FAILED: patch "[PATCH] firmware: arm_scmi: Ensure that the message-id supports" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] firmware: arm_scmi: Ensure that the message-id supports" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 94a263f981a3fa3d93f65c31e0fed0756736be43
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025062018-joyfully-unmixable-8b37@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 94a263f981a3fa3d93f65c31e0fed0756736be43 Mon Sep 17 00:00:00 2001
From: Sibi Sankar <quic_sibis@quicinc.com>
Date: Tue, 29 Apr 2025 15:11:06 +0100
Subject: [PATCH] firmware: arm_scmi: Ensure that the message-id supports
 fastchannel

Currently the perf and powercap protocol relies on the protocol domain
attributes, which just ensures that one fastchannel per domain, before
instantiating fastchannels for all possible message-ids. Fix this by
ensuring that each message-id supports fastchannel before initialization.

Logs:
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:0] - ret:-95. Using regular messaging
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:1] - ret:-95. Using regular messaging
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:2] - ret:-95. Using regular messaging

CC: stable@vger.kernel.org
Reported-by: Johan Hovold <johan+linaro@kernel.org>
Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/
Fixes: 6f9ea4dabd2d ("firmware: arm_scmi: Generalize the fast channel support")
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
[Cristian: Modified the condition checked to establish support or not]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Message-Id: <20250429141108.406045-2-cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 520aa5846916..cf2bc8b8d881 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1729,6 +1729,39 @@ static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
 	return info->desc->max_msg_size;
 }
 
+/**
+ * scmi_protocol_msg_check  - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ *		attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+				   u32 message_id, u32 *attributes)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+			    sizeof(__le32), 0, &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(message_id, t->tx.buf);
+	ret = do_xfer(ph, t);
+	if (!ret && attributes)
+		*attributes = get_unaligned_le32(t->rx.buf);
+	xfer_put(ph, t);
+
+	return ret;
+}
+
 /**
  * struct scmi_iterator  - Iterator descriptor
  * @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1870,6 +1903,7 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
 	int ret;
 	u32 flags;
 	u64 phys_addr;
+	u32 attributes;
 	u8 size;
 	void __iomem *addr;
 	struct scmi_xfer *t;
@@ -1878,6 +1912,15 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
 	struct scmi_msg_resp_desc_fc *resp;
 	const struct scmi_protocol_instance *pi = ph_to_pi(ph);
 
+	/* Check if the MSG_ID supports fastchannel */
+	ret = scmi_protocol_msg_check(ph, message_id, &attributes);
+	if (ret || !MSG_SUPPORTS_FASTCHANNEL(attributes)) {
+		dev_dbg(ph->dev,
+			"Skip FC init for 0x%02X/%d  domain:%d - ret:%d\n",
+			pi->proto->id, message_id, domain, ret);
+		return;
+	}
+
 	if (!p_addr) {
 		ret = -EINVAL;
 		goto err_out;
@@ -1995,39 +2038,6 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
 		SCMI_PROTO_FC_RING_DB(64);
 }
 
-/**
- * scmi_protocol_msg_check  - Check protocol message attributes
- *
- * @ph: A reference to the protocol handle.
- * @message_id: The ID of the message to check.
- * @attributes: A parameter to optionally return the retrieved message
- *		attributes, in case of Success.
- *
- * An helper to check protocol message attributes for a specific protocol
- * and message pair.
- *
- * Return: 0 on SUCCESS
- */
-static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
-				   u32 message_id, u32 *attributes)
-{
-	int ret;
-	struct scmi_xfer *t;
-
-	ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
-			    sizeof(__le32), 0, &t);
-	if (ret)
-		return ret;
-
-	put_unaligned_le32(message_id, t->tx.buf);
-	ret = do_xfer(ph, t);
-	if (!ret && attributes)
-		*attributes = get_unaligned_le32(t->rx.buf);
-	xfer_put(ph, t);
-
-	return ret;
-}
-
 static const struct scmi_proto_helpers_ops helpers_ops = {
 	.extended_name_get = scmi_common_extended_name_get,
 	.get_max_msg_size = scmi_common_get_max_msg_size,
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index aaee57cdcd55..d62c4469d1fd 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -31,6 +31,8 @@
 
 #define SCMI_PROTOCOL_VENDOR_BASE	0x80
 
+#define MSG_SUPPORTS_FASTCHANNEL(x)	((x) & BIT(0))
+
 enum scmi_common_cmd {
 	PROTOCOL_VERSION = 0x0,
 	PROTOCOL_ATTRIBUTES = 0x1,

[PATCH 6.1.y 1/2] firmware: arm_scmi: Add a common helper to check if a message is supported

[Sudeep Holla]

From: Cristian Marussi <cristian.marussi@arm.com>

[ Upstream commit 637b6d6cae9c42db5a9525da67c991294924d2cd ]

A common helper is provided to check if a specific protocol message is
supported or not.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20240212123233.1230090-3-cristian.marussi@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/firmware/arm_scmi/driver.c    | 34 +++++++++++++++++++++++++++
 drivers/firmware/arm_scmi/protocols.h |  4 ++++
 2 files changed, 38 insertions(+)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index fe06dc193689..aa89bbf04eb2 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1450,10 +1450,44 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
 #endif
 }
 
+/**
+ * scmi_protocol_msg_check  - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ *		attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+				   u32 message_id, u32 *attributes)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+			    sizeof(__le32), 0, &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(message_id, t->tx.buf);
+	ret = do_xfer(ph, t);
+	if (!ret && attributes)
+		*attributes = get_unaligned_le32(t->rx.buf);
+	xfer_put(ph, t);
+
+	return ret;
+}
+
 static const struct scmi_proto_helpers_ops helpers_ops = {
 	.extended_name_get = scmi_common_extended_name_get,
 	.iter_response_init = scmi_iterator_init,
 	.iter_response_run = scmi_iterator_run,
+	.protocol_msg_check = scmi_protocol_msg_check,
 	.fastchannel_init = scmi_common_fastchannel_init,
 	.fastchannel_db_ring = scmi_common_fastchannel_db_ring,
 };
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index 2f3bf691db7c..9024281f172a 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -243,6 +243,8 @@ struct scmi_fc_info {
  *			provided in @ops.
  * @iter_response_run: A common helper to trigger the run of a previously
  *		       initialized iterator.
+ * @protocol_msg_check: A common helper to check is a specific protocol message
+ *			is supported.
  * @fastchannel_init: A common helper used to initialize FC descriptors by
  *		      gathering FC descriptions from the SCMI platform server.
  * @fastchannel_db_ring: A common helper to ring a FC doorbell.
@@ -255,6 +257,8 @@ struct scmi_proto_helpers_ops {
 				    unsigned int max_resources, u8 msg_id,
 				    size_t tx_size, void *priv);
 	int (*iter_response_run)(void *iter);
+	int (*protocol_msg_check)(const struct scmi_protocol_handle *ph,
+				  u32 message_id, u32 *attributes);
 	void (*fastchannel_init)(const struct scmi_protocol_handle *ph,
 				 u8 describe_id, u32 message_id,
 				 u32 valid_size, u32 domain,
-- 
2.34.1

[PATCH 6.1.y 2/2] firmware: arm_scmi: Ensure that the message-id supports fastchannel

[Sudeep Holla]

From: Sibi Sankar <quic_sibis@quicinc.com>

[ Upstream commit 94a263f981a3fa3d93f65c31e0fed0756736be43 ]

Currently the perf and powercap protocol relies on the protocol domain
attributes, which just ensures that one fastchannel per domain, before
instantiating fastchannels for all possible message-ids. Fix this by
ensuring that each message-id supports fastchannel before initialization.

Logs:
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:0] - ret:-95. Using regular messaging
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:1] - ret:-95. Using regular messaging
  |  scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:2] - ret:-95. Using regular messaging

CC: stable@vger.kernel.org # 6.1.x : 637b6d6cae9c : firmware: arm_scmi: Add a common helper to check if a message is supported
Reported-by: Johan Hovold <johan+linaro@kernel.org>
Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/
Fixes: 6f9ea4dabd2d ("firmware: arm_scmi: Generalize the fast channel support")
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
[Cristian: Modified the condition checked to establish support or not]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Message-Id: <20250429141108.406045-2-cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/firmware/arm_scmi/driver.c    | 76 +++++++++++++++------------
 drivers/firmware/arm_scmi/protocols.h |  2 +
 2 files changed, 45 insertions(+), 33 deletions(-)

Hi Greg,

Sorry for the delay, was hoping the author would pick this up as it was
issue on their platform. I assume they don't have interest in stable tree
backport though they do run android stable kernels.

Anyways, there is a dependency patch which I have added just to keep it
close to mainline.

Alternative or easier way is to squash them into one and add the function
in this backport to avoid adding the dependent patch separately.

Also, even with dependency picked up, it needs backport as the patch won't
apply easily. So I am sending both though dependent patch applies cleanly
without any issues.

Regards,
Sudeep


diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index aa89bbf04eb2..53fd9b17b9bd 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1177,6 +1177,39 @@ static int scmi_common_extended_name_get(const struct scmi_protocol_handle *ph,
 	return ret;
 }
 
+/**
+ * scmi_protocol_msg_check  - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ *		attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+				   u32 message_id, u32 *attributes)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+			    sizeof(__le32), 0, &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(message_id, t->tx.buf);
+	ret = do_xfer(ph, t);
+	if (!ret && attributes)
+		*attributes = get_unaligned_le32(t->rx.buf);
+	xfer_put(ph, t);
+
+	return ret;
+}
+
 /**
  * struct scmi_iterator  - Iterator descriptor
  * @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1318,6 +1351,7 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
 	int ret;
 	u32 flags;
 	u64 phys_addr;
+	u32 attributes;
 	u8 size;
 	void __iomem *addr;
 	struct scmi_xfer *t;
@@ -1326,6 +1360,15 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
 	struct scmi_msg_resp_desc_fc *resp;
 	const struct scmi_protocol_instance *pi = ph_to_pi(ph);
 
+	/* Check if the MSG_ID supports fastchannel */
+	ret = scmi_protocol_msg_check(ph, message_id, &attributes);
+	if (ret || !MSG_SUPPORTS_FASTCHANNEL(attributes)) {
+		dev_dbg(ph->dev,
+			"Skip FC init for 0x%02X/%d  domain:%d - ret:%d\n",
+			pi->proto->id, message_id, domain, ret);
+		return;
+	}
+
 	if (!p_addr) {
 		ret = -EINVAL;
 		goto err_out;
@@ -1450,39 +1493,6 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
 #endif
 }
 
-/**
- * scmi_protocol_msg_check  - Check protocol message attributes
- *
- * @ph: A reference to the protocol handle.
- * @message_id: The ID of the message to check.
- * @attributes: A parameter to optionally return the retrieved message
- *		attributes, in case of Success.
- *
- * An helper to check protocol message attributes for a specific protocol
- * and message pair.
- *
- * Return: 0 on SUCCESS
- */
-static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
-				   u32 message_id, u32 *attributes)
-{
-	int ret;
-	struct scmi_xfer *t;
-
-	ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
-			    sizeof(__le32), 0, &t);
-	if (ret)
-		return ret;
-
-	put_unaligned_le32(message_id, t->tx.buf);
-	ret = do_xfer(ph, t);
-	if (!ret && attributes)
-		*attributes = get_unaligned_le32(t->rx.buf);
-	xfer_put(ph, t);
-
-	return ret;
-}
-
 static const struct scmi_proto_helpers_ops helpers_ops = {
 	.extended_name_get = scmi_common_extended_name_get,
 	.iter_response_init = scmi_iterator_init,
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index 9024281f172a..1a9753608a2b 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -29,6 +29,8 @@
 #define PROTOCOL_REV_MAJOR(x)	((u16)(FIELD_GET(PROTOCOL_REV_MAJOR_MASK, (x))))
 #define PROTOCOL_REV_MINOR(x)	((u16)(FIELD_GET(PROTOCOL_REV_MINOR_MASK, (x))))
 
+#define MSG_SUPPORTS_FASTCHANNEL(x)	((x) & BIT(0))
+
 enum scmi_common_cmd {
 	PROTOCOL_VERSION = 0x0,
 	PROTOCOL_ATTRIBUTES = 0x1,
-- 
2.34.1