[PATCH v10 00/10] PCI: qcom: Fix higher MSI vectors handling

[PATCH v10 00/10] PCI: qcom: Fix higher MSI vectors handling

[Dmitry Baryshkov]

 have replied with my Tested-by to the patch at [2], which has landed
in the linux-next as the commit 20f1bfb8dd62 ("PCI: qcom:
Add support for handling MSIs from 8 endpoints"). However lately I
noticed that during the tests I still had 'pcie_pme=nomsi', so the
device was not forced to use higher MSI vectors.

After removing this option I noticed that hight MSI vectors are not
delivered on tested platforms. After additional research I stumbled upon
a patch in msm-4.14 ([1]), which describes that each group of MSI
vectors is mapped to the separate interrupt. Implement corresponding
mapping.

The first patch in the series is a revert of  [2] (landed in pci-next).
Either both patches should be applied or both should be dropped.

Patchseries dependecies: [3] (for the schema change).

Changes since v9:
 - Relax requirements and stop validating the DT. If the has_split_msi
   was specified, parse as many msiN irqs as specified in DT. If there
   are none, fallback to the single "msi" IRQ.

Changes since v8:
 - Fix typos noted by Bjorn Helgaas
 - Add missing links to the patch 1 (revert)
 - Fix sm8250 interrupt-names (Johan)
 - Specify num_vectors in qcom configuration data (Johan)
 - Rework parsing of MSI IRQs (Johan)

Changes since v7:
 - Move code back to the dwc core driver (as required by Rob),
 - Change dt schema to require either a single "msi" interrupt or an
   array of "msi0", "msi1", ... "msi7" IRQs. Disallow specifying a
   part of the array (the DT should specify the exact amount of MSI IRQs
   allowing fallback to a single "msi" IRQ),
 - Fix in the DWC init code for the dma_mapping_error() return value.

Changes since v6:
 - Fix indentation of the arguments as requested by Stanimir

Changes since v5:
 - Fixed commit subject and in-comment code according to Bjorn's
   suggestion,
 - Changed variable idx to i to follow dw_handle_msi_irq() style.

Changes since v4:
 - Fix the minItems/maxItems properties in the YAML schema.

Changes since v3:
 - Reimplement MSI handling scheme in the Qualcomm host controller
   driver.

Changes since v2:
 - Fix and rephrase commit message for patch 2.

Changes since v1:
 - Split a huge patch into three patches as suggested by Bjorn Helgaas
 - snps,dw-pcie removal is now part of [3]

[1] https://git.codelinaro.org/clo/la/kernel/msm-4.14/-/commit/671a3d5f129f4bfe477152292ada2194c8440d22
[2] https://lore.kernel.org/linux-arm-msm/20211214101319.25258-1-manivannan.sadhasivam@linaro.org/
[3] https://lore.kernel.org/linux-arm-msm/20220422211002.2012070-1-dmitry.baryshkov@linaro.org/

Dmitry Baryshkov (10):
  PCI: qcom: Revert "PCI: qcom: Add support for handling MSIs from 8
    endpoints"
  PCI: dwc: Propagate error from dma_mapping_error()
  PCI: dwc: Correct msi_irq condition in dw_pcie_free_msi()
  PCI: dwc: Convert msi_irq to the array
  PCI: dwc: split MSI IRQ parsing/allocation to a separate function
  PCI: dwc: Handle MSIs routed to multiple GIC interrupts
  PCI: dwc: Implement special ISR handler for split MSI IRQ setup
  PCI: qcom: Handle MSIs routed to multiple GIC interrupts
  dt-bindings: PCI: qcom: Support additional MSI interrupts
  arm64: dts: qcom: sm8250: provide additional MSI interrupts

 .../devicetree/bindings/pci/qcom,pcie.yaml    |  53 ++++-
 arch/arm64/boot/dts/qcom/sm8250.dtsi          |  12 +-
 drivers/pci/controller/dwc/pci-dra7xx.c       |   2 +-
 drivers/pci/controller/dwc/pci-exynos.c       |   2 +-
 .../pci/controller/dwc/pcie-designware-host.c | 220 +++++++++++++-----
 drivers/pci/controller/dwc/pcie-designware.h  |   3 +-
 drivers/pci/controller/dwc/pcie-keembay.c     |   2 +-
 drivers/pci/controller/dwc/pcie-qcom.c        |  13 +-
 drivers/pci/controller/dwc/pcie-spear13xx.c   |   2 +-
 drivers/pci/controller/dwc/pcie-tegra194.c    |   2 +-
 10 files changed, 238 insertions(+), 73 deletions(-)

-- 
2.35.1

[PATCH v10 01/10] PCI: qcom: Revert "PCI: qcom: Add support for handling MSIs from 8 endpoints"

[Dmitry Baryshkov]

I have replied with my Tested-by to the patch at [2], which has landed
in the linux-next as the commit 20f1bfb8dd62 ("PCI: qcom:
Add support for handling MSIs from 8 endpoints"). However lately I
noticed that during the tests I still had 'pcie_pme=nomsi', so the
device was not forced to use higher MSI vectors.

After removing this option I noticed that high MSI vectors are not
delivered on tested platforms. Additional research pointed to
a patch in msm-4.14 ([1]), which describes that each group of MSI
vectors is mapped to the separate interrupt.

Without these changes specifying num_vectors can lead to missing MSI
interrupts and thus to devices malfunction.

[1] https://git.codelinaro.org/clo/la/kernel/msm-4.14/-/commit/671a3d5f129f4bfe477152292ada2194c8440d22
[2] https://lore.kernel.org/linux-arm-msm/20211214101319.25258-1-manivannan.sadhasivam@linaro.org/

Fixes: 20f1bfb8dd62 ("PCI: qcom: Add support for handling MSIs from 8 endpoints")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 drivers/pci/controller/dwc/pcie-qcom.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index f9a61ad6d1f0..2e5464edc36e 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1587,7 +1587,6 @@ static int qcom_pcie_probe(struct platform_device *pdev)
 	pci->dev = dev;
 	pci->ops = &dw_pcie_ops;
 	pp = &pci->pp;
-	pp->num_vectors = MAX_MSI_IRQS;
 
 	pcie->pci = pci;
 
-- 
2.35.1

[PATCH v10 02/10] PCI: dwc: Propagate error from dma_mapping_error()

[Dmitry Baryshkov]

If dma mapping fails, dma_mapping_error() will return an error.
Propagate it to the dw_pcie_host_init() return value rather than
incorrectly returning 0 in this case.

Fixes: 07940c369a6b ("PCI: dwc: Fix MSI page leakage in suspend/resume")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 2fa86f32d964..a9a31e9e7b6e 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -396,8 +396,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
 						      sizeof(pp->msi_msg),
 						      DMA_FROM_DEVICE,
 						      DMA_ATTR_SKIP_CPU_SYNC);
-			if (dma_mapping_error(pci->dev, pp->msi_data)) {
-				dev_err(pci->dev, "Failed to map MSI data\n");
+			ret = dma_mapping_error(pci->dev, pp->msi_data);
+			if (ret) {
+				dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
 				pp->msi_data = 0;
 				goto err_free_msi;
 			}
-- 
2.35.1

[PATCH v10 03/10] PCI: dwc: Correct msi_irq condition in dw_pcie_free_msi()

[Dmitry Baryshkov]

The subdrivers pass -ESOMETHING if they do not want the core to touch
MSI IRQ. dw_pcie_host_init() also checks if (msi_irq > 0) rather than
just if (msi_irq). So let's make dw_pcie_free_msi() also check that
msi_irq is greater than zero.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index a9a31e9e7b6e..1874a09fb8fb 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -257,7 +257,7 @@ int dw_pcie_allocate_domains(struct pcie_port *pp)
 
 static void dw_pcie_free_msi(struct pcie_port *pp)
 {
-	if (pp->msi_irq)
+	if (pp->msi_irq > 0)
 		irq_set_chained_handler_and_data(pp->msi_irq, NULL, NULL);
 
 	irq_domain_remove(pp->msi_domain);
-- 
2.35.1

[PATCH v10 04/10] PCI: dwc: Convert msi_irq to the array

[Dmitry Baryshkov]

Qualcomm version of DWC PCIe controller supports more than 32 MSI
interrupts, but they are routed to separate interrupts in groups of 32
vectors. To support such configuration, change the msi_irq field into an
array. Let the DWC core handle all interrupts that were set in this
array.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/pci/controller/dwc/pci-dra7xx.c       |  2 +-
 drivers/pci/controller/dwc/pci-exynos.c       |  2 +-
 .../pci/controller/dwc/pcie-designware-host.c | 30 +++++++++++--------
 drivers/pci/controller/dwc/pcie-designware.h  |  2 +-
 drivers/pci/controller/dwc/pcie-keembay.c     |  2 +-
 drivers/pci/controller/dwc/pcie-spear13xx.c   |  2 +-
 drivers/pci/controller/dwc/pcie-tegra194.c    |  2 +-
 7 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index dfcdeb432dc8..0919c96dcdbd 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -483,7 +483,7 @@ static int dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx,
 		return pp->irq;
 
 	/* MSI IRQ is muxed */
-	pp->msi_irq = -ENODEV;
+	pp->msi_irq[0] = -ENODEV;
 
 	ret = dra7xx_pcie_init_irq_domain(pp);
 	if (ret < 0)
diff --git a/drivers/pci/controller/dwc/pci-exynos.c b/drivers/pci/controller/dwc/pci-exynos.c
index 467c8d1cd7e4..4f2010bd9cd7 100644
--- a/drivers/pci/controller/dwc/pci-exynos.c
+++ b/drivers/pci/controller/dwc/pci-exynos.c
@@ -292,7 +292,7 @@ static int exynos_add_pcie_port(struct exynos_pcie *ep,
 	}
 
 	pp->ops = &exynos_pcie_host_ops;
-	pp->msi_irq = -ENODEV;
+	pp->msi_irq[0] = -ENODEV;
 
 	ret = dw_pcie_host_init(pp);
 	if (ret) {
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 1874a09fb8fb..5f6590929319 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -257,8 +257,11 @@ int dw_pcie_allocate_domains(struct pcie_port *pp)
 
 static void dw_pcie_free_msi(struct pcie_port *pp)
 {
-	if (pp->msi_irq > 0)
-		irq_set_chained_handler_and_data(pp->msi_irq, NULL, NULL);
+	u32 ctrl;
+
+	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++)
+		if (pp->msi_irq[ctrl] > 0)
+			irq_set_chained_handler_and_data(pp->msi_irq[ctrl], NULL, NULL);
 
 	irq_domain_remove(pp->msi_domain);
 	irq_domain_remove(pp->irq_domain);
@@ -368,13 +371,15 @@ int dw_pcie_host_init(struct pcie_port *pp)
 			for (ctrl = 0; ctrl < num_ctrls; ctrl++)
 				pp->irq_mask[ctrl] = ~0;
 
-			if (!pp->msi_irq) {
-				pp->msi_irq = platform_get_irq_byname_optional(pdev, "msi");
-				if (pp->msi_irq < 0) {
-					pp->msi_irq = platform_get_irq(pdev, 0);
-					if (pp->msi_irq < 0)
-						return pp->msi_irq;
+			if (!pp->msi_irq[0]) {
+				int irq = platform_get_irq_byname_optional(pdev, "msi");
+
+				if (irq < 0) {
+					irq = platform_get_irq(pdev, 0);
+					if (irq < 0)
+						return irq;
 				}
+				pp->msi_irq[0] = irq;
 			}
 
 			pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
@@ -383,10 +388,11 @@ int dw_pcie_host_init(struct pcie_port *pp)
 			if (ret)
 				return ret;
 
-			if (pp->msi_irq > 0)
-				irq_set_chained_handler_and_data(pp->msi_irq,
-							    dw_chained_msi_isr,
-							    pp);
+			for (ctrl = 0; ctrl < num_ctrls; ctrl++)
+				if (pp->msi_irq[ctrl] > 0)
+					irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
+									 dw_chained_msi_isr,
+									 pp);
 
 			ret = dma_set_mask(pci->dev, DMA_BIT_MASK(32));
 			if (ret)
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 7d6e9b7576be..9c1a38b0a6b3 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -187,7 +187,7 @@ struct pcie_port {
 	u32			io_size;
 	int			irq;
 	const struct dw_pcie_host_ops *ops;
-	int			msi_irq;
+	int			msi_irq[MAX_MSI_CTRLS];
 	struct irq_domain	*irq_domain;
 	struct irq_domain	*msi_domain;
 	u16			msi_msg;
diff --git a/drivers/pci/controller/dwc/pcie-keembay.c b/drivers/pci/controller/dwc/pcie-keembay.c
index 1ac29a6eef22..297e6e926c00 100644
--- a/drivers/pci/controller/dwc/pcie-keembay.c
+++ b/drivers/pci/controller/dwc/pcie-keembay.c
@@ -338,7 +338,7 @@ static int keembay_pcie_add_pcie_port(struct keembay_pcie *pcie,
 	int ret;
 
 	pp->ops = &keembay_pcie_host_ops;
-	pp->msi_irq = -ENODEV;
+	pp->msi_irq[0] = -ENODEV;
 
 	ret = keembay_pcie_setup_msi_irq(pcie);
 	if (ret)
diff --git a/drivers/pci/controller/dwc/pcie-spear13xx.c b/drivers/pci/controller/dwc/pcie-spear13xx.c
index 1569e82b5568..cc7776833810 100644
--- a/drivers/pci/controller/dwc/pcie-spear13xx.c
+++ b/drivers/pci/controller/dwc/pcie-spear13xx.c
@@ -172,7 +172,7 @@ static int spear13xx_add_pcie_port(struct spear13xx_pcie *spear13xx_pcie,
 	}
 
 	pp->ops = &spear13xx_pcie_host_ops;
-	pp->msi_irq = -ENODEV;
+	pp->msi_irq[0] = -ENODEV;
 
 	ret = dw_pcie_host_init(pp);
 	if (ret) {
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index b1b5f836a806..e75712db85b0 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -2271,7 +2271,7 @@ static void tegra194_pcie_shutdown(struct platform_device *pdev)
 
 	disable_irq(pcie->pci.pp.irq);
 	if (IS_ENABLED(CONFIG_PCI_MSI))
-		disable_irq(pcie->pci.pp.msi_irq);
+		disable_irq(pcie->pci.pp.msi_irq[0]);
 
 	tegra194_pcie_pme_turnoff(pcie);
 	tegra_pcie_unconfig_controller(pcie);
-- 
2.35.1

[PATCH v10 05/10] PCI: dwc: split MSI IRQ parsing/allocation to a separate function

[Dmitry Baryshkov]

Split handling of MSI host IRQs to a separate dw_pcie_msi_host_init()
function. The code is complex enough to warrant a separate function.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../pci/controller/dwc/pcie-designware-host.c | 98 +++++++++++--------
 1 file changed, 56 insertions(+), 42 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 5f6590929319..70f0435907c1 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -288,6 +288,60 @@ static void dw_pcie_msi_init(struct pcie_port *pp)
 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
 }
 
+static int dw_pcie_msi_host_init(struct pcie_port *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct device *dev = pci->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	int ret;
+	u32 ctrl, num_ctrls;
+
+	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
+	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
+		pp->irq_mask[ctrl] = ~0;
+
+	if (!pp->msi_irq[0]) {
+		int irq = platform_get_irq_byname_optional(pdev, "msi");
+
+		if (irq < 0) {
+			irq = platform_get_irq(pdev, 0);
+			if (irq < 0)
+				return irq;
+		}
+		pp->msi_irq[0] = irq;
+	}
+
+	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
+
+	ret = dw_pcie_allocate_domains(pp);
+	if (ret)
+		return ret;
+
+	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
+		if (pp->msi_irq[ctrl] > 0)
+			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
+							 dw_chained_msi_isr,
+							 pp);
+
+	ret = dma_set_mask(pci->dev, DMA_BIT_MASK(32));
+	if (ret)
+		dev_warn(pci->dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n");
+
+	pp->msi_data = dma_map_single_attrs(pci->dev, &pp->msi_msg,
+					    sizeof(pp->msi_msg),
+					    DMA_FROM_DEVICE,
+					    DMA_ATTR_SKIP_CPU_SYNC);
+	ret = dma_mapping_error(pci->dev, pp->msi_data);
+	if (ret) {
+		dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
+		pp->msi_data = 0;
+		dw_pcie_free_msi(pp);
+		return ret;
+	}
+
+	return 0;
+}
+
 int dw_pcie_host_init(struct pcie_port *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -365,49 +419,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
 			if (ret < 0)
 				return ret;
 		} else if (pp->has_msi_ctrl) {
-			u32 ctrl, num_ctrls;
-
-			num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
-			for (ctrl = 0; ctrl < num_ctrls; ctrl++)
-				pp->irq_mask[ctrl] = ~0;
-
-			if (!pp->msi_irq[0]) {
-				int irq = platform_get_irq_byname_optional(pdev, "msi");
-
-				if (irq < 0) {
-					irq = platform_get_irq(pdev, 0);
-					if (irq < 0)
-						return irq;
-				}
-				pp->msi_irq[0] = irq;
-			}
-
-			pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
-
-			ret = dw_pcie_allocate_domains(pp);
-			if (ret)
+			ret = dw_pcie_msi_host_init(pp);
+			if (ret < 0)
 				return ret;
-
-			for (ctrl = 0; ctrl < num_ctrls; ctrl++)
-				if (pp->msi_irq[ctrl] > 0)
-					irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
-									 dw_chained_msi_isr,
-									 pp);
-
-			ret = dma_set_mask(pci->dev, DMA_BIT_MASK(32));
-			if (ret)
-				dev_warn(pci->dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n");
-
-			pp->msi_data = dma_map_single_attrs(pci->dev, &pp->msi_msg,
-						      sizeof(pp->msi_msg),
-						      DMA_FROM_DEVICE,
-						      DMA_ATTR_SKIP_CPU_SYNC);
-			ret = dma_mapping_error(pci->dev, pp->msi_data);
-			if (ret) {
-				dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
-				pp->msi_data = 0;
-				goto err_free_msi;
-			}
 		}
 	}
 
-- 
2.35.1

[PATCH v10 06/10] PCI: dwc: Handle MSIs routed to multiple GIC interrupts

[Dmitry Baryshkov]

On some of Qualcomm platforms each group of 32 MSI vectors is routed to the
separate GIC interrupt. Implement support for such configurations by
parsing "msi0" ... "msiN" interrupts and attaching them to the chained
handler.

Note, that if DT doesn't list an array of MSI interrupts and uses single
"msi" IRQ, the driver will limit the amount of supported MSI vectors
accordingly (to 32).

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../pci/controller/dwc/pcie-designware-host.c | 38 ++++++++++++++++++-
 drivers/pci/controller/dwc/pcie-designware.h  |  1 +
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 70f0435907c1..320a968dd366 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -288,6 +288,11 @@ static void dw_pcie_msi_init(struct pcie_port *pp)
 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
 }
 
+static const char * const split_msi_names[] = {
+	"msi0", "msi1", "msi2", "msi3",
+	"msi4", "msi5", "msi6", "msi7",
+};
+
 static int dw_pcie_msi_host_init(struct pcie_port *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -300,17 +305,48 @@ static int dw_pcie_msi_host_init(struct pcie_port *pp)
 	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
 		pp->irq_mask[ctrl] = ~0;
 
+	if (pp->has_split_msi_irq) {
+		/*
+		 * Parse as many IRQs as described in the DTS. If there are
+		 * none, fallback to the single "msi" IRQ.
+		 */
+		for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
+			int irq;
+
+			if (pp->msi_irq[ctrl])
+				continue;
+
+			irq = platform_get_irq_byname(pdev, split_msi_names[ctrl]);
+			if (irq == -ENXIO) {
+				num_ctrls = ctrl;
+				break;
+			} else if (irq < 0) {
+				return dev_err_probe(dev, irq,
+						     "Failed to parse MSI IRQ '%s'\n",
+						     split_msi_names[ctrl]);
+			}
+
+			pp->msi_irq[ctrl] = irq;
+		}
+
+		if (num_ctrls == 0)
+			num_ctrls = 1;
+	}
+
 	if (!pp->msi_irq[0]) {
 		int irq = platform_get_irq_byname_optional(pdev, "msi");
 
 		if (irq < 0) {
 			irq = platform_get_irq(pdev, 0);
 			if (irq < 0)
-				return irq;
+				return dev_err_probe(dev, irq, "Failed to parse MSI irq\n");
 		}
 		pp->msi_irq[0] = irq;
 	}
 
+	pp->num_vectors = min_t(u32, pp->num_vectors, num_ctrls * MAX_MSI_IRQS_PER_CTRL);
+	dev_dbg(dev, "Using %d MSI vectors\n", pp->num_vectors);
+
 	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
 
 	ret = dw_pcie_allocate_domains(pp);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 9c1a38b0a6b3..3aa840a5b19c 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -179,6 +179,7 @@ struct dw_pcie_host_ops {
 
 struct pcie_port {
 	bool			has_msi_ctrl:1;
+	bool			has_split_msi_irq:1;
 	u64			cfg0_base;
 	void __iomem		*va_cfg0_base;
 	u32			cfg0_size;
-- 
2.35.1

[PATCH v10 07/10] PCI: dwc: Implement special ISR handler for split MSI IRQ setup

[Dmitry Baryshkov]

If the PCIe DWC controller uses split MSI IRQs for reporting MSI
vectors, it is possible to detect, which group triggered the interrupt.
Provide an optimized version of MSI ISR handler that will handle just a
single MSI group instead of handling all of them.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../pci/controller/dwc/pcie-designware-host.c | 83 ++++++++++++++-----
 1 file changed, 62 insertions(+), 21 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 320a968dd366..c0abf098dc78 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -52,34 +52,42 @@ static struct msi_domain_info dw_pcie_msi_domain_info = {
 	.chip	= &dw_pcie_msi_irq_chip,
 };
 
+static inline irqreturn_t dw_handle_single_msi_group(struct pcie_port *pp, int i)
+{
+	int pos;
+	unsigned long val;
+	u32 status;
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+
+	status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
+				   (i * MSI_REG_CTRL_BLOCK_SIZE));
+	if (!status)
+		return IRQ_NONE;
+
+	val = status;
+	pos = 0;
+	while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL,
+				    pos)) != MAX_MSI_IRQS_PER_CTRL) {
+		generic_handle_domain_irq(pp->irq_domain,
+					  (i * MAX_MSI_IRQS_PER_CTRL) +
+					  pos);
+		pos++;
+	}
+
+	return IRQ_HANDLED;
+}
+
 /* MSI int handler */
 irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
 {
-	int i, pos;
-	unsigned long val;
-	u32 status, num_ctrls;
+	int i;
+	u32 num_ctrls;
 	irqreturn_t ret = IRQ_NONE;
-	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
 
 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
 
-	for (i = 0; i < num_ctrls; i++) {
-		status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
-					   (i * MSI_REG_CTRL_BLOCK_SIZE));
-		if (!status)
-			continue;
-
-		ret = IRQ_HANDLED;
-		val = status;
-		pos = 0;
-		while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL,
-					    pos)) != MAX_MSI_IRQS_PER_CTRL) {
-			generic_handle_domain_irq(pp->irq_domain,
-						  (i * MAX_MSI_IRQS_PER_CTRL) +
-						  pos);
-			pos++;
-		}
-	}
+	for (i = 0; i < num_ctrls; i++)
+		ret |= dw_handle_single_msi_group(pp, i);
 
 	return ret;
 }
@@ -98,6 +106,38 @@ static void dw_chained_msi_isr(struct irq_desc *desc)
 	chained_irq_exit(chip, desc);
 }
 
+static void dw_split_msi_isr(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	int irq = irq_desc_get_irq(desc);
+	struct pcie_port *pp;
+	int i;
+	u32 num_ctrls;
+	struct dw_pcie *pci;
+
+	chained_irq_enter(chip, desc);
+
+	pp = irq_desc_get_handler_data(desc);
+	pci = to_dw_pcie_from_pp(pp);
+
+	/*
+	 * Unlike generic dw_handle_msi_irq(), we can determine which group of
+	 * MSIs triggered the IRQ, so process just that group.
+	 */
+	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
+
+	for (i = 0; i < num_ctrls; i++) {
+		if (pp->msi_irq[i] == irq) {
+			dw_handle_single_msi_group(pp, i);
+			break;
+		}
+	}
+
+	WARN_ON_ONCE(i == num_ctrls);
+
+	chained_irq_exit(chip, desc);
+}
+
 static void dw_pci_setup_msi_msg(struct irq_data *d, struct msi_msg *msg)
 {
 	struct pcie_port *pp = irq_data_get_irq_chip_data(d);
@@ -356,6 +396,7 @@ static int dw_pcie_msi_host_init(struct pcie_port *pp)
 	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
 		if (pp->msi_irq[ctrl] > 0)
 			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
+							 pp->has_split_msi_irq ? dw_split_msi_isr :
 							 dw_chained_msi_isr,
 							 pp);
 
-- 
2.35.1

[PATCH v10 08/10] PCI: qcom: Handle MSIs routed to multiple GIC interrupts

[Dmitry Baryshkov]

On some of Qualcomm platforms each group of 32 MSI vectors is routed to the
separate GIC interrupt. Thus, to receive higher MSI vectors properly,
declare that the host should use split MSI IRQ handling on these
platforms.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/pci/controller/dwc/pcie-qcom.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 2e5464edc36e..f79752d1d680 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -194,6 +194,7 @@ struct qcom_pcie_ops {
 
 struct qcom_pcie_cfg {
 	const struct qcom_pcie_ops *ops;
+	unsigned int has_split_msi_irq:1;
 	unsigned int pipe_clk_need_muxing:1;
 	unsigned int has_tbu_clk:1;
 	unsigned int has_ddrss_sf_tbu_clk:1;
@@ -1502,6 +1503,7 @@ static const struct qcom_pcie_cfg ipq8064_cfg = {
 
 static const struct qcom_pcie_cfg msm8996_cfg = {
 	.ops = &ops_2_3_2,
+	.has_split_msi_irq = true,
 };
 
 static const struct qcom_pcie_cfg ipq8074_cfg = {
@@ -1514,6 +1516,7 @@ static const struct qcom_pcie_cfg ipq4019_cfg = {
 
 static const struct qcom_pcie_cfg sdm845_cfg = {
 	.ops = &ops_2_7_0,
+	.has_split_msi_irq = true,
 	.has_tbu_clk = true,
 };
 
@@ -1526,12 +1529,14 @@ static const struct qcom_pcie_cfg sm8150_cfg = {
 
 static const struct qcom_pcie_cfg sm8250_cfg = {
 	.ops = &ops_1_9_0,
+	.has_split_msi_irq = true,
 	.has_tbu_clk = true,
 	.has_ddrss_sf_tbu_clk = true,
 };
 
 static const struct qcom_pcie_cfg sm8450_pcie0_cfg = {
 	.ops = &ops_1_9_0,
+	.has_split_msi_irq = true,
 	.has_ddrss_sf_tbu_clk = true,
 	.pipe_clk_need_muxing = true,
 	.has_aggre0_clk = true,
@@ -1540,6 +1545,7 @@ static const struct qcom_pcie_cfg sm8450_pcie0_cfg = {
 
 static const struct qcom_pcie_cfg sm8450_pcie1_cfg = {
 	.ops = &ops_1_9_0,
+	.has_split_msi_irq = true,
 	.has_ddrss_sf_tbu_clk = true,
 	.pipe_clk_need_muxing = true,
 	.has_aggre1_clk = true,
@@ -1547,6 +1553,7 @@ static const struct qcom_pcie_cfg sm8450_pcie1_cfg = {
 
 static const struct qcom_pcie_cfg sc7280_cfg = {
 	.ops = &ops_1_9_0,
+	.has_split_msi_irq = true,
 	.has_tbu_clk = true,
 	.pipe_clk_need_muxing = true,
 };
@@ -1592,6 +1599,11 @@ static int qcom_pcie_probe(struct platform_device *pdev)
 
 	pcie->cfg = pcie_cfg;
 
+	if (pcie->cfg->has_split_msi_irq) {
+		pp->num_vectors = MAX_MSI_IRQS;
+		pp->has_split_msi_irq = true;
+	}
+
 	pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
 	if (IS_ERR(pcie->reset)) {
 		ret = PTR_ERR(pcie->reset);
-- 
2.35.1

[PATCH v10 09/10] dt-bindings: PCI: qcom: Support additional MSI interrupts

[Dmitry Baryshkov]

On Qualcomm platforms each group of 32 MSI vectors is routed to the
separate GIC interrupt. Document mapping of additional interrupts.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../devicetree/bindings/pci/qcom,pcie.yaml    | 53 +++++++++++++++++--
 1 file changed, 50 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
index 0b69b12b849e..fe8f9a62a665 100644
--- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
@@ -43,11 +43,12 @@ properties:
     maxItems: 5
 
   interrupts:
-    maxItems: 1
+    minItems: 1
+    maxItems: 8
 
   interrupt-names:
-    items:
-      - const: msi
+    minItems: 1
+    maxItems: 8
 
   # Common definitions for clocks, clock-names and reset.
   # Platform constraints are described later.
@@ -623,6 +624,52 @@ allOf:
         - resets
         - reset-names
 
+    # On newer chipsets support either 1 or 8 msi interrupts
+    # On older chipsets it's always 1 msi interrupt
+  - if:
+      properties:
+        compatibles:
+          contains:
+            enum:
+              - qcom,pcie-msm8996
+              - qcom,pcie-sc7280
+              - qcom,pcie-sc8180x
+              - qcom,pcie-sdm845
+              - qcom,pcie-sm8150
+              - qcom,pcie-sm8250
+              - qcom,pcie-sm8450-pcie0
+              - qcom,pcie-sm8450-pcie1
+    then:
+      oneOf:
+        - properties:
+            interrupts:
+              maxItems: 1
+            interrupt-names:
+              maxItems: 1
+              items:
+                - const: msi
+        - properties:
+            interrupts:
+              minItems: 8
+            interrupt-names:
+              minItems: 8
+              items:
+                - const: msi0
+                - const: msi1
+                - const: msi2
+                - const: msi3
+                - const: msi4
+                - const: msi5
+                - const: msi6
+                - const: msi7
+    else:
+      properties:
+        interrupts:
+          maxItems: 1
+        interrupt-names:
+          items:
+            - const: msi
+
 unevaluatedProperties: false
 
 examples:
-- 
2.35.1

[PATCH v10 10/10] arm64: dts: qcom: sm8250: provide additional MSI interrupts

[Dmitry Baryshkov]

On SM8250 each group of MSI interrupts is mapped to the separate host
interrupt. Describe each of interrupts in the device tree for PCIe0
host.

Tested on Qualcomm RB5 platform with first group of MSI interrupts being
used by the PME and attached ath11k WiFi chip using second group of MSI
interrupts.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 arch/arm64/boot/dts/qcom/sm8250.dtsi | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sm8250.dtsi b/arch/arm64/boot/dts/qcom/sm8250.dtsi
index 410272a1e19b..523a035ffc5f 100644
--- a/arch/arm64/boot/dts/qcom/sm8250.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8250.dtsi
@@ -1807,8 +1807,16 @@ pcie0: pci@1c00000 {
 			ranges = <0x01000000 0x0 0x60200000 0 0x60200000 0x0 0x100000>,
 				 <0x02000000 0x0 0x60300000 0 0x60300000 0x0 0x3d00000>;
 
-			interrupts = <GIC_SPI 141 IRQ_TYPE_LEVEL_HIGH>;
-			interrupt-names = "msi";
+			interrupts = <GIC_SPI 141 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 142 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 143 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 145 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 146 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-names = "msi0", "msi1", "msi2", "msi3",
+					  "msi4", "msi5", "msi6", "msi7";
 			#interrupt-cells = <1>;
 			interrupt-map-mask = <0 0 0 0x7>;
 			interrupt-map = <0 0 0 1 &intc 0 149 IRQ_TYPE_LEVEL_HIGH>, /* int_a */
-- 
2.35.1

Re: [PATCH v10 02/10] PCI: dwc: Propagate error from dma_mapping_error()

[Johan Hovold]

On Fri, May 13, 2022 at 08:26:14PM +0300, Dmitry Baryshkov wrote:
> If dma mapping fails, dma_mapping_error() will return an error.
> Propagate it to the dw_pcie_host_init() return value rather than
> incorrectly returning 0 in this case.
> 
> Fixes: 07940c369a6b ("PCI: dwc: Fix MSI page leakage in suspend/resume")
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 2fa86f32d964..a9a31e9e7b6e 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -396,8 +396,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
>  						      sizeof(pp->msi_msg),
>  						      DMA_FROM_DEVICE,
>  						      DMA_ATTR_SKIP_CPU_SYNC);
> -			if (dma_mapping_error(pci->dev, pp->msi_data)) {
> -				dev_err(pci->dev, "Failed to map MSI data\n");
> +			ret = dma_mapping_error(pci->dev, pp->msi_data);
> +			if (ret) {
> +				dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
>  				pp->msi_data = 0;
>  				goto err_free_msi;
>  			}

This has already been fixed by commit 88557685cd72 ("PCI: dwc: Fix
setting error return on MSI DMA mapping failure"), which prevents the
series from applying cleanly.

Johan

Re: [PATCH v10 06/10] PCI: dwc: Handle MSIs routed to multiple GIC interrupts

[Johan Hovold]

On Fri, May 13, 2022 at 08:26:18PM +0300, Dmitry Baryshkov wrote:
> On some of Qualcomm platforms each group of 32 MSI vectors is routed to the
> separate GIC interrupt. Implement support for such configurations by
> parsing "msi0" ... "msiN" interrupts and attaching them to the chained
> handler.
> 
> Note, that if DT doesn't list an array of MSI interrupts and uses single
> "msi" IRQ, the driver will limit the amount of supported MSI vectors
> accordingly (to 32).
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  .../pci/controller/dwc/pcie-designware-host.c | 38 ++++++++++++++++++-
>  drivers/pci/controller/dwc/pcie-designware.h  |  1 +
>  2 files changed, 38 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 70f0435907c1..320a968dd366 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -288,6 +288,11 @@ static void dw_pcie_msi_init(struct pcie_port *pp)
>  	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
>  }
>  
> +static const char * const split_msi_names[] = {
> +	"msi0", "msi1", "msi2", "msi3",
> +	"msi4", "msi5", "msi6", "msi7",
> +};
> +
>  static int dw_pcie_msi_host_init(struct pcie_port *pp)
>  {
>  	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> @@ -300,17 +305,48 @@ static int dw_pcie_msi_host_init(struct pcie_port *pp)
>  	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
>  		pp->irq_mask[ctrl] = ~0;
>  
> +	if (pp->has_split_msi_irq) {

You don't need to add this configuration parameter as it can be inferred
from the devicetree (e.g. if "msi0" is specified).

> +		/*
> +		 * Parse as many IRQs as described in the DTS. If there are
> +		 * none, fallback to the single "msi" IRQ.
> +		 */
> +		for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
> +			int irq;
> +
> +			if (pp->msi_irq[ctrl])
> +				continue;
> +
> +			irq = platform_get_irq_byname(pdev, split_msi_names[ctrl]);

You need to use platform_get_irq_byname_optional() here or an error will
still printed if the number of "msi" interrupts is less than 8.

> +			if (irq == -ENXIO) {
> +				num_ctrls = ctrl;
> +				break;
> +			} else if (irq < 0) {
> +				return dev_err_probe(dev, irq,
> +						     "Failed to parse MSI IRQ '%s'\n",
> +						     split_msi_names[ctrl]);
> +			}
> +
> +			pp->msi_irq[ctrl] = irq;
> +		}
> +
> +		if (num_ctrls == 0)
> +			num_ctrls = 1;
> +	}
> +
>  	if (!pp->msi_irq[0]) {
>  		int irq = platform_get_irq_byname_optional(pdev, "msi");
>  
>  		if (irq < 0) {
>  			irq = platform_get_irq(pdev, 0);
>  			if (irq < 0)
> -				return irq;
> +				return dev_err_probe(dev, irq, "Failed to parse MSI irq\n");
>  		}
>  		pp->msi_irq[0] = irq;
>  	}
>  
> +	pp->num_vectors = min_t(u32, pp->num_vectors, num_ctrls * MAX_MSI_IRQS_PER_CTRL);
> +	dev_dbg(dev, "Using %d MSI vectors\n", pp->num_vectors);

Can you rework the handling of num_vectors == 0 (in dw_pcie_host_init())
so that the number is always inferred from the number of "msi"
interrupts without having to pass in num_vectors == MAX_MSI_IRQS?

That is

	num_vectors == 0 && "msi" => num_vectors = MSI_DEF_NUM_VECTORS (32)
	num_vectors == 0 && "msi0".."msin" => num_vectors = n * MAX_MSI_IRQS_PER_CTRL (n * 32)

> +
>  	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
>  
>  	ret = dw_pcie_allocate_domains(pp);
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 9c1a38b0a6b3..3aa840a5b19c 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -179,6 +179,7 @@ struct dw_pcie_host_ops {
>  
>  struct pcie_port {
>  	bool			has_msi_ctrl:1;
> +	bool			has_split_msi_irq:1;
>  	u64			cfg0_base;
>  	void __iomem		*va_cfg0_base;
>  	u32			cfg0_size;

Johan

Re: [PATCH v10 08/10] PCI: qcom: Handle MSIs routed to multiple GIC interrupts

[Johan Hovold]

On Fri, May 13, 2022 at 08:26:20PM +0300, Dmitry Baryshkov wrote:
> On some of Qualcomm platforms each group of 32 MSI vectors is routed to the
> separate GIC interrupt. Thus, to receive higher MSI vectors properly,
> declare that the host should use split MSI IRQ handling on these
> platforms.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 2e5464edc36e..f79752d1d680 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -194,6 +194,7 @@ struct qcom_pcie_ops {
>  
>  struct qcom_pcie_cfg {
>  	const struct qcom_pcie_ops *ops;
> +	unsigned int has_split_msi_irq:1;
>  	unsigned int pipe_clk_need_muxing:1;
>  	unsigned int has_tbu_clk:1;
>  	unsigned int has_ddrss_sf_tbu_clk:1;
> @@ -1502,6 +1503,7 @@ static const struct qcom_pcie_cfg ipq8064_cfg = {
>  
>  static const struct qcom_pcie_cfg msm8996_cfg = {
>  	.ops = &ops_2_3_2,
> +	.has_split_msi_irq = true,
>  };

> @@ -1592,6 +1599,11 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  
>  	pcie->cfg = pcie_cfg;
>  
> +	if (pcie->cfg->has_split_msi_irq) {
> +		pp->num_vectors = MAX_MSI_IRQS;
> +		pp->has_split_msi_irq = true;
> +	}
> +
>  	pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
>  	if (IS_ERR(pcie->reset)) {
>  		ret = PTR_ERR(pcie->reset);

So if you fix dwc core to always infer num_vectors when passed in as 0
as I just suggested, then this patch isn't needed.

It also avoids having to pass in MAX_MSI_IRQS (or complicate the qcom
driver) for sc8280xp which only uses four "msi" GIC interrupts and hence
only MAX_MSI_IRQS/2 vectors.

Johan

Re: [PATCH v10 10/10] arm64: dts: qcom: sm8250: provide additional MSI interrupts

[Johan Hovold]

On Fri, May 13, 2022 at 08:26:22PM +0300, Dmitry Baryshkov wrote:
> On SM8250 each group of MSI interrupts is mapped to the separate host
> interrupt. Describe each of interrupts in the device tree for PCIe0
> host.
> 
> Tested on Qualcomm RB5 platform with first group of MSI interrupts being
> used by the PME and attached ath11k WiFi chip using second group of MSI
> interrupts.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  arch/arm64/boot/dts/qcom/sm8250.dtsi | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8250.dtsi b/arch/arm64/boot/dts/qcom/sm8250.dtsi
> index 410272a1e19b..523a035ffc5f 100644
> --- a/arch/arm64/boot/dts/qcom/sm8250.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8250.dtsi
> @@ -1807,8 +1807,16 @@ pcie0: pci@1c00000 {
>  			ranges = <0x01000000 0x0 0x60200000 0 0x60200000 0x0 0x100000>,
>  				 <0x02000000 0x0 0x60300000 0 0x60300000 0x0 0x3d00000>;
>  
> -			interrupts = <GIC_SPI 141 IRQ_TYPE_LEVEL_HIGH>;
> -			interrupt-names = "msi";
> +			interrupts = <GIC_SPI 141 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 142 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 143 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 145 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 146 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>,
> +				     <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>;
> +			interrupt-names = "msi0", "msi1", "msi2", "msi3",
> +					  "msi4", "msi5", "msi6", "msi7";
>  			#interrupt-cells = <1>;
>  			interrupt-map-mask = <0 0 0 0x7>;
>  			interrupt-map = <0 0 0 1 &intc 0 149 IRQ_TYPE_LEVEL_HIGH>, /* int_a */

Looks correct now:

Reviewed-by: Johan Hovold <johan+linaro@kernel.org>

Re: [PATCH v10 02/10] PCI: dwc: Propagate error from dma_mapping_error()

[Dmitry Baryshkov]

On 18/05/2022 12:30, Johan Hovold wrote:
> On Fri, May 13, 2022 at 08:26:14PM +0300, Dmitry Baryshkov wrote:
>> If dma mapping fails, dma_mapping_error() will return an error.
>> Propagate it to the dw_pcie_host_init() return value rather than
>> incorrectly returning 0 in this case.
>>
>> Fixes: 07940c369a6b ("PCI: dwc: Fix MSI page leakage in suspend/resume")
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> ---
>>   drivers/pci/controller/dwc/pcie-designware-host.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
>> index 2fa86f32d964..a9a31e9e7b6e 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
>> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
>> @@ -396,8 +396,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
>>   						      sizeof(pp->msi_msg),
>>   						      DMA_FROM_DEVICE,
>>   						      DMA_ATTR_SKIP_CPU_SYNC);
>> -			if (dma_mapping_error(pci->dev, pp->msi_data)) {
>> -				dev_err(pci->dev, "Failed to map MSI data\n");
>> +			ret = dma_mapping_error(pci->dev, pp->msi_data);
>> +			if (ret) {
>> +				dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
>>   				pp->msi_data = 0;
>>   				goto err_free_msi;
>>   			}
> 
> This has already been fixed by commit 88557685cd72 ("PCI: dwc: Fix
> setting error return on MSI DMA mapping failure"), which prevents the
> series from applying cleanly.

Ack, will rebase and send.

> 
> Johan


-- 
With best wishes
Dmitry

Re: [PATCH v10 06/10] PCI: dwc: Handle MSIs routed to multiple GIC interrupts

[Dmitry Baryshkov]

On 18/05/2022 12:43, Johan Hovold wrote:
> On Fri, May 13, 2022 at 08:26:18PM +0300, Dmitry Baryshkov wrote:
>> On some of Qualcomm platforms each group of 32 MSI vectors is routed to the
>> separate GIC interrupt. Implement support for such configurations by
>> parsing "msi0" ... "msiN" interrupts and attaching them to the chained
>> handler.
>>
>> Note, that if DT doesn't list an array of MSI interrupts and uses single
>> "msi" IRQ, the driver will limit the amount of supported MSI vectors
>> accordingly (to 32).
>>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> ---
>>   .../pci/controller/dwc/pcie-designware-host.c | 38 ++++++++++++++++++-
>>   drivers/pci/controller/dwc/pcie-designware.h  |  1 +
>>   2 files changed, 38 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
>> index 70f0435907c1..320a968dd366 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
>> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
>> @@ -288,6 +288,11 @@ static void dw_pcie_msi_init(struct pcie_port *pp)
>>   	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
>>   }
>>   
>> +static const char * const split_msi_names[] = {
>> +	"msi0", "msi1", "msi2", "msi3",
>> +	"msi4", "msi5", "msi6", "msi7",
>> +};
>> +
>>   static int dw_pcie_msi_host_init(struct pcie_port *pp)
>>   {
>>   	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>> @@ -300,17 +305,48 @@ static int dw_pcie_msi_host_init(struct pcie_port *pp)
>>   	for (ctrl = 0; ctrl < num_ctrls; ctrl++)
>>   		pp->irq_mask[ctrl] = ~0;
>>   
>> +	if (pp->has_split_msi_irq) {
> 
> You don't need to add this configuration parameter as it can be inferred
> from the devicetree (e.g. if "msi0" is specified).
> 
>> +		/*
>> +		 * Parse as many IRQs as described in the DTS. If there are
>> +		 * none, fallback to the single "msi" IRQ.
>> +		 */
>> +		for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
>> +			int irq;
>> +
>> +			if (pp->msi_irq[ctrl])
>> +				continue;
>> +
>> +			irq = platform_get_irq_byname(pdev, split_msi_names[ctrl]);
> 
> You need to use platform_get_irq_byname_optional() here or an error will
> still printed if the number of "msi" interrupts is less than 8.
> 
>> +			if (irq == -ENXIO) {
>> +				num_ctrls = ctrl;
>> +				break;
>> +			} else if (irq < 0) {
>> +				return dev_err_probe(dev, irq,
>> +						     "Failed to parse MSI IRQ '%s'\n",
>> +						     split_msi_names[ctrl]);
>> +			}
>> +
>> +			pp->msi_irq[ctrl] = irq;
>> +		}
>> +
>> +		if (num_ctrls == 0)
>> +			num_ctrls = 1;
>> +	}
>> +
>>   	if (!pp->msi_irq[0]) {
>>   		int irq = platform_get_irq_byname_optional(pdev, "msi");
>>   
>>   		if (irq < 0) {
>>   			irq = platform_get_irq(pdev, 0);
>>   			if (irq < 0)
>> -				return irq;
>> +				return dev_err_probe(dev, irq, "Failed to parse MSI irq\n");
>>   		}
>>   		pp->msi_irq[0] = irq;
>>   	}
>>   
>> +	pp->num_vectors = min_t(u32, pp->num_vectors, num_ctrls * MAX_MSI_IRQS_PER_CTRL);
>> +	dev_dbg(dev, "Using %d MSI vectors\n", pp->num_vectors);
> 
> Can you rework the handling of num_vectors == 0 (in dw_pcie_host_init())
> so that the number is always inferred from the number of "msi"
> interrupts without having to pass in num_vectors == MAX_MSI_IRQS?

It wasn't that easy, but I think I ended up doing it properly.

> 
> That is
> 
> 	num_vectors == 0 && "msi" => num_vectors = MSI_DEF_NUM_VECTORS (32)
> 	num_vectors == 0 && "msi0".."msin" => num_vectors = n * MAX_MSI_IRQS_PER_CTRL (n * 32)
> 
>> +
>>   	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
>>   
>>   	ret = dw_pcie_allocate_domains(pp);
>> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
>> index 9c1a38b0a6b3..3aa840a5b19c 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware.h
>> +++ b/drivers/pci/controller/dwc/pcie-designware.h
>> @@ -179,6 +179,7 @@ struct dw_pcie_host_ops {
>>   
>>   struct pcie_port {
>>   	bool			has_msi_ctrl:1;
>> +	bool			has_split_msi_irq:1;
>>   	u64			cfg0_base;
>>   	void __iomem		*va_cfg0_base;
>>   	u32			cfg0_size;
> 
> Johan


-- 
With best wishes
Dmitry

Re: [PATCH v10 02/10] PCI: dwc: Propagate error from dma_mapping_error()

[Rob Herring]

On Fri, May 13, 2022 at 08:26:14PM +0300, Dmitry Baryshkov wrote:
> If dma mapping fails, dma_mapping_error() will return an error.
> Propagate it to the dw_pcie_host_init() return value rather than
> incorrectly returning 0 in this case.
> 
> Fixes: 07940c369a6b ("PCI: dwc: Fix MSI page leakage in suspend/resume")
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

There's already a similar fix applied.

> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index 2fa86f32d964..a9a31e9e7b6e 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -396,8 +396,9 @@ int dw_pcie_host_init(struct pcie_port *pp)
>  						      sizeof(pp->msi_msg),
>  						      DMA_FROM_DEVICE,
>  						      DMA_ATTR_SKIP_CPU_SYNC);
> -			if (dma_mapping_error(pci->dev, pp->msi_data)) {
> -				dev_err(pci->dev, "Failed to map MSI data\n");
> +			ret = dma_mapping_error(pci->dev, pp->msi_data);
> +			if (ret) {
> +				dev_err(pci->dev, "Failed to map MSI data: %d\n", ret);
>  				pp->msi_data = 0;
>  				goto err_free_msi;
>  			}
> -- 
> 2.35.1
>