[PATCH v14 00/15] PCI: EP: Add RC-to-EP doorbell with platform MSI controller

[PATCH v14 00/15] PCI: EP: Add RC-to-EP doorbell with platform MSI controller

[Frank Li]

┌────────────┐   ┌───────────────────────────────────┐   ┌────────────────┐
│            │   │                                   │   │                │
│            │   │ PCI Endpoint                      │   │ PCI Host       │
│            │   │                                   │   │                │
│            │◄──┤ 1.platform_msi_domain_alloc_irqs()│   │                │
│            │   │                                   │   │                │
│ MSI        ├──►│ 2.write_msi_msg()                 ├──►├─BAR<n>         │
│ Controller │   │   update doorbell register address│   │                │
│            │   │   for BAR                         │   │                │
│            │   │                                   │   │ 3. Write BAR<n>│
│            │◄──┼───────────────────────────────────┼───┤                │
│            │   │                                   │   │                │
│            ├──►│ 4.Irq Handle                      │   │                │
│            │   │                                   │   │                │
│            │   │                                   │   │                │
└────────────┘   └───────────────────────────────────┘   └────────────────┘

This patches based on old https://lore.kernel.org/imx/20221124055036.1630573-1-Frank.Li@nxp.com/

Original patch only target to vntb driver. But actually it is common
method.

This patches add new API to pci-epf-core, so any EP driver can use it.

Previous v2 discussion here.
https://lore.kernel.org/imx/20230911220920.1817033-1-Frank.Li@nxp.com/

Changes in v14:
Marc Zyngier raised concerns about adding DOMAIN_BUS_DEVICE_PCI_EP_MSI. As
a result, the approach has been reverted to the v9 method. However, there
are several improvements:

MSI now supports msi-map in addition to msi-parent.
  - The struct device: id is used as the endpoint function (EPF) device
identity to map to the stream ID (sideband information).
  - The EPC device tree source (DTS) utilizes msi-map to provide such
information.
  - The EPF device's of_node is set to the EPC controller’s node. This
approach is commonly used for multi-function device (MFD) platform child
devices, allowing them to inherit properties from the MFD device’s DTS,
such as reset-cells and gpio-cells. This method is well-suited for the
current case, as the EPF is inherently created/binded to the EPC and
should inherit the EPC’s DTS node properties.

Additionally:

Since the basic IMX95 LUT support has already been merged into the
mainline, a DTS and driver increment patch is added to complete the
solution. The patch is rebased onto the latest linux-next tree and
aligned with the new pcitest framework.

- Link to v13: https://lore.kernel.org/r/20241218-ep-msi-v13-0-646e2192dc24@nxp.com

Changes in v13:
- Change to use DOMAIN_BUS_PCI_DEVICE_EP_MSI
- Change request id as  func | vfunc << 3
- Remove IRQ_DOMAIN_MSI_IMMUTABLE

Thomas Gleixner:

I hope capture all your points in review comments. If missed, let me know.

- Link to v12: https://lore.kernel.org/r/20241211-ep-msi-v12-0-33d4532fa520@nxp.com

Changes in v12:
- Change to use IRQ_DOMAIN_MSI_IMMUTABLE and add help function
irq_domain_msi_is_immuatble().
- split PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check to 3 patches
- Link to v11: https://lore.kernel.org/r/20241209-ep-msi-v11-0-7434fa8397bd@nxp.com

Changes in v11:
- Change to use MSI_FLAG_MSG_IMMUTABLE
- Link to v10: https://lore.kernel.org/r/20241204-ep-msi-v10-0-87c378dbcd6d@nxp.com

Changes in v10:

Thomas Gleixner:
	There are big change in pci-ep-msi.c. I am sure if go on the
corrent path. The key improvement is remove only 1 function devices's
limitation.

	I use new patch for imutable check, which relative additional
feature compared to base enablement patch.

- Remove patch Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
- Add new patch irqchip/gic-v3-its: Avoid overwriting msi_prepare callback if provided by msi_domain_info
- Remove only support 1 endpoint function limiation.
- Create one MSI domain for each endpoint function devices.
- Use "msi-map" in pci ep controler node, instead of of msi-parent. first
argument is
	(func_no << 8 | vfunc_no)

- Link to v9: https://lore.kernel.org/r/20241203-ep-msi-v9-0-a60dbc3f15dd@nxp.com

Changes in v9
- Add patch platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
- Remove patch PCI: endpoint: Add pci_epc_get_fn() API for customizable filtering
- Remove API pci_epf_align_inbound_addr_lo_hi
- Move doorbell_alloc in to doorbell_enable function.
- Link to v8: https://lore.kernel.org/r/20241116-ep-msi-v8-0-6f1f68ffd1bb@nxp.com

Changes in v8:
- update helper function name to pci_epf_align_inbound_addr()
- Link to v7: https://lore.kernel.org/r/20241114-ep-msi-v7-0-d4ac7aafbd2c@nxp.com

Changes in v7:
- Add helper function pci_epf_align_addr();
- Link to v6: https://lore.kernel.org/r/20241112-ep-msi-v6-0-45f9722e3c2a@nxp.com

Changes in v6:
- change doorbell_addr to doorbell_offset
- use round_down()
- add Niklas's test by tag
- rebase to pci/endpoint
- Link to v5: https://lore.kernel.org/r/20241108-ep-msi-v5-0-a14951c0d007@nxp.com

Changes in v5:
- Move request_irq to epf test function driver for more flexiable user case
- Add fixed size bar handler
- Some minor improvememtn to see each patches's changelog.
- Link to v4: https://lore.kernel.org/r/20241031-ep-msi-v4-0-717da2d99b28@nxp.com

Changes in v4:
- Remove patch genirq/msi: Add cleanup guard define for msi_lock_descs()/msi_unlock_descs()
- Use new method to avoid compatible problem.
  Add new command DOORBELL_ENABLE and DOORBELL_DISABLE.
  pcitest -B send DOORBELL_ENABLE first, EP test function driver try to
remap one of BAR_N (except test register bar) to ITS MSI MMIO space. Old
driver don't support new command, so failure return, not side effect.
  After test, DOORBELL_DISABLE command send out to recover original map, so
pcitest bar test can pass as normal.
- Other detail change see each patches's change log
- Link to v3: https://lore.kernel.org/r/20241015-ep-msi-v3-0-cedc89a16c1a@nxp.com

Change from v2 to v3
- Fixed manivannan's comments
- Move common part to pci-ep-msi.c and pci-ep-msi.h
- rebase to 6.12-rc1
- use RevID to distingiush old version

mkdir /sys/kernel/config/pci_ep/functions/pci_epf_test/func1
echo 16 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/msi_interrupts
echo 0x080c > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/deviceid
echo 0x1957 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/vendorid
echo 1 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/revid
^^^^^^ to enable platform msi support.
ln -s /sys/kernel/config/pci_ep/functions/pci_epf_test/func1 /sys/kernel/config/pci_ep/controllers/4c380000.pcie-ep

- use new device ID, which identify support doorbell to avoid broken
compatility.

    Enable doorbell support only for PCI_DEVICE_ID_IMX8_DB, while other devices
    keep the same behavior as before.

           EP side             RC with old driver      RC with new driver
    PCI_DEVICE_ID_IMX8_DB          no probe              doorbell enabled
    Other device ID             doorbell disabled*       doorbell disabled*

    * Behavior remains unchanged.

Change from v1 to v2
- Add missed patch for endpont/pci-epf-test.c
- Move alloc and free to epc driver from epf.
- Provide general help function for EPC driver to alloc platform msi irq.
- Fixed manivannan's comments.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Frank Li (15):
      platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
      irqdomain: Add IRQ_DOMAIN_FLAG_MSI_IMMUTABLE and irq_domain_is_msi_immutable()
      irqchip/gic-v3-its: Set IRQ_DOMAIN_FLAG_MSI_IMMUTABLE for ITS
      irqchip/gic-v3-its: Add support for device tree msi-map and msi-mask
      PCI: endpoint: Set ID and of_node for function driver
      PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller
      PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check
      PCI: endpoint: Add pci_epf_align_inbound_addr() helper for address alignment
      PCI: endpoint: pci-epf-test: Add doorbell test support
      misc: pci_endpoint_test: Add doorbell test case
      selftests: pci_endpoint: Add doorbell test case
      pci: imx6: Add helper function imx_pcie_add_lut_by_rid()
      pci: imx6: Add LUT setting for MSI/IOMMU in Endpoint mode
      arm64: dts: imx95: Add msi-map for pci-ep device
      arm64: dts: imx95-19x19-evk: Add PCIe1 endpoint function overlay file

 arch/arm64/boot/dts/freescale/Makefile             |   3 +
 .../dts/freescale/imx95-19x19-evk-pcie1-ep.dtso    |  21 ++++
 arch/arm64/boot/dts/freescale/imx95.dtsi           |   1 +
 drivers/base/platform-msi.c                        |   1 +
 drivers/irqchip/irq-gic-v3-its-msi-parent.c        |   8 ++
 drivers/irqchip/irq-gic-v3-its.c                   |   2 +-
 drivers/misc/pci_endpoint_test.c                   |  81 +++++++++++++
 drivers/pci/controller/dwc/pci-imx6.c              |  25 ++--
 drivers/pci/endpoint/Makefile                      |   2 +-
 drivers/pci/endpoint/functions/pci-epf-test.c      | 132 +++++++++++++++++++++
 drivers/pci/endpoint/pci-ep-msi.c                  |  89 ++++++++++++++
 drivers/pci/endpoint/pci-epf-core.c                |  48 ++++++++
 include/linux/irqdomain.h                          |   7 ++
 include/linux/pci-ep-msi.h                         |  26 ++++
 include/linux/pci-epf.h                            |  21 ++++
 include/uapi/linux/pcitest.h                       |   1 +
 .../selftests/pci_endpoint/pci_endpoint_test.c     |  25 ++++
 17 files changed, 483 insertions(+), 10 deletions(-)
---
base-commit: 00f3246adeeacbda0bd0b303604e46eb59c32e6e
change-id: 20241010-ep-msi-8b4cab33b1be

Best regards,
---
Frank Li <Frank.Li@nxp.com>

[PATCH v14 01/15] platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()

[Frank Li]

The follow steps trigger kernel dump warning and
platform_device_msi_init_and_alloc_irqs() return false.

1: platform_device_msi_init_and_alloc_irqs();
2: platform_device_msi_free_irqs_all();
3: platform_device_msi_init_and_alloc_irqs();

[   76.713677] WARNING: CPU: 3 PID: 134 at kernel/irq/msi.c:1028 msi_create_device_irq_domain+0x1bc/0x22c
[   76.723010] Modules linked in:
[   76.726082] CPU: 3 UID: 0 PID: 134 Comm: kworker/3:1H Not tainted 6.13.0-rc1-00015-gd60b98003b43-dirty #57
[   76.735741] Hardware name: NXP i.MX95 19X19 board (DT)
[   76.740883] Workqueue: kpcitest pci_epf_test_cmd_handler
[   76.746212] pstate: a0400009 (NzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   76.753172] pc : msi_create_device_irq_domain+0x1bc/0x22c
[   76.758586] lr : msi_create_device_irq_domain+0x104/0x22c
[   76.763988] sp : ffff800083f43be0
[   76.767313] x29: ffff800083f43be0 x28: 0000000000000000 x27: ffff8000827a7000
[   76.774466] x26: ffff00008085f400 x25: ffff00008000b180 x24: ffff000080fc6410
[   76.781624] x23: ffff000085704cc0 x22: ffff8000811c8828 x21: ffff000085704cc0
[   76.788774] x20: ffff000082814000 x19: 0000000000000000 x18: ffffffffffffffff
[   76.795933] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[   76.803083] x14: 0000000000000000 x13: 0000000f00000000 x12: 0000000000000000
[   76.810233] x11: 0000000000000000 x10: 000000000000002d x9 : ffff800083f43ba0
[   76.817383] x8 : 00000000ffffffff x7 : 0000000000000019 x6 : ffff0000857e443a
[   76.824533] x5 : 0000000000000000 x4 : ffffffffffffffff x3 : ffff000085704ce8
[   76.831683] x2 : ffff000080835640 x1 : 0000000000000213 x0 : ffff0000877189c0
[   76.838840] Call trace:
[   76.841287]  msi_create_device_irq_domain+0x1bc/0x22c (P)
[   76.846701]  msi_create_device_irq_domain+0x104/0x22c (L)
[   76.852118]  platform_device_msi_init_and_alloc_irqs+0x6c/0xb8

Do below two things in platform_device_msi_init_and_alloc_irqs().
- msi_create_device_irq_domain()
- msi_domain_alloc_irqs_range()

But only call msi_domain_free_irqs_all() in
platform_device_msi_free_irqs_all(), which missed call
msi_remove_device_irq_domain(). This cause above kernel dump when call
platform_device_msi_init_and_alloc_irqs() again.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- bring back from v9 and remove fixup and cc stable before it is new use
case.
---
 drivers/base/platform-msi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
index 0e60dd650b5e0..70db08f3ac6fa 100644
--- a/drivers/base/platform-msi.c
+++ b/drivers/base/platform-msi.c
@@ -95,5 +95,6 @@ EXPORT_SYMBOL_GPL(platform_device_msi_init_and_alloc_irqs);
 void platform_device_msi_free_irqs_all(struct device *dev)
 {
 	msi_domain_free_irqs_all(dev, MSI_DEFAULT_DOMAIN);
+	msi_remove_device_irq_domain(dev, MSI_DEFAULT_DOMAIN);
 }
 EXPORT_SYMBOL_GPL(platform_device_msi_free_irqs_all);

-- 
2.34.1

[PATCH v14 02/15] irqdomain: Add IRQ_DOMAIN_FLAG_MSI_IMMUTABLE and irq_domain_is_msi_immutable()

[Frank Li]

Add the flag IRQ_DOMAIN_FLAG_MSI_IMMUTABLE and the API function
irq_domain_is_msi_immutable() to check if the MSI controller retains an
immutable address/data pair during irq_set_affinity().

Ensure compatibility with MSI users like PCIe Endpoint Doorbell, which
require the address/data pair to remain unchanged after setup. Use this
function to verify if the MSI controller is immutable.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- Roll back to v12 version because Marc Zyngier have concern about add
DOMAIN_BUS_DEVICE_PCI_EP_MSI.
https://lore.kernel.org/imx/861pxfq315.wl-maz@kernel.org/

Change from v11 to v12
- change to IRQ_DOMAIN_FLAG_MSI_IMMUTABLE to minimized the code change.
---
 include/linux/irqdomain.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index e432b6a12a32f..3dbe05d8740e6 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -231,6 +231,9 @@ enum {
 	/* Irq domain must destroy generic chips when removed */
 	IRQ_DOMAIN_FLAG_DESTROY_GC	= (1 << 10),
 
+	/* Address and data pair is mutable when irq_set_affinity() */
+	IRQ_DOMAIN_FLAG_MSI_IMMUTABLE	= (1 << 11),
+
 	/*
 	 * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
 	 * for implementation specific purposes and ignored by the
@@ -692,6 +695,10 @@ static inline bool irq_domain_is_msi_device(struct irq_domain *domain)
 	return domain->flags & IRQ_DOMAIN_FLAG_MSI_DEVICE;
 }
 
+static inline bool irq_domain_is_msi_immutable(struct irq_domain *domain)
+{
+	return domain->flags & IRQ_DOMAIN_FLAG_MSI_IMMUTABLE;
+}
 #else	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
 			unsigned int nr_irqs, int node, void *arg)

-- 
2.34.1

[PATCH v14 03/15] irqchip/gic-v3-its: Set IRQ_DOMAIN_FLAG_MSI_IMMUTABLE for ITS

[Frank Li]

Set the IRQ_DOMAIN_FLAG_MSI_IMMUTABLE flag for ITS, as it does not change
the address/data pair after setup.

Ensure compatibility with MSI users, such as PCIe Endpoint Doorbell, which
require the address/data pair to remain unchanged. Enable PCIe endpoints to
use ITS for triggering doorbells from the PCIe Root Complex (RC) side.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v12
- roll back to v12 version because Marc Zyngier have concern about add
DOMAIN_BUS_DEVICE_PCI_EP_MSI.
https://lore.kernel.org/imx/861pxfq315.wl-maz@kernel.org/

change from v11 to v12
- new patch
---
 drivers/irqchip/irq-gic-v3-its.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 8c3ec5734f1ef..7c0a97a1bf8be 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -5126,7 +5126,7 @@ static int its_init_domain(struct its_node *its)
 	irq_domain_update_bus_token(inner_domain, DOMAIN_BUS_NEXUS);
 
 	inner_domain->msi_parent_ops = &gic_v3_its_msi_parent_ops;
-	inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
+	inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT | IRQ_DOMAIN_FLAG_MSI_IMMUTABLE;
 
 	return 0;
 }

-- 
2.34.1

[PATCH v14 04/15] irqchip/gic-v3-its: Add support for device tree msi-map and msi-mask

[Frank Li]

Some platform devices create child devices dynamically and require the
parent device's msi-map to map device IDs to actual sideband information.

A typical use case is using ITS as a PCIe Endpoint Controller(EPC)'s
doorbell function, where PCI hosts send TLP memory writes to the EP
controller. The EP controller converts these writes to AXI transactions
and appends platform-specific sideband information.  See below figure.

               ┌────────────────────────────────┐
               │                                │
               │     PCI Endpoint Controller    │
               │                                │
               │  ┌─────┐   ┌─────┐     ┌─────┐ │
    PCI Bus    │  │     │   │     │     │     │ │
    ─────────► │  │Func1│   │Func2│ ... │Func │ │
    TLP Memory │  │     │   │     │     │<n>  │ │
    Write Push │  │     │   │     │     │     │ │
    DoorBell   │  └─┬─┬─┘   └──┬──┘     └──┬──┘ │
               │    │ │        │           │    │
               └────┼─┼────────┼───────────┼────┘
        sideband    │ │ Address│           │
        information ▼ ▼ /Data  ▼           ▼
                   ┌────────────────────────┐
                   │    MSI Controller      │
                   └────────────────────────┘

EPC's DTS will provide such information by msi-map and msi-mask. A
simplified dts as

pcie-ep@10000000 {
	...
	msi-map = <0 &its 0xc 8>;
                          ^^^ 0xc is implement defined sideband information,
			      which append to AXI write transaction.
	           ^ 0 is function index.

	msi-mask = <0x7>
}

Check msi-map if msi-parent missed to keep compatility with existed system.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/irqchip/irq-gic-v3-its-msi-parent.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its-msi-parent.c b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
index e150365fbe892..6c7389bb84a4a 100644
--- a/drivers/irqchip/irq-gic-v3-its-msi-parent.c
+++ b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
@@ -118,6 +118,14 @@ static int of_pmsi_get_dev_id(struct irq_domain *domain, struct device *dev,
 		index++;
 	} while (!ret);
 
+	if (ret) {
+		struct device_node *np = NULL;
+
+		ret = of_map_id(dev->of_node, dev->id, "msi-map", "msi-map-mask", &np, dev_id);
+		if (np)
+			of_node_put(np);
+	}
+
 	return ret;
 }
 

-- 
2.34.1

[PATCH v14 05/15] PCI: endpoint: Set ID and of_node for function driver

[Frank Li]

Set device ID as 'vfunc_no << 3 | func_no' and use
'device_set_of_node_from_dev()' to set 'of_node' the same as the EPC parent
device.

Currently, EPF 'of_node' is NULL, but many functions depend on 'of_node'
settings, such as DMA, IOMMU, and MSI. At present, all DMA allocation
functions use the EPC's device node, but they should use the EPF one.
For multiple function drivers, IOMMU/MSI should be different for each
function driver.

If multiple function devices share the same EPC device, there will be
no isolation between them. Setting the ID and 'of_node' prepares for
proper support.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/pci/endpoint/pci-epf-core.c | 4 ++++
 include/linux/pci-epf.h             | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index 50bc2892a36c5..f728ee2660a4e 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -120,12 +120,16 @@ int pci_epf_bind(struct pci_epf *epf)
 		epf_vf->sec_epc_func_no = epf->sec_epc_func_no;
 		epf_vf->epc = epf->epc;
 		epf_vf->sec_epc = epf->sec_epc;
+		epf_vf->dev.id = PCI_EPF_DEVID(epf->func_no, vfunc_no);
+		device_set_of_node_from_dev(&epf_vf->dev, epc->dev.parent);
 		ret = epf_vf->driver->ops->bind(epf_vf);
 		if (ret)
 			goto ret;
 		epf_vf->is_bound = true;
 	}
 
+	epf->dev.id = PCI_EPF_DEVID(epf->func_no, 0);
+	device_set_of_node_from_dev(&epf->dev, epc->dev.parent);
 	ret = epf->driver->ops->bind(epf);
 	if (ret)
 		goto ret;
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index ee6156bcbbd05..d2790b8b29394 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -212,6 +212,8 @@ static inline void *epf_get_drvdata(struct pci_epf *epf)
 	return dev_get_drvdata(&epf->dev);
 }
 
+#define PCI_EPF_DEVID(func_no, vfunc_no) ((vfunc_no) << 3 | (func_no))
+
 struct pci_epf *pci_epf_create(const char *name);
 void pci_epf_destroy(struct pci_epf *epf);
 int __pci_epf_register_driver(struct pci_epf_driver *driver,

-- 
2.34.1

[PATCH v14 06/15] PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller

[Frank Li]

Doorbell feature is implemented by mapping the EP's MSI interrupt
controller message address to a dedicated BAR in the EPC core. It is the
responsibility of the EPF driver to pass the actual message data to be
written by the host to the doorbell BAR region through its own logic.

Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Change from v13 to v14
- basic roll back to v9
- use device:id as msi-map input, its will handle it
- use existed platform_device_msi_init_and_alloc_irqs()
- pass down epf->dev point, because epf->dev of-node will be the same as
epc's parent.

Change from v12 to v13
- Use DOMAIN_BUS_DEVICE_PCI_EP_MSI

Change from v10 to v12
- none

Change from v9 to v10
- Create msi domain for each function device.
- Remove only function support limiation. My hardware only support one
function, so not test more than one case.
- use "msi-map" descript msi information

  msi-map = <func_no << 8  | vfunc_no, &its, start_stream_id,  size>;

Chagne from v8 to v9
- sort header file
- use pci_epc_get(dev_name(msi_desc_to_dev(desc)));
- check epf number at pci_epf_alloc_doorbell
- Add comments for miss msi-parent case

change from v5 to v8
-none

Change from v4 to v5
- Remove request_irq() in pci_epc_alloc_doorbell() and leave to EP function
driver, so ep function driver can register differece call back function for
difference doorbell events and set irq affinity to differece CPU core.
- Improve error message when MSI allocate failure.

Change from v3 to v4
- msi change to use msi_get_virq() avoid use msi_for_each_desc().
- add new struct for pci_epf_doorbell_msg to msi msg,virq and irq name.
- move mutex lock to epc function
- initialize variable at declear place.
- passdown epf to epc*() function to simplify code.
---
 drivers/pci/endpoint/Makefile     |  2 +-
 drivers/pci/endpoint/pci-ep-msi.c | 81 +++++++++++++++++++++++++++++++++++++++
 include/linux/pci-ep-msi.h        | 26 +++++++++++++
 include/linux/pci-epf.h           | 16 ++++++++
 4 files changed, 124 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/endpoint/Makefile b/drivers/pci/endpoint/Makefile
index 95b2fe47e3b06..a1ccce440c2c5 100644
--- a/drivers/pci/endpoint/Makefile
+++ b/drivers/pci/endpoint/Makefile
@@ -5,4 +5,4 @@
 
 obj-$(CONFIG_PCI_ENDPOINT_CONFIGFS)	+= pci-ep-cfs.o
 obj-$(CONFIG_PCI_ENDPOINT)		+= pci-epc-core.o pci-epf-core.o\
-					   pci-epc-mem.o functions/
+					   pci-epc-mem.o pci-ep-msi.o functions/
diff --git a/drivers/pci/endpoint/pci-ep-msi.c b/drivers/pci/endpoint/pci-ep-msi.c
new file mode 100644
index 0000000000000..53820744ce502
--- /dev/null
+++ b/drivers/pci/endpoint/pci-ep-msi.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI Endpoint *Controller* (EPC) MSI library
+ *
+ * Copyright (C) 2025 NXP
+ * Author: Frank Li <Frank.Li@nxp.com>
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_irq.h>
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+#include <linux/pci-ep-cfs.h>
+#include <linux/pci-ep-msi.h>
+#include <linux/slab.h>
+
+static void pci_epf_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+	struct pci_epf *epf = to_pci_epf(desc->dev);
+
+	if (epf && epf->db_msg && desc->msi_index < epf->num_db)
+		memcpy(&epf->db_msg[desc->msi_index].msg, msg, sizeof(*msg));
+}
+
+int pci_epf_alloc_doorbell(struct pci_epf *epf, u16 num_db)
+{
+	struct pci_epc *epc = epf->epc;
+	struct device *dev = &epf->dev;
+	struct irq_domain *dom;
+	void *msg;
+	u32 rid;
+	int ret;
+	int i;
+
+	rid = PCI_EPF_DEVID(epf->func_no, epf->vfunc_no);
+	dom = of_msi_map_get_device_domain(epc->dev.parent, rid, DOMAIN_BUS_PLATFORM_MSI);
+	if (!dom) {
+		dev_err(dev, "Can't find msi domain\n");
+		return -EINVAL;
+	}
+
+	dev_set_msi_domain(dev, dom);
+
+	msg = kcalloc(num_db, sizeof(struct pci_epf_doorbell_msg), GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	epf->num_db = num_db;
+	epf->db_msg = msg;
+
+	ret = platform_device_msi_init_and_alloc_irqs(&epf->dev, num_db, pci_epf_write_msi_msg);
+	if (ret) {
+		/*
+		 * The pcie_ep DT node has to specify 'msi-parent' for EP
+		 * doorbell support to work. Right now only GIC ITS is
+		 * supported. If you have GIC ITS and reached this print,
+		 * perhaps you are missing 'msi-map' in DT.
+		 */
+		dev_err(dev, "Failed to allocate MSI\n");
+		kfree(msg);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < num_db; i++)
+		epf->db_msg[i].virq = msi_get_virq(dev, i);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pci_epf_alloc_doorbell);
+
+void pci_epf_free_doorbell(struct pci_epf *epf)
+{
+	platform_device_msi_free_irqs_all(&epf->dev);
+
+	kfree(epf->db_msg);
+	epf->db_msg = NULL;
+	epf->num_db = 0;
+}
+EXPORT_SYMBOL_GPL(pci_epf_free_doorbell);
diff --git a/include/linux/pci-ep-msi.h b/include/linux/pci-ep-msi.h
new file mode 100644
index 0000000000000..26b1c86893ee4
--- /dev/null
+++ b/include/linux/pci-ep-msi.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * PCI Endpoint *Function* side MSI header file
+ *
+ * Copyright (C) 2024 NXP
+ * Author: Frank Li <Frank.Li@nxp.com>
+ */
+
+#ifndef __PCI_EP_MSI__
+#define __PCI_EP_MSI__
+
+#ifdef CONFIG_PCI_ENDPOINT
+int pci_epf_msi_domain_get_msi_rid(struct device *dev, u32 *rid);
+#else
+static inline int pci_epf_msi_domain_get_msi_rid(struct device *dev, u32 *rid)
+{
+	return -EINVAL;
+}
+#endif
+
+struct pci_epf;
+
+int pci_epf_alloc_doorbell(struct pci_epf *epf, u16 nums);
+void pci_epf_free_doorbell(struct pci_epf *epf);
+
+#endif /* __PCI_EP_MSI__ */
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index d2790b8b29394..518bc4171285e 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -12,6 +12,7 @@
 #include <linux/configfs.h>
 #include <linux/device.h>
 #include <linux/mod_devicetable.h>
+#include <linux/msi.h>
 #include <linux/pci.h>
 
 struct pci_epf;
@@ -125,6 +126,17 @@ struct pci_epf_bar {
 	int		flags;
 };
 
+/**
+ * struct pci_epf_doorbell_msg - represents doorbell message
+ * @msi_msg: MSI message
+ * @virq: irq number of this doorbell MSI message
+ * @name: irq name for doorbell interrupt
+ */
+struct pci_epf_doorbell_msg {
+	struct msi_msg msg;
+	int virq;
+};
+
 /**
  * struct pci_epf - represents the PCI EPF device
  * @dev: the PCI EPF device
@@ -152,6 +164,8 @@ struct pci_epf_bar {
  * @vfunction_num_map: bitmap to manage virtual function number
  * @pci_vepf: list of virtual endpoint functions associated with this function
  * @event_ops: Callbacks for capturing the EPC events
+ * @db_msg: data for MSI from RC side
+ * @num_db: number of doorbells
  */
 struct pci_epf {
 	struct device		dev;
@@ -182,6 +196,8 @@ struct pci_epf {
 	unsigned long		vfunction_num_map;
 	struct list_head	pci_vepf;
 	const struct pci_epc_event_ops *event_ops;
+	struct pci_epf_doorbell_msg *db_msg;
+	u16 num_db;
 };
 
 /**

-- 
2.34.1

[PATCH v14 07/15] PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check

[Frank Li]

Some MSI controller change address/data pair when irq_set_affinity().
Current PCI endpoint can't support this type MSI controller. So add flag
MSI_FLAG_MUTABLE in include/linux/msi.h and check it when allocate
doorbell.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change fomr v13 to v14
- bring v10 back

Change from v9 to v10
- new patch
---
 drivers/pci/endpoint/pci-ep-msi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/pci/endpoint/pci-ep-msi.c b/drivers/pci/endpoint/pci-ep-msi.c
index 53820744ce502..e3ec53c2fefbe 100644
--- a/drivers/pci/endpoint/pci-ep-msi.c
+++ b/drivers/pci/endpoint/pci-ep-msi.c
@@ -43,6 +43,14 @@ int pci_epf_alloc_doorbell(struct pci_epf *epf, u16 num_db)
 
 	dev_set_msi_domain(dev, dom);
 
+	if (!irq_domain_is_msi_parent(dom))
+		return -EINVAL;
+
+	if (!irq_domain_is_msi_immutable(dom)) {
+		dev_err(dev, "Can't support mutable address/data pair MSI controller\n");
+		return -EINVAL;
+	}
+
 	msg = kcalloc(num_db, sizeof(struct pci_epf_doorbell_msg), GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;

-- 
2.34.1

[PATCH v14 08/15] PCI: endpoint: Add pci_epf_align_inbound_addr() helper for address alignment

[Frank Li]

Introduce the helper function pci_epf_align_inbound_addr() to adjust
addresses according to PCI BAR alignment requirements, converting addresses
into base and offset values.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Change form v9 to v14
- none

change from v8 to v9
- pci_epf_align_inbound_addr(), base and off must be not NULL
- rm pci_epf_align_inbound_addr_lo_hi()

change from v7 to v8
- change name to pci_epf_align_inbound_addr()
- update comment said only need for memory, which not allocated by
pci_epf_alloc_space().

change from v6 to v7
- new patch
---
 drivers/pci/endpoint/pci-epf-core.c | 44 +++++++++++++++++++++++++++++++++++++
 include/linux/pci-epf.h             |  3 +++
 2 files changed, 47 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index f728ee2660a4e..04facefc70423 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -469,6 +469,50 @@ struct pci_epf *pci_epf_create(const char *name)
 }
 EXPORT_SYMBOL_GPL(pci_epf_create);
 
+/**
+ * pci_epf_align_inbound_addr() - Get base address and offset that match BAR's
+ *			  alignment requirement
+ * @epf: the EPF device
+ * @addr: the address of the memory
+ * @bar: the BAR number corresponding to map addr
+ * @base: return base address, which match BAR's alignment requirement.
+ * @off: return offset.
+ *
+ * Helper function to convert input 'addr' to base and offset, which match
+ * BAR's alignment requirement.
+ *
+ * The pci_epf_alloc_space() function already accounts for alignment. This is
+ * primarily intended for use with other memory regions not allocated by
+ * pci_epf_alloc_space(), such as peripheral register spaces or the trigger
+ * address for a platform MSI controller.
+ */
+int pci_epf_align_inbound_addr(struct pci_epf *epf, enum pci_barno bar,
+			       u64 addr, u64 *base, size_t *off)
+{
+	const struct pci_epc_features *epc_features;
+	u64 align;
+
+	if (!base || !off)
+		return -EINVAL;
+
+	epc_features = pci_epc_get_features(epf->epc, epf->func_no, epf->vfunc_no);
+	if (!epc_features) {
+		dev_err(&epf->dev, "epc_features not implemented\n");
+		return -EOPNOTSUPP;
+	}
+
+	align = epc_features->align;
+	align = align ? align : 128;
+	if (epc_features->bar[bar].type == BAR_FIXED)
+		align = max(epc_features->bar[bar].fixed_size, align);
+
+	*base = round_down(addr, align);
+	*off = addr & (align - 1);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pci_epf_align_inbound_addr);
+
 static void pci_epf_dev_release(struct device *dev)
 {
 	struct pci_epf *epf = to_pci_epf(dev);
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index 518bc4171285e..1a5cc4d4ae362 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -240,6 +240,9 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
 			  enum pci_epc_interface_type type);
 void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar,
 			enum pci_epc_interface_type type);
+
+int pci_epf_align_inbound_addr(struct pci_epf *epf, enum pci_barno bar,
+			       u64 addr, u64 *base, size_t *off);
 int pci_epf_bind(struct pci_epf *epf);
 void pci_epf_unbind(struct pci_epf *epf);
 int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf);

-- 
2.34.1

[PATCH v14 09/15] PCI: endpoint: pci-epf-test: Add doorbell test support

[Frank Li]

Add three registers: doorbell_bar, doorbell_addr, and doorbell_data. Use
pci_epf_alloc_doorbell() to allocate a doorbell address space.

Enable the Root Complex (RC) side driver to trigger pci-epc-test's doorbell
callback handler by writing doorbell_data to the mapped doorbell_bar's
address space.

Set STATUS_DOORBELL_SUCCESS in the doorbell callback to indicate
completion.

Avoid breaking compatibility between host and endpoint, add new command
COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL. Host side need send
COMMAND_ENABLE_DOORBELL to map one bar's inbound address to MSI space.
the command COMMAND_DISABLE_DOORBELL to recovery original inbound address
mapping.

	 	Host side new driver	Host side old driver

EP: new driver      S				F
EP: old driver      F				F

S: If EP side support MSI, 'pci_endpoint_test -f pcie_ep_doorbell' return
success.
   If EP side doesn't support MSI, the same to 'F'.

F: 'pci_endpoint_test -f pcie_ep_doorbell' return failure, other case as
usual.

Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Change from v9 to v14
- update commit message by use pci_endpoint_test -f pcie_ep_doorbell

Change from v8 to v9
- move pci_epf_alloc_doorbell() into pci_epf_{enable/disable}_doorbell().
- remove doorbell_done in commit message.
- rename pci_epf_{enable/disable}_doorbell() to
pci_epf_test_{enable/disable}_doorbell() to align corrent code style.

Change from v7 to v8
- rename to pci_epf_align_inbound_addr_lo_hi()

Change from v6 to v7
- use help function pci_epf_align_addr_lo_hi()

Change from v5 to v6
- rename doorbell_addr to doorbell_offset

Chagne from v4 to v5
- Add doorbell free at unbind function.
- Move msi irq handler to here to more complex user case, such as differece
doorbell can use difference handler function.
- Add Niklas's code to handle fixed bar's case. If need add your signed-off
tag or co-developer tag, please let me know.

change from v3 to v4
- remove revid requirement
- Add command COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL.
- call pci_epc_set_bar() to map inbound address to MSI space only at
COMMAND_ENABLE_DOORBELL.
---
 drivers/pci/endpoint/functions/pci-epf-test.c | 132 ++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index b94e205ae10b9..bba1229c46f14 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -11,12 +11,14 @@
 #include <linux/dmaengine.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/msi.h>
 #include <linux/slab.h>
 #include <linux/pci_ids.h>
 #include <linux/random.h>
 
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
+#include <linux/pci-ep-msi.h>
 #include <linux/pci_regs.h>
 
 #define IRQ_TYPE_INTX			0
@@ -29,6 +31,8 @@
 #define COMMAND_READ			BIT(3)
 #define COMMAND_WRITE			BIT(4)
 #define COMMAND_COPY			BIT(5)
+#define COMMAND_ENABLE_DOORBELL		BIT(6)
+#define COMMAND_DISABLE_DOORBELL	BIT(7)
 
 #define STATUS_READ_SUCCESS		BIT(0)
 #define STATUS_READ_FAIL		BIT(1)
@@ -39,6 +43,11 @@
 #define STATUS_IRQ_RAISED		BIT(6)
 #define STATUS_SRC_ADDR_INVALID		BIT(7)
 #define STATUS_DST_ADDR_INVALID		BIT(8)
+#define STATUS_DOORBELL_SUCCESS		BIT(9)
+#define STATUS_DOORBELL_ENABLE_SUCCESS	BIT(10)
+#define STATUS_DOORBELL_ENABLE_FAIL	BIT(11)
+#define STATUS_DOORBELL_DISABLE_SUCCESS BIT(12)
+#define STATUS_DOORBELL_DISABLE_FAIL	BIT(13)
 
 #define FLAG_USE_DMA			BIT(0)
 
@@ -63,6 +72,7 @@ struct pci_epf_test {
 	bool			dma_supported;
 	bool			dma_private;
 	const struct pci_epc_features *epc_features;
+	struct pci_epf_bar	db_bar;
 };
 
 struct pci_epf_test_reg {
@@ -77,6 +87,9 @@ struct pci_epf_test_reg {
 	u32	irq_number;
 	u32	flags;
 	u32	caps;
+	u32	doorbell_bar;
+	u32	doorbell_offset;
+	u32	doorbell_data;
 } __packed;
 
 static struct pci_epf_header test_header = {
@@ -645,6 +658,116 @@ static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test,
 	}
 }
 
+static irqreturn_t pci_epf_test_doorbell_handler(int irq, void *data)
+{
+	struct pci_epf_test *epf_test = data;
+	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
+	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
+
+	reg->status |= STATUS_DOORBELL_SUCCESS;
+	pci_epf_test_raise_irq(epf_test, reg);
+
+	return IRQ_HANDLED;
+}
+
+static void pci_epf_test_doorbell_cleanup(struct pci_epf_test *epf_test)
+{
+	struct pci_epf_test_reg *reg = epf_test->reg[epf_test->test_reg_bar];
+	struct pci_epf *epf = epf_test->epf;
+
+	if (reg->doorbell_bar > 0) {
+		free_irq(epf->db_msg[0].virq, epf_test);
+		reg->doorbell_bar = NO_BAR;
+	}
+
+	if (epf->db_msg)
+		pci_epf_free_doorbell(epf);
+}
+
+static void pci_epf_test_enable_doorbell(struct pci_epf_test *epf_test,
+					 struct pci_epf_test_reg *reg)
+{
+	struct pci_epf *epf = epf_test->epf;
+	struct pci_epc *epc = epf->epc;
+	struct msi_msg *msg;
+	enum pci_barno bar;
+	size_t offset;
+	int ret;
+
+	ret = pci_epf_alloc_doorbell(epf, 1);
+	if (ret) {
+		reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
+		return;
+	}
+
+	msg = &epf->db_msg[0].msg;
+	bar = pci_epc_get_next_free_bar(epf_test->epc_features, epf_test->test_reg_bar + 1);
+	if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) {
+		reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
+		return;
+	}
+
+	ret = request_irq(epf->db_msg[0].virq, pci_epf_test_doorbell_handler, 0,
+			  "pci-test-doorbell", epf_test);
+	if (ret) {
+		dev_err(&epf->dev,
+			"Failed to request irq %d, doorbell feature is not supported\n",
+			epf->db_msg[0].virq);
+		reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
+		pci_epf_test_doorbell_cleanup(epf_test);
+		return;
+	}
+
+	reg->doorbell_data = msg->data;
+	reg->doorbell_bar = bar;
+
+	msg = &epf->db_msg[0].msg;
+	ret = pci_epf_align_inbound_addr(epf, bar, ((u64)msg->address_hi << 32) | msg->address_lo,
+					 &epf_test->db_bar.phys_addr, &offset);
+
+	if (ret) {
+		reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
+		pci_epf_test_doorbell_cleanup(epf_test);
+		return;
+	}
+
+	reg->doorbell_offset = offset;
+
+	epf_test->db_bar.barno = bar;
+	epf_test->db_bar.size = epf->bar[bar].size;
+	epf_test->db_bar.flags = epf->bar[bar].flags;
+
+	ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &epf_test->db_bar);
+	if (ret) {
+		reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
+		pci_epf_test_doorbell_cleanup(epf_test);
+	} else {
+		reg->status |= STATUS_DOORBELL_ENABLE_SUCCESS;
+	}
+}
+
+static void pci_epf_test_disable_doorbell(struct pci_epf_test *epf_test,
+					  struct pci_epf_test_reg *reg)
+{
+	enum pci_barno bar = reg->doorbell_bar;
+	struct pci_epf *epf = epf_test->epf;
+	struct pci_epc *epc = epf->epc;
+	int ret;
+
+	if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) {
+		reg->status |= STATUS_DOORBELL_DISABLE_FAIL;
+		return;
+	}
+
+	ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &epf->bar[bar]);
+	if (ret)
+		reg->status |= STATUS_DOORBELL_DISABLE_FAIL;
+	else
+		reg->status |= STATUS_DOORBELL_DISABLE_SUCCESS;
+
+	pci_epf_test_doorbell_cleanup(epf_test);
+}
+
 static void pci_epf_test_cmd_handler(struct work_struct *work)
 {
 	u32 command;
@@ -691,6 +814,14 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
 		pci_epf_test_copy(epf_test, reg);
 		pci_epf_test_raise_irq(epf_test, reg);
 		break;
+	case COMMAND_ENABLE_DOORBELL:
+		pci_epf_test_enable_doorbell(epf_test, reg);
+		pci_epf_test_raise_irq(epf_test, reg);
+		break;
+	case COMMAND_DISABLE_DOORBELL:
+		pci_epf_test_disable_doorbell(epf_test, reg);
+		pci_epf_test_raise_irq(epf_test, reg);
+		break;
 	default:
 		dev_err(dev, "Invalid command 0x%x\n", command);
 		break;
@@ -953,6 +1084,7 @@ static void pci_epf_test_unbind(struct pci_epf *epf)
 		pci_epf_test_clean_dma_chan(epf_test);
 		pci_epf_test_clear_bar(epf);
 	}
+	pci_epf_test_doorbell_cleanup(epf_test);
 	pci_epf_test_free_space(epf);
 }
 

-- 
2.34.1

[PATCH v14 10/15] misc: pci_endpoint_test: Add doorbell test case

[Frank Li]

Add three registers: PCIE_ENDPOINT_TEST_DB_BAR, PCIE_ENDPOINT_TEST_DB_ADDR,
and PCIE_ENDPOINT_TEST_DB_DATA.

Trigger the doorbell by writing data from PCI_ENDPOINT_TEST_DB_DATA to the
address provided by PCI_ENDPOINT_TEST_DB_OFFSET and wait for endpoint
feedback.

Add two command to COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL
to enable EP side's doorbell support and avoid compatible problem, which
host side driver miss-match with endpoint side function driver. See below
table:

		Host side new driver	Host side old driver
EP: new driver		S			F
EP: old driver		F			F

S: If EP side support MSI, 'pci_endpoint_test -f pcie_ep_doorbell' return
success.
   If EP side doesn't support MSI, the same to 'F'.

F: 'pci_endpoint_test -f pcie_ep_doorbell' return failure, other case as
usual.

Tested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
Change from v13 to v14
- update to use pci_endpoint_test -f pcie_ep_doorbell
- change ioctrl id to fix conflict

Change from v9 to v13
- none

Change from v8 to v9
- change PCITEST_DOORBELL to 0xa

Change form v6 to v8
- none

Change from v5 to v6
- %s/PCI_ENDPOINT_TEST_DB_ADDR/PCI_ENDPOINT_TEST_DB_OFFSET/g

Change from v4 to v5
- remove unused varible
- add irq_type at pci_endpoint_test_doorbell();

change from v3 to v4
- Add COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL.
- Remove new DID requirement.
---
 drivers/misc/pci_endpoint_test.c | 81 ++++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/pcitest.h     |  1 +
 2 files changed, 82 insertions(+)

diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
index d5ac71a493865..7ac021bcc7152 100644
--- a/drivers/misc/pci_endpoint_test.c
+++ b/drivers/misc/pci_endpoint_test.c
@@ -42,6 +42,8 @@
 #define COMMAND_READ				BIT(3)
 #define COMMAND_WRITE				BIT(4)
 #define COMMAND_COPY				BIT(5)
+#define COMMAND_ENABLE_DOORBELL			BIT(6)
+#define COMMAND_DISABLE_DOORBELL		BIT(7)
 
 #define PCI_ENDPOINT_TEST_STATUS		0x8
 #define STATUS_READ_SUCCESS			BIT(0)
@@ -53,6 +55,11 @@
 #define STATUS_IRQ_RAISED			BIT(6)
 #define STATUS_SRC_ADDR_INVALID			BIT(7)
 #define STATUS_DST_ADDR_INVALID			BIT(8)
+#define STATUS_DOORBELL_SUCCESS			BIT(9)
+#define STATUS_DOORBELL_ENABLE_SUCCESS		BIT(10)
+#define STATUS_DOORBELL_ENABLE_FAIL		BIT(11)
+#define STATUS_DOORBELL_DISABLE_SUCCESS		BIT(12)
+#define STATUS_DOORBELL_DISABLE_FAIL		BIT(13)
 
 #define PCI_ENDPOINT_TEST_LOWER_SRC_ADDR	0x0c
 #define PCI_ENDPOINT_TEST_UPPER_SRC_ADDR	0x10
@@ -67,11 +74,16 @@
 #define PCI_ENDPOINT_TEST_IRQ_NUMBER		0x28
 
 #define PCI_ENDPOINT_TEST_FLAGS			0x2c
+
 #define FLAG_USE_DMA				BIT(0)
 
 #define PCI_ENDPOINT_TEST_CAPS			0x30
 #define CAP_UNALIGNED_ACCESS			BIT(0)
 
+#define PCI_ENDPOINT_TEST_DB_BAR		0x34
+#define PCI_ENDPOINT_TEST_DB_OFFSET		0x38
+#define PCI_ENDPOINT_TEST_DB_DATA		0x3c
+
 #define PCI_DEVICE_ID_TI_AM654			0xb00c
 #define PCI_DEVICE_ID_TI_J7200			0xb00f
 #define PCI_DEVICE_ID_TI_AM64			0xb010
@@ -111,6 +123,7 @@ enum pci_barno {
 	BAR_3,
 	BAR_4,
 	BAR_5,
+	NO_BAR = -1,
 };
 
 struct pci_endpoint_test {
@@ -829,6 +842,71 @@ static int pci_endpoint_test_set_irq(struct pci_endpoint_test *test,
 	return 0;
 }
 
+static int pci_endpoint_test_doorbell(struct pci_endpoint_test *test)
+{
+	struct pci_dev *pdev = test->pdev;
+	struct device *dev = &pdev->dev;
+	int irq_type = test->irq_type;
+	enum pci_barno bar;
+	u32 data, status;
+	u32 addr;
+
+	if (irq_type < IRQ_TYPE_INTX || irq_type > IRQ_TYPE_MSIX) {
+		dev_err(dev, "Invalid IRQ type option\n");
+		return -EINVAL;
+	}
+
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_TYPE, irq_type);
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_NUMBER, 1);
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+				 COMMAND_ENABLE_DOORBELL);
+
+	wait_for_completion_timeout(&test->irq_raised, msecs_to_jiffies(1000));
+
+	status = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS);
+	if (status & STATUS_DOORBELL_ENABLE_FAIL) {
+		dev_err(dev, "Failed to enable doorbell\n");
+		return -EINVAL;
+	}
+
+	data = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_DATA);
+	addr = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_OFFSET);
+	bar = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_BAR);
+
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_TYPE, irq_type);
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_NUMBER, 1);
+
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_STATUS, 0);
+
+	bar = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_BAR);
+
+	writel(data, test->bar[bar] + addr);
+
+	wait_for_completion_timeout(&test->irq_raised, msecs_to_jiffies(1000));
+
+	status = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS);
+
+	if (!(status & STATUS_DOORBELL_SUCCESS))
+		dev_err(dev, "Endpoint have not received Doorbell\n");
+
+	pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+				 COMMAND_DISABLE_DOORBELL);
+
+	wait_for_completion_timeout(&test->irq_raised, msecs_to_jiffies(1000));
+
+	status |= pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS);
+
+	if (status & STATUS_DOORBELL_DISABLE_FAIL) {
+		dev_err(dev, "Failed to disable doorbell\n");
+		return -EINVAL;
+	}
+
+	if (!(status & STATUS_DOORBELL_SUCCESS))
+		return -EINVAL;
+
+	return 0;
+}
+
 static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
 				    unsigned long arg)
 {
@@ -879,6 +957,9 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
 	case PCITEST_CLEAR_IRQ:
 		ret = pci_endpoint_test_clear_irq(test);
 		break;
+	case PCITEST_DOORBELL:
+		ret = pci_endpoint_test_doorbell(test);
+		break;
 	}
 
 ret:
diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h
index acd261f498666..80f4c0e05679b 100644
--- a/include/uapi/linux/pcitest.h
+++ b/include/uapi/linux/pcitest.h
@@ -21,6 +21,7 @@
 #define PCITEST_SET_IRQTYPE	_IOW('P', 0x8, int)
 #define PCITEST_GET_IRQTYPE	_IO('P', 0x9)
 #define PCITEST_BARS		_IO('P', 0xa)
+#define PCITEST_DOORBELL	_IO('P', 0xb)
 #define PCITEST_CLEAR_IRQ	_IO('P', 0x10)
 
 #define PCITEST_FLAGS_USE_DMA	0x00000001

-- 
2.34.1

[PATCH v14 11/15] selftests: pci_endpoint: Add doorbell test case

[Frank Li]

Add doorbell test case.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- merge to selftests framework
---
 .../selftests/pci_endpoint/pci_endpoint_test.c     | 25 ++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/tools/testing/selftests/pci_endpoint/pci_endpoint_test.c b/tools/testing/selftests/pci_endpoint/pci_endpoint_test.c
index c267b822c1081..ed14c9fa073f9 100644
--- a/tools/testing/selftests/pci_endpoint/pci_endpoint_test.c
+++ b/tools/testing/selftests/pci_endpoint/pci_endpoint_test.c
@@ -218,4 +218,29 @@ TEST_F(pci_ep_data_transfer, COPY_TEST)
 					 test_size[i]);
 	}
 }
+
+FIXTURE(pcie_ep_doorbell)
+{
+	int fd;
+};
+
+FIXTURE_SETUP(pcie_ep_doorbell)
+{
+	self->fd = open(test_device, O_RDWR);
+
+	ASSERT_NE(-1, self->fd) TH_LOG("Can't open PCI Endpoint Test device");
+};
+
+FIXTURE_TEARDOWN(pcie_ep_doorbell)
+{
+	close(self->fd);
+};
+
+TEST_F(pcie_ep_doorbell, DOORBELL_TEST)
+{
+	int ret;
+
+	pci_ep_ioctl(PCITEST_DOORBELL, 0);
+	EXPECT_FALSE(ret) TH_LOG("Test failed for Doorbell\n");
+}
 TEST_HARNESS_MAIN

-- 
2.34.1

[PATCH v14 12/15] pci: imx6: Add helper function imx_pcie_add_lut_by_rid()

[Frank Li]

Add helper function imx_pcie_add_lut_by_rid(), which will be used for
Endpoint mode in the future. No functional change.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- new patch
---
 drivers/pci/controller/dwc/pci-imx6.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 90ace941090f9..e20d91988c718 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1028,18 +1028,14 @@ static void imx_pcie_remove_lut(struct imx_pcie *imx_pcie, u16 rid)
 	}
 }
 
-static int imx_pcie_enable_device(struct pci_host_bridge *bridge,
-				  struct pci_dev *pdev)
+static int imx_pcie_add_lut_by_rid(struct imx_pcie *imx_pcie, u32 rid)
 {
-	struct imx_pcie *imx_pcie = to_imx_pcie(to_dw_pcie_from_pp(bridge->sysdata));
-	u32 sid_i, sid_m, rid = pci_dev_id(pdev);
+	struct device *dev = imx_pcie->pci->dev;
 	struct device_node *target;
-	struct device *dev;
+	u32 sid_i, sid_m;
 	int err_i, err_m;
 	u32 sid = 0;
 
-	dev = imx_pcie->pci->dev;
-
 	target = NULL;
 	err_i = of_map_id(dev->of_node, rid, "iommu-map", "iommu-map-mask",
 			  &target, &sid_i);
@@ -1114,6 +1110,13 @@ static int imx_pcie_enable_device(struct pci_host_bridge *bridge,
 	return imx_pcie_add_lut(imx_pcie, rid, sid);
 }
 
+static int imx_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_dev *pdev)
+{
+	struct imx_pcie *imx_pcie = to_imx_pcie(to_dw_pcie_from_pp(bridge->sysdata));
+
+	return imx_pcie_add_lut_by_rid(imx_pcie, pci_dev_id(pdev));
+}
+
 static void imx_pcie_disable_device(struct pci_host_bridge *bridge,
 				    struct pci_dev *pdev)
 {

-- 
2.34.1

[PATCH v14 13/15] pci: imx6: Add LUT setting for MSI/IOMMU in Endpoint mode

[Frank Li]

Support only one physical function, so call imx_pcie_add_lut_by_rid(0)
to add a single LUT entry when operating in EP mode.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- new patch
---
 drivers/pci/controller/dwc/pci-imx6.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index e20d91988c718..adcca3e644332 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -995,7 +995,10 @@ static int imx_pcie_add_lut(struct imx_pcie *imx_pcie, u16 rid, u8 sid)
 	data1 |= IMX95_PE0_LUT_VLD;
 	regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA1, data1);
 
-	data2 = IMX95_PE0_LUT_MASK; /* Match all bits of RID */
+	if (imx_pcie->drvdata->mode == DW_PCIE_EP_TYPE)
+		data2 = 0x7; /* EP side's RID from RC, only 'D' is meansful */
+	else
+		data2 = IMX95_PE0_LUT_MASK; /* Match all bits of RID */
 	data2 |= FIELD_PREP(IMX95_PE0_LUT_REQID, rid);
 	regmap_write(imx_pcie->iomuxc_gpr, IMX95_PE0_LUT_DATA2, data2);
 
@@ -1652,6 +1655,9 @@ static int imx_pcie_probe(struct platform_device *pdev)
 		ret = imx_add_pcie_ep(imx_pcie, pdev);
 		if (ret < 0)
 			return ret;
+
+		/* Only support one physical function */
+		imx_pcie_add_lut_by_rid(imx_pcie, 0);
 	} else {
 		pci->pp.use_atu_msg = true;
 		ret = dw_pcie_host_init(&pci->pp);

-- 
2.34.1

[PATCH v14 14/15] arm64: dts: imx95: Add msi-map for pci-ep device

[Frank Li]

Add msi-map for pci-ep device.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- new patch
---
 arch/arm64/boot/dts/freescale/imx95.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/freescale/imx95.dtsi b/arch/arm64/boot/dts/freescale/imx95.dtsi
index 6b8470cb3461a..cdc06dea5982b 100644
--- a/arch/arm64/boot/dts/freescale/imx95.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx95.dtsi
@@ -1667,6 +1667,7 @@ pcie1_ep: pcie-ep@4c380000 {
 			assigned-clock-rates = <3600000000>, <100000000>, <10000000>;
 			assigned-clock-parents = <0>, <0>,
 						 <&scmi_clk IMX95_CLK_SYSPLL1_PFD1_DIV2>;
+			msi-map = <0x0 &its 0x98 0x1>;
 			power-domains = <&scmi_devpd IMX95_PD_HSIO_TOP>;
 			status = "disabled";
 		};

-- 
2.34.1

[PATCH v14 15/15] arm64: dts: imx95-19x19-evk: Add PCIe1 endpoint function overlay file

[Frank Li]

Add an overlay file to configure PCIe1 to function as an endpoint. Enable
PCIe1 to work as endpoint mode on the imx95-19x19-evk platform.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v13 to v14
- new patch
---
 arch/arm64/boot/dts/freescale/Makefile              |  3 +++
 .../dts/freescale/imx95-19x19-evk-pcie1-ep.dtso     | 21 +++++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/Makefile b/arch/arm64/boot/dts/freescale/Makefile
index 839432153cc7a..d892303fa7eab 100644
--- a/arch/arm64/boot/dts/freescale/Makefile
+++ b/arch/arm64/boot/dts/freescale/Makefile
@@ -287,6 +287,9 @@ imx8mm-kontron-dl-dtbs			:= imx8mm-kontron-bl.dtb imx8mm-kontron-dl.dtbo
 
 dtb-$(CONFIG_ARCH_MXC) += imx8mm-kontron-dl.dtb
 
+imx95-19x19-evk-pcie1-ep-dtbs += imx95-19x19-evk.dtb imx95-19x19-evk-pcie1-ep.dtbo
+dtb-$(CONFIG_ARCH_MXC) += imx95-19x19-evk-pcie1-ep.dtb
+
 imx8mm-venice-gw72xx-0x-imx219-dtbs	:= imx8mm-venice-gw72xx-0x.dtb imx8mm-venice-gw72xx-0x-imx219.dtbo
 imx8mm-venice-gw72xx-0x-rpidsi-dtbs	:= imx8mm-venice-gw72xx-0x.dtb imx8mm-venice-gw72xx-0x-rpidsi.dtbo
 imx8mm-venice-gw72xx-0x-rs232-rts-dtbs	:= imx8mm-venice-gw72xx-0x.dtb imx8mm-venice-gw72xx-0x-rs232-rts.dtbo
diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk-pcie1-ep.dtso b/arch/arm64/boot/dts/freescale/imx95-19x19-evk-pcie1-ep.dtso
new file mode 100644
index 0000000000000..696588e768e61
--- /dev/null
+++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk-pcie1-ep.dtso
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2024 NXP
+ */
+
+#include <dt-bindings/gpio/gpio.h>
+
+/dts-v1/;
+/plugin/;
+
+&pcie1 {
+	status = "disabled";
+};
+
+&pcie1_ep {
+	pinctrl-0 = <&pinctrl_pcie0>;
+	pinctrl-names = "default";
+	reset-gpio = <&i2c7_pcal6524 16 GPIO_ACTIVE_LOW>;
+	vpcie-supply = <&reg_slot_pwr>;
+	status = "okay";
+};

-- 
2.34.1

Re: [PATCH v14 06/15] PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller

[kernel test robot]

Hi Frank,

kernel test robot noticed the following build errors:

[auto build test ERROR on 00f3246adeeacbda0bd0b303604e46eb59c32e6e]

url:    https://github.com/intel-lab-lkp/linux/commits/Frank-Li/platform-msi-Add-msi_remove_device_irq_domain-in-platform_device_msi_free_irqs_all/20250208-034445
base:   00f3246adeeacbda0bd0b303604e46eb59c32e6e
patch link:    https://lore.kernel.org/r/20250207-ep-msi-v14-6-9671b136f2b8%40nxp.com
patch subject: [PATCH v14 06/15] PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller
config: i386-buildonly-randconfig-003-20250208 (https://download.01.org/0day-ci/archive/20250208/202502082204.6PRR3cfG-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250208/202502082204.6PRR3cfG-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/202502082204.6PRR3cfG-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/pci/endpoint/pci-ep-msi.c: In function 'pci_epf_alloc_doorbell':
>> drivers/pci/endpoint/pci-ep-msi.c:53:15: error: implicit declaration of function 'platform_device_msi_init_and_alloc_irqs' [-Werror=implicit-function-declaration]
      53 |         ret = platform_device_msi_init_and_alloc_irqs(&epf->dev, num_db, pci_epf_write_msi_msg);
         |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/pci/endpoint/pci-ep-msi.c: In function 'pci_epf_free_doorbell':
>> drivers/pci/endpoint/pci-ep-msi.c:75:9: error: implicit declaration of function 'platform_device_msi_free_irqs_all' [-Werror=implicit-function-declaration]
      75 |         platform_device_msi_free_irqs_all(&epf->dev);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/platform_device_msi_init_and_alloc_irqs +53 drivers/pci/endpoint/pci-ep-msi.c

    26	
    27	int pci_epf_alloc_doorbell(struct pci_epf *epf, u16 num_db)
    28	{
    29		struct pci_epc *epc = epf->epc;
    30		struct device *dev = &epf->dev;
    31		struct irq_domain *dom;
    32		void *msg;
    33		u32 rid;
    34		int ret;
    35		int i;
    36	
    37		rid = PCI_EPF_DEVID(epf->func_no, epf->vfunc_no);
    38		dom = of_msi_map_get_device_domain(epc->dev.parent, rid, DOMAIN_BUS_PLATFORM_MSI);
    39		if (!dom) {
    40			dev_err(dev, "Can't find msi domain\n");
    41			return -EINVAL;
    42		}
    43	
    44		dev_set_msi_domain(dev, dom);
    45	
    46		msg = kcalloc(num_db, sizeof(struct pci_epf_doorbell_msg), GFP_KERNEL);
    47		if (!msg)
    48			return -ENOMEM;
    49	
    50		epf->num_db = num_db;
    51		epf->db_msg = msg;
    52	
  > 53		ret = platform_device_msi_init_and_alloc_irqs(&epf->dev, num_db, pci_epf_write_msi_msg);
    54		if (ret) {
    55			/*
    56			 * The pcie_ep DT node has to specify 'msi-parent' for EP
    57			 * doorbell support to work. Right now only GIC ITS is
    58			 * supported. If you have GIC ITS and reached this print,
    59			 * perhaps you are missing 'msi-map' in DT.
    60			 */
    61			dev_err(dev, "Failed to allocate MSI\n");
    62			kfree(msg);
    63			return -ENOMEM;
    64		}
    65	
    66		for (i = 0; i < num_db; i++)
    67			epf->db_msg[i].virq = msi_get_virq(dev, i);
    68	
    69		return ret;
    70	}
    71	EXPORT_SYMBOL_GPL(pci_epf_alloc_doorbell);
    72	
    73	void pci_epf_free_doorbell(struct pci_epf *epf)
    74	{
  > 75		platform_device_msi_free_irqs_all(&epf->dev);

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Re: [PATCH v14 07/15] PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check

[kernel test robot]

Hi Frank,

kernel test robot noticed the following build errors:

[auto build test ERROR on 00f3246adeeacbda0bd0b303604e46eb59c32e6e]

url:    https://github.com/intel-lab-lkp/linux/commits/Frank-Li/platform-msi-Add-msi_remove_device_irq_domain-in-platform_device_msi_free_irqs_all/20250208-034445
base:   00f3246adeeacbda0bd0b303604e46eb59c32e6e
patch link:    https://lore.kernel.org/r/20250207-ep-msi-v14-7-9671b136f2b8%40nxp.com
patch subject: [PATCH v14 07/15] PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check
config: i386-buildonly-randconfig-003-20250208 (https://download.01.org/0day-ci/archive/20250208/202502082242.pOq1hB1d-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250208/202502082242.pOq1hB1d-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/202502082242.pOq1hB1d-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/pci/endpoint/pci-ep-msi.c: In function 'pci_epf_alloc_doorbell':
>> drivers/pci/endpoint/pci-ep-msi.c:49:14: error: implicit declaration of function 'irq_domain_is_msi_immutable'; did you mean 'irq_domain_is_msi_device'? [-Werror=implicit-function-declaration]
      49 |         if (!irq_domain_is_msi_immutable(dom)) {
         |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~
         |              irq_domain_is_msi_device
   drivers/pci/endpoint/pci-ep-msi.c:61:15: error: implicit declaration of function 'platform_device_msi_init_and_alloc_irqs' [-Werror=implicit-function-declaration]
      61 |         ret = platform_device_msi_init_and_alloc_irqs(&epf->dev, num_db, pci_epf_write_msi_msg);
         |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/pci/endpoint/pci-ep-msi.c: In function 'pci_epf_free_doorbell':
   drivers/pci/endpoint/pci-ep-msi.c:83:9: error: implicit declaration of function 'platform_device_msi_free_irqs_all' [-Werror=implicit-function-declaration]
      83 |         platform_device_msi_free_irqs_all(&epf->dev);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +49 drivers/pci/endpoint/pci-ep-msi.c

    26	
    27	int pci_epf_alloc_doorbell(struct pci_epf *epf, u16 num_db)
    28	{
    29		struct pci_epc *epc = epf->epc;
    30		struct device *dev = &epf->dev;
    31		struct irq_domain *dom;
    32		void *msg;
    33		u32 rid;
    34		int ret;
    35		int i;
    36	
    37		rid = PCI_EPF_DEVID(epf->func_no, epf->vfunc_no);
    38		dom = of_msi_map_get_device_domain(epc->dev.parent, rid, DOMAIN_BUS_PLATFORM_MSI);
    39		if (!dom) {
    40			dev_err(dev, "Can't find msi domain\n");
    41			return -EINVAL;
    42		}
    43	
    44		dev_set_msi_domain(dev, dom);
    45	
    46		if (!irq_domain_is_msi_parent(dom))
    47			return -EINVAL;
    48	
  > 49		if (!irq_domain_is_msi_immutable(dom)) {
    50			dev_err(dev, "Can't support mutable address/data pair MSI controller\n");
    51			return -EINVAL;
    52		}
    53	
    54		msg = kcalloc(num_db, sizeof(struct pci_epf_doorbell_msg), GFP_KERNEL);
    55		if (!msg)
    56			return -ENOMEM;
    57	
    58		epf->num_db = num_db;
    59		epf->db_msg = msg;
    60	
    61		ret = platform_device_msi_init_and_alloc_irqs(&epf->dev, num_db, pci_epf_write_msi_msg);
    62		if (ret) {
    63			/*
    64			 * The pcie_ep DT node has to specify 'msi-parent' for EP
    65			 * doorbell support to work. Right now only GIC ITS is
    66			 * supported. If you have GIC ITS and reached this print,
    67			 * perhaps you are missing 'msi-map' in DT.
    68			 */
    69			dev_err(dev, "Failed to allocate MSI\n");
    70			kfree(msg);
    71			return -ENOMEM;
    72		}
    73	
    74		for (i = 0; i < num_db; i++)
    75			epf->db_msg[i].virq = msi_get_virq(dev, i);
    76	
    77		return ret;
    78	}
    79	EXPORT_SYMBOL_GPL(pci_epf_alloc_doorbell);
    80	

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

Re: [PATCH v14 09/15] PCI: endpoint: pci-epf-test: Add doorbell test support

[kernel test robot]

Hi Frank,

kernel test robot noticed the following build errors:

[auto build test ERROR on 00f3246adeeacbda0bd0b303604e46eb59c32e6e]

url:    https://github.com/intel-lab-lkp/linux/commits/Frank-Li/platform-msi-Add-msi_remove_device_irq_domain-in-platform_device_msi_free_irqs_all/20250208-034445
base:   00f3246adeeacbda0bd0b303604e46eb59c32e6e
patch link:    https://lore.kernel.org/r/20250207-ep-msi-v14-9-9671b136f2b8%40nxp.com
patch subject: [PATCH v14 09/15] PCI: endpoint: pci-epf-test: Add doorbell test support
config: i386-buildonly-randconfig-003-20250208 (https://download.01.org/0day-ci/archive/20250208/202502082311.G1hWGggF-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250208/202502082311.G1hWGggF-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/202502082311.G1hWGggF-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/pci/endpoint/functions/pci-epf-test.c: In function 'pci_epf_test_enable_doorbell':
>> drivers/pci/endpoint/functions/pci-epf-test.c:726:42: error: passing argument 4 of 'pci_epf_align_inbound_addr' from incompatible pointer type [-Werror=incompatible-pointer-types]
     726 |                                          &epf_test->db_bar.phys_addr, &offset);
         |                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~
         |                                          |
         |                                          dma_addr_t * {aka unsigned int *}
   In file included from include/linux/pci-epc.h:12,
                    from drivers/pci/endpoint/functions/pci-epf-test.c:19:
   include/linux/pci-epf.h:245:47: note: expected 'u64 *' {aka 'long long unsigned int *'} but argument is of type 'dma_addr_t *' {aka 'unsigned int *'}
     245 |                                u64 addr, u64 *base, size_t *off);
         |                                          ~~~~~^~~~
   cc1: some warnings being treated as errors


vim +/pci_epf_align_inbound_addr +726 drivers/pci/endpoint/functions/pci-epf-test.c

   686	
   687	static void pci_epf_test_enable_doorbell(struct pci_epf_test *epf_test,
   688						 struct pci_epf_test_reg *reg)
   689	{
   690		struct pci_epf *epf = epf_test->epf;
   691		struct pci_epc *epc = epf->epc;
   692		struct msi_msg *msg;
   693		enum pci_barno bar;
   694		size_t offset;
   695		int ret;
   696	
   697		ret = pci_epf_alloc_doorbell(epf, 1);
   698		if (ret) {
   699			reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
   700			return;
   701		}
   702	
   703		msg = &epf->db_msg[0].msg;
   704		bar = pci_epc_get_next_free_bar(epf_test->epc_features, epf_test->test_reg_bar + 1);
   705		if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) {
   706			reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
   707			return;
   708		}
   709	
   710		ret = request_irq(epf->db_msg[0].virq, pci_epf_test_doorbell_handler, 0,
   711				  "pci-test-doorbell", epf_test);
   712		if (ret) {
   713			dev_err(&epf->dev,
   714				"Failed to request irq %d, doorbell feature is not supported\n",
   715				epf->db_msg[0].virq);
   716			reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
   717			pci_epf_test_doorbell_cleanup(epf_test);
   718			return;
   719		}
   720	
   721		reg->doorbell_data = msg->data;
   722		reg->doorbell_bar = bar;
   723	
   724		msg = &epf->db_msg[0].msg;
   725		ret = pci_epf_align_inbound_addr(epf, bar, ((u64)msg->address_hi << 32) | msg->address_lo,
 > 726						 &epf_test->db_bar.phys_addr, &offset);
   727	
   728		if (ret) {
   729			reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
   730			pci_epf_test_doorbell_cleanup(epf_test);
   731			return;
   732		}
   733	
   734		reg->doorbell_offset = offset;
   735	
   736		epf_test->db_bar.barno = bar;
   737		epf_test->db_bar.size = epf->bar[bar].size;
   738		epf_test->db_bar.flags = epf->bar[bar].flags;
   739	
   740		ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &epf_test->db_bar);
   741		if (ret) {
   742			reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
   743			pci_epf_test_doorbell_cleanup(epf_test);
   744		} else {
   745			reg->status |= STATUS_DOORBELL_ENABLE_SUCCESS;
   746		}
   747	}
   748	

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