node_put(np);
-	if (ret) {
-		dev_err(cdev, "failed to get SCMI Tx shared memory\n");
-		return ret;
-	}
-
-	size = resource_size(&res);
-	scmi_info->shmem = devm_ioremap(dev, res.start, size);
-	if (!scmi_info->shmem) {
-		dev_err(dev, "failed to ioremap SCMI Tx shared memory\n");
-		return -EADDRNOTAVAIL;
-	}
+	scmi_info->shmem = setup_shmem_iomap(cinfo, dev, tx, &res);
+	if (IS_ERR(scmi_info->shmem))
+		return PTR_ERR(scmi_info->shmem);
 
 	ret = of_property_read_u32(dev->of_node, "arm,smc-id", &func_id);
 	if (ret < 0)
 		return ret;
 
 	if (of_device_is_compatible(dev->of_node, "qcom,scmi-smc")) {
+		resource_size_t size = resource_size(&res);
 		void __iomem *ptr = (void __iomem *)scmi_info->shmem + size - 8;
 		/* The capability-id is kept in last 8 bytes of shmem.
 		 *     +-------+ <-- 0
-- 
2.45.2

[PATCH v2 2/8] firmware: arm_scmi: Introduce packet handling helpers

[Cristian Marussi]

Introduce a pair of structures initialized to contain all the existing
packet handling helpers, both for transports based on shared memory
and messages.

No functional change.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
- fixed commit message
---
 drivers/firmware/arm_scmi/common.h  | 78 +++++++++++++++++++++--------
 drivers/firmware/arm_scmi/mailbox.c | 20 ++++----
 drivers/firmware/arm_scmi/msg.c     | 29 +++++++----
 drivers/firmware/arm_scmi/optee.c   | 14 +++---
 drivers/firmware/arm_scmi/shmem.c   | 45 +++++++++++------
 drivers/firmware/arm_scmi/smc.c     |  8 +--
 drivers/firmware/arm_scmi/virtio.c  | 14 +++---
 7 files changed, 132 insertions(+), 76 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index d5e80a24e2d4..8e5751aaa600 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -4,7 +4,7 @@
  * driver common header file containing some definitions, structures
  * and function prototypes used in all the different SCMI protocols.
  *
- * Copyright (C) 2018-2022 ARM Ltd.
+ * Copyright (C) 2018-2024 ARM Ltd.
  */
 #ifndef _SCMI_COMMON_H
 #define _SCMI_COMMON_H
@@ -315,20 +315,39 @@ void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
 /* shmem related declarations */
 struct scmi_shared_mem;
 
-void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
-		      struct scmi_xfer *xfer, struct scmi_chan_info *cinfo);
-u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem);
-void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
+/**
+ * struct scmi_shared_mem_operations  - Transport core operations for
+ * Shared Memory
+ *
+ * @tx_prepare: Prepare the @xfer message for transmission on the chosen @shmem
+ * @read_header: Read header of the message currently hold in @shmem
+ * @fetch_response: Copy the message response from @shmem into @xfer
+ * @fetch_notification: Copy the message notification from @shmem into @xfer
+ * @clear_channel: Clear the @shmem channel busy flag
+ * @poll_done: Check if poll has completed for @xfer on @shmem
+ * @channel_free: Check if @shmem channel is marked as free
+ * @channel_intr_enabled: Check is @shmem channel has requested a completion irq
+ * @setup_iomap: Setup IO shared memory for channel @cinfo
+ */
+struct scmi_shared_mem_operations {
+	void (*tx_prepare)(struct scmi_shared_mem __iomem *shmem,
+			   struct scmi_xfer *xfer,
+			   struct scmi_chan_info *cinfo);
+	u32 (*read_header)(struct scmi_shared_mem __iomem *shmem);
+
+	void (*fetch_response)(struct scmi_shared_mem __iomem *shmem,
+			       struct scmi_xfer *xfer);
+	void (*fetch_notification)(struct scmi_shared_mem __iomem *shmem,
+				   size_t max_len, struct scmi_xfer *xfer);
+	void (*clear_channel)(struct scmi_shared_mem __iomem *shmem);
+	bool (*poll_done)(struct scmi_shared_mem __iomem *shmem,
 			  struct scmi_xfer *xfer);
-void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
-			      size_t max_len, struct scmi_xfer *xfer);
-void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem);
-bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
-		     struct scmi_xfer *xfer);
-bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem);
-bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem);
-void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo, struct device *dev,
-				bool tx, struct resource *res);
+	bool (*channel_free)(struct scmi_shared_mem __iomem *shmem);
+	bool (*channel_intr_enabled)(struct scmi_shared_mem __iomem *shmem);
+	void __iomem *(*setup_iomap)(struct scmi_chan_info *cinfo,
+				     struct device *dev,
+				     bool tx, struct resource *res);
+};
 
 /* declarations for message passing transports */
 struct scmi_msg_payld;
@@ -336,14 +355,29 @@ struct scmi_msg_payld;
 /* Maximum overhead of message w.r.t. struct scmi_desc.max_msg_size */
 #define SCMI_MSG_MAX_PROT_OVERHEAD (2 * sizeof(__le32))
 
-size_t msg_response_size(struct scmi_xfer *xfer);
-size_t msg_command_size(struct scmi_xfer *xfer);
-void msg_tx_prepare(struct scmi_msg_payld *msg, struct scmi_xfer *xfer);
-u32 msg_read_header(struct scmi_msg_payld *msg);
-void msg_fetch_response(struct scmi_msg_payld *msg, size_t len,
-			struct scmi_xfer *xfer);
-void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
-			    size_t max_len, struct scmi_xfer *xfer);
+/**
+ * struct scmi_message_operations  - Transport core operations for Message
+ *
+ * @response_size: Get calculated response size for @xfer
+ * @command_size: Get calculated command size for @xfer
+ * @tx_prepare: Prepare the @xfer message for transmission on the provided @msg
+ * @read_header: Read header of the message currently hold in @msg
+ * @fetch_response: Copy the message response from @msg into @xfer
+ * @fetch_notification: Copy the message notification from @msg into @xfer
+ */
+struct scmi_message_operations {
+	size_t (*response_size)(struct scmi_xfer *xfer);
+	size_t (*command_size)(struct scmi_xfer *xfer);
+	void (*tx_prepare)(struct scmi_msg_payld *msg, struct scmi_xfer *xfer);
+	u32 (*read_header)(struct scmi_msg_payld *msg);
+	void (*fetch_response)(struct scmi_msg_payld *msg, size_t len,
+			       struct scmi_xfer *xfer);
+	void (*fetch_notification)(struct scmi_msg_payld *msg, size_t len,
+				   size_t max_len, struct scmi_xfer *xfer);
+};
+
+extern const struct scmi_shared_mem_operations scmi_shmem_ops;
+extern const struct scmi_message_operations scmi_msg_ops;
 
 void scmi_notification_instance_data_set(const struct scmi_handle *handle,
 					 void *priv);
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 886fc4eedb4a..60698efe8442 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -40,7 +40,7 @@ static void tx_prepare(struct mbox_client *cl, void *m)
 {
 	struct scmi_mailbox *smbox = client_to_scmi_mailbox(cl);
 
-	shmem_tx_prepare(smbox->shmem, m, smbox->cinfo);
+	scmi_shmem_ops.tx_prepare(smbox->shmem, m, smbox->cinfo);
 }
 
 static void rx_callback(struct mbox_client *cl, void *m)
@@ -56,15 +56,15 @@ static void rx_callback(struct mbox_client *cl, void *m)
 	 * a previous timed-out reply which arrived late could be wrongly
 	 * associated with the next pending transaction.
 	 */
-	if (cl->knows_txdone && !shmem_channel_free(smbox->shmem)) {
+	if (cl->knows_txdone && !scmi_shmem_ops.channel_free(smbox->shmem)) {
 		dev_warn(smbox->cinfo->dev, "Ignoring spurious A2P IRQ !\n");
 		scmi_bad_message_trace(smbox->cinfo,
-				       shmem_read_header(smbox->shmem),
+				       scmi_shmem_ops.read_header(smbox->shmem),
 				       MSG_MBOX_SPURIOUS);
 		return;
 	}
 
-	scmi_rx_callback(smbox->cinfo, shmem_read_header(smbox->shmem), NULL);
+	scmi_rx_callback(smbox->cinfo, scmi_shmem_ops.read_header(smbox->shmem), NULL);
 }
 
 static bool mailbox_chan_available(struct device_node *of_node, int idx)
@@ -192,7 +192,7 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!smbox)
 		return -ENOMEM;
 
-	smbox->shmem = setup_shmem_iomap(cinfo, dev, tx, NULL);
+	smbox->shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, tx, NULL);
 	if (IS_ERR(smbox->shmem))
 		return PTR_ERR(smbox->shmem);
 
@@ -293,7 +293,7 @@ static void mailbox_fetch_response(struct scmi_chan_info *cinfo,
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	shmem_fetch_response(smbox->shmem, xfer);
+	scmi_shmem_ops.fetch_response(smbox->shmem, xfer);
 }
 
 static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
@@ -301,7 +301,7 @@ static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	shmem_fetch_notification(smbox->shmem, max_len, xfer);
+	scmi_shmem_ops.fetch_notification(smbox->shmem, max_len, xfer);
 }
 
 static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
@@ -310,9 +310,9 @@ static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
 	struct mbox_chan *intr_chan;
 	int ret;
 
-	shmem_clear_channel(smbox->shmem);
+	scmi_shmem_ops.clear_channel(smbox->shmem);
 
-	if (!shmem_channel_intr_enabled(smbox->shmem))
+	if (!scmi_shmem_ops.channel_intr_enabled(smbox->shmem))
 		return;
 
 	if (smbox->chan_platform_receiver)
@@ -335,7 +335,7 @@ mailbox_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	return shmem_poll_done(smbox->shmem, xfer);
+	return scmi_shmem_ops.poll_done(smbox->shmem, xfer);
 }
 
 static const struct scmi_transport_ops scmi_mailbox_ops = {
diff --git a/drivers/firmware/arm_scmi/msg.c b/drivers/firmware/arm_scmi/msg.c
index d33a704e5814..f4ba38afe0bb 100644
--- a/drivers/firmware/arm_scmi/msg.c
+++ b/drivers/firmware/arm_scmi/msg.c
@@ -4,8 +4,8 @@
  *
  * Derived from shm.c.
  *
- * Copyright (C) 2019-2021 ARM Ltd.
- * Copyright (C) 2020-2021 OpenSynergy GmbH
+ * Copyright (C) 2019-2024 ARM Ltd.
+ * Copyright (C) 2020-2024 OpenSynergy GmbH
  */
 
 #include <linux/types.h>
@@ -30,7 +30,7 @@ struct scmi_msg_payld {
  *
  * Return: transport SDU size.
  */
-size_t msg_command_size(struct scmi_xfer *xfer)
+static size_t msg_command_size(struct scmi_xfer *xfer)
 {
 	return sizeof(struct scmi_msg_payld) + xfer->tx.len;
 }
@@ -42,7 +42,7 @@ size_t msg_command_size(struct scmi_xfer *xfer)
  *
  * Return: transport SDU size.
  */
-size_t msg_response_size(struct scmi_xfer *xfer)
+static size_t msg_response_size(struct scmi_xfer *xfer)
 {
 	return sizeof(struct scmi_msg_payld) + sizeof(__le32) + xfer->rx.len;
 }
@@ -53,7 +53,7 @@ size_t msg_response_size(struct scmi_xfer *xfer)
  * @msg: transport SDU for command
  * @xfer: message which is being sent
  */
-void msg_tx_prepare(struct scmi_msg_payld *msg, struct scmi_xfer *xfer)
+static void msg_tx_prepare(struct scmi_msg_payld *msg, struct scmi_xfer *xfer)
 {
 	msg->msg_header = cpu_to_le32(pack_scmi_header(&xfer->hdr));
 	if (xfer->tx.buf)
@@ -67,7 +67,7 @@ void msg_tx_prepare(struct scmi_msg_payld *msg, struct scmi_xfer *xfer)
  *
  * Return: SCMI header
  */
-u32 msg_read_header(struct scmi_msg_payld *msg)
+static u32 msg_read_header(struct scmi_msg_payld *msg)
 {
 	return le32_to_cpu(msg->msg_header);
 }
@@ -79,8 +79,8 @@ u32 msg_read_header(struct scmi_msg_payld *msg)
  * @len: transport SDU size
  * @xfer: message being responded to
  */
-void msg_fetch_response(struct scmi_msg_payld *msg, size_t len,
-			struct scmi_xfer *xfer)
+static void msg_fetch_response(struct scmi_msg_payld *msg,
+			       size_t len, struct scmi_xfer *xfer)
 {
 	size_t prefix_len = sizeof(*msg) + sizeof(msg->msg_payload[0]);
 
@@ -100,8 +100,8 @@ void msg_fetch_response(struct scmi_msg_payld *msg, size_t len,
  * @max_len: maximum SCMI payload size to fetch
  * @xfer: notification message
  */
-void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
-			    size_t max_len, struct scmi_xfer *xfer)
+static void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
+				   size_t max_len, struct scmi_xfer *xfer)
 {
 	xfer->rx.len = min_t(size_t, max_len,
 			     len >= sizeof(*msg) ? len - sizeof(*msg) : 0);
@@ -109,3 +109,12 @@ void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
 	/* Take a copy to the rx buffer.. */
 	memcpy(xfer->rx.buf, msg->msg_payload, xfer->rx.len);
 }
+
+const struct scmi_message_operations scmi_msg_ops = {
+	.tx_prepare = msg_tx_prepare,
+	.command_size = msg_command_size,
+	.response_size = msg_response_size,
+	.read_header = msg_read_header,
+	.fetch_response = msg_fetch_response,
+	.fetch_notification = msg_fetch_notification,
+};
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index d9458ef7378a..99f3b0bfb956 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -343,7 +343,7 @@ static void scmi_optee_clear_channel(struct scmi_chan_info *cinfo)
 	struct scmi_optee_channel *channel = cinfo->transport_info;
 
 	if (!channel->tee_shm)
-		shmem_clear_channel(channel->req.shmem);
+		scmi_shmem_ops.clear_channel(channel->req.shmem);
 }
 
 static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *channel)
@@ -368,7 +368,7 @@ static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *ch
 static int setup_static_shmem(struct device *dev, struct scmi_chan_info *cinfo,
 			      struct scmi_optee_channel *channel)
 {
-	channel->req.shmem = setup_shmem_iomap(cinfo, dev, true, NULL);
+	channel->req.shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, true, NULL);
 	if (IS_ERR(channel->req.shmem))
 		return PTR_ERR(channel->req.shmem);
 
@@ -472,10 +472,10 @@ static int scmi_optee_send_message(struct scmi_chan_info *cinfo,
 	mutex_lock(&channel->mu);
 
 	if (channel->tee_shm) {
-		msg_tx_prepare(channel->req.msg, xfer);
-		ret = invoke_process_msg_channel(channel, msg_command_size(xfer));
+		scmi_msg_ops.tx_prepare(channel->req.msg, xfer);
+		ret = invoke_process_msg_channel(channel, scmi_msg_ops.command_size(xfer));
 	} else {
-		shmem_tx_prepare(channel->req.shmem, xfer, cinfo);
+		scmi_shmem_ops.tx_prepare(channel->req.shmem, xfer, cinfo);
 		ret = invoke_process_smt_channel(channel);
 	}
 
@@ -491,9 +491,9 @@ static void scmi_optee_fetch_response(struct scmi_chan_info *cinfo,
 	struct scmi_optee_channel *channel = cinfo->transport_info;
 
 	if (channel->tee_shm)
-		msg_fetch_response(channel->req.msg, channel->rx_len, xfer);
+		scmi_msg_ops.fetch_response(channel->req.msg, channel->rx_len, xfer);
 	else
-		shmem_fetch_response(channel->req.shmem, xfer);
+		scmi_shmem_ops.fetch_response(channel->req.shmem, xfer);
 }
 
 static void scmi_optee_mark_txdone(struct scmi_chan_info *cinfo, int ret,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index 06f68ee0e9f8..208a289642c3 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -2,7 +2,7 @@
 /*
  * For transport using shared mem structure.
  *
- * Copyright (C) 2019 ARM Ltd.
+ * Copyright (C) 2019-2024 ARM Ltd.
  */
 
 #include <linux/ktime.h>
@@ -34,8 +34,9 @@ struct scmi_shared_mem {
 	u8 msg_payload[];
 };
 
-void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
-		      struct scmi_xfer *xfer, struct scmi_chan_info *cinfo)
+static void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
+			     struct scmi_xfer *xfer,
+			     struct scmi_chan_info *cinfo)
 {
 	ktime_t stop;
 
@@ -75,13 +76,13 @@ void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
 		memcpy_toio(shmem->msg_payload, xfer->tx.buf, xfer->tx.len);
 }
 
-u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
+static u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem)
 {
 	return ioread32(&shmem->msg_header);
 }
 
-void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
-			  struct scmi_xfer *xfer)
+static void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
+				 struct scmi_xfer *xfer)
 {
 	size_t len = ioread32(&shmem->length);
 
@@ -93,8 +94,8 @@ void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
 	memcpy_fromio(xfer->rx.buf, shmem->msg_payload + 4, xfer->rx.len);
 }
 
-void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
-			      size_t max_len, struct scmi_xfer *xfer)
+static void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
+				     size_t max_len, struct scmi_xfer *xfer)
 {
 	size_t len = ioread32(&shmem->length);
 
@@ -105,13 +106,13 @@ void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
 	memcpy_fromio(xfer->rx.buf, shmem->msg_payload, xfer->rx.len);
 }
 
-void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem)
+static void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem)
 {
 	iowrite32(SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE, &shmem->channel_status);
 }
 
-bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
-		     struct scmi_xfer *xfer)
+static bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
+			    struct scmi_xfer *xfer)
 {
 	u16 xfer_id;
 
@@ -125,20 +126,20 @@ bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
 		 SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
 }
 
-bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem)
+static bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem)
 {
 	return (ioread32(&shmem->channel_status) &
 			SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
 }
 
-bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
+static bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
 {
 	return ioread32(&shmem->flags) & SCMI_SHMEM_FLAG_INTR_ENABLED;
 }
 
-void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
-				struct device *dev, bool tx,
-				struct resource *res)
+static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
+				       struct device *dev, bool tx,
+				       struct resource *res)
 {
 	struct device_node *shmem __free(device_node);
 	const char *desc = tx ? "Tx" : "Rx";
@@ -174,3 +175,15 @@ void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
 
 	return addr;
 }
+
+const struct scmi_shared_mem_operations scmi_shmem_ops = {
+	.tx_prepare = shmem_tx_prepare,
+	.read_header = shmem_read_header,
+	.fetch_response = shmem_fetch_response,
+	.fetch_notification = shmem_fetch_notification,
+	.clear_channel = shmem_clear_channel,
+	.poll_done = shmem_poll_done,
+	.channel_free = shmem_channel_free,
+	.channel_intr_enabled = shmem_channel_intr_enabled,
+	.setup_iomap = shmem_setup_iomap,
+};
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index 59b6c04b52bc..4cb86386c490 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -74,7 +74,7 @@ static irqreturn_t smc_msg_done_isr(int irq, void *data)
 	struct scmi_smc *scmi_info = data;
 
 	scmi_rx_callback(scmi_info->cinfo,
-			 shmem_read_header(scmi_info->shmem), NULL);
+			 scmi_shmem_ops.read_header(scmi_info->shmem), NULL);
 
 	return IRQ_HANDLED;
 }
@@ -141,7 +141,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!scmi_info)
 		return -ENOMEM;
 
-	scmi_info->shmem = setup_shmem_iomap(cinfo, dev, tx, &res);
+	scmi_info->shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, tx, &res);
 	if (IS_ERR(scmi_info->shmem))
 		return PTR_ERR(scmi_info->shmem);
 
@@ -226,7 +226,7 @@ static int smc_send_message(struct scmi_chan_info *cinfo,
 	 */
 	smc_channel_lock_acquire(scmi_info, xfer);
 
-	shmem_tx_prepare(scmi_info->shmem, xfer, cinfo);
+	scmi_shmem_ops.tx_prepare(scmi_info->shmem, xfer, cinfo);
 
 	if (scmi_info->cap_id != ULONG_MAX)
 		arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->cap_id, 0,
@@ -250,7 +250,7 @@ static void smc_fetch_response(struct scmi_chan_info *cinfo,
 {
 	struct scmi_smc *scmi_info = cinfo->transport_info;
 
-	shmem_fetch_response(scmi_info->shmem, xfer);
+	scmi_shmem_ops.fetch_response(scmi_info->shmem, xfer);
 }
 
 static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret,
diff --git a/drivers/firmware/arm_scmi/virtio.c b/drivers/firmware/arm_scmi/virtio.c
index 4892058445ce..736a0d41a458 100644
--- a/drivers/firmware/arm_scmi/virtio.c
+++ b/drivers/firmware/arm_scmi/virtio.c
@@ -295,7 +295,7 @@ static void scmi_vio_complete_cb(struct virtqueue *vqueue)
 		if (msg) {
 			msg->rx_len = length;
 			scmi_rx_callback(vioch->cinfo,
-					 msg_read_header(msg->input), msg);
+					 scmi_msg_ops.read_header(msg->input), msg);
 
 			scmi_finalize_message(vioch, msg);
 		}
@@ -340,7 +340,7 @@ static void scmi_vio_deferred_tx_worker(struct work_struct *work)
 		 */
 		if (msg->poll_status == VIO_MSG_NOT_POLLED)
 			scmi_rx_callback(vioch->cinfo,
-					 msg_read_header(msg->input), msg);
+					 scmi_msg_ops.read_header(msg->input), msg);
 
 		/* Free the processed message once done */
 		scmi_vio_msg_release(vioch, msg);
@@ -512,10 +512,10 @@ static int virtio_send_message(struct scmi_chan_info *cinfo,
 		return -EBUSY;
 	}
 
-	msg_tx_prepare(msg->request, xfer);
+	scmi_msg_ops.tx_prepare(msg->request, xfer);
 
-	sg_init_one(&sg_out, msg->request, msg_command_size(xfer));
-	sg_init_one(&sg_in, msg->input, msg_response_size(xfer));
+	sg_init_one(&sg_out, msg->request, scmi_msg_ops.command_size(xfer));
+	sg_init_one(&sg_in, msg->input, scmi_msg_ops.response_size(xfer));
 
 	spin_lock_irqsave(&vioch->lock, flags);
 
@@ -562,7 +562,7 @@ static void virtio_fetch_response(struct scmi_chan_info *cinfo,
 	struct scmi_vio_msg *msg = xfer->priv;
 
 	if (msg)
-		msg_fetch_response(msg->input, msg->rx_len, xfer);
+		scmi_msg_ops.fetch_response(msg->input, msg->rx_len, xfer);
 }
 
 static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
@@ -571,7 +571,7 @@ static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
 	struct scmi_vio_msg *msg = xfer->priv;
 
 	if (msg)
-		msg_fetch_notification(msg->input, msg->rx_len, max_len, xfer);
+		scmi_msg_ops.fetch_notification(msg->input, msg->rx_len, max_len, xfer);
 }
 
 /**
-- 
2.45.2

[PATCH v2 3/8] firmware: arm_scmi: Add support for standalone transport drivers

[Cristian Marussi]

Extend the core SCMI stack with structures and methods to allow for
transports to be split out as standalone drivers, while still supporting
old style transports, defined as built into the SCMI core stack.

No functional change.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
NOTE: old style transport support will be removed later in this series.

v1 --> v2
- fixed comit message
---
 drivers/firmware/arm_scmi/common.h | 84 ++++++++++++++++++++++++++++++
 drivers/firmware/arm_scmi/driver.c | 44 +++++++++++++++-
 drivers/firmware/arm_scmi/msg.c    |  5 ++
 drivers/firmware/arm_scmi/shmem.c  |  5 ++
 4 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 8e5751aaa600..4af06810eb39 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -349,6 +349,8 @@ struct scmi_shared_mem_operations {
 				     bool tx, struct resource *res);
 };
 
+const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void);
+
 /* declarations for message passing transports */
 struct scmi_msg_payld;
 
@@ -376,6 +378,88 @@ struct scmi_message_operations {
 				   size_t max_len, struct scmi_xfer *xfer);
 };
 
+const struct scmi_message_operations *scmi_message_operations_get(void);
+
+/**
+ * struct scmi_transport_core_operations  - Transpoert core operations
+ *
+ * @bad_message_trace: An helper to report a malformed/unexpected message
+ * @rx_callback: Callback to report received messages
+ * @shmem: Datagram operations for shared memory based transports
+ * @msg: Datagram operations for message based transports
+ */
+struct scmi_transport_core_operations {
+	void (*bad_message_trace)(struct scmi_chan_info *cinfo,
+				  u32 msg_hdr, enum scmi_bad_msg err);
+	void (*rx_callback)(struct scmi_chan_info *cinfo, u32 msg_hdr,
+			    void *priv);
+	const struct scmi_shared_mem_operations *shmem;
+	const struct scmi_message_operations *msg;
+};
+
+/**
+ * struct scmi_transport  - A structure representing a configured transport
+ *
+ * @supplier: Device representimng the transport and acting as a supplier for
+ *	      the core SCMI stack
+ * @desc: Transport descriptor
+ * @core_ops: A pointer to a pointer used by the core SCMI stack to make the
+ *	      core transport operations accessible to the transports.
+ */
+struct scmi_transport {
+	struct device *supplier;
+	const struct scmi_desc *desc;
+	struct scmi_transport_core_operations **core_ops;
+};
+
+#define DEFINE_SCMI_TRANSPORT_DRIVER(__trans, __match_table, __core_ptr)\
+static int __trans##_probe(struct platform_device *pdev)		\
+{									\
+	struct scmi_transport *scmi_trans;				\
+	struct platform_device *scmi_pdev;				\
+	struct device *dev = &pdev->dev;				\
+									\
+	scmi_trans = devm_kzalloc(dev, sizeof(*scmi_trans), GFP_KERNEL);\
+	if (!scmi_trans)						\
+		return -ENOMEM;						\
+									\
+	scmi_pdev = devm_kzalloc(dev, sizeof(*scmi_pdev), GFP_KERNEL);	\
+	if (!scmi_pdev)							\
+		return -ENOMEM;						\
+									\
+	scmi_trans->supplier = dev;					\
+	scmi_trans->desc = &__trans##_desc;				\
+	scmi_trans->core_ops = __core_ptr;				\
+									\
+	scmi_pdev->name = "arm-scmi";					\
+	scmi_pdev->id = PLATFORM_DEVID_AUTO;				\
+	scmi_pdev->dev.platform_data = scmi_trans;			\
+									\
+	device_set_of_node_from_dev(&scmi_pdev->dev, dev);		\
+									\
+	dev_set_drvdata(dev, scmi_pdev);				\
+									\
+	return platform_device_register(scmi_pdev);			\
+}									\
+									\
+static void __trans##_remove(struct platform_device *pdev)		\
+{									\
+	struct platform_device *scmi_pdev;				\
+									\
+	scmi_pdev = dev_get_drvdata(&pdev->dev);			\
+									\
+	platform_device_unregister(scmi_pdev);				\
+}									\
+									\
+static struct platform_driver __trans##_driver = {			\
+	.driver = {							\
+		   .name = #__trans "_transport",			\
+		   .of_match_table = __match_table,			\
+		   },							\
+	.probe = __trans##_probe,					\
+	.remove_new = __trans##_remove,					\
+}
+
 extern const struct scmi_shared_mem_operations scmi_shmem_ops;
 extern const struct scmi_message_operations scmi_msg_ops;
 
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 6b6957f4743f..a1892d4d8c69 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -194,6 +194,11 @@ struct scmi_info {
 #define bus_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, bus_nb)
 #define req_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, dev_req_nb)
 
+static struct scmi_transport_core_operations scmi_trans_core_ops = {
+	.bad_message_trace = scmi_bad_message_trace,
+	.rx_callback = scmi_rx_callback,
+};
+
 static unsigned long
 scmi_vendor_protocol_signature(unsigned int protocol_id, char *vendor_id,
 			       char *sub_vendor_id, u32 impl_ver)
@@ -2950,6 +2955,28 @@ static int scmi_debugfs_raw_mode_setup(struct scmi_info *info)
 	return ret;
 }
 
+static const struct scmi_desc *scmi_transport_lookup(struct device *dev)
+{
+	struct scmi_transport *trans;
+
+	trans = dev_get_platdata(dev);
+	if (!trans || !trans->desc || !trans->supplier || !trans->core_ops)
+		return NULL;
+
+	if (!device_link_add(dev, trans->supplier, DL_FLAG_AUTOREMOVE_CONSUMER)) {
+		dev_err(dev,
+			"Adding link to supplier transport device failed\n");
+		return NULL;
+	}
+
+	/* Provide core transport ops */
+	*trans->core_ops = &scmi_trans_core_ops;
+
+	dev_info(dev, "Using %s\n", dev_driver_string(trans->supplier));
+
+	return trans->desc;
+}
+
 static int scmi_probe(struct platform_device *pdev)
 {
 	int ret;
@@ -2962,8 +2989,14 @@ static int scmi_probe(struct platform_device *pdev)
 	struct device_node *child, *np = dev->of_node;
 
 	desc = of_device_get_match_data(dev);
-	if (!desc)
-		return -EINVAL;
+	if (!desc) {
+		desc = scmi_transport_lookup(dev);
+		if (!desc) {
+			err_str = "transport invalid\n";
+			ret = -EINVAL;
+			goto out_err;
+		}
+	}
 
 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
 	if (!info)
@@ -3130,6 +3163,7 @@ static int scmi_probe(struct platform_device *pdev)
 clear_ida:
 	ida_free(&scmi_id, info->id);
 
+out_err:
 	return dev_err_probe(dev, ret, "%s", err_str);
 }
 
@@ -3321,6 +3355,12 @@ static int __init scmi_driver_init(void)
 	if (ret)
 		return ret;
 
+	if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_SHMEM))
+		scmi_trans_core_ops.shmem = scmi_shared_mem_operations_get();
+
+	if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_MSG))
+		scmi_trans_core_ops.msg = scmi_message_operations_get();
+
 	if (IS_ENABLED(CONFIG_ARM_SCMI_NEED_DEBUGFS))
 		scmi_top_dentry = scmi_debugfs_init();
 
diff --git a/drivers/firmware/arm_scmi/msg.c b/drivers/firmware/arm_scmi/msg.c
index f4ba38afe0bb..0bed1d2825af 100644
--- a/drivers/firmware/arm_scmi/msg.c
+++ b/drivers/firmware/arm_scmi/msg.c
@@ -118,3 +118,8 @@ const struct scmi_message_operations scmi_msg_ops = {
 	.fetch_response = msg_fetch_response,
 	.fetch_notification = msg_fetch_notification,
 };
+
+const struct scmi_message_operations *scmi_message_operations_get(void)
+{
+	return &scmi_msg_ops;
+}
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index 208a289642c3..b1fc0c31495b 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -187,3 +187,8 @@ const struct scmi_shared_mem_operations scmi_shmem_ops = {
 	.channel_intr_enabled = shmem_channel_intr_enabled,
 	.setup_iomap = shmem_setup_iomap,
 };
+
+const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void)
+{
+	return &scmi_shmem_ops;
+}
-- 
2.45.2

[PATCH v2 4/8] firmware: arm_scmi: Make MBOX transport a standalone driver

[Cristian Marussi]

Make SCMI mailbox transport a standalne driver that can be optionally
loaded as a module.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
 drivers/firmware/arm_scmi/Kconfig             |  4 +-
 drivers/firmware/arm_scmi/Makefile            |  3 +-
 drivers/firmware/arm_scmi/common.h            |  3 --
 drivers/firmware/arm_scmi/driver.c            |  3 --
 .../{mailbox.c => scmi_transport_mailbox.c}   | 44 +++++++++++++------
 5 files changed, 36 insertions(+), 21 deletions(-)
 rename drivers/firmware/arm_scmi/{mailbox.c => scmi_transport_mailbox.c} (88%)

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index aa5842be19b2..135e34aefd70 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -75,7 +75,7 @@ config ARM_SCMI_HAVE_MSG
 	  available.
 
 config ARM_SCMI_TRANSPORT_MAILBOX
-	bool "SCMI transport based on Mailbox"
+	tristate "SCMI transport based on Mailbox"
 	depends on MAILBOX
 	select ARM_SCMI_HAVE_TRANSPORT
 	select ARM_SCMI_HAVE_SHMEM
@@ -85,6 +85,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
 
 	  If you want the ARM SCMI PROTOCOL stack to include support for a
 	  transport based on mailboxes, answer Y.
+	  This driver can also be built as a module.  If so, the module
+	  will be called scmi_transport_mailbox.
 
 config ARM_SCMI_TRANSPORT_OPTEE
 	bool "SCMI transport based on OP-TEE service"
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index fd59f58ce8a2..121612d75f0b 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -5,7 +5,6 @@ scmi-core-objs := $(scmi-bus-y)
 scmi-driver-y = driver.o notify.o
 scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
-scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += mailbox.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
@@ -14,6 +13,8 @@ scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o vol
 scmi-protocols-y += pinctrl.o
 scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
 
+obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
+
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o
 
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 4af06810eb39..0f2256a61622 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -286,9 +286,6 @@ int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle,
 int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 					    struct scmi_xfer *xfer,
 					    unsigned int timeout_ms);
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX
-extern const struct scmi_desc scmi_mailbox_desc;
-#endif
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC
 extern const struct scmi_desc scmi_smc_desc;
 #endif
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index a1892d4d8c69..96cf8ab4421e 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
 
 /* Each compatible listed below must have descriptor associated with it */
 static const struct of_device_id scmi_of_match[] = {
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX
-	{ .compatible = "arm,scmi", .data = &scmi_mailbox_desc },
-#endif
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE
 	{ .compatible = "linaro,scmi-optee", .data = &scmi_optee_desc },
 #endif
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/scmi_transport_mailbox.c
similarity index 88%
rename from drivers/firmware/arm_scmi/mailbox.c
rename to drivers/firmware/arm_scmi/scmi_transport_mailbox.c
index 60698efe8442..c19513e6dbdf 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_mailbox.c
@@ -11,6 +11,7 @@
 #include <linux/mailbox_client.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 
 #include "common.h"
@@ -36,11 +37,13 @@ struct scmi_mailbox {
 
 #define client_to_scmi_mailbox(c) container_of(c, struct scmi_mailbox, cl)
 
+static struct scmi_transport_core_operations *core;
+
 static void tx_prepare(struct mbox_client *cl, void *m)
 {
 	struct scmi_mailbox *smbox = client_to_scmi_mailbox(cl);
 
-	scmi_shmem_ops.tx_prepare(smbox->shmem, m, smbox->cinfo);
+	core->shmem->tx_prepare(smbox->shmem, m, smbox->cinfo);
 }
 
 static void rx_callback(struct mbox_client *cl, void *m)
@@ -56,15 +59,17 @@ static void rx_callback(struct mbox_client *cl, void *m)
 	 * a previous timed-out reply which arrived late could be wrongly
 	 * associated with the next pending transaction.
 	 */
-	if (cl->knows_txdone && !scmi_shmem_ops.channel_free(smbox->shmem)) {
+	if (cl->knows_txdone &&
+	    !core->shmem->channel_free(smbox->shmem)) {
 		dev_warn(smbox->cinfo->dev, "Ignoring spurious A2P IRQ !\n");
-		scmi_bad_message_trace(smbox->cinfo,
-				       scmi_shmem_ops.read_header(smbox->shmem),
-				       MSG_MBOX_SPURIOUS);
+		core->bad_message_trace(smbox->cinfo,
+			     core->shmem->read_header(smbox->shmem),
+							     MSG_MBOX_SPURIOUS);
 		return;
 	}
 
-	scmi_rx_callback(smbox->cinfo, scmi_shmem_ops.read_header(smbox->shmem), NULL);
+	core->rx_callback(smbox->cinfo,
+		      core->shmem->read_header(smbox->shmem), NULL);
 }
 
 static bool mailbox_chan_available(struct device_node *of_node, int idx)
@@ -192,7 +197,7 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!smbox)
 		return -ENOMEM;
 
-	smbox->shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, tx, NULL);
+	smbox->shmem = core->shmem->setup_iomap(cinfo, dev, tx, NULL);
 	if (IS_ERR(smbox->shmem))
 		return PTR_ERR(smbox->shmem);
 
@@ -293,7 +298,7 @@ static void mailbox_fetch_response(struct scmi_chan_info *cinfo,
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	scmi_shmem_ops.fetch_response(smbox->shmem, xfer);
+	core->shmem->fetch_response(smbox->shmem, xfer);
 }
 
 static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
@@ -301,7 +306,7 @@ static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	scmi_shmem_ops.fetch_notification(smbox->shmem, max_len, xfer);
+	core->shmem->fetch_notification(smbox->shmem, max_len, xfer);
 }
 
 static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
@@ -310,9 +315,9 @@ static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
 	struct mbox_chan *intr_chan;
 	int ret;
 
-	scmi_shmem_ops.clear_channel(smbox->shmem);
+	core->shmem->clear_channel(smbox->shmem);
 
-	if (!scmi_shmem_ops.channel_intr_enabled(smbox->shmem))
+	if (!core->shmem->channel_intr_enabled(smbox->shmem))
 		return;
 
 	if (smbox->chan_platform_receiver)
@@ -335,7 +340,7 @@ mailbox_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
 {
 	struct scmi_mailbox *smbox = cinfo->transport_info;
 
-	return scmi_shmem_ops.poll_done(smbox->shmem, xfer);
+	return core->shmem->poll_done(smbox->shmem, xfer);
 }
 
 static const struct scmi_transport_ops scmi_mailbox_ops = {
@@ -350,9 +355,22 @@ static const struct scmi_transport_ops scmi_mailbox_ops = {
 	.poll_done = mailbox_poll_done,
 };
 
-const struct scmi_desc scmi_mailbox_desc = {
+static const struct scmi_desc scmi_mailbox_desc = {
 	.ops = &scmi_mailbox_ops,
 	.max_rx_timeout_ms = 30, /* We may increase this if required */
 	.max_msg = 20, /* Limited by MBOX_TX_QUEUE_LEN */
 	.max_msg_size = 128,
 };
+
+static const struct of_device_id scmi_of_match[] = {
+	{ .compatible = "arm,scmi" },
+	{ /* Sentinel */ },
+};
+
+DEFINE_SCMI_TRANSPORT_DRIVER(scmi_mailbox, scmi_of_match, &core);
+module_platform_driver(scmi_mailbox_driver);
+
+MODULE_ALIAS("scmi-transport-mailbox");
+MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
+MODULE_DESCRIPTION("SCMI Mailbox Transport driver");
+MODULE_LICENSE("GPL");
-- 
2.45.2

[PATCH v2 5/8] firmware: arm_scmi: Make SMC transport a standalone driver

[Cristian Marussi]

Make SCMI SMC transport a standalone driver that can be optionally
loaded as a module.

CC: Peng Fan <peng.fan@nxp.com>
CC: Nikunj Kela <quic_nkela@quicinc.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
- make scmi_smc_desc static
---
 drivers/firmware/arm_scmi/Kconfig             |  4 ++-
 drivers/firmware/arm_scmi/Makefile            |  2 +-
 drivers/firmware/arm_scmi/common.h            |  3 --
 drivers/firmware/arm_scmi/driver.c            |  5 ---
 .../arm_scmi/{smc.c => scmi_transport_smc.c}  | 33 +++++++++++++++----
 5 files changed, 30 insertions(+), 17 deletions(-)
 rename drivers/firmware/arm_scmi/{smc.c => scmi_transport_smc.c} (89%)

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index 135e34aefd70..a4d44ef8bf45 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -102,7 +102,7 @@ config ARM_SCMI_TRANSPORT_OPTEE
 	  transport based on OP-TEE SCMI service, answer Y.
 
 config ARM_SCMI_TRANSPORT_SMC
-	bool "SCMI transport based on SMC"
+	tristate "SCMI transport based on SMC"
 	depends on HAVE_ARM_SMCCC_DISCOVERY
 	select ARM_SCMI_HAVE_TRANSPORT
 	select ARM_SCMI_HAVE_SHMEM
@@ -112,6 +112,8 @@ config ARM_SCMI_TRANSPORT_SMC
 
 	  If you want the ARM SCMI PROTOCOL stack to include support for a
 	  transport based on SMC, answer Y.
+	  This driver can also be built as a module.  If so, the module
+	  will be called scmi_transport_smc.
 
 config ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE
 	bool "Enable atomic mode support for SCMI SMC transport"
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index 121612d75f0b..6868a47fa4ab 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -5,7 +5,6 @@ scmi-core-objs := $(scmi-bus-y)
 scmi-driver-y = driver.o notify.o
 scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
-scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
@@ -13,6 +12,7 @@ scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o vol
 scmi-protocols-y += pinctrl.o
 scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
 
+obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
 
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 0f2256a61622..edb786cde25c 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -286,9 +286,6 @@ int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle,
 int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 					    struct scmi_xfer *xfer,
 					    unsigned int timeout_ms);
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC
-extern const struct scmi_desc scmi_smc_desc;
-#endif
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
 extern const struct scmi_desc scmi_virtio_desc;
 #endif
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 96cf8ab4421e..b14c5326930a 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -3254,11 +3254,6 @@ static const struct of_device_id scmi_of_match[] = {
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE
 	{ .compatible = "linaro,scmi-optee", .data = &scmi_optee_desc },
 #endif
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC
-	{ .compatible = "arm,scmi-smc", .data = &scmi_smc_desc},
-	{ .compatible = "arm,scmi-smc-param", .data = &scmi_smc_desc},
-	{ .compatible = "qcom,scmi-smc", .data = &scmi_smc_desc},
-#endif
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
 	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
 #endif
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/scmi_transport_smc.c
similarity index 89%
rename from drivers/firmware/arm_scmi/smc.c
rename to drivers/firmware/arm_scmi/scmi_transport_smc.c
index 4cb86386c490..291e33207536 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_smc.c
@@ -3,7 +3,7 @@
  * System Control and Management Interface (SCMI) Message SMC/HVC
  * Transport driver
  *
- * Copyright 2020 NXP
+ * Copyright 2020-2024 NXP
  */
 
 #include <linux/arm-smccc.h>
@@ -16,6 +16,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/limits.h>
+#include <linux/platform_device.h>
 #include <linux/processor.h>
 #include <linux/slab.h>
 
@@ -69,12 +70,14 @@ struct scmi_smc {
 	unsigned long cap_id;
 };
 
+static struct scmi_transport_core_operations *core;
+
 static irqreturn_t smc_msg_done_isr(int irq, void *data)
 {
 	struct scmi_smc *scmi_info = data;
 
-	scmi_rx_callback(scmi_info->cinfo,
-			 scmi_shmem_ops.read_header(scmi_info->shmem), NULL);
+	core->rx_callback(scmi_info->cinfo,
+			  core->shmem->read_header(scmi_info->shmem), NULL);
 
 	return IRQ_HANDLED;
 }
@@ -141,7 +144,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
 	if (!scmi_info)
 		return -ENOMEM;
 
-	scmi_info->shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, tx, &res);
+	scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res);
 	if (IS_ERR(scmi_info->shmem))
 		return PTR_ERR(scmi_info->shmem);
 
@@ -226,7 +229,7 @@ static int smc_send_message(struct scmi_chan_info *cinfo,
 	 */
 	smc_channel_lock_acquire(scmi_info, xfer);
 
-	scmi_shmem_ops.tx_prepare(scmi_info->shmem, xfer, cinfo);
+	core->shmem->tx_prepare(scmi_info->shmem, xfer, cinfo);
 
 	if (scmi_info->cap_id != ULONG_MAX)
 		arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->cap_id, 0,
@@ -250,7 +253,7 @@ static void smc_fetch_response(struct scmi_chan_info *cinfo,
 {
 	struct scmi_smc *scmi_info = cinfo->transport_info;
 
-	scmi_shmem_ops.fetch_response(scmi_info->shmem, xfer);
+	core->shmem->fetch_response(scmi_info->shmem, xfer);
 }
 
 static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret,
@@ -270,7 +273,7 @@ static const struct scmi_transport_ops scmi_smc_ops = {
 	.fetch_response = smc_fetch_response,
 };
 
-const struct scmi_desc scmi_smc_desc = {
+static const struct scmi_desc scmi_smc_desc = {
 	.ops = &scmi_smc_ops,
 	.max_rx_timeout_ms = 30,
 	.max_msg = 20,
@@ -286,3 +289,19 @@ const struct scmi_desc scmi_smc_desc = {
 	.sync_cmds_completed_on_ret = true,
 	.atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE),
 };
+
+static const struct of_device_id scmi_of_match[] = {
+	{ .compatible = "arm,scmi-smc" },
+	{ .compatible = "arm,scmi-smc-param" },
+	{ .compatible = "qcom,scmi-smc" },
+	{ /* Sentinel */ },
+};
+
+DEFINE_SCMI_TRANSPORT_DRIVER(scmi_smc, scmi_of_match, &core);
+module_platform_driver(scmi_smc_driver);
+
+MODULE_ALIAS("scmi-transport-smc");
+MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
+MODULE_AUTHOR("Nikunj Kela <quic_nkela@quicinc.com>");
+MODULE_DESCRIPTION("SCMI SMC Transport driver");
+MODULE_LICENSE("GPL");
-- 
2.45.2

[PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a standalone driver

[Cristian Marussi]

Make SCMI OPTEE transport a standalone driver that can be optionally
loaded as a module.

CC: Etienne Carriere <etienne.carriere@foss.st.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
- handle platform_driver_register() failures
---
 drivers/firmware/arm_scmi/Kconfig             |  6 +-
 drivers/firmware/arm_scmi/Makefile            |  2 +-
 drivers/firmware/arm_scmi/common.h            |  3 -
 drivers/firmware/arm_scmi/driver.c            |  3 -
 .../{optee.c => scmi_transport_optee.c}       | 91 ++++++++++---------
 5 files changed, 52 insertions(+), 53 deletions(-)
 rename drivers/firmware/arm_scmi/{optee.c => scmi_transport_optee.c} (90%)

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index a4d44ef8bf45..def7e3f09356 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -89,8 +89,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
 	  will be called scmi_transport_mailbox.
 
 config ARM_SCMI_TRANSPORT_OPTEE
-	bool "SCMI transport based on OP-TEE service"
-	depends on OPTEE=y || OPTEE=ARM_SCMI_PROTOCOL
+	tristate "SCMI transport based on OP-TEE service"
+	depends on OPTEE
 	select ARM_SCMI_HAVE_TRANSPORT
 	select ARM_SCMI_HAVE_SHMEM
 	select ARM_SCMI_HAVE_MSG
@@ -100,6 +100,8 @@ config ARM_SCMI_TRANSPORT_OPTEE
 
 	  If you want the ARM SCMI PROTOCOL stack to include support for a
 	  transport based on OP-TEE SCMI service, answer Y.
+	  This driver can also be built as a module.  If so, the module
+	  will be called scmi_transport_optee.
 
 config ARM_SCMI_TRANSPORT_SMC
 	tristate "SCMI transport based on SMC"
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index 6868a47fa4ab..b04119ce972f 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -7,13 +7,13 @@ scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
-scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
 scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
 scmi-protocols-y += pinctrl.o
 scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
 
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
+obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += scmi_transport_optee.o
 
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
 obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index edb786cde25c..0ce1d804b3fc 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -289,9 +289,6 @@ int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
 extern const struct scmi_desc scmi_virtio_desc;
 #endif
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE
-extern const struct scmi_desc scmi_optee_desc;
-#endif
 
 void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv);
 
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index b14c5326930a..67b416c7f2f5 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
 
 /* Each compatible listed below must have descriptor associated with it */
 static const struct of_device_id scmi_of_match[] = {
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE
-	{ .compatible = "linaro,scmi-optee", .data = &scmi_optee_desc },
-#endif
 #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
 	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
 #endif
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/scmi_transport_optee.c
similarity index 90%
rename from drivers/firmware/arm_scmi/optee.c
rename to drivers/firmware/arm_scmi/scmi_transport_optee.c
index 99f3b0bfb956..7a16c8d3e213 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_optee.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (C) 2019-2021 Linaro Ltd.
+ * Copyright (C) 2019-2024 Linaro Ltd.
  */
 
 #include <linux/io.h>
@@ -9,6 +9,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/tee_drv.h>
 #include <linux/uuid.h>
@@ -148,12 +149,11 @@ struct scmi_optee_agent {
 	struct list_head channel_list;
 };
 
+static struct scmi_transport_core_operations *core;
+
 /* There can be only 1 SCMI service in OP-TEE we connect to */
 static struct scmi_optee_agent *scmi_optee_private;
 
-/* Forward reference to scmi_optee transport initialization */
-static int scmi_optee_init(void);
-
 /* Open a session toward SCMI OP-TEE service with REE_KERNEL identity */
 static int open_session(struct scmi_optee_agent *agent, u32 *tee_session)
 {
@@ -312,24 +312,6 @@ static int invoke_process_msg_channel(struct scmi_optee_channel *channel, size_t
 	return 0;
 }
 
-static int scmi_optee_link_supplier(struct device *dev)
-{
-	if (!scmi_optee_private) {
-		if (scmi_optee_init())
-			dev_dbg(dev, "Optee bus not yet ready\n");
-
-		/* Wait for optee bus */
-		return -EPROBE_DEFER;
-	}
-
-	if (!device_link_add(dev, scmi_optee_private->dev, DL_FLAG_AUTOREMOVE_CONSUMER)) {
-		dev_err(dev, "Adding link to supplier optee device failed\n");
-		return -ECANCELED;
-	}
-
-	return 0;
-}
-
 static bool scmi_optee_chan_available(struct device_node *of_node, int idx)
 {
 	u32 channel_id;
@@ -343,7 +325,7 @@ static void scmi_optee_clear_channel(struct scmi_chan_info *cinfo)
 	struct scmi_optee_channel *channel = cinfo->transport_info;
 
 	if (!channel->tee_shm)
-		scmi_shmem_ops.clear_channel(channel->req.shmem);
+		core->shmem->clear_channel(channel->req.shmem);
 }
 
 static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *channel)
@@ -368,7 +350,7 @@ static int setup_dynamic_shmem(struct device *dev, struct scmi_optee_channel *ch
 static int setup_static_shmem(struct device *dev, struct scmi_chan_info *cinfo,
 			      struct scmi_optee_channel *channel)
 {
-	channel->req.shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, true, NULL);
+	channel->req.shmem = core->shmem->setup_iomap(cinfo, dev, true, NULL);
 	if (IS_ERR(channel->req.shmem))
 		return PTR_ERR(channel->req.shmem);
 
@@ -472,10 +454,11 @@ static int scmi_optee_send_message(struct scmi_chan_info *cinfo,
 	mutex_lock(&channel->mu);
 
 	if (channel->tee_shm) {
-		scmi_msg_ops.tx_prepare(channel->req.msg, xfer);
-		ret = invoke_process_msg_channel(channel, scmi_msg_ops.command_size(xfer));
+		core->msg->tx_prepare(channel->req.msg, xfer);
+		ret = invoke_process_msg_channel(channel,
+						 core->msg->command_size(xfer));
 	} else {
-		scmi_shmem_ops.tx_prepare(channel->req.shmem, xfer, cinfo);
+		core->shmem->tx_prepare(channel->req.shmem, xfer, cinfo);
 		ret = invoke_process_smt_channel(channel);
 	}
 
@@ -491,9 +474,10 @@ static void scmi_optee_fetch_response(struct scmi_chan_info *cinfo,
 	struct scmi_optee_channel *channel = cinfo->transport_info;
 
 	if (channel->tee_shm)
-		scmi_msg_ops.fetch_response(channel->req.msg, channel->rx_len, xfer);
+		core->msg->fetch_response(channel->req.msg,
+					  channel->rx_len, xfer);
 	else
-		scmi_shmem_ops.fetch_response(channel->req.shmem, xfer);
+		core->shmem->fetch_response(channel->req.shmem, xfer);
 }
 
 static void scmi_optee_mark_txdone(struct scmi_chan_info *cinfo, int ret,
@@ -505,7 +489,6 @@ static void scmi_optee_mark_txdone(struct scmi_chan_info *cinfo, int ret,
 }
 
 static struct scmi_transport_ops scmi_optee_ops = {
-	.link_supplier = scmi_optee_link_supplier,
 	.chan_available = scmi_optee_chan_available,
 	.chan_setup = scmi_optee_chan_setup,
 	.chan_free = scmi_optee_chan_free,
@@ -520,6 +503,21 @@ static int scmi_optee_ctx_match(struct tee_ioctl_version_data *ver, const void *
 	return ver->impl_id == TEE_IMPL_ID_OPTEE;
 }
 
+static const struct scmi_desc scmi_optee_desc = {
+	.ops = &scmi_optee_ops,
+	.max_rx_timeout_ms = 30,
+	.max_msg = 20,
+	.max_msg_size = SCMI_OPTEE_MAX_MSG_SIZE,
+	.sync_cmds_completed_on_ret = true,
+};
+
+static const struct of_device_id scmi_of_match[] = {
+	{ .compatible = "linaro,scmi-optee" },
+	{ /* Sentinel */ },
+};
+
+DEFINE_SCMI_TRANSPORT_DRIVER(scmi_optee, scmi_of_match, &core);
+
 static int scmi_optee_service_probe(struct device *dev)
 {
 	struct scmi_optee_agent *agent;
@@ -555,6 +553,12 @@ static int scmi_optee_service_probe(struct device *dev)
 	smp_mb();
 	scmi_optee_private = agent;
 
+	ret = platform_driver_register(&scmi_optee_driver);
+	if (ret) {
+		scmi_optee_private = NULL;
+		goto err;
+	}
+
 	return 0;
 
 err:
@@ -573,6 +577,8 @@ static int scmi_optee_service_remove(struct device *dev)
 	if (!list_empty(&scmi_optee_private->channel_list))
 		return -EBUSY;
 
+	platform_driver_unregister(&scmi_optee_driver);
+
 	/* Ensure cleared reference is visible before resources are released */
 	smp_store_mb(scmi_optee_private, NULL);
 
@@ -591,7 +597,7 @@ static const struct tee_client_device_id scmi_optee_service_id[] = {
 
 MODULE_DEVICE_TABLE(tee, scmi_optee_service_id);
 
-static struct tee_client_driver scmi_optee_driver = {
+static struct tee_client_driver scmi_optee_service_driver = {
 	.id_table	= scmi_optee_service_id,
 	.driver		= {
 		.name = "scmi-optee",
@@ -601,22 +607,19 @@ static struct tee_client_driver scmi_optee_driver = {
 	},
 };
 
-static int scmi_optee_init(void)
+static int __init scmi_transport_optee_init(void)
 {
-	return driver_register(&scmi_optee_driver.driver);
+	return driver_register(&scmi_optee_service_driver.driver);
 }
+module_init(scmi_transport_optee_init);
 
-static void scmi_optee_exit(void)
+static void __exit scmi_transport_optee_exit(void)
 {
-	if (scmi_optee_private)
-		driver_unregister(&scmi_optee_driver.driver);
+	driver_unregister(&scmi_optee_service_driver.driver);
 }
+module_exit(scmi_transport_optee_exit);
 
-const struct scmi_desc scmi_optee_desc = {
-	.transport_exit = scmi_optee_exit,
-	.ops = &scmi_optee_ops,
-	.max_rx_timeout_ms = 30,
-	.max_msg = 20,
-	.max_msg_size = SCMI_OPTEE_MAX_MSG_SIZE,
-	.sync_cmds_completed_on_ret = true,
-};
+MODULE_ALIAS("scmi-transport-optee");
+MODULE_AUTHOR("Etienne Carriere <etienne.carriere@foss.st.com>");
+MODULE_DESCRIPTION("SCMI OPTEE Transport driver");
+MODULE_LICENSE("GPL");
-- 
2.45.2

[PATCH v2 7/8] firmware: arm_scmi: Make VirtIO transport a standalone driver

[Cristian Marussi]

Make SCMI VirtIO transport a standalone driver that can be optionally
loaded as a module.

CC: Michael S. Tsirkin <mst@redhat.com>
CC: Igor Skalkin <igor.skalkin@opensynergy.com>
CC: Peter Hilber <peter.hilber@opensynergy.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
- handle platform_driver_register() failures
- make scmi_virtio_desc static
  | Reported-by: kernel test robot <lkp@intel.com>
  | Closes:
  https://lore.kernel.org/oe-kbuild-all/202407081344.9OceqFie-lkp@intel.com/
---
 drivers/firmware/arm_scmi/Kconfig             |   6 +-
 drivers/firmware/arm_scmi/Makefile            |   2 +-
 drivers/firmware/arm_scmi/common.h            |   3 -
 drivers/firmware/arm_scmi/driver.c            |   3 -
 .../{virtio.c => scmi_transport_virtio.c}     | 103 +++++++++---------
 5 files changed, 59 insertions(+), 58 deletions(-)
 rename drivers/firmware/arm_scmi/{virtio.c => scmi_transport_virtio.c} (94%)

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index def7e3f09356..c18d86e9d8d7 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -132,8 +132,8 @@ config ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE
 	  primitives all over instead. If unsure say N.
 
 config ARM_SCMI_TRANSPORT_VIRTIO
-	bool "SCMI transport based on VirtIO"
-	depends on VIRTIO=y || VIRTIO=ARM_SCMI_PROTOCOL
+	tristate "SCMI transport based on VirtIO"
+	depends on VIRTIO
 	select ARM_SCMI_HAVE_TRANSPORT
 	select ARM_SCMI_HAVE_MSG
 	help
@@ -141,6 +141,8 @@ config ARM_SCMI_TRANSPORT_VIRTIO
 
 	  If you want the ARM SCMI PROTOCOL stack to include support for a
 	  transport based on VirtIO, answer Y.
+	  This driver can also be built as a module.  If so, the module
+	  will be called scmi_transport_virtio.
 
 config ARM_SCMI_TRANSPORT_VIRTIO_VERSION1_COMPLIANCE
 	bool "SCMI VirtIO transport Version 1 compliance"
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index b04119ce972f..846b4939258d 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -6,12 +6,12 @@ scmi-driver-y = driver.o notify.o
 scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
 scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
-scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
 scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
 scmi-protocols-y += pinctrl.o
 scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
 
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o
+obj-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += scmi_transport_virtio.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
 obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += scmi_transport_optee.o
 
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 0ce1d804b3fc..28d52b9102c3 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -286,9 +286,6 @@ int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle,
 int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 					    struct scmi_xfer *xfer,
 					    unsigned int timeout_ms);
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
-extern const struct scmi_desc scmi_virtio_desc;
-#endif
 
 void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv);
 
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 67b416c7f2f5..2a1f87c97abe 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
 
 /* Each compatible listed below must have descriptor associated with it */
 static const struct of_device_id scmi_of_match[] = {
-#ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
-	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
-#endif
 	{ /* Sentinel */ },
 };
 
diff --git a/drivers/firmware/arm_scmi/virtio.c b/drivers/firmware/arm_scmi/scmi_transport_virtio.c
similarity index 94%
rename from drivers/firmware/arm_scmi/virtio.c
rename to drivers/firmware/arm_scmi/scmi_transport_virtio.c
index 736a0d41a458..cc6a77ce5a9d 100644
--- a/drivers/firmware/arm_scmi/virtio.c
+++ b/drivers/firmware/arm_scmi/scmi_transport_virtio.c
@@ -3,8 +3,8 @@
  * Virtio Transport driver for Arm System Control and Management Interface
  * (SCMI).
  *
- * Copyright (C) 2020-2022 OpenSynergy.
- * Copyright (C) 2021-2022 ARM Ltd.
+ * Copyright (C) 2020-2024 OpenSynergy.
+ * Copyright (C) 2021-2024 ARM Ltd.
  */
 
 /**
@@ -19,6 +19,7 @@
 
 #include <linux/completion.h>
 #include <linux/errno.h>
+#include <linux/platform_device.h>
 #include <linux/refcount.h>
 #include <linux/slab.h>
 #include <linux/virtio.h>
@@ -108,6 +109,8 @@ struct scmi_vio_msg {
 	refcount_t users;
 };
 
+static struct scmi_transport_core_operations *core;
+
 /* Only one SCMI VirtIO device can possibly exist */
 static struct virtio_device *scmi_vdev;
 
@@ -294,8 +297,9 @@ static void scmi_vio_complete_cb(struct virtqueue *vqueue)
 
 		if (msg) {
 			msg->rx_len = length;
-			scmi_rx_callback(vioch->cinfo,
-					 scmi_msg_ops.read_header(msg->input), msg);
+			core->rx_callback(vioch->cinfo,
+					  core->msg->read_header(msg->input),
+					  msg);
 
 			scmi_finalize_message(vioch, msg);
 		}
@@ -339,8 +343,9 @@ static void scmi_vio_deferred_tx_worker(struct work_struct *work)
 		 * is no more processed elsewhere so no poll_lock needed.
 		 */
 		if (msg->poll_status == VIO_MSG_NOT_POLLED)
-			scmi_rx_callback(vioch->cinfo,
-					 scmi_msg_ops.read_header(msg->input), msg);
+			core->rx_callback(vioch->cinfo,
+					  core->msg->read_header(msg->input),
+					  msg);
 
 		/* Free the processed message once done */
 		scmi_vio_msg_release(vioch, msg);
@@ -368,23 +373,6 @@ static unsigned int virtio_get_max_msg(struct scmi_chan_info *base_cinfo)
 	return vioch->max_msg;
 }
 
-static int virtio_link_supplier(struct device *dev)
-{
-	if (!scmi_vdev) {
-		dev_notice(dev,
-			   "Deferring probe after not finding a bound scmi-virtio device\n");
-		return -EPROBE_DEFER;
-	}
-
-	if (!device_link_add(dev, &scmi_vdev->dev,
-			     DL_FLAG_AUTOREMOVE_CONSUMER)) {
-		dev_err(dev, "Adding link to supplier virtio device failed\n");
-		return -ECANCELED;
-	}
-
-	return 0;
-}
-
 static bool virtio_chan_available(struct device_node *of_node, int idx)
 {
 	struct scmi_vio_channel *channels, *vioch = NULL;
@@ -512,10 +500,10 @@ static int virtio_send_message(struct scmi_chan_info *cinfo,
 		return -EBUSY;
 	}
 
-	scmi_msg_ops.tx_prepare(msg->request, xfer);
+	core->msg->tx_prepare(msg->request, xfer);
 
-	sg_init_one(&sg_out, msg->request, scmi_msg_ops.command_size(xfer));
-	sg_init_one(&sg_in, msg->input, scmi_msg_ops.response_size(xfer));
+	sg_init_one(&sg_out, msg->request, core->msg->command_size(xfer));
+	sg_init_one(&sg_in, msg->input, core->msg->response_size(xfer));
 
 	spin_lock_irqsave(&vioch->lock, flags);
 
@@ -562,7 +550,7 @@ static void virtio_fetch_response(struct scmi_chan_info *cinfo,
 	struct scmi_vio_msg *msg = xfer->priv;
 
 	if (msg)
-		scmi_msg_ops.fetch_response(msg->input, msg->rx_len, xfer);
+		core->msg->fetch_response(msg->input, msg->rx_len, xfer);
 }
 
 static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
@@ -571,7 +559,8 @@ static void virtio_fetch_notification(struct scmi_chan_info *cinfo,
 	struct scmi_vio_msg *msg = xfer->priv;
 
 	if (msg)
-		scmi_msg_ops.fetch_notification(msg->input, msg->rx_len, max_len, xfer);
+		core->msg->fetch_notification(msg->input, msg->rx_len,
+					      max_len, xfer);
 }
 
 /**
@@ -671,7 +660,7 @@ static void virtio_mark_txdone(struct scmi_chan_info *cinfo, int ret,
  * the message we are polling for could be alternatively delivered via usual
  * IRQs callbacks on another core which happened to have IRQs enabled while we
  * are actively polling for it here: in such a case it will be handled as such
- * by scmi_rx_callback() and the polling loop in the SCMI Core TX path will be
+ * by rx_callback() and the polling loop in the SCMI Core TX path will be
  * transparently terminated anyway.
  *
  * Return: True once polling has successfully completed.
@@ -792,7 +781,6 @@ static bool virtio_poll_done(struct scmi_chan_info *cinfo,
 }
 
 static const struct scmi_transport_ops scmi_virtio_ops = {
-	.link_supplier = virtio_link_supplier,
 	.chan_available = virtio_chan_available,
 	.chan_setup = virtio_chan_setup,
 	.chan_free = virtio_chan_free,
@@ -804,6 +792,22 @@ static const struct scmi_transport_ops scmi_virtio_ops = {
 	.poll_done = virtio_poll_done,
 };
 
+static const struct scmi_desc scmi_virtio_desc = {
+	.ops = &scmi_virtio_ops,
+	/* for non-realtime virtio devices */
+	.max_rx_timeout_ms = VIRTIO_MAX_RX_TIMEOUT_MS,
+	.max_msg = 0, /* overridden by virtio_get_max_msg() */
+	.max_msg_size = VIRTIO_SCMI_MAX_MSG_SIZE,
+	.atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE),
+};
+
+static const struct of_device_id scmi_of_match[] = {
+	{ .compatible = "arm,scmi-virtio" },
+	{ /* Sentinel */ },
+};
+
+DEFINE_SCMI_TRANSPORT_DRIVER(scmi_virtio, scmi_of_match, &core);
+
 static int scmi_vio_probe(struct virtio_device *vdev)
 {
 	struct device *dev = &vdev->dev;
@@ -864,14 +868,27 @@ static int scmi_vio_probe(struct virtio_device *vdev)
 	}
 
 	vdev->priv = channels;
+
 	/* Ensure initialized scmi_vdev is visible */
 	smp_store_mb(scmi_vdev, vdev);
 
+	ret = platform_driver_register(&scmi_virtio_driver);
+	if (ret) {
+		vdev->priv = NULL;
+		vdev->config->del_vqs(vdev);
+		/* Ensure NULLified scmi_vdev is visible */
+		smp_store_mb(scmi_vdev, NULL);
+
+		return ret;
+	}
+
 	return 0;
 }
 
 static void scmi_vio_remove(struct virtio_device *vdev)
 {
+	platform_driver_unregister(&scmi_virtio_driver);
+
 	/*
 	 * Once we get here, virtio_chan_free() will have already been called by
 	 * the SCMI core for any existing channel and, as a consequence, all the
@@ -916,23 +933,11 @@ static struct virtio_driver virtio_scmi_driver = {
 	.validate = scmi_vio_validate,
 };
 
-static int __init virtio_scmi_init(void)
-{
-	return register_virtio_driver(&virtio_scmi_driver);
-}
-
-static void virtio_scmi_exit(void)
-{
-	unregister_virtio_driver(&virtio_scmi_driver);
-}
+module_virtio_driver(virtio_scmi_driver);
 
-const struct scmi_desc scmi_virtio_desc = {
-	.transport_init = virtio_scmi_init,
-	.transport_exit = virtio_scmi_exit,
-	.ops = &scmi_virtio_ops,
-	/* for non-realtime virtio devices */
-	.max_rx_timeout_ms = VIRTIO_MAX_RX_TIMEOUT_MS,
-	.max_msg = 0, /* overridden by virtio_get_max_msg() */
-	.max_msg_size = VIRTIO_SCMI_MAX_MSG_SIZE,
-	.atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO_ATOMIC_ENABLE),
-};
+MODULE_ALIAS("scmi-transport-virtio");
+MODULE_AUTHOR("Igor Skalkin <igor.skalkin@opensynergy.com>");
+MODULE_AUTHOR("Peter Hilber <peter.hilber@opensynergy.com>");
+MODULE_AUTHOR("Cristian Marussi <cristian.marussi@arm.com>");
+MODULE_DESCRIPTION("SCMI VirtIO Transport driver");
+MODULE_LICENSE("GPL");
-- 
2.45.2

[PATCH v2 8/8] firmware: arm_scmi: Remove legacy transport-layer code

[Cristian Marussi]

Since all SCMI transports have been made standalone drivers, remove all the
core SCMI stack legacy support that was needed to run transports as built
into the stack.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
 drivers/firmware/arm_scmi/common.h | 18 ------
 drivers/firmware/arm_scmi/driver.c | 96 ++++--------------------------
 drivers/firmware/arm_scmi/msg.c    |  2 +-
 drivers/firmware/arm_scmi/shmem.c  |  2 +-
 4 files changed, 15 insertions(+), 103 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 28d52b9102c3..0a31d3b2f2c2 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -183,7 +183,6 @@ struct scmi_chan_info {
 /**
  * struct scmi_transport_ops - Structure representing a SCMI transport ops
  *
- * @link_supplier: Optional callback to add link to a supplier device
  * @chan_available: Callback to check if channel is available or not
  * @chan_setup: Callback to allocate and setup a channel
  * @chan_free: Callback to free a channel
@@ -198,7 +197,6 @@ struct scmi_chan_info {
  * @poll_done: Callback to poll transfer status
  */
 struct scmi_transport_ops {
-	int (*link_supplier)(struct device *dev);
 	bool (*chan_available)(struct device_node *of_node, int idx);
 	int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev,
 			  bool tx);
@@ -219,12 +217,6 @@ struct scmi_transport_ops {
 /**
  * struct scmi_desc - Description of SoC integration
  *
- * @transport_init: An optional function that a transport can provide to
- *		    initialize some transport-specific setup during SCMI core
- *		    initialization, so ahead of SCMI core probing.
- * @transport_exit: An optional function that a transport can provide to
- *		    de-initialize some transport-specific setup during SCMI core
- *		    de-initialization, so after SCMI core removal.
  * @ops: Pointer to the transport specific ops structure
  * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds)
  * @max_msg: Maximum number of messages for a channel type (tx or rx) that can
@@ -245,8 +237,6 @@ struct scmi_transport_ops {
  *		    when requested.
  */
 struct scmi_desc {
-	int (*transport_init)(void);
-	void (*transport_exit)(void);
 	const struct scmi_transport_ops *ops;
 	int max_rx_timeout_ms;
 	int max_msg;
@@ -287,8 +277,6 @@ int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 					    struct scmi_xfer *xfer,
 					    unsigned int timeout_ms);
 
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv);
-
 enum scmi_bad_msg {
 	MSG_UNEXPECTED = -1,
 	MSG_INVALID = -2,
@@ -297,9 +285,6 @@ enum scmi_bad_msg {
 	MSG_MBOX_SPURIOUS = -5,
 };
 
-void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
-			    enum scmi_bad_msg err);
-
 /* shmem related declarations */
 struct scmi_shared_mem;
 
@@ -448,9 +433,6 @@ static struct platform_driver __trans##_driver = {			\
 	.remove_new = __trans##_remove,					\
 }
 
-extern const struct scmi_shared_mem_operations scmi_shmem_ops;
-extern const struct scmi_message_operations scmi_msg_ops;
-
 void scmi_notification_instance_data_set(const struct scmi_handle *handle,
 					 void *priv);
 void *scmi_notification_instance_data_get(const struct scmi_handle *handle);
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 2a1f87c97abe..ea0595193dec 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -194,6 +194,11 @@ struct scmi_info {
 #define bus_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, bus_nb)
 #define req_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, dev_req_nb)
 
+static void scmi_rx_callback(struct scmi_chan_info *cinfo,
+			     u32 msg_hdr, void *priv);
+static void scmi_bad_message_trace(struct scmi_chan_info *cinfo,
+				   u32 msg_hdr, enum scmi_bad_msg err);
+
 static struct scmi_transport_core_operations scmi_trans_core_ops = {
 	.bad_message_trace = scmi_bad_message_trace,
 	.rx_callback = scmi_rx_callback,
@@ -838,8 +843,8 @@ scmi_xfer_lookup_unlocked(struct scmi_xfers_info *minfo, u16 xfer_id)
  * timed-out message that arrives and as such, can be traced only referring to
  * the header content, since the payload is missing/unreliable.
  */
-void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
-			    enum scmi_bad_msg err)
+static void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
+				   enum scmi_bad_msg err)
 {
 	char *tag;
 	struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
@@ -1165,7 +1170,8 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo,
  * NOTE: This function will be invoked in IRQ context, hence should be
  * as optimal as possible.
  */
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv)
+static void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr,
+			     void *priv)
 {
 	u8 msg_type = MSG_XTRACT_TYPE(msg_hdr);
 
@@ -2988,14 +2994,11 @@ static int scmi_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *child, *np = dev->of_node;
 
-	desc = of_device_get_match_data(dev);
+	desc = scmi_transport_lookup(dev);
 	if (!desc) {
-		desc = scmi_transport_lookup(dev);
-		if (!desc) {
-			err_str = "transport invalid\n";
-			ret = -EINVAL;
-			goto out_err;
-		}
+		err_str = "transport invalid\n";
+		ret = -EINVAL;
+		goto out_err;
 	}
 
 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
@@ -3035,14 +3038,6 @@ static int scmi_probe(struct platform_device *pdev)
 			 info->atomic_threshold);
 	handle->is_transport_atomic = scmi_is_transport_atomic;
 
-	if (desc->ops->link_supplier) {
-		ret = desc->ops->link_supplier(dev);
-		if (ret) {
-			err_str = "transport not ready\n";
-			goto clear_ida;
-		}
-	}
-
 	/* Setup all channels described in the DT at first */
 	ret = scmi_channels_setup(info);
 	if (ret) {
@@ -3249,72 +3244,16 @@ static struct attribute *versions_attrs[] = {
 };
 ATTRIBUTE_GROUPS(versions);
 
-/* Each compatible listed below must have descriptor associated with it */
-static const struct of_device_id scmi_of_match[] = {
-	{ /* Sentinel */ },
-};
-
-MODULE_DEVICE_TABLE(of, scmi_of_match);
-
 static struct platform_driver scmi_driver = {
 	.driver = {
 		   .name = "arm-scmi",
 		   .suppress_bind_attrs = true,
-		   .of_match_table = scmi_of_match,
 		   .dev_groups = versions_groups,
 		   },
 	.probe = scmi_probe,
 	.remove_new = scmi_remove,
 };
 
-/**
- * __scmi_transports_setup  - Common helper to call transport-specific
- * .init/.exit code if provided.
- *
- * @init: A flag to distinguish between init and exit.
- *
- * Note that, if provided, we invoke .init/.exit functions for all the
- * transports currently compiled in.
- *
- * Return: 0 on Success.
- */
-static inline int __scmi_transports_setup(bool init)
-{
-	int ret = 0;
-	const struct of_device_id *trans;
-
-	for (trans = scmi_of_match; trans->data; trans++) {
-		const struct scmi_desc *tdesc = trans->data;
-
-		if ((init && !tdesc->transport_init) ||
-		    (!init && !tdesc->transport_exit))
-			continue;
-
-		if (init)
-			ret = tdesc->transport_init();
-		else
-			tdesc->transport_exit();
-
-		if (ret) {
-			pr_err("SCMI transport %s FAILED initialization!\n",
-			       trans->compatible);
-			break;
-		}
-	}
-
-	return ret;
-}
-
-static int __init scmi_transports_init(void)
-{
-	return __scmi_transports_setup(true);
-}
-
-static void __exit scmi_transports_exit(void)
-{
-	__scmi_transports_setup(false);
-}
-
 static struct dentry *scmi_debugfs_init(void)
 {
 	struct dentry *d;
@@ -3330,17 +3269,10 @@ static struct dentry *scmi_debugfs_init(void)
 
 static int __init scmi_driver_init(void)
 {
-	int ret;
-
 	/* Bail out if no SCMI transport was configured */
 	if (WARN_ON(!IS_ENABLED(CONFIG_ARM_SCMI_HAVE_TRANSPORT)))
 		return -EINVAL;
 
-	/* Initialize any compiled-in transport which provided an init/exit */
-	ret = scmi_transports_init();
-	if (ret)
-		return ret;
-
 	if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_SHMEM))
 		scmi_trans_core_ops.shmem = scmi_shared_mem_operations_get();
 
@@ -3380,8 +3312,6 @@ static void __exit scmi_driver_exit(void)
 	scmi_powercap_unregister();
 	scmi_pinctrl_unregister();
 
-	scmi_transports_exit();
-
 	platform_driver_unregister(&scmi_driver);
 
 	debugfs_remove_recursive(scmi_top_dentry);
diff --git a/drivers/firmware/arm_scmi/msg.c b/drivers/firmware/arm_scmi/msg.c
index 0bed1d2825af..ca916817878d 100644
--- a/drivers/firmware/arm_scmi/msg.c
+++ b/drivers/firmware/arm_scmi/msg.c
@@ -110,7 +110,7 @@ static void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
 	memcpy(xfer->rx.buf, msg->msg_payload, xfer->rx.len);
 }
 
-const struct scmi_message_operations scmi_msg_ops = {
+static const struct scmi_message_operations scmi_msg_ops = {
 	.tx_prepare = msg_tx_prepare,
 	.command_size = msg_command_size,
 	.response_size = msg_response_size,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index b1fc0c31495b..e17eb603d871 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -176,7 +176,7 @@ static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
 	return addr;
 }
 
-const struct scmi_shared_mem_operations scmi_shmem_ops = {
+static const struct scmi_shared_mem_operations scmi_shmem_ops = {
 	.tx_prepare = shmem_tx_prepare,
 	.read_header = shmem_read_header,
 	.fetch_response = shmem_fetch_response,
-- 
2.45.2

Re: [PATCH v2 5/8] firmware: arm_scmi: Make SMC transport a standalone driver

[Nikunj Kela]

On 7/10/2024 10:31 AM, Cristian Marussi wrote:
> Make SCMI SMC transport a standalone driver that can be optionally
> loaded as a module.
>
> CC: Peng Fan <peng.fan@nxp.com>
> CC: Nikunj Kela <quic_nkela@quicinc.com>
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---

Tested-by: Nikunj Kela <quic_nkela@quicinc.com>

Tested this series on SA8775p Qualcomm platform that uses Qualcomm SMC
transport.

> v1 --> v2
> - make scmi_smc_desc static
> ---
>  drivers/firmware/arm_scmi/Kconfig             |  4 ++-
>  drivers/firmware/arm_scmi/Makefile            |  2 +-
>  drivers/firmware/arm_scmi/common.h            |  3 --
>  drivers/firmware/arm_scmi/driver.c            |  5 ---
>  .../arm_scmi/{smc.c => scmi_transport_smc.c}  | 33 +++++++++++++++----
>  5 files changed, 30 insertions(+), 17 deletions(-)
>  rename drivers/firmware/arm_scmi/{smc.c => scmi_transport_smc.c} (89%)
>
> diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
> index 135e34aefd70..a4d44ef8bf45 100644
> --- a/drivers/firmware/arm_scmi/Kconfig
> +++ b/drivers/firmware/arm_scmi/Kconfig
> @@ -102,7 +102,7 @@ config ARM_SCMI_TRANSPORT_OPTEE
>  	  transport based on OP-TEE SCMI service, answer Y.
>  
>  config ARM_SCMI_TRANSPORT_SMC
> -	bool "SCMI transport based on SMC"
> +	tristate "SCMI transport based on SMC"
>  	depends on HAVE_ARM_SMCCC_DISCOVERY
>  	select ARM_SCMI_HAVE_TRANSPORT
>  	select ARM_SCMI_HAVE_SHMEM
> @@ -112,6 +112,8 @@ config ARM_SCMI_TRANSPORT_SMC
>  
>  	  If you want the ARM SCMI PROTOCOL stack to include support for a
>  	  transport based on SMC, answer Y.
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called scmi_transport_smc.
>  
>  config ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE
>  	bool "Enable atomic mode support for SCMI SMC transport"
> diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
> index 121612d75f0b..6868a47fa4ab 100644
> --- a/drivers/firmware/arm_scmi/Makefile
> +++ b/drivers/firmware/arm_scmi/Makefile
> @@ -5,7 +5,6 @@ scmi-core-objs := $(scmi-bus-y)
>  scmi-driver-y = driver.o notify.o
>  scmi-driver-$(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
>  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
> -scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
>  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
>  scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
>  scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
> @@ -13,6 +12,7 @@ scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o system.o vol
>  scmi-protocols-y += pinctrl.o
>  scmi-module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
>  
> +obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += scmi_transport_smc.o
>  obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += scmi_transport_mailbox.o
>  
>  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
> diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
> index 0f2256a61622..edb786cde25c 100644
> --- a/drivers/firmware/arm_scmi/common.h
> +++ b/drivers/firmware/arm_scmi/common.h
> @@ -286,9 +286,6 @@ int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle,
>  int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
>  					    struct scmi_xfer *xfer,
>  					    unsigned int timeout_ms);
> -#ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC
> -extern const struct scmi_desc scmi_smc_desc;
> -#endif
>  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
>  extern const struct scmi_desc scmi_virtio_desc;
>  #endif
> diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
> index 96cf8ab4421e..b14c5326930a 100644
> --- a/drivers/firmware/arm_scmi/driver.c
> +++ b/drivers/firmware/arm_scmi/driver.c
> @@ -3254,11 +3254,6 @@ static const struct of_device_id scmi_of_match[] = {
>  #ifdef CONFIG_ARM_SCMI_TRANSPORT_OPTEE
>  	{ .compatible = "linaro,scmi-optee", .data = &scmi_optee_desc },
>  #endif
> -#ifdef CONFIG_ARM_SCMI_TRANSPORT_SMC
> -	{ .compatible = "arm,scmi-smc", .data = &scmi_smc_desc},
> -	{ .compatible = "arm,scmi-smc-param", .data = &scmi_smc_desc},
> -	{ .compatible = "qcom,scmi-smc", .data = &scmi_smc_desc},
> -#endif
>  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
>  	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
>  #endif
> diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/scmi_transport_smc.c
> similarity index 89%
> rename from drivers/firmware/arm_scmi/smc.c
> rename to drivers/firmware/arm_scmi/scmi_transport_smc.c
> index 4cb86386c490..291e33207536 100644
> --- a/drivers/firmware/arm_scmi/smc.c
> +++ b/drivers/firmware/arm_scmi/scmi_transport_smc.c
> @@ -3,7 +3,7 @@
>   * System Control and Management Interface (SCMI) Message SMC/HVC
>   * Transport driver
>   *
> - * Copyright 2020 NXP
> + * Copyright 2020-2024 NXP
>   */
>  
>  #include <linux/arm-smccc.h>
> @@ -16,6 +16,7 @@
>  #include <linux/of_address.h>
>  #include <linux/of_irq.h>
>  #include <linux/limits.h>
> +#include <linux/platform_device.h>
>  #include <linux/processor.h>
>  #include <linux/slab.h>
>  
> @@ -69,12 +70,14 @@ struct scmi_smc {
>  	unsigned long cap_id;
>  };
>  
> +static struct scmi_transport_core_operations *core;
> +
>  static irqreturn_t smc_msg_done_isr(int irq, void *data)
>  {
>  	struct scmi_smc *scmi_info = data;
>  
> -	scmi_rx_callback(scmi_info->cinfo,
> -			 scmi_shmem_ops.read_header(scmi_info->shmem), NULL);
> +	core->rx_callback(scmi_info->cinfo,
> +			  core->shmem->read_header(scmi_info->shmem), NULL);
>  
>  	return IRQ_HANDLED;
>  }
> @@ -141,7 +144,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
>  	if (!scmi_info)
>  		return -ENOMEM;
>  
> -	scmi_info->shmem = scmi_shmem_ops.setup_iomap(cinfo, dev, tx, &res);
> +	scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res);
>  	if (IS_ERR(scmi_info->shmem))
>  		return PTR_ERR(scmi_info->shmem);
>  
> @@ -226,7 +229,7 @@ static int smc_send_message(struct scmi_chan_info *cinfo,
>  	 */
>  	smc_channel_lock_acquire(scmi_info, xfer);
>  
> -	scmi_shmem_ops.tx_prepare(scmi_info->shmem, xfer, cinfo);
> +	core->shmem->tx_prepare(scmi_info->shmem, xfer, cinfo);
>  
>  	if (scmi_info->cap_id != ULONG_MAX)
>  		arm_smccc_1_1_invoke(scmi_info->func_id, scmi_info->cap_id, 0,
> @@ -250,7 +253,7 @@ static void smc_fetch_response(struct scmi_chan_info *cinfo,
>  {
>  	struct scmi_smc *scmi_info = cinfo->transport_info;
>  
> -	scmi_shmem_ops.fetch_response(scmi_info->shmem, xfer);
> +	core->shmem->fetch_response(scmi_info->shmem, xfer);
>  }
>  
>  static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret,
> @@ -270,7 +273,7 @@ static const struct scmi_transport_ops scmi_smc_ops = {
>  	.fetch_response = smc_fetch_response,
>  };
>  
> -const struct scmi_desc scmi_smc_desc = {
> +static const struct scmi_desc scmi_smc_desc = {
>  	.ops = &scmi_smc_ops,
>  	.max_rx_timeout_ms = 30,
>  	.max_msg = 20,
> @@ -286,3 +289,19 @@ const struct scmi_desc scmi_smc_desc = {
>  	.sync_cmds_completed_on_ret = true,
>  	.atomic_enabled = IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE),
>  };
> +
> +static const struct of_device_id scmi_of_match[] = {
> +	{ .compatible = "arm,scmi-smc" },
> +	{ .compatible = "arm,scmi-smc-param" },
> +	{ .compatible = "qcom,scmi-smc" },
> +	{ /* Sentinel */ },
> +};
> +
> +DEFINE_SCMI_TRANSPORT_DRIVER(scmi_smc, scmi_of_match, &core);
> +module_platform_driver(scmi_smc_driver);
> +
> +MODULE_ALIAS("scmi-transport-smc");
> +MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
> +MODULE_AUTHOR("Nikunj Kela <quic_nkela@quicinc.com>");
> +MODULE_DESCRIPTION("SCMI SMC Transport driver");
> +MODULE_LICENSE("GPL");

Re: [PATCH v2 5/8] firmware: arm_scmi: Make SMC transport a standalone driver

[Cristian Marussi]

On Wed, Jul 10, 2024 at 02:04:16PM -0700, Nikunj Kela wrote:
> 
> On 7/10/2024 10:31 AM, Cristian Marussi wrote:
> > Make SCMI SMC transport a standalone driver that can be optionally
> > loaded as a module.
> >
> > CC: Peng Fan <peng.fan@nxp.com>
> > CC: Nikunj Kela <quic_nkela@quicinc.com>
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> 
> Tested-by: Nikunj Kela <quic_nkela@quicinc.com>
> 
> Tested this series on SA8775p Qualcomm platform that uses Qualcomm SMC
> transport.
> 

Thanks Nikunj !
Cristian

RE: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet handling helpers

[Peng Fan]

> Subject: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet
> handling helpers
> 
> Introduce a pair of structures initialized to contain all the existing
> packet handling helpers, both for transports based on shared memory
> and messages.
> 
> No functional change.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
> v1 --> v2
> - fixed commit message
> ---
......

> d33a704e5814..f4ba38afe0bb 100644
> --- a/drivers/firmware/arm_scmi/msg.c
> +++ b/drivers/firmware/arm_scmi/msg.c
> @@ -4,8 +4,8 @@
>   *
>   * Derived from shm.c.
>   *
> - * Copyright (C) 2019-2021 ARM Ltd.
> - * Copyright (C) 2020-2021 OpenSynergy GmbH
> + * Copyright (C) 2019-2024 ARM Ltd.
> + * Copyright (C) 2020-2024 OpenSynergy GmbH

Nitpick: OpenSynergy year should be kept unchanged?

Otherwise looks good:
Reviewed-by: Peng Fan <peng.fan@nxp.com>

RE: [PATCH v2 3/8] firmware: arm_scmi: Add support for standalone transport drivers

[Peng Fan]

> Subject: [PATCH v2 3/8] firmware: arm_scmi: Add support for
> standalone transport drivers
> 
> Extend the core SCMI stack with structures and methods to allow for
> transports to be split out as standalone drivers, while still supporting
> old style transports, defined as built into the SCMI core stack.
> 
> No functional change.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
> NOTE: old style transport support will be removed later in this series.
> 
> v1 --> v2
> - fixed comit message
> ---
>  drivers/firmware/arm_scmi/common.h | 84
> ++++++++++++++++++++++++++++++
> drivers/firmware/arm_scmi/driver.c | 44 +++++++++++++++-
>  drivers/firmware/arm_scmi/msg.c    |  5 ++
>  drivers/firmware/arm_scmi/shmem.c  |  5 ++
>  4 files changed, 136 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/arm_scmi/common.h
> b/drivers/firmware/arm_scmi/common.h
> index 8e5751aaa600..4af06810eb39 100644
> --- a/drivers/firmware/arm_scmi/common.h
> +++ b/drivers/firmware/arm_scmi/common.h
> @@ -349,6 +349,8 @@ struct scmi_shared_mem_operations {
>  				     bool tx, struct resource *res);  };
> 
> +const struct scmi_shared_mem_operations
> +*scmi_shared_mem_operations_get(void);
> +
>  /* declarations for message passing transports */  struct
> scmi_msg_payld;
> 
> @@ -376,6 +378,88 @@ struct scmi_message_operations {
>  				   size_t max_len, struct scmi_xfer
> *xfer);  };
> 
> +const struct scmi_message_operations
> +*scmi_message_operations_get(void);
> +
> +/**
> + * struct scmi_transport_core_operations  - Transpoert core
> operations
> + *
> + * @bad_message_trace: An helper to report a
> malformed/unexpected
> +message
> + * @rx_callback: Callback to report received messages
> + * @shmem: Datagram operations for shared memory based
> transports
> + * @msg: Datagram operations for message based transports  */
> struct
> +scmi_transport_core_operations {
> +	void (*bad_message_trace)(struct scmi_chan_info *cinfo,
> +				  u32 msg_hdr, enum scmi_bad_msg
> err);
> +	void (*rx_callback)(struct scmi_chan_info *cinfo, u32 msg_hdr,
> +			    void *priv);
> +	const struct scmi_shared_mem_operations *shmem;
> +	const struct scmi_message_operations *msg; };
> +
> +/**
> + * struct scmi_transport  - A structure representing a configured
> +transport
> + *
> + * @supplier: Device representimng the transport and acting as a
> supplier for
> + *	      the core SCMI stack
> + * @desc: Transport descriptor
> + * @core_ops: A pointer to a pointer used by the core SCMI stack to
> make the
> + *	      core transport operations accessible to the transports.
> + */
> +struct scmi_transport {
> +	struct device *supplier;
> +	const struct scmi_desc *desc;
> +	struct scmi_transport_core_operations **core_ops; };
> +
> +#define DEFINE_SCMI_TRANSPORT_DRIVER(__trans, __match_table,
> __core_ptr)\
> +static int __trans##_probe(struct platform_device *pdev)		\
> +{
> 	\
> +	struct scmi_transport *scmi_trans;
> 	\
> +	struct platform_device *scmi_pdev;
> 	\
> +	struct device *dev = &pdev->dev;				\
> +
> 	\
> +	scmi_trans = devm_kzalloc(dev, sizeof(*scmi_trans),
> GFP_KERNEL);\
> +	if (!scmi_trans)						\
> +		return -ENOMEM;
> 		\
> +
> 	\
> +	scmi_pdev = devm_kzalloc(dev, sizeof(*scmi_pdev),
> GFP_KERNEL);	\
> +	if (!scmi_pdev)
> 	\
> +		return -ENOMEM;
> 		\
> +
> 	\
> +	scmi_trans->supplier = dev;
> 	\
> +	scmi_trans->desc = &__trans##_desc;
> 	\
> +	scmi_trans->core_ops = __core_ptr;
> 	\
> +
> 	\
> +	scmi_pdev->name = "arm-scmi";
> 	\
> +	scmi_pdev->id = PLATFORM_DEVID_AUTO;
> 		\
> +	scmi_pdev->dev.platform_data = scmi_trans;
> 	\
> +
> 	\
> +	device_set_of_node_from_dev(&scmi_pdev->dev, dev);
> 	\
> +
> 	\
> +	dev_set_drvdata(dev, scmi_pdev);
> 	\
> +
> 	\
> +	return platform_device_register(scmi_pdev);
> 	\
> +}
> 	\
> +
> 	\
> +static void __trans##_remove(struct platform_device *pdev)
> 	\
> +{
> 	\
> +	struct platform_device *scmi_pdev;
> 	\
> +
> 	\
> +	scmi_pdev = dev_get_drvdata(&pdev->dev);
> 	\
> +
> 	\
> +	platform_device_unregister(scmi_pdev);
> 	\
> +}
> 	\
> +
> 	\
> +static struct platform_driver __trans##_driver = {			\
> +	.driver = {
> 	\
> +		   .name = #__trans "_transport",			\
> +		   .of_match_table = __match_table,
> 	\
> +		   },
> 	\
> +	.probe = __trans##_probe,
> 	\
> +	.remove_new = __trans##_remove,
> 		\
> +}
> +
>  extern const struct scmi_shared_mem_operations scmi_shmem_ops;
> extern const struct scmi_message_operations scmi_msg_ops;
> 
> diff --git a/drivers/firmware/arm_scmi/driver.c
> b/drivers/firmware/arm_scmi/driver.c
> index 6b6957f4743f..a1892d4d8c69 100644
> --- a/drivers/firmware/arm_scmi/driver.c
> +++ b/drivers/firmware/arm_scmi/driver.c
> @@ -194,6 +194,11 @@ struct scmi_info {
>  #define bus_nb_to_scmi_info(nb)	container_of(nb, struct
> scmi_info, bus_nb)
>  #define req_nb_to_scmi_info(nb)	container_of(nb, struct
> scmi_info, dev_req_nb)
> 
> +static struct scmi_transport_core_operations scmi_trans_core_ops = {
> +	.bad_message_trace = scmi_bad_message_trace,
> +	.rx_callback = scmi_rx_callback,
> +};
> +
>  static unsigned long
>  scmi_vendor_protocol_signature(unsigned int protocol_id, char
> *vendor_id,
>  			       char *sub_vendor_id, u32 impl_ver) @@
> -2950,6 +2955,28 @@ static int scmi_debugfs_raw_mode_setup(struct
> scmi_info *info)
>  	return ret;
>  }
> 
> +static const struct scmi_desc *scmi_transport_lookup(struct device
> +*dev) {
> +	struct scmi_transport *trans;
> +
> +	trans = dev_get_platdata(dev);
> +	if (!trans || !trans->desc || !trans->supplier || !trans-
> >core_ops)
> +		return NULL;
> +
> +	if (!device_link_add(dev, trans->supplier,
> DL_FLAG_AUTOREMOVE_CONSUMER)) {

Just wonder why this is needed?

> +		dev_err(dev,
> +			"Adding link to supplier transport device
> failed\n");
> +		return NULL;
> +	}
> +
> +	/* Provide core transport ops */
> +	*trans->core_ops = &scmi_trans_core_ops;
> +
> +	dev_info(dev, "Using %s\n", dev_driver_string(trans->supplier));
> +
> +	return trans->desc;
> +}
> +
>  static int scmi_probe(struct platform_device *pdev)  {
>  	int ret;
> @@ -2962,8 +2989,14 @@ static int scmi_probe(struct
> platform_device *pdev)
>  	struct device_node *child, *np = dev->of_node;
> 
>  	desc = of_device_get_match_data(dev);
> -	if (!desc)
> -		return -EINVAL;
> +	if (!desc) {
> +		desc = scmi_transport_lookup(dev);

from the code, It is not actually a lookup operation.
How about scmi_transport_setup?

Regards,
Peng.

RE: [PATCH v2 4/8] firmware: arm_scmi: Make MBOX transport a standalone driver

[Peng Fan]

> Subject: [PATCH v2 4/8] firmware: arm_scmi: Make MBOX transport a
> standalone driver
> 
> Make SCMI mailbox transport a standalne driver that can be optionally
> loaded as a module.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>

Reviewed-by: Peng Fan <peng.fan@nxp.com>

RE: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a standalone driver

[Peng Fan]

> Subject: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a
> standalone driver
> 
> Make SCMI OPTEE transport a standalone driver that can be optionally
> loaded as a module.
> 
> CC: Etienne Carriere <etienne.carriere@foss.st.com>
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
> v1 --> v2
> - handle platform_driver_register() failures
> ---
>  drivers/firmware/arm_scmi/Kconfig             |  6 +-
>  drivers/firmware/arm_scmi/Makefile            |  2 +-
>  drivers/firmware/arm_scmi/common.h            |  3 -
>  drivers/firmware/arm_scmi/driver.c            |  3 -
>  .../{optee.c => scmi_transport_optee.c}       | 91 ++++++++++---------
>  5 files changed, 52 insertions(+), 53 deletions(-)  rename
> drivers/firmware/arm_scmi/{optee.c => scmi_transport_optee.c} (90%)
> 
> diff --git a/drivers/firmware/arm_scmi/Kconfig
> b/drivers/firmware/arm_scmi/Kconfig
> index a4d44ef8bf45..def7e3f09356 100644
> --- a/drivers/firmware/arm_scmi/Kconfig
> +++ b/drivers/firmware/arm_scmi/Kconfig
> @@ -89,8 +89,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
>  	  will be called scmi_transport_mailbox.
> 
>  config ARM_SCMI_TRANSPORT_OPTEE
> -	bool "SCMI transport based on OP-TEE service"
> -	depends on OPTEE=y || OPTEE=ARM_SCMI_PROTOCOL
> +	tristate "SCMI transport based on OP-TEE service"
> +	depends on OPTEE
>  	select ARM_SCMI_HAVE_TRANSPORT
>  	select ARM_SCMI_HAVE_SHMEM
>  	select ARM_SCMI_HAVE_MSG
> @@ -100,6 +100,8 @@ config ARM_SCMI_TRANSPORT_OPTEE
> 
>  	  If you want the ARM SCMI PROTOCOL stack to include
> support for a
>  	  transport based on OP-TEE SCMI service, answer Y.
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called scmi_transport_optee.
> 
>  config ARM_SCMI_TRANSPORT_SMC
>  	tristate "SCMI transport based on SMC"
> diff --git a/drivers/firmware/arm_scmi/Makefile
> b/drivers/firmware/arm_scmi/Makefile
> index 6868a47fa4ab..b04119ce972f 100644
> --- a/drivers/firmware/arm_scmi/Makefile
> +++ b/drivers/firmware/arm_scmi/Makefile
> @@ -7,13 +7,13 @@ scmi-driver-
> $(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
>  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
>  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
>  scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
> -scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
> scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o
> system.o voltage.o powercap.o  scmi-protocols-y += pinctrl.o  scmi-
> module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
> 
>  obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) +=
> scmi_transport_smc.o
>  obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) +=
> scmi_transport_mailbox.o
> +obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) +=
> scmi_transport_optee.o
> 
>  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
>  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o diff --git
> a/drivers/firmware/arm_scmi/common.h
> b/drivers/firmware/arm_scmi/common.h
> index edb786cde25c..0ce1d804b3fc 100644
> --- a/drivers/firmware/arm_scmi/common.h
> +++ b/drivers/firmware/arm_scmi/common.h
> @@ -289,9 +289,6 @@ int
> scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info
> *cinfo,  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO  extern const
> struct scmi_desc scmi_virtio_desc;  #endif -#ifdef
> CONFIG_ARM_SCMI_TRANSPORT_OPTEE -extern const struct
> scmi_desc scmi_optee_desc; -#endif
> 
>  void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr,
> void *priv);
> 
> diff --git a/drivers/firmware/arm_scmi/driver.c
> b/drivers/firmware/arm_scmi/driver.c
> index b14c5326930a..67b416c7f2f5 100644
> --- a/drivers/firmware/arm_scmi/driver.c
> +++ b/drivers/firmware/arm_scmi/driver.c
> @@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
> 
>  /* Each compatible listed below must have descriptor associated with
> it */  static const struct of_device_id scmi_of_match[] = { -#ifdef
> CONFIG_ARM_SCMI_TRANSPORT_OPTEE
> -	{ .compatible = "linaro,scmi-optee", .data =
> &scmi_optee_desc },
> -#endif
>  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
>  	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
> #endif diff --git a/drivers/firmware/arm_scmi/optee.c
> b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> similarity index 90%
> rename from drivers/firmware/arm_scmi/optee.c rename to
> drivers/firmware/arm_scmi/scmi_transport_optee.c
> index 99f3b0bfb956..7a16c8d3e213 100644
> --- a/drivers/firmware/arm_scmi/optee.c
> +++ b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> @@ -1,6 +1,6 @@
>  // SPDX-License-Identifier: GPL-2.0
>  /*
> - * Copyright (C) 2019-2021 Linaro Ltd.
> + * Copyright (C) 2019-2024 Linaro Ltd.

This should be kept unchanged?

Regards,
Peng.

RE: [PATCH 0/8] Make SCMI transport as standalone drivers

[Peng Fan]

> Subject: [PATCH 0/8] Make SCMI transport as standalone drivers

You may need use V2 here :)
> 
> Hi all,
> 
> Till now the SCMI transport layer was being built embedded into in the
> core SCMI stack.
> 
> Some of these transports, despite being currently part of the main
> SCMI module, are indeed also registered with different subsystems like
> optee or virtio, and actively probed also by those: this led to a few
> awkward and convoluted tricks to properly handle such interactions at
> boot time in the SCMI stack.
> 
> Moreover some partner expressed the desire to be able to fully
> modularize the transports components.
> 
> This series aim to make all such transports as standalone drivers that
> can be optionally loaded as modules.
> 
> In order to do this, at first some new mechanism is introduced to
> support this new capability while maintaining, in parallel, the old
> legacy embedded transports; then each transport, one by one, is
> transitioned to be a standalone driver and finally the old legacy
> support for embedded transport is removed.
> 
> Patch [1/8] is a mostly unrelated (but much needed) clean-up from
> Peng, which I included in this series to avoid conflicts at merge.
> 
> Patch [2/8] simply collects the existing datagram manipulation helpers
> in a pair of function pointers structures, in preparation for later reworks.
> 
> Patch [3/8] adds the bulk of the new logic to the core SCMI stack and
> then each existing transport is transitioned to be a standalone driver in
> patches 4,5,6,7 while shuffling around the compatibles. (no DT change
> is needed of curse for backward compatibility) While doing this I kept
> the module authorship in line with the main
> author(S) as spitted out by git-blame.
> 
> Finally patch [8/8] removes all the legacy dead code from the core
> SCMI stack.
> 
> No new symbol EXPORT has been added.
> 
> The new transport drivers have been tested, as built-in and LKM, as
> follows:
> 
> - mailbox on JUNO
> - virtio on emulation
> - optee on QEMU/optee using Linaro setup
> 
> Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> testing commands, replies, delayed responses and notification.
> 
> Multiple virtual SCMI instances support has been tested too.
> 
> SMC has NOT been tested/exercised at run-time, only compile-tested.
> (due to lack of hardware)
> 
> Note that in this new setup, all the probe deferral and retries between
> the SCMI core stack and the transports has been removed, since no
> more needed.
> 
> Moreover the new drivers have been tested also with a fully
> modularized SCMI stack, i.e.:
> 
>   scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor
> modules ]
> 
> ToBeDone:
>  - completely remove any dependency at build time at the Kconfig level
> between
>    the SCMI core and the transport drivers: so that the transports will be
>    dependent only on the related subsystems (optee/virtio/mailbox/smc)
>    (easy to be done but maybe it is not worth...)
>  - integrate per-platform transport configuration capabilities
>    (max_rx_timeout_ms & friends..)
> 
> Based on sudeep/for-next/scmi/updates.
> 
> Any feedback, and especially testing (:D) is welcome.
> 

For the v2 patchset:
Tested-by: Peng Fan <peng.fan@nxp.com>  #i.MX95-19x19-EVK

Regards,
Peng.

> Thanks,
> Cristian
> 
> ---
> v1 --> v2
> - fixed setup_shmem_iomap to address also SMC needs (QC/nikunj)
>   (silencing also warnings by kernel test robot <lkp@intel.com>)
> - using __free OF cleanup.h magic in setup_shmme_iomap
> - properly handle platform_driver_register() failures (Dan)
> - fixed a few commit message style
> - added a few missing static in scmi_desc
>   (addresses warnings by kernel test robot <lkp@intel.com>)
> 
> Cristian Marussi (7):
>   firmware: arm_scmi: Introduce packet handling helpers
>   firmware: arm_scmi: Add support for standalone transport drivers
>   firmware: arm_scmi: Make MBOX transport a standalone driver
>   firmware: arm_scmi: Make SMC transport a standalone driver
>   firmware: arm_scmi: Make OPTEE transport a standalone driver
>   firmware: arm_scmi: Make VirtIO transport a standalone driver
>   firmware: arm_scmi: Remove legacy transport-layer code
> 
> Peng Fan (1):
>   firmware: arm_scmi: Introduce setup_shmem_iomap
> 
>  drivers/firmware/arm_scmi/Kconfig             |  20 +-
>  drivers/firmware/arm_scmi/Makefile            |   9 +-
>  drivers/firmware/arm_scmi/common.h            | 184 +++++++++++++----
> -
>  drivers/firmware/arm_scmi/driver.c            | 140 +++++--------
>  drivers/firmware/arm_scmi/msg.c               |  34 +++-
>  .../{mailbox.c => scmi_transport_mailbox.c}   |  69 ++++---
>  .../{optee.c => scmi_transport_optee.c}       | 124 +++++-------
>  .../arm_scmi/{smc.c => scmi_transport_smc.c}  |  58 +++---
>  .../{virtio.c => scmi_transport_virtio.c}     | 103 +++++-----
>  drivers/firmware/arm_scmi/shmem.c             |  85 ++++++--
>  10 files changed, 468 insertions(+), 358 deletions(-)  rename
> drivers/firmware/arm_scmi/{mailbox.c => scmi_transport_mailbox.c}
> (87%)  rename drivers/firmware/arm_scmi/{optee.c =>
> scmi_transport_optee.c} (89%)  rename
> drivers/firmware/arm_scmi/{smc.c => scmi_transport_smc.c} (87%)
> rename drivers/firmware/arm_scmi/{virtio.c => scmi_transport_virtio.c}
> (94%)
> 
> --
> 2.45.2
> 

Re: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet handling helpers

[Cristian Marussi]

On Thu, Jul 11, 2024 at 10:43:23AM +0000, Peng Fan wrote:
> > Subject: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet
> > handling helpers
> > 

Hi Peng,

thanks for having a look.

> > Introduce a pair of structures initialized to contain all the existing
> > packet handling helpers, both for transports based on shared memory
> > and messages.
> > 
> > No functional change.
> > 
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > v1 --> v2
> > - fixed commit message
> > ---
> ......
> 
> > d33a704e5814..f4ba38afe0bb 100644
> > --- a/drivers/firmware/arm_scmi/msg.c
> > +++ b/drivers/firmware/arm_scmi/msg.c
> > @@ -4,8 +4,8 @@
> >   *
> >   * Derived from shm.c.
> >   *
> > - * Copyright (C) 2019-2021 ARM Ltd.
> > - * Copyright (C) 2020-2021 OpenSynergy GmbH
> > + * Copyright (C) 2019-2024 ARM Ltd.
> > + * Copyright (C) 2020-2024 OpenSynergy GmbH
> 
> Nitpick: OpenSynergy year should be kept unchanged?
> 
> Otherwise looks good:
> Reviewed-by: Peng Fan <peng.fan@nxp.com>

Yeah, I am not sure how to go around years of Copyrights...moreover I
received some auto-responder email from OpenSynergy saying thay have
been acquired by Qualcomm....I suppose I have to stick anyway with the
original autorship/copyright.

Thanks,
Cristian

Re: [PATCH v2 3/8] firmware: arm_scmi: Add support for standalone transport drivers

[Cristian Marussi]

On Thu, Jul 11, 2024 at 12:54:51PM +0000, Peng Fan wrote:
> > Subject: [PATCH v2 3/8] firmware: arm_scmi: Add support for
> > standalone transport drivers
> > 

Hi Peng,

> > Extend the core SCMI stack with structures and methods to allow for
> > transports to be split out as standalone drivers, while still supporting
> > old style transports, defined as built into the SCMI core stack.
> > 
> > No functional change.
> > 
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > NOTE: old style transport support will be removed later in this series.
> > 
> > v1 --> v2
> > - fixed comit message
> > ---
> >  drivers/firmware/arm_scmi/common.h | 84
> > ++++++++++++++++++++++++++++++
> > drivers/firmware/arm_scmi/driver.c | 44 +++++++++++++++-
> >  drivers/firmware/arm_scmi/msg.c    |  5 ++
> >  drivers/firmware/arm_scmi/shmem.c  |  5 ++
> >  4 files changed, 136 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/firmware/arm_scmi/common.h
> > b/drivers/firmware/arm_scmi/common.h
> > index 8e5751aaa600..4af06810eb39 100644
> > --- a/drivers/firmware/arm_scmi/common.h
> > +++ b/drivers/firmware/arm_scmi/common.h
> > @@ -349,6 +349,8 @@ struct scmi_shared_mem_operations {
> >  				     bool tx, struct resource *res);  };
> > 
> > +const struct scmi_shared_mem_operations
> > +*scmi_shared_mem_operations_get(void);
> > +
> >  /* declarations for message passing transports */  struct
> > scmi_msg_payld;
> > 
> > @@ -376,6 +378,88 @@ struct scmi_message_operations {
> >  				   size_t max_len, struct scmi_xfer
> > *xfer);  };
> > 
> > +const struct scmi_message_operations
> > +*scmi_message_operations_get(void);
> > +
> > +/**
> > + * struct scmi_transport_core_operations  - Transpoert core
> > operations
> > + *
> > + * @bad_message_trace: An helper to report a
> > malformed/unexpected
> > +message
> > + * @rx_callback: Callback to report received messages
> > + * @shmem: Datagram operations for shared memory based
> > transports
> > + * @msg: Datagram operations for message based transports  */
> > struct
> > +scmi_transport_core_operations {
> > +	void (*bad_message_trace)(struct scmi_chan_info *cinfo,
> > +				  u32 msg_hdr, enum scmi_bad_msg
> > err);
> > +	void (*rx_callback)(struct scmi_chan_info *cinfo, u32 msg_hdr,
> > +			    void *priv);
> > +	const struct scmi_shared_mem_operations *shmem;
> > +	const struct scmi_message_operations *msg; };
> > +
> > +/**
> > + * struct scmi_transport  - A structure representing a configured
> > +transport
> > + *
> > + * @supplier: Device representimng the transport and acting as a
> > supplier for
> > + *	      the core SCMI stack
> > + * @desc: Transport descriptor
> > + * @core_ops: A pointer to a pointer used by the core SCMI stack to
> > make the
> > + *	      core transport operations accessible to the transports.
> > + */
> > +struct scmi_transport {
> > +	struct device *supplier;
> > +	const struct scmi_desc *desc;
> > +	struct scmi_transport_core_operations **core_ops; };
> > +
> > +#define DEFINE_SCMI_TRANSPORT_DRIVER(__trans, __match_table,
> > __core_ptr)\
> > +static int __trans##_probe(struct platform_device *pdev)		\
> > +{
> > 	\
> > +	struct scmi_transport *scmi_trans;
> > 	\
> > +	struct platform_device *scmi_pdev;
> > 	\
> > +	struct device *dev = &pdev->dev;				\
> > +
> > 	\
> > +	scmi_trans = devm_kzalloc(dev, sizeof(*scmi_trans),
> > GFP_KERNEL);\
> > +	if (!scmi_trans)						\
> > +		return -ENOMEM;
> > 		\
> > +
> > 	\
> > +	scmi_pdev = devm_kzalloc(dev, sizeof(*scmi_pdev),
> > GFP_KERNEL);	\
> > +	if (!scmi_pdev)
> > 	\
> > +		return -ENOMEM;
> > 		\
> > +
> > 	\
> > +	scmi_trans->supplier = dev;
> > 	\
> > +	scmi_trans->desc = &__trans##_desc;
> > 	\
> > +	scmi_trans->core_ops = __core_ptr;
> > 	\
> > +
> > 	\
> > +	scmi_pdev->name = "arm-scmi";
> > 	\
> > +	scmi_pdev->id = PLATFORM_DEVID_AUTO;
> > 		\
> > +	scmi_pdev->dev.platform_data = scmi_trans;
> > 	\
> > +
> > 	\
> > +	device_set_of_node_from_dev(&scmi_pdev->dev, dev);
> > 	\
> > +
> > 	\
> > +	dev_set_drvdata(dev, scmi_pdev);
> > 	\
> > +
> > 	\
> > +	return platform_device_register(scmi_pdev);
> > 	\
> > +}
> > 	\
> > +
> > 	\
> > +static void __trans##_remove(struct platform_device *pdev)
> > 	\
> > +{
> > 	\
> > +	struct platform_device *scmi_pdev;
> > 	\
> > +
> > 	\
> > +	scmi_pdev = dev_get_drvdata(&pdev->dev);
> > 	\
> > +
> > 	\
> > +	platform_device_unregister(scmi_pdev);
> > 	\
> > +}
> > 	\
> > +
> > 	\
> > +static struct platform_driver __trans##_driver = {			\
> > +	.driver = {
> > 	\
> > +		   .name = #__trans "_transport",			\
> > +		   .of_match_table = __match_table,
> > 	\
> > +		   },
> > 	\
> > +	.probe = __trans##_probe,
> > 	\
> > +	.remove_new = __trans##_remove,
> > 		\
> > +}
> > +
> >  extern const struct scmi_shared_mem_operations scmi_shmem_ops;
> > extern const struct scmi_message_operations scmi_msg_ops;
> > 
> > diff --git a/drivers/firmware/arm_scmi/driver.c
> > b/drivers/firmware/arm_scmi/driver.c
> > index 6b6957f4743f..a1892d4d8c69 100644
> > --- a/drivers/firmware/arm_scmi/driver.c
> > +++ b/drivers/firmware/arm_scmi/driver.c
> > @@ -194,6 +194,11 @@ struct scmi_info {
> >  #define bus_nb_to_scmi_info(nb)	container_of(nb, struct
> > scmi_info, bus_nb)
> >  #define req_nb_to_scmi_info(nb)	container_of(nb, struct
> > scmi_info, dev_req_nb)
> > 
> > +static struct scmi_transport_core_operations scmi_trans_core_ops = {
> > +	.bad_message_trace = scmi_bad_message_trace,
> > +	.rx_callback = scmi_rx_callback,
> > +};
> > +
> >  static unsigned long
> >  scmi_vendor_protocol_signature(unsigned int protocol_id, char
> > *vendor_id,
> >  			       char *sub_vendor_id, u32 impl_ver) @@
> > -2950,6 +2955,28 @@ static int scmi_debugfs_raw_mode_setup(struct
> > scmi_info *info)
> >  	return ret;
> >  }
> > 
> > +static const struct scmi_desc *scmi_transport_lookup(struct device
> > +*dev) {
> > +	struct scmi_transport *trans;
> > +
> > +	trans = dev_get_platdata(dev);
> > +	if (!trans || !trans->desc || !trans->supplier || !trans-
> > >core_ops)
> > +		return NULL;
> > +
> > +	if (!device_link_add(dev, trans->supplier,
> > DL_FLAG_AUTOREMOVE_CONSUMER)) {
> 
> Just wonder why this is needed?

Oh, that is absolutely needed, because it unleashes the power of device_link ! 
(..and I jus discovered this myself only recently :P ...)..if I got your
question right....

...and that, together with the AUTOREMOVE_CONSUMER flag, means in other words
that the transport device is linked as a supplier to the consumer SCMI core
stack devices, and as a consequence you are absolutely free to abruptly
unload/unbind the transport driver at any time and be sure that before that
can happen the full SCMI stack will be FULLY UNBOUND too...so stopping any
SCMI communication before the transport module is unloaded/unbound....

...and this, more importantly, happens without ME having to write ANY line of
code :P....just thanks to the device_link core magic...

...or at least this is my understanding and 

> > +		dev_err(dev,
> > +			"Adding link to supplier transport device
> > failed\n");
> > +		return NULL;
> > +	}
> > +
> > +	/* Provide core transport ops */
> > +	*trans->core_ops = &scmi_trans_core_ops;
> > +
> > +	dev_info(dev, "Using %s\n", dev_driver_string(trans->supplier));
> > +
> > +	return trans->desc;
> > +}
> > +
> >  static int scmi_probe(struct platform_device *pdev)  {
> >  	int ret;
> > @@ -2962,8 +2989,14 @@ static int scmi_probe(struct
> > platform_device *pdev)
> >  	struct device_node *child, *np = dev->of_node;
> > 
> >  	desc = of_device_get_match_data(dev);
> > -	if (!desc)
> > -		return -EINVAL;
> > +	if (!desc) {
> > +		desc = scmi_transport_lookup(dev);
> 
> from the code, It is not actually a lookup operation.
> How about scmi_transport_setup?
> 

Oh, yes...funny thing is that it is how exactly I DID called this
function initially....then I spotted that there was already a similar
__scmi_trancport_setup() helper in the legacy code that I removed, so I
tried to use another more distinct name....I could go back to
scmi_transport_setup indeed..

Thanks,
Cristian

Re: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a standalone driver

[Cristian Marussi]

On Thu, Jul 11, 2024 at 12:57:46PM +0000, Peng Fan wrote:
> > Subject: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a
> > standalone driver
> > 
> > Make SCMI OPTEE transport a standalone driver that can be optionally
> > loaded as a module.
> > 
> > CC: Etienne Carriere <etienne.carriere@foss.st.com>
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > v1 --> v2
> > - handle platform_driver_register() failures
> > ---
> >  drivers/firmware/arm_scmi/Kconfig             |  6 +-
> >  drivers/firmware/arm_scmi/Makefile            |  2 +-
> >  drivers/firmware/arm_scmi/common.h            |  3 -
> >  drivers/firmware/arm_scmi/driver.c            |  3 -
> >  .../{optee.c => scmi_transport_optee.c}       | 91 ++++++++++---------
> >  5 files changed, 52 insertions(+), 53 deletions(-)  rename
> > drivers/firmware/arm_scmi/{optee.c => scmi_transport_optee.c} (90%)
> > 
> > diff --git a/drivers/firmware/arm_scmi/Kconfig
> > b/drivers/firmware/arm_scmi/Kconfig
> > index a4d44ef8bf45..def7e3f09356 100644
> > --- a/drivers/firmware/arm_scmi/Kconfig
> > +++ b/drivers/firmware/arm_scmi/Kconfig
> > @@ -89,8 +89,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
> >  	  will be called scmi_transport_mailbox.
> > 
> >  config ARM_SCMI_TRANSPORT_OPTEE
> > -	bool "SCMI transport based on OP-TEE service"
> > -	depends on OPTEE=y || OPTEE=ARM_SCMI_PROTOCOL
> > +	tristate "SCMI transport based on OP-TEE service"
> > +	depends on OPTEE
> >  	select ARM_SCMI_HAVE_TRANSPORT
> >  	select ARM_SCMI_HAVE_SHMEM
> >  	select ARM_SCMI_HAVE_MSG
> > @@ -100,6 +100,8 @@ config ARM_SCMI_TRANSPORT_OPTEE
> > 
> >  	  If you want the ARM SCMI PROTOCOL stack to include
> > support for a
> >  	  transport based on OP-TEE SCMI service, answer Y.
> > +	  This driver can also be built as a module.  If so, the module
> > +	  will be called scmi_transport_optee.
> > 
> >  config ARM_SCMI_TRANSPORT_SMC
> >  	tristate "SCMI transport based on SMC"
> > diff --git a/drivers/firmware/arm_scmi/Makefile
> > b/drivers/firmware/arm_scmi/Makefile
> > index 6868a47fa4ab..b04119ce972f 100644
> > --- a/drivers/firmware/arm_scmi/Makefile
> > +++ b/drivers/firmware/arm_scmi/Makefile
> > @@ -7,13 +7,13 @@ scmi-driver-
> > $(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
> > -scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
> > scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o
> > system.o voltage.o powercap.o  scmi-protocols-y += pinctrl.o  scmi-
> > module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
> > 
> >  obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) +=
> > scmi_transport_smc.o
> >  obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) +=
> > scmi_transport_mailbox.o
> > +obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) +=
> > scmi_transport_optee.o
> > 
> >  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
> >  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o diff --git
> > a/drivers/firmware/arm_scmi/common.h
> > b/drivers/firmware/arm_scmi/common.h
> > index edb786cde25c..0ce1d804b3fc 100644
> > --- a/drivers/firmware/arm_scmi/common.h
> > +++ b/drivers/firmware/arm_scmi/common.h
> > @@ -289,9 +289,6 @@ int
> > scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info
> > *cinfo,  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO  extern const
> > struct scmi_desc scmi_virtio_desc;  #endif -#ifdef
> > CONFIG_ARM_SCMI_TRANSPORT_OPTEE -extern const struct
> > scmi_desc scmi_optee_desc; -#endif
> > 
> >  void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr,
> > void *priv);
> > 
> > diff --git a/drivers/firmware/arm_scmi/driver.c
> > b/drivers/firmware/arm_scmi/driver.c
> > index b14c5326930a..67b416c7f2f5 100644
> > --- a/drivers/firmware/arm_scmi/driver.c
> > +++ b/drivers/firmware/arm_scmi/driver.c
> > @@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
> > 
> >  /* Each compatible listed below must have descriptor associated with
> > it */  static const struct of_device_id scmi_of_match[] = { -#ifdef
> > CONFIG_ARM_SCMI_TRANSPORT_OPTEE
> > -	{ .compatible = "linaro,scmi-optee", .data =
> > &scmi_optee_desc },
> > -#endif
> >  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
> >  	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
> > #endif diff --git a/drivers/firmware/arm_scmi/optee.c
> > b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> > similarity index 90%
> > rename from drivers/firmware/arm_scmi/optee.c rename to
> > drivers/firmware/arm_scmi/scmi_transport_optee.c
> > index 99f3b0bfb956..7a16c8d3e213 100644
> > --- a/drivers/firmware/arm_scmi/optee.c
> > +++ b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> > @@ -1,6 +1,6 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  /*
> > - * Copyright (C) 2019-2021 Linaro Ltd.
> > + * Copyright (C) 2019-2024 Linaro Ltd.
> 
> This should be kept unchanged?

Not sure, like I said previously, how to go about years.
Thanks,
Cristian

Re: [PATCH 0/8] Make SCMI transport as standalone drivers

[Cristian Marussi]

On Thu, Jul 11, 2024 at 01:26:16PM +0000, Peng Fan wrote:
> > Subject: [PATCH 0/8] Make SCMI transport as standalone drivers
> 
> You may need use V2 here :)

...oh damn :P

> > 
> > Hi all,
> > 
> > Till now the SCMI transport layer was being built embedded into in the
> > core SCMI stack.
> > 
> > Some of these transports, despite being currently part of the main
> > SCMI module, are indeed also registered with different subsystems like
> > optee or virtio, and actively probed also by those: this led to a few
> > awkward and convoluted tricks to properly handle such interactions at
> > boot time in the SCMI stack.
> > 
> > Moreover some partner expressed the desire to be able to fully
> > modularize the transports components.
> > 
> > This series aim to make all such transports as standalone drivers that
> > can be optionally loaded as modules.
> > 
> > In order to do this, at first some new mechanism is introduced to
> > support this new capability while maintaining, in parallel, the old
> > legacy embedded transports; then each transport, one by one, is
> > transitioned to be a standalone driver and finally the old legacy
> > support for embedded transport is removed.
> > 
> > Patch [1/8] is a mostly unrelated (but much needed) clean-up from
> > Peng, which I included in this series to avoid conflicts at merge.
> > 
> > Patch [2/8] simply collects the existing datagram manipulation helpers
> > in a pair of function pointers structures, in preparation for later reworks.
> > 
> > Patch [3/8] adds the bulk of the new logic to the core SCMI stack and
> > then each existing transport is transitioned to be a standalone driver in
> > patches 4,5,6,7 while shuffling around the compatibles. (no DT change
> > is needed of curse for backward compatibility) While doing this I kept
> > the module authorship in line with the main
> > author(S) as spitted out by git-blame.
> > 
> > Finally patch [8/8] removes all the legacy dead code from the core
> > SCMI stack.
> > 
> > No new symbol EXPORT has been added.
> > 
> > The new transport drivers have been tested, as built-in and LKM, as
> > follows:
> > 
> > - mailbox on JUNO
> > - virtio on emulation
> > - optee on QEMU/optee using Linaro setup
> > 
> > Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> > testing commands, replies, delayed responses and notification.
> > 
> > Multiple virtual SCMI instances support has been tested too.
> > 
> > SMC has NOT been tested/exercised at run-time, only compile-tested.
> > (due to lack of hardware)
> > 
> > Note that in this new setup, all the probe deferral and retries between
> > the SCMI core stack and the transports has been removed, since no
> > more needed.
> > 
> > Moreover the new drivers have been tested also with a fully
> > modularized SCMI stack, i.e.:
> > 
> >   scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor
> > modules ]
> > 
> > ToBeDone:
> >  - completely remove any dependency at build time at the Kconfig level
> > between
> >    the SCMI core and the transport drivers: so that the transports will be
> >    dependent only on the related subsystems (optee/virtio/mailbox/smc)
> >    (easy to be done but maybe it is not worth...)
> >  - integrate per-platform transport configuration capabilities
> >    (max_rx_timeout_ms & friends..)
> > 
> > Based on sudeep/for-next/scmi/updates.
> > 
> > Any feedback, and especially testing (:D) is welcome.
> > 
> 
> For the v2 patchset:
> Tested-by: Peng Fan <peng.fan@nxp.com>  #i.MX95-19x19-EVK
> 

Thanks a lot for the review and testing,

Cristian

Re: [PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap

[kernel test robot]

Hi Cristian,

kernel test robot noticed the following build warnings:

[auto build test WARNING on soc/for-next]
[also build test WARNING on next-20240712]
[cannot apply to linus/master v6.10-rc7]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Cristian-Marussi/firmware-arm_scmi-Introduce-setup_shmem_iomap/20240711-062033
base:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
patch link:    https://lore.kernel.org/r/20240710173153.4060457-2-cristian.marussi%40arm.com
patch subject: [PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap
config: arm64-randconfig-r132-20240712 (https://download.01.org/0day-ci/archive/20240713/202407130355.IWguWKJm-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce: (https://download.01.org/0day-ci/archive/20240713/202407130355.IWguWKJm-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407130355.IWguWKJm-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> drivers/firmware/arm_scmi/shmem.c:153:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
   drivers/firmware/arm_scmi/shmem.c:153:31: sparse:     expected void [noderef] __iomem *
   drivers/firmware/arm_scmi/shmem.c:153:31: sparse:     got void *
   drivers/firmware/arm_scmi/shmem.c:156:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
   drivers/firmware/arm_scmi/shmem.c:156:31: sparse:     expected void [noderef] __iomem *
   drivers/firmware/arm_scmi/shmem.c:156:31: sparse:     got void *
   drivers/firmware/arm_scmi/shmem.c:165:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
   drivers/firmware/arm_scmi/shmem.c:165:31: sparse:     expected void [noderef] __iomem *
   drivers/firmware/arm_scmi/shmem.c:165:31: sparse:     got void *
   drivers/firmware/arm_scmi/shmem.c:172:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
   drivers/firmware/arm_scmi/shmem.c:172:31: sparse:     expected void [noderef] __iomem *
   drivers/firmware/arm_scmi/shmem.c:172:31: sparse:     got void *

vim +153 drivers/firmware/arm_scmi/shmem.c

   138	
   139	void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
   140					struct device *dev, bool tx,
   141					struct resource *res)
   142	{
   143		struct device_node *shmem __free(device_node);
   144		const char *desc = tx ? "Tx" : "Rx";
   145		int ret, idx = tx ? 0 : 1;
   146		struct device *cdev = cinfo->dev;
   147		struct resource lres = {};
   148		resource_size_t size;
   149		void __iomem *addr;
   150	
   151		shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
   152		if (!shmem)
 > 153			return ERR_PTR(-ENODEV);

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 0/8] Make SCMI transport as standalone drivers

[Florian Fainelli]

On 7/10/24 10:31, Cristian Marussi wrote:
> Hi all,
> 
> Till now the SCMI transport layer was being built embedded into in the core
> SCMI stack.
> 
> Some of these transports, despite being currently part of the main SCMI
> module, are indeed also registered with different subsystems like optee or
> virtio, and actively probed also by those: this led to a few awkward and
> convoluted tricks to properly handle such interactions at boot time in the
> SCMI stack.
> 
> Moreover some partner expressed the desire to be able to fully modularize
> the transports components.
> 
> This series aim to make all such transports as standalone drivers that can
> be optionally loaded as modules.
> 
> In order to do this, at first some new mechanism is introduced to support
> this new capability while maintaining, in parallel, the old legacy embedded
> transports; then each transport, one by one, is transitioned to be a
> standalone driver and finally the old legacy support for embedded transport
> is removed.
> 
> Patch [1/8] is a mostly unrelated (but much needed) clean-up from Peng,
> which I included in this series to avoid conflicts at merge.
> 
> Patch [2/8] simply collects the existing datagram manipulation helpers in a
> pair of function pointers structures, in preparation for later reworks.
> 
> Patch [3/8] adds the bulk of the new logic to the core SCMI stack and then
> each existing transport is transitioned to be a standalone driver in
> patches 4,5,6,7 while shuffling around the compatibles. (no DT change is
> needed of curse for backward compatibility)
> While doing this I kept the module authorship in line with the main
> author(S) as spitted out by git-blame.
> 
> Finally patch [8/8] removes all the legacy dead code from the core SCMI
> stack.
> 
> No new symbol EXPORT has been added.
> 
> The new transport drivers have been tested, as built-in and LKM, as
> follows:
> 
> - mailbox on JUNO
> - virtio on emulation
> - optee on QEMU/optee using Linaro setup
> 
> Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> testing commands, replies, delayed responses and notification.
> 
> Multiple virtual SCMI instances support has been tested too.
> 
> SMC has NOT been tested/exercised at run-time, only compile-tested.
> (due to lack of hardware)
> 
> Note that in this new setup, all the probe deferral and retries between the
> SCMI core stack and the transports has been removed, since no more needed.
> 
> Moreover the new drivers have been tested also with a fully modularized
> SCMI stack, i.e.:
> 
>    scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor modules ]
> 
> ToBeDone:
>   - completely remove any dependency at build time at the Kconfig level between
>     the SCMI core and the transport drivers: so that the transports will be
>     dependent only on the related subsystems (optee/virtio/mailbox/smc)
>     (easy to be done but maybe it is not worth...)
>   - integrate per-platform transport configuration capabilities
>     (max_rx_timeout_ms & friends..)
> 
> Based on sudeep/for-next/scmi/updates.
> 
> Any feedback, and especially testing (:D) is welcome.

Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
-- 
Florian

Re: [PATCH 0/8] Make SCMI transport as standalone drivers

[Etienne CARRIERE]

Hi Cristian, Peng,

On Thursday, July 11, 2024, Cristian Marussi worte:
> On Thu, Jul 11, 2024 at 01:26:16PM +0000, Peng Fan wrote:
> > > Subject: [PATCH 0/8] Make SCMI transport as standalone drivers
> >
> > You may need use V2 here :)
> 
> ...oh damn :P
> 
> > >
> > > Hi all,
> > >
> > > Till now the SCMI transport layer was being built embedded into in the
> > > core SCMI stack.
> > >
> > > Some of these transports, despite being currently part of the main
> > > SCMI module, are indeed also registered with different subsystems like
> > > optee or virtio, and actively probed also by those: this led to a few
> > > awkward and convoluted tricks to properly handle such interactions at
> > > boot time in the SCMI stack.
> > >
> > > Moreover some partner expressed the desire to be able to fully
> > > modularize the transports components.
> > >
> > > This series aim to make all such transports as standalone drivers that
> > > can be optionally loaded as modules.
> > >
> > > In order to do this, at first some new mechanism is introduced to
> > > support this new capability while maintaining, in parallel, the old
> > > legacy embedded transports; then each transport, one by one, is
> > > transitioned to be a standalone driver and finally the old legacy
> > > support for embedded transport is removed.
> > >
> > > Patch [1/8] is a mostly unrelated (but much needed) clean-up from
> > > Peng, which I included in this series to avoid conflicts at merge.
> > >
> > > Patch [2/8] simply collects the existing datagram manipulation helpers
> > > in a pair of function pointers structures, in preparation for later reworks.
> > >
> > > Patch [3/8] adds the bulk of the new logic to the core SCMI stack and
> > > then each existing transport is transitioned to be a standalone driver in
> > > patches 4,5,6,7 while shuffling around the compatibles. (no DT change
> > > is needed of curse for backward compatibility) While doing this I kept
> > > the module authorship in line with the main
> > > author(S) as spitted out by git-blame.
> > >
> > > Finally patch [8/8] removes all the legacy dead code from the core
> > > SCMI stack.
> > >
> > > No new symbol EXPORT has been added.
> > >
> > > The new transport drivers have been tested, as built-in and LKM, as
> > > follows:
> > >
> > > - mailbox on JUNO
> > > - virtio on emulation
> > > - optee on QEMU/optee using Linaro setup
> > >
> > > Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> > > testing commands, replies, delayed responses and notification.
> > >
> > > Multiple virtual SCMI instances support has been tested too.
> > >
> > > SMC has NOT been tested/exercised at run-time, only compile-tested.
> > > (due to lack of hardware)
> > >
> > > Note that in this new setup, all the probe deferral and retries between
> > > the SCMI core stack and the transports has been removed, since no
> > > more needed.
> > >
> > > Moreover the new drivers have been tested also with a fully
> > > modularized SCMI stack, i.e.:
> > >
> > >   scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor
> > > modules ]
> > >
> > > ToBeDone:
> > >  - completely remove any dependency at build time at the Kconfig level
> > > between
> > >    the SCMI core and the transport drivers: so that the transports will be
> > >    dependent only on the related subsystems (optee/virtio/mailbox/smc)
> > >    (easy to be done but maybe it is not worth...)
> > >  - integrate per-platform transport configuration capabilities
> > >    (max_rx_timeout_ms & friends..)
> > >
> > > Based on sudeep/for-next/scmi/updates.
> > >
> > > Any feedback, and especially testing (:D) is welcome.
> > >
> >
> > For the v2 patchset:
> > Tested-by: Peng Fan <peng.fan@nxp.com>  #i.MX95-19x19-EVK
> >
> 
> Thanks a lot for the review and testing,
> 
> Cristian


I've tested this v2 on stm32mp157c-scmi.dts. Using built-in modules
works perfectly.  I've tweaked my platform setup to test the .ko and
modprobe part. It works ok for the probe part but I faced kernel oops
when unloading scmi-module after transport is loaded, used, then unoaded.
The issue I saw is around calls to info->desc->ops->chan_free in
scmi_cleanup_channels(). I wonder if there are some ops that were not
unregistered when transport driver is unloaded.

Aside this, I'll sent few minor comments on few patches of your series.

Best regards,
Etienne

Re: [PATCH v2 3/8] firmware: arm_scmi: Add support for standalone transport drivers

[Etienne CARRIERE]

Hi Cristian,

Few nitpicking comments.

On Wednesday, July 10, 2024, Cristian Marussi wrote:  
> Extend the core SCMI stack with structures and methods to allow for
> transports to be split out as standalone drivers, while still supporting
> old style transports, defined as built into the SCMI core stack.
> 
> No functional change.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
> NOTE: old style transport support will be removed later in this series.
> 
> v1 --> v2
> - fixed comit message
> ---
>  drivers/firmware/arm_scmi/common.h | 84 ++++++++++++++++++++++++++++++
>  drivers/firmware/arm_scmi/driver.c | 44 +++++++++++++++-
>  drivers/firmware/arm_scmi/msg.c    |  5 ++
>  drivers/firmware/arm_scmi/shmem.c  |  5 ++
>  4 files changed, 136 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
> index 8e5751aaa600..4af06810eb39 100644
> --- a/drivers/firmware/arm_scmi/common.h
> +++ b/drivers/firmware/arm_scmi/common.h
> @@ -349,6 +349,8 @@ struct scmi_shared_mem_operations {
>                                       bool tx, struct resource *res);
>  };
>  
> +const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void);
> +
>  /* declarations for message passing transports */
>  struct scmi_msg_payld;
>  
> @@ -376,6 +378,88 @@ struct scmi_message_operations {
>                                     size_t max_len, struct scmi_xfer *xfer);
>  };
>  
> +const struct scmi_message_operations *scmi_message_operations_get(void);
> +
> +/**
> + * struct scmi_transport_core_operations  - Transpoert core operations
> + *
> + * @bad_message_trace: An helper to report a malformed/unexpected message
> + * @rx_callback: Callback to report received messages
> + * @shmem: Datagram operations for shared memory based transports
> + * @msg: Datagram operations for message based transports
> + */
> +struct scmi_transport_core_operations {
> +       void (*bad_message_trace)(struct scmi_chan_info *cinfo,
> +                                 u32 msg_hdr, enum scmi_bad_msg err);
> +       void (*rx_callback)(struct scmi_chan_info *cinfo, u32 msg_hdr,
> +                           void *priv);
> +       const struct scmi_shared_mem_operations *shmem;
> +       const struct scmi_message_operations *msg;
> +};
> +
> +/**
> + * struct scmi_transport  - A structure representing a configured transport
> + *
> + * @supplier: Device representimng the transport and acting as a supplier for

typo: s/representimng/representing/

> + *           the core SCMI stack
> + * @desc: Transport descriptor
> + * @core_ops: A pointer to a pointer used by the core SCMI stack to make the
> + *           core transport operations accessible to the transports.
> + */
> +struct scmi_transport {
> +       struct device *supplier;
> +       const struct scmi_desc *desc;
> +       struct scmi_transport_core_operations **core_ops;
> +};
> +
> +#define DEFINE_SCMI_TRANSPORT_DRIVER(__trans, __match_table, __core_ptr)\
> +static int __trans##_probe(struct platform_device *pdev)               \
> +{                                                                      \
> +       struct scmi_transport *scmi_trans;                              \
> +       struct platform_device *scmi_pdev;                              \
> +       struct device *dev = &pdev->dev;                                \
> +                                                                       \
> +       scmi_trans = devm_kzalloc(dev, sizeof(*scmi_trans), GFP_KERNEL);\
> +       if (!scmi_trans)                                                \
> +               return -ENOMEM;                                         \
> +                                                                       \
> +       scmi_pdev = devm_kzalloc(dev, sizeof(*scmi_pdev), GFP_KERNEL);  \
> +       if (!scmi_pdev)                                                 \
> +               return -ENOMEM;                                         \
> +                                                                       \
> +       scmi_trans->supplier = dev;                                     \
> +       scmi_trans->desc = &__trans##_desc;                             \

It's a bit weird the scmi_desc shall be specifically labeled __trans##_desc
in the transport driver source file while match table and transport core
operations instances references are passed as arguments. I think it's 
worth having the scmi_desc label also passed as an argument to
DEFINE_SCMI_TRANSPORT_DRIVER() macro.

> +       scmi_trans->core_ops = __core_ptr;                              \
> +                                                                       \
> +       scmi_pdev->name = "arm-scmi";                                   \
> +       scmi_pdev->id = PLATFORM_DEVID_AUTO;                            \
> +       scmi_pdev->dev.platform_data = scmi_trans;                      \
> +                                                                       \
> +       device_set_of_node_from_dev(&scmi_pdev->dev, dev);              \
> +                                                                       \
> +       dev_set_drvdata(dev, scmi_pdev);                                \
> +                                                                       \
> +       return platform_device_register(scmi_pdev);                     \
> +}                                                                      \
> +                                                                       \
> +static void __trans##_remove(struct platform_device *pdev)             \
> +{                                                                      \
> +       struct platform_device *scmi_pdev;                              \
> +                                                                       \
> +       scmi_pdev = dev_get_drvdata(&pdev->dev);                        \
> +                                                                       \
> +       platform_device_unregister(scmi_pdev);                          \
> +}                                                                      \
> +                                                                       \
> +static struct platform_driver __trans##_driver = {                     \

Same here. I think __trans##_driver label should be also explicitly
passed as an argument to DEFINE_SCMI_TRANSPORT_DRIVER().

BR,
Etienne




> +       .driver = {                                                     \
> +                  .name = #__trans "_transport",                        \
> +                  .of_match_table = __match_table,                      \
> +                  },                                                    \
> +       .probe = __trans##_probe,                                       \
> +       .remove_new = __trans##_remove,                                 \
> +}
> +
>  extern const struct scmi_shared_mem_operations scmi_shmem_ops;
>  extern const struct scmi_message_operations scmi_msg_ops;
>  
> diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
> index 6b6957f4743f..a1892d4d8c69 100644
> --- a/drivers/firmware/arm_scmi/driver.c
> +++ b/drivers/firmware/arm_scmi/driver.c
> @@ -194,6 +194,11 @@ struct scmi_info {
>  #define bus_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, bus_nb)
>  #define req_nb_to_scmi_info(nb) container_of(nb, struct scmi_info, dev_req_nb)
>  
> +static struct scmi_transport_core_operations scmi_trans_core_ops = {
> +       .bad_message_trace = scmi_bad_message_trace,
> +       .rx_callback = scmi_rx_callback,
> +};
> +
>  static unsigned long
>  scmi_vendor_protocol_signature(unsigned int protocol_id, char *vendor_id,
>                                 char *sub_vendor_id, u32 impl_ver)
> @@ -2950,6 +2955,28 @@ static int scmi_debugfs_raw_mode_setup(struct scmi_info *info)
>          return ret;
>  }
>  
> +static const struct scmi_desc *scmi_transport_lookup(struct device *dev)
> +{
> +       struct scmi_transport *trans;
> +
> +       trans = dev_get_platdata(dev);
> +       if (!trans || !trans->desc || !trans->supplier || !trans->core_ops)
> +               return NULL;
> +
> +       if (!device_link_add(dev, trans->supplier, DL_FLAG_AUTOREMOVE_CONSUMER)) {
> +               dev_err(dev,
> +                       "Adding link to supplier transport device failed\n");
> +               return NULL;
> +       }
> +
> +       /* Provide core transport ops */
> +       *trans->core_ops = &scmi_trans_core_ops;
> +
> +       dev_info(dev, "Using %s\n", dev_driver_string(trans->supplier));
> +
> +       return trans->desc;
> +}
> +
>  static int scmi_probe(struct platform_device *pdev)
>  {
>          int ret;
> @@ -2962,8 +2989,14 @@ static int scmi_probe(struct platform_device *pdev)
>          struct device_node *child, *np = dev->of_node;
>  
>          desc = of_device_get_match_data(dev);
> -       if (!desc)
> -               return -EINVAL;
> +       if (!desc) {
> +               desc = scmi_transport_lookup(dev);
> +               if (!desc) {
> +                       err_str = "transport invalid\n";
> +                       ret = -EINVAL;
> +                       goto out_err;
> +               }
> +       }
>  
>          info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
>          if (!info)
> @@ -3130,6 +3163,7 @@ static int scmi_probe(struct platform_device *pdev)
>  clear_ida:
>          ida_free(&scmi_id, info->id);
>  
> +out_err:
>          return dev_err_probe(dev, ret, "%s", err_str);
>  }
>  
> @@ -3321,6 +3355,12 @@ static int __init scmi_driver_init(void)
>          if (ret)
>                  return ret;
>  
> +       if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_SHMEM))
> +               scmi_trans_core_ops.shmem = scmi_shared_mem_operations_get();
> +
> +       if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_MSG))
> +               scmi_trans_core_ops.msg = scmi_message_operations_get();
> +
>          if (IS_ENABLED(CONFIG_ARM_SCMI_NEED_DEBUGFS))
>                  scmi_top_dentry = scmi_debugfs_init();
>  
> diff --git a/drivers/firmware/arm_scmi/msg.c b/drivers/firmware/arm_scmi/msg.c
> index f4ba38afe0bb..0bed1d2825af 100644
> --- a/drivers/firmware/arm_scmi/msg.c
> +++ b/drivers/firmware/arm_scmi/msg.c
> @@ -118,3 +118,8 @@ const struct scmi_message_operations scmi_msg_ops = {
>          .fetch_response = msg_fetch_response,
>          .fetch_notification = msg_fetch_notification,
>  };
> +
> +const struct scmi_message_operations *scmi_message_operations_get(void)
> +{
> +       return &scmi_msg_ops;
> +}
> diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
> index 208a289642c3..b1fc0c31495b 100644
> --- a/drivers/firmware/arm_scmi/shmem.c
> +++ b/drivers/firmware/arm_scmi/shmem.c
> @@ -187,3 +187,8 @@ const struct scmi_shared_mem_operations scmi_shmem_ops = {
>          .channel_intr_enabled = shmem_channel_intr_enabled,
>          .setup_iomap = shmem_setup_iomap,
>  };
> +
> +const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void)
> +{
> +       return &scmi_shmem_ops;
> +}
> --
> 2.45.2
> 

Re: [PATCH v2 4/8] firmware: arm_scmi: Make MBOX transport a standalone driver

[Etienne CARRIERE]

Hi Cristian,

On Wednesday, July 10, 2024, Cristian Marussi wrote:
> Make SCMI mailbox transport a standalne driver that can be optionally
> loaded as a module.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
>  drivers/firmware/arm_scmi/Kconfig             |  4 +-
>  drivers/firmware/arm_scmi/Makefile            |  3 +-
>  drivers/firmware/arm_scmi/common.h            |  3 --
>  drivers/firmware/arm_scmi/driver.c            |  3 --
>  .../{mailbox.c => scmi_transport_mailbox.c}   | 44 +++++++++++++------
>  5 files changed, 36 insertions(+), 21 deletions(-)
>  rename drivers/firmware/arm_scmi/{mailbox.c => scmi_transport_mailbox.c} (88%)
> 
> diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
> index aa5842be19b2..135e34aefd70 100644
> --- a/drivers/firmware/arm_scmi/Kconfig
> +++ b/drivers/firmware/arm_scmi/Kconfig
> @@ -75,7 +75,7 @@ config ARM_SCMI_HAVE_MSG
>            available.
>  
>  config ARM_SCMI_TRANSPORT_MAILBOX
> -       bool "SCMI transport based on Mailbox"
> +       tristate "SCMI transport based on Mailbox"
>          depends on MAILBOX
>          select ARM_SCMI_HAVE_TRANSPORT
>          select ARM_SCMI_HAVE_SHMEM
> @@ -85,6 +85,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
>  
>            If you want the ARM SCMI PROTOCOL stack to include support for a
>            transport based on mailboxes, answer Y.
> +         This driver can also be built as a module.  If so, the module

Nitpicking: replace the 2 space char before "if so," with a single one?
Applies also to patch 5/8, 6/8 and 7/8.

Other wise LGTM , but my comment on patch 3/8 that would affect
use of DEFINE_SCMI_TRANSPORT_DRIVER() in patch 5 to 7.


br,
etienne

> +         will be called scmi_transport_mailbox.
>  
>  config ARM_SCMI_TRANSPORT_OPTEE
>          bool "SCMI transport based on OP-TEE service"
> (snip)

Re: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet handling helpers

[Etienne CARRIERE]

Hi,

On Thursday, July 11, 2024, Peng Fan wrote:
> > Subject: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet
> > handling helpers
> >
> > Introduce a pair of structures initialized to contain all the existing
> > packet handling helpers, both for transports based on shared memory
> > and messages.
> >
> > No functional change.
> >
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > v1 --> v2
> > - fixed commit message
> > ---
> ......
> 
> > d33a704e5814..f4ba38afe0bb 100644
> > --- a/drivers/firmware/arm_scmi/msg.c
> > +++ b/drivers/firmware/arm_scmi/msg.c
> > @@ -4,8 +4,8 @@
> >   *
> >   * Derived from shm.c.
> >   *
> > - * Copyright (C) 2019-2021 ARM Ltd.
> > - * Copyright (C) 2020-2021 OpenSynergy GmbH
> > + * Copyright (C) 2019-2024 ARM Ltd.
> > + * Copyright (C) 2020-2024 OpenSynergy GmbH
> 
> Nitpick: OpenSynergy year should be kept unchanged?

I agree. Copyright dates on original non-Arm contributors should
not be changed, here and in patch 5/8, 6/8 and 7/8.

> 
> Otherwise looks good:
> Reviewed-by: Peng Fan <peng.fan@nxp.com>

Re: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet handling helpers

[Cristian Marussi]

On Tue, Jul 23, 2024 at 01:41:19PM +0000, Etienne CARRIERE wrote:
> Hi,
> 
> On Thursday, July 11, 2024, Peng Fan wrote:
> > > Subject: [PATCH v2 2/8] firmware: arm_scmi: Introduce packet
> > > handling helpers
> > >
> > > Introduce a pair of structures initialized to contain all the existing
> > > packet handling helpers, both for transports based on shared memory
> > > and messages.
> > >
> > > No functional change.
> > >
> > > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > > ---
> > > v1 --> v2
> > > - fixed commit message
> > > ---
> > ......
> > 
> > > d33a704e5814..f4ba38afe0bb 100644
> > > --- a/drivers/firmware/arm_scmi/msg.c
> > > +++ b/drivers/firmware/arm_scmi/msg.c
> > > @@ -4,8 +4,8 @@
> > >   *
> > >   * Derived from shm.c.
> > >   *
> > > - * Copyright (C) 2019-2021 ARM Ltd.
> > > - * Copyright (C) 2020-2021 OpenSynergy GmbH
> > > + * Copyright (C) 2019-2024 ARM Ltd.
> > > + * Copyright (C) 2020-2024 OpenSynergy GmbH
> > 
> > Nitpick: OpenSynergy year should be kept unchanged?
> 

Hi Etienne, Peng

> I agree. Copyright dates on original non-Arm contributors should
> not be changed, here and in patch 5/8, 6/8 and 7/8.
> 

Agreed. Thanks for the clarification, I was not sure how to handle such
old copyrigths....I have fixed alreay all of these Copy for V3.

Thanks,
Cristian

Re: [PATCH v2 3/8] firmware: arm_scmi: Add support for standalone transport drivers

[Cristian Marussi]

On Tue, Jul 23, 2024 at 01:39:41PM +0000, Etienne CARRIERE wrote:
> Hi Cristian,
> 
> Few nitpicking comments.
> 
> On Wednesday, July 10, 2024, Cristian Marussi wrote:  
> > Extend the core SCMI stack with structures and methods to allow for
> > transports to be split out as standalone drivers, while still supporting
> > old style transports, defined as built into the SCMI core stack.
> > 
> > No functional change.
> > 
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > NOTE: old style transport support will be removed later in this series.
> > 
> > v1 --> v2
> > - fixed comit message
> > ---
> >  drivers/firmware/arm_scmi/common.h | 84 ++++++++++++++++++++++++++++++
> >  drivers/firmware/arm_scmi/driver.c | 44 +++++++++++++++-
> >  drivers/firmware/arm_scmi/msg.c    |  5 ++
> >  drivers/firmware/arm_scmi/shmem.c  |  5 ++
> >  4 files changed, 136 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
> > index 8e5751aaa600..4af06810eb39 100644
> > --- a/drivers/firmware/arm_scmi/common.h
> > +++ b/drivers/firmware/arm_scmi/common.h
> > @@ -349,6 +349,8 @@ struct scmi_shared_mem_operations {
> >                                       bool tx, struct resource *res);
> >  };
> >  
> > +const struct scmi_shared_mem_operations *scmi_shared_mem_operations_get(void);
> > +
> >  /* declarations for message passing transports */
> >  struct scmi_msg_payld;
> >  
> > @@ -376,6 +378,88 @@ struct scmi_message_operations {
> >                                     size_t max_len, struct scmi_xfer *xfer);
> >  };
> >  
> > +const struct scmi_message_operations *scmi_message_operations_get(void);
> > +
> > +/**
> > + * struct scmi_transport_core_operations  - Transpoert core operations
> > + *
> > + * @bad_message_trace: An helper to report a malformed/unexpected message
> > + * @rx_callback: Callback to report received messages
> > + * @shmem: Datagram operations for shared memory based transports
> > + * @msg: Datagram operations for message based transports
> > + */
> > +struct scmi_transport_core_operations {
> > +       void (*bad_message_trace)(struct scmi_chan_info *cinfo,
> > +                                 u32 msg_hdr, enum scmi_bad_msg err);
> > +       void (*rx_callback)(struct scmi_chan_info *cinfo, u32 msg_hdr,
> > +                           void *priv);
> > +       const struct scmi_shared_mem_operations *shmem;
> > +       const struct scmi_message_operations *msg;
> > +};
> > +
> > +/**
> > + * struct scmi_transport  - A structure representing a configured transport
> > + *
> > + * @supplier: Device representimng the transport and acting as a supplier for
> 
> typo: s/representimng/representing/
> 

Fixed in V3. (...still to be posted)

> > + *           the core SCMI stack
> > + * @desc: Transport descriptor
> > + * @core_ops: A pointer to a pointer used by the core SCMI stack to make the
> > + *           core transport operations accessible to the transports.
> > + */
> > +struct scmi_transport {
> > +       struct device *supplier;
> > +       const struct scmi_desc *desc;
> > +       struct scmi_transport_core_operations **core_ops;
> > +};
> > +
> > +#define DEFINE_SCMI_TRANSPORT_DRIVER(__trans, __match_table, __core_ptr)\
> > +static int __trans##_probe(struct platform_device *pdev)               \
> > +{                                                                      \
> > +       struct scmi_transport *scmi_trans;                              \
> > +       struct platform_device *scmi_pdev;                              \
> > +       struct device *dev = &pdev->dev;                                \
> > +                                                                       \
> > +       scmi_trans = devm_kzalloc(dev, sizeof(*scmi_trans), GFP_KERNEL);\
> > +       if (!scmi_trans)                                                \
> > +               return -ENOMEM;                                         \
> > +                                                                       \
> > +       scmi_pdev = devm_kzalloc(dev, sizeof(*scmi_pdev), GFP_KERNEL);  \
> > +       if (!scmi_pdev)                                                 \
> > +               return -ENOMEM;                                         \
> > +                                                                       \
> > +       scmi_trans->supplier = dev;                                     \
> > +       scmi_trans->desc = &__trans##_desc;                             \
> 
> It's a bit weird the scmi_desc shall be specifically labeled __trans##_desc
> in the transport driver source file while match table and transport core
> operations instances references are passed as arguments. I think it's 
> worth having the scmi_desc label also passed as an argument to
> DEFINE_SCMI_TRANSPORT_DRIVER() macro.

Yes, I agree, I was unsure about this so I have reworked all of these in
V3 to pass as explicit parameter the driver name and desc name.

> 
> > +       scmi_trans->core_ops = __core_ptr;                              \
> > +                                                                       \
> > +       scmi_pdev->name = "arm-scmi";                                   \
> > +       scmi_pdev->id = PLATFORM_DEVID_AUTO;                            \
> > +       scmi_pdev->dev.platform_data = scmi_trans;                      \
> > +                                                                       \
> > +       device_set_of_node_from_dev(&scmi_pdev->dev, dev);              \
> > +                                                                       \
> > +       dev_set_drvdata(dev, scmi_pdev);                                \
> > +                                                                       \
> > +       return platform_device_register(scmi_pdev);                     \
> > +}                                                                      \
> > +                                                                       \
> > +static void __trans##_remove(struct platform_device *pdev)             \
> > +{                                                                      \
> > +       struct platform_device *scmi_pdev;                              \
> > +                                                                       \
> > +       scmi_pdev = dev_get_drvdata(&pdev->dev);                        \
> > +                                                                       \
> > +       platform_device_unregister(scmi_pdev);                          \
> > +}                                                                      \
> > +                                                                       \
> > +static struct platform_driver __trans##_driver = {                     \
> 
> Same here. I think __trans##_driver label should be also explicitly
> passed as an argument to DEFINE_SCMI_TRANSPORT_DRIVER().
> 

Fixed in V3.

Thanks,
Cristian

Re: [PATCH v2 4/8] firmware: arm_scmi: Make MBOX transport a standalone driver

[Cristian Marussi]

On Tue, Jul 23, 2024 at 01:41:04PM +0000, Etienne CARRIERE wrote:
> Hi Cristian,
> 
> On Wednesday, July 10, 2024, Cristian Marussi wrote:
> > Make SCMI mailbox transport a standalne driver that can be optionally
> > loaded as a module.
> > 
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> >  drivers/firmware/arm_scmi/Kconfig             |  4 +-
> >  drivers/firmware/arm_scmi/Makefile            |  3 +-
> >  drivers/firmware/arm_scmi/common.h            |  3 --
> >  drivers/firmware/arm_scmi/driver.c            |  3 --
> >  .../{mailbox.c => scmi_transport_mailbox.c}   | 44 +++++++++++++------
> >  5 files changed, 36 insertions(+), 21 deletions(-)
> >  rename drivers/firmware/arm_scmi/{mailbox.c => scmi_transport_mailbox.c} (88%)
> > 
> > diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
> > index aa5842be19b2..135e34aefd70 100644
> > --- a/drivers/firmware/arm_scmi/Kconfig
> > +++ b/drivers/firmware/arm_scmi/Kconfig
> > @@ -75,7 +75,7 @@ config ARM_SCMI_HAVE_MSG
> >            available.
> >  
> >  config ARM_SCMI_TRANSPORT_MAILBOX
> > -       bool "SCMI transport based on Mailbox"
> > +       tristate "SCMI transport based on Mailbox"
> >          depends on MAILBOX
> >          select ARM_SCMI_HAVE_TRANSPORT
> >          select ARM_SCMI_HAVE_SHMEM
> > @@ -85,6 +85,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
> >  
> >            If you want the ARM SCMI PROTOCOL stack to include support for a
> >            transport based on mailboxes, answer Y.
> > +         This driver can also be built as a module.  If so, the module
> 
> Nitpicking: replace the 2 space char before "if so," with a single one?
> Applies also to patch 5/8, 6/8 and 7/8.
> 

Fixed in V3.

> Other wise LGTM , but my comment on patch 3/8 that would affect
> use of DEFINE_SCMI_TRANSPORT_DRIVER() in patch 5 to 7.
> 

Yes I reworked the macros params.

Thanks,
Cristian

Re: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a standalone driver

[Cristian Marussi]

On Thu, Jul 11, 2024 at 12:57:46PM +0000, Peng Fan wrote:
> > Subject: [PATCH v2 6/8] firmware: arm_scmi: Make OPTEE transport a
> > standalone driver
> > 
> > Make SCMI OPTEE transport a standalone driver that can be optionally
> > loaded as a module.
> > 
> > CC: Etienne Carriere <etienne.carriere@foss.st.com>
> > Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> > ---
> > v1 --> v2
> > - handle platform_driver_register() failures
> > ---
> >  drivers/firmware/arm_scmi/Kconfig             |  6 +-
> >  drivers/firmware/arm_scmi/Makefile            |  2 +-
> >  drivers/firmware/arm_scmi/common.h            |  3 -
> >  drivers/firmware/arm_scmi/driver.c            |  3 -
> >  .../{optee.c => scmi_transport_optee.c}       | 91 ++++++++++---------
> >  5 files changed, 52 insertions(+), 53 deletions(-)  rename
> > drivers/firmware/arm_scmi/{optee.c => scmi_transport_optee.c} (90%)
> > 
> > diff --git a/drivers/firmware/arm_scmi/Kconfig
> > b/drivers/firmware/arm_scmi/Kconfig
> > index a4d44ef8bf45..def7e3f09356 100644
> > --- a/drivers/firmware/arm_scmi/Kconfig
> > +++ b/drivers/firmware/arm_scmi/Kconfig
> > @@ -89,8 +89,8 @@ config ARM_SCMI_TRANSPORT_MAILBOX
> >  	  will be called scmi_transport_mailbox.
> > 
> >  config ARM_SCMI_TRANSPORT_OPTEE
> > -	bool "SCMI transport based on OP-TEE service"
> > -	depends on OPTEE=y || OPTEE=ARM_SCMI_PROTOCOL
> > +	tristate "SCMI transport based on OP-TEE service"
> > +	depends on OPTEE
> >  	select ARM_SCMI_HAVE_TRANSPORT
> >  	select ARM_SCMI_HAVE_SHMEM
> >  	select ARM_SCMI_HAVE_MSG
> > @@ -100,6 +100,8 @@ config ARM_SCMI_TRANSPORT_OPTEE
> > 
> >  	  If you want the ARM SCMI PROTOCOL stack to include
> > support for a
> >  	  transport based on OP-TEE SCMI service, answer Y.
> > +	  This driver can also be built as a module.  If so, the module
> > +	  will be called scmi_transport_optee.
> > 
> >  config ARM_SCMI_TRANSPORT_SMC
> >  	tristate "SCMI transport based on SMC"
> > diff --git a/drivers/firmware/arm_scmi/Makefile
> > b/drivers/firmware/arm_scmi/Makefile
> > index 6868a47fa4ab..b04119ce972f 100644
> > --- a/drivers/firmware/arm_scmi/Makefile
> > +++ b/drivers/firmware/arm_scmi/Makefile
> > @@ -7,13 +7,13 @@ scmi-driver-
> > $(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT) += raw_mode.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
> >  scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
> > -scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
> > scmi-protocols-y := base.o clock.o perf.o power.o reset.o sensors.o
> > system.o voltage.o powercap.o  scmi-protocols-y += pinctrl.o  scmi-
> > module-objs := $(scmi-driver-y) $(scmi-protocols-y) $(scmi-transport-y)
> > 
> >  obj-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) +=
> > scmi_transport_smc.o
> >  obj-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) +=
> > scmi_transport_mailbox.o
> > +obj-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) +=
> > scmi_transport_optee.o
> > 
> >  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-core.o
> >  obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o diff --git
> > a/drivers/firmware/arm_scmi/common.h
> > b/drivers/firmware/arm_scmi/common.h
> > index edb786cde25c..0ce1d804b3fc 100644
> > --- a/drivers/firmware/arm_scmi/common.h
> > +++ b/drivers/firmware/arm_scmi/common.h
> > @@ -289,9 +289,6 @@ int
> > scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info
> > *cinfo,  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO  extern const
> > struct scmi_desc scmi_virtio_desc;  #endif -#ifdef
> > CONFIG_ARM_SCMI_TRANSPORT_OPTEE -extern const struct
> > scmi_desc scmi_optee_desc; -#endif
> > 
> >  void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr,
> > void *priv);
> > 
> > diff --git a/drivers/firmware/arm_scmi/driver.c
> > b/drivers/firmware/arm_scmi/driver.c
> > index b14c5326930a..67b416c7f2f5 100644
> > --- a/drivers/firmware/arm_scmi/driver.c
> > +++ b/drivers/firmware/arm_scmi/driver.c
> > @@ -3251,9 +3251,6 @@ ATTRIBUTE_GROUPS(versions);
> > 
> >  /* Each compatible listed below must have descriptor associated with
> > it */  static const struct of_device_id scmi_of_match[] = { -#ifdef
> > CONFIG_ARM_SCMI_TRANSPORT_OPTEE
> > -	{ .compatible = "linaro,scmi-optee", .data =
> > &scmi_optee_desc },
> > -#endif
> >  #ifdef CONFIG_ARM_SCMI_TRANSPORT_VIRTIO
> >  	{ .compatible = "arm,scmi-virtio", .data = &scmi_virtio_desc},
> > #endif diff --git a/drivers/firmware/arm_scmi/optee.c
> > b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> > similarity index 90%
> > rename from drivers/firmware/arm_scmi/optee.c rename to
> > drivers/firmware/arm_scmi/scmi_transport_optee.c
> > index 99f3b0bfb956..7a16c8d3e213 100644
> > --- a/drivers/firmware/arm_scmi/optee.c
> > +++ b/drivers/firmware/arm_scmi/scmi_transport_optee.c
> > @@ -1,6 +1,6 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  /*
> > - * Copyright (C) 2019-2021 Linaro Ltd.
> > + * Copyright (C) 2019-2024 Linaro Ltd.
> 
> This should be kept unchanged?
 
Yes, as said, it will be fixed in V3.

Thanks,
Cristian

Re: [PATCH 0/8] Make SCMI transport as standalone drivers

[Cristian Marussi]

On Tue, Jul 23, 2024 at 01:36:55PM +0000, Etienne CARRIERE wrote:
> Hi Cristian, Peng,
> 

Hi Etienne,

Thanks for giving this a go on your setup.

> On Thursday, July 11, 2024, Cristian Marussi worte:
> > On Thu, Jul 11, 2024 at 01:26:16PM +0000, Peng Fan wrote:
> > > > Subject: [PATCH 0/8] Make SCMI transport as standalone drivers
> > >
> > > You may need use V2 here :)
> > 
> > ...oh damn :P
> > 
> > > >
> > > > Hi all,
> > > >
> > > > Till now the SCMI transport layer was being built embedded into in the
> > > > core SCMI stack.
> > > >
> > > > Some of these transports, despite being currently part of the main
> > > > SCMI module, are indeed also registered with different subsystems like
> > > > optee or virtio, and actively probed also by those: this led to a few
> > > > awkward and convoluted tricks to properly handle such interactions at
> > > > boot time in the SCMI stack.
> > > >
> > > > Moreover some partner expressed the desire to be able to fully
> > > > modularize the transports components.
> > > >
> > > > This series aim to make all such transports as standalone drivers that
> > > > can be optionally loaded as modules.
> > > >
> > > > In order to do this, at first some new mechanism is introduced to
> > > > support this new capability while maintaining, in parallel, the old
> > > > legacy embedded transports; then each transport, one by one, is
> > > > transitioned to be a standalone driver and finally the old legacy
> > > > support for embedded transport is removed.
> > > >
> > > > Patch [1/8] is a mostly unrelated (but much needed) clean-up from
> > > > Peng, which I included in this series to avoid conflicts at merge.
> > > >
> > > > Patch [2/8] simply collects the existing datagram manipulation helpers
> > > > in a pair of function pointers structures, in preparation for later reworks.
> > > >
> > > > Patch [3/8] adds the bulk of the new logic to the core SCMI stack and
> > > > then each existing transport is transitioned to be a standalone driver in
> > > > patches 4,5,6,7 while shuffling around the compatibles. (no DT change
> > > > is needed of curse for backward compatibility) While doing this I kept
> > > > the module authorship in line with the main
> > > > author(S) as spitted out by git-blame.
> > > >
> > > > Finally patch [8/8] removes all the legacy dead code from the core
> > > > SCMI stack.
> > > >
> > > > No new symbol EXPORT has been added.
> > > >
> > > > The new transport drivers have been tested, as built-in and LKM, as
> > > > follows:
> > > >
> > > > - mailbox on JUNO
> > > > - virtio on emulation
> > > > - optee on QEMU/optee using Linaro setup
> > > >
> > > > Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> > > > testing commands, replies, delayed responses and notification.
> > > >
> > > > Multiple virtual SCMI instances support has been tested too.
> > > >
> > > > SMC has NOT been tested/exercised at run-time, only compile-tested.
> > > > (due to lack of hardware)
> > > >
> > > > Note that in this new setup, all the probe deferral and retries between
> > > > the SCMI core stack and the transports has been removed, since no
> > > > more needed.
> > > >
> > > > Moreover the new drivers have been tested also with a fully
> > > > modularized SCMI stack, i.e.:
> > > >
> > > >   scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor
> > > > modules ]
> > > >
> > > > ToBeDone:
> > > >  - completely remove any dependency at build time at the Kconfig level
> > > > between
> > > >    the SCMI core and the transport drivers: so that the transports will be
> > > >    dependent only on the related subsystems (optee/virtio/mailbox/smc)
> > > >    (easy to be done but maybe it is not worth...)
> > > >  - integrate per-platform transport configuration capabilities
> > > >    (max_rx_timeout_ms & friends..)
> > > >
> > > > Based on sudeep/for-next/scmi/updates.
> > > >
> > > > Any feedback, and especially testing (:D) is welcome.
> > > >
> > >
> > > For the v2 patchset:
> > > Tested-by: Peng Fan <peng.fan@nxp.com>  #i.MX95-19x19-EVK
> > >
> > 
> > Thanks a lot for the review and testing,
> > 
> > Cristian
> 
> 
> I've tested this v2 on stm32mp157c-scmi.dts. Using built-in modules
> works perfectly.  I've tweaked my platform setup to test the .ko and
> modprobe part. It works ok for the probe part but I faced kernel oops
> when unloading scmi-module after transport is loaded, used, then unoaded.
> The issue I saw is around calls to info->desc->ops->chan_free in
> scmi_cleanup_channels(). I wonder if there are some ops that were not
> unregistered when transport driver is unloaded.
> 

You are right, I could reproduce your oops in my QEMU/optee setup.

There was a bug in chan_free for optee that pre-dated this series....it
is exposed when unloading the scmi-module....I'll post a fix for this
as the initial patch of this series V3.

Moreover even once that was fixed, there was another bug in the
optee_remove of this new transport driver since I was calling the
platform_driver_unregister() too late (after the check for channel
empty)...as a result when you unload the scmi_transport_optee BEFORE the
scmi-module (which is another valid unload sequence option) the core
SCMI stack was NOT unbound like for the other transports.

Last but not least, I spotted another issue for all of these transport
drivers (and related WARN) when finally unloading the scmi-core module
(the last one to go) due to a missing device_release...this was easily
fixed just by using other platform drivers core helpers...so I
refactored more the DEFINE_SCMI_TRANSPORT_DRIVER macros internals...

Next week, on top of -rc1, I'll post a v3 with all the fixes I
mentioned.

Thanks,
Cristian

Re: [PATCH 0/8] Make SCMI transport as standalone drivers

[Cristian Marussi]

On Fri, Jul 12, 2024 at 02:02:32PM -0700, Florian Fainelli wrote:
> On 7/10/24 10:31, Cristian Marussi wrote:
> > Hi all,
> > 
> > Till now the SCMI transport layer was being built embedded into in the core
> > SCMI stack.
> > 
> > Some of these transports, despite being currently part of the main SCMI
> > module, are indeed also registered with different subsystems like optee or
> > virtio, and actively probed also by those: this led to a few awkward and
> > convoluted tricks to properly handle such interactions at boot time in the
> > SCMI stack.
> > 
> > Moreover some partner expressed the desire to be able to fully modularize
> > the transports components.
> > 
> > This series aim to make all such transports as standalone drivers that can
> > be optionally loaded as modules.
> > 
> > In order to do this, at first some new mechanism is introduced to support
> > this new capability while maintaining, in parallel, the old legacy embedded
> > transports; then each transport, one by one, is transitioned to be a
> > standalone driver and finally the old legacy support for embedded transport
> > is removed.
> > 
> > Patch [1/8] is a mostly unrelated (but much needed) clean-up from Peng,
> > which I included in this series to avoid conflicts at merge.
> > 
> > Patch [2/8] simply collects the existing datagram manipulation helpers in a
> > pair of function pointers structures, in preparation for later reworks.
> > 
> > Patch [3/8] adds the bulk of the new logic to the core SCMI stack and then
> > each existing transport is transitioned to be a standalone driver in
> > patches 4,5,6,7 while shuffling around the compatibles. (no DT change is
> > needed of curse for backward compatibility)
> > While doing this I kept the module authorship in line with the main
> > author(S) as spitted out by git-blame.
> > 
> > Finally patch [8/8] removes all the legacy dead code from the core SCMI
> > stack.
> > 
> > No new symbol EXPORT has been added.
> > 
> > The new transport drivers have been tested, as built-in and LKM, as
> > follows:
> > 
> > - mailbox on JUNO
> > - virtio on emulation
> > - optee on QEMU/optee using Linaro setup
> > 
> > Exercised using the regular SCMI drivers stack and the SCMI ACS suite,
> > testing commands, replies, delayed responses and notification.
> > 
> > Multiple virtual SCMI instances support has been tested too.
> > 
> > SMC has NOT been tested/exercised at run-time, only compile-tested.
> > (due to lack of hardware)
> > 
> > Note that in this new setup, all the probe deferral and retries between the
> > SCMI core stack and the transports has been removed, since no more needed.
> > 
> > Moreover the new drivers have been tested also with a fully modularized
> > SCMI stack, i.e.:
> > 
> >    scmi-core.ko + scmi-module.ko + scmi_transport_*.ko [ + vendor modules ]
> > 
> > ToBeDone:
> >   - completely remove any dependency at build time at the Kconfig level between
> >     the SCMI core and the transport drivers: so that the transports will be
> >     dependent only on the related subsystems (optee/virtio/mailbox/smc)
> >     (easy to be done but maybe it is not worth...)
> >   - integrate per-platform transport configuration capabilities
> >     (max_rx_timeout_ms & friends..)
> > 
> > Based on sudeep/for-next/scmi/updates.
> > 
> > Any feedback, and especially testing (:D) is welcome.
> 
> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>

Thanks for testing this, Florian.
Cristian

Re: [PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap

[Cristian Marussi]

On Sat, Jul 13, 2024 at 03:44:38AM +0800, kernel test robot wrote:
> Hi Cristian,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on soc/for-next]
> [also build test WARNING on next-20240712]
> [cannot apply to linus/master v6.10-rc7]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Cristian-Marussi/firmware-arm_scmi-Introduce-setup_shmem_iomap/20240711-062033
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
> patch link:    https://lore.kernel.org/r/20240710173153.4060457-2-cristian.marussi%40arm.com
> patch subject: [PATCH v2 1/8] firmware: arm_scmi: Introduce setup_shmem_iomap
> config: arm64-randconfig-r132-20240712 (https://download.01.org/0day-ci/archive/20240713/202407130355.IWguWKJm-lkp@intel.com/config)
> compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
> reproduce: (https://download.01.org/0day-ci/archive/20240713/202407130355.IWguWKJm-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202407130355.IWguWKJm-lkp@intel.com/
> 
> sparse warnings: (new ones prefixed by >>)
> >> drivers/firmware/arm_scmi/shmem.c:153:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
>    drivers/firmware/arm_scmi/shmem.c:153:31: sparse:     expected void [noderef] __iomem *
>    drivers/firmware/arm_scmi/shmem.c:153:31: sparse:     got void *
>    drivers/firmware/arm_scmi/shmem.c:156:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
>    drivers/firmware/arm_scmi/shmem.c:156:31: sparse:     expected void [noderef] __iomem *
>    drivers/firmware/arm_scmi/shmem.c:156:31: sparse:     got void *
>    drivers/firmware/arm_scmi/shmem.c:165:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
>    drivers/firmware/arm_scmi/shmem.c:165:31: sparse:     expected void [noderef] __iomem *
>    drivers/firmware/arm_scmi/shmem.c:165:31: sparse:     got void *
>    drivers/firmware/arm_scmi/shmem.c:172:31: sparse: sparse: incorrect type in return expression (different address spaces) @@     expected void [noderef] __iomem * @@     got void * @@
>    drivers/firmware/arm_scmi/shmem.c:172:31: sparse:     expected void [noderef] __iomem *
>    drivers/firmware/arm_scmi/shmem.c:172:31: sparse:     got void *
> 
> vim +153 drivers/firmware/arm_scmi/shmem.c
> 
>    138	
>    139	void __iomem *setup_shmem_iomap(struct scmi_chan_info *cinfo,
>    140					struct device *dev, bool tx,
>    141					struct resource *res)
>    142	{
>    143		struct device_node *shmem __free(device_node);
>    144		const char *desc = tx ? "Tx" : "Rx";
>    145		int ret, idx = tx ? 0 : 1;
>    146		struct device *cdev = cinfo->dev;
>    147		struct resource lres = {};
>    148		resource_size_t size;
>    149		void __iomem *addr;
>    150	
>    151		shmem = of_parse_phandle(cdev->of_node, "shmem", idx);
>    152		if (!shmem)
>  > 153			return ERR_PTR(-ENODEV);
> 

Will be fixed in V3 using IOMEM_ERR_PTR()

Thanks,
Cristian