[PATCH v3 0/2] PCI: mediatek-gen3: Set PBUS_CSR regs for Airoha EN7581 SoC.

[PATCH v3 0/2] PCI: mediatek-gen3: Set PBUS_CSR regs for Airoha EN7581 SoC.

[Lorenzo Bianconi]

Configure PBus base address and base address mask to allow the hw
to detect if a given address is accessible on the PCIe controller.
Introduce mediatek,pbus-csr phandle array property.

Changes in v3:
- Get base address and base address mask from range property
- Define mediatek,pbus-csr as phandle array
- Link to v2: https://lore.kernel.org/r/20250202-en7581-pcie-pbus-csr-v2-0-65dcb201c9a9@kernel.org

Changes in v2:
- Introduce mediatek,pbus-csr phandle property
- Drop patch 1/2 in v1
- Do not hard-code compatible sting in the driver and use phandle
  instead

---
Lorenzo Bianconi (2):
      dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property
      PCI: mediatek-gen3: Configure PBUS_CSR registers for EN7581 SoC

 .../bindings/pci/mediatek-pcie-gen3.yaml           | 17 +++++++++++
 drivers/pci/controller/pcie-mediatek-gen3.c        | 34 +++++++++++++++++++++-
 2 files changed, 50 insertions(+), 1 deletion(-)
---
base-commit: b6d7bb0d3bd74b491e2e6fd59c4d5110d06fd63b
change-id: 20250201-en7581-pcie-pbus-csr-f9c4f88ce5b3

Best regards,
-- 
Lorenzo Bianconi <lorenzo@kernel.org>

[PATCH v3 1/2] dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property

[Lorenzo Bianconi]

Introduce the mediatek,pbus-csr property for the pbus-csr syscon node
available on EN7581 SoC. The airoha pbus-csr block provides a configuration
interface for the PBUS controller used to detect if a given address is
accessible on PCIe controller.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 .../devicetree/bindings/pci/mediatek-pcie-gen3.yaml     | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
index f05aab2b1addcac91d4685d7d94f421814822b92..162406e0691a81044406aa8f9e60605d0d917811 100644
--- a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
+++ b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
@@ -109,6 +109,17 @@ properties:
   power-domains:
     maxItems: 1
 
+  mediatek,pbus-csr:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    items:
+      - items:
+          - description: phandle to pbus-csr syscon
+          - description: offset of pbus-csr base address register
+          - description: offset of pbus-csr base address mask register
+    description:
+      Phandle with two arguments to the syscon node used to detect if
+      a given address is accessible on PCIe controller.
+
   '#interrupt-cells':
     const: 1
 
@@ -168,6 +179,8 @@ allOf:
           minItems: 1
           maxItems: 2
 
+        mediatek,pbus-csr: false
+
   - if:
       properties:
         compatible:
@@ -197,6 +210,8 @@ allOf:
           minItems: 1
           maxItems: 2
 
+        mediatek,pbus-csr: false
+
   - if:
       properties:
         compatible:
@@ -224,6 +239,8 @@ allOf:
           minItems: 1
           maxItems: 2
 
+        mediatek,pbus-csr: false
+
   - if:
       properties:
         compatible:

-- 
2.48.1

[PATCH v3 2/2] PCI: mediatek-gen3: Configure PBUS_CSR registers for EN7581 SoC

[Lorenzo Bianconi]

Configure PBus base address and address mask to allow the hw
to detect if a given address is accessible on PCIe controller.

Fixes: f6ab898356dd ("PCI: mediatek-gen3: Add Airoha EN7581 support")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 drivers/pci/controller/pcie-mediatek-gen3.c | 34 ++++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index 0f64e76e2111468e6a453889ead7fbc75804faf7..51103b7624c09ca957c22a25536dc9da25428e48 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -15,6 +15,7 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/msi.h>
 #include <linux/of_device.h>
@@ -24,6 +25,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
+#include <linux/regmap.h>
 #include <linux/reset.h>
 
 #include "../pci.h"
@@ -930,9 +932,13 @@ static int mtk_pcie_parse_port(struct mtk_gen3_pcie *pcie)
 
 static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
 {
+	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
 	struct device *dev = pcie->dev;
+	struct resource_entry *entry;
+	u32 val, args[2], size, mask;
+	struct regmap *pbus_regmap;
+	resource_size_t addr;
 	int err;
-	u32 val;
 
 	/*
 	 * The controller may have been left out of reset by the bootloader
@@ -944,6 +950,32 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
 	/* Wait for the time needed to complete the reset lines assert. */
 	msleep(PCIE_EN7581_RESET_TIME_MS);
 
+	/*
+	 * Configure PBus base address and base address mask to allow the
+	 * hw to detect if a given address is accessible on PCIe controller.
+	 */
+	pbus_regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node,
+							   "mediatek,pbus-csr",
+							   ARRAY_SIZE(args),
+							   args);
+	if (IS_ERR(pbus_regmap))
+		return PTR_ERR(pbus_regmap);
+
+	entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
+	if (!entry)
+		return -EINVAL;
+
+	addr = entry->res->start - entry->offset;
+	err = regmap_write(pbus_regmap, args[0], lower_32_bits(addr));
+	if (err)
+		return err;
+
+	size = lower_32_bits(resource_size(entry->res));
+	mask = size ? GENMASK(31, __fls(size)) : 0;
+	err = regmap_write(pbus_regmap, args[1], mask);
+	if (err)
+		return err;
+
 	/*
 	 * Unlike the other MediaTek Gen3 controllers, the Airoha EN7581
 	 * requires PHY initialization and power-on before PHY reset deassert.

-- 
2.48.1

Re: [PATCH v3 1/2] dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property

[Krzysztof Kozlowski]

On Sat, Feb 22, 2025 at 11:43:44AM +0100, Lorenzo Bianconi wrote:
> Introduce the mediatek,pbus-csr property for the pbus-csr syscon node
> available on EN7581 SoC. The airoha pbus-csr block provides a configuration
> interface for the PBUS controller used to detect if a given address is
> accessible on PCIe controller.
> 
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> ---
>  .../devicetree/bindings/pci/mediatek-pcie-gen3.yaml     | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 

You got review tag, so if you decided to skip it, this should be
mentioned why.


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH v3 1/2] dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property

[Lorenzo Bianconi]

[-- Attachment #1: Type: text/plain, Size: 931 bytes --]

> On Sat, Feb 22, 2025 at 11:43:44AM +0100, Lorenzo Bianconi wrote:
> > Introduce the mediatek,pbus-csr property for the pbus-csr syscon node
> > available on EN7581 SoC. The airoha pbus-csr block provides a configuration
> > interface for the PBUS controller used to detect if a given address is
> > accessible on PCIe controller.
> > 
> > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> > ---
> >  .../devicetree/bindings/pci/mediatek-pcie-gen3.yaml     | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> > 
> 
> You got review tag, so if you decided to skip it, this should be
> mentioned why.
> 
> 
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Since I modified the patch with respect to the previous version, I was thinking
you want to review it again before applying the Reviewed-by tag. Added it now.

Regards,
Lorenzo

> 
> Best regards,
> Krzysztof
> 

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Re: [PATCH v3 1/2] dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property

[Manivannan Sadhasivam]

On Sat, Feb 22, 2025 at 11:43:44AM +0100, Lorenzo Bianconi wrote:
> Introduce the mediatek,pbus-csr property for the pbus-csr syscon node
> available on EN7581 SoC. The airoha pbus-csr block provides a configuration
> interface for the PBUS controller used to detect if a given address is
> accessible on PCIe controller.
> 
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

- Mani

> ---
>  .../devicetree/bindings/pci/mediatek-pcie-gen3.yaml     | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
> index f05aab2b1addcac91d4685d7d94f421814822b92..162406e0691a81044406aa8f9e60605d0d917811 100644
> --- a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
> +++ b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml
> @@ -109,6 +109,17 @@ properties:
>    power-domains:
>      maxItems: 1
>  
> +  mediatek,pbus-csr:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    items:
> +      - items:
> +          - description: phandle to pbus-csr syscon
> +          - description: offset of pbus-csr base address register
> +          - description: offset of pbus-csr base address mask register
> +    description:
> +      Phandle with two arguments to the syscon node used to detect if
> +      a given address is accessible on PCIe controller.
> +
>    '#interrupt-cells':
>      const: 1
>  
> @@ -168,6 +179,8 @@ allOf:
>            minItems: 1
>            maxItems: 2
>  
> +        mediatek,pbus-csr: false
> +
>    - if:
>        properties:
>          compatible:
> @@ -197,6 +210,8 @@ allOf:
>            minItems: 1
>            maxItems: 2
>  
> +        mediatek,pbus-csr: false
> +
>    - if:
>        properties:
>          compatible:
> @@ -224,6 +239,8 @@ allOf:
>            minItems: 1
>            maxItems: 2
>  
> +        mediatek,pbus-csr: false
> +
>    - if:
>        properties:
>          compatible:
> 
> -- 
> 2.48.1
> 

-- 
மணிவண்ணன் சதாசிவம்

Re: [PATCH v3 2/2] PCI: mediatek-gen3: Configure PBUS_CSR registers for EN7581 SoC

[Manivannan Sadhasivam]

On Sat, Feb 22, 2025 at 11:43:45AM +0100, Lorenzo Bianconi wrote:
> Configure PBus base address and address mask to allow the hw
> to detect if a given address is accessible on PCIe controller.
> 
> Fixes: f6ab898356dd ("PCI: mediatek-gen3: Add Airoha EN7581 support")
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
> ---
>  drivers/pci/controller/pcie-mediatek-gen3.c | 34 ++++++++++++++++++++++++++++-
>  1 file changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
> index 0f64e76e2111468e6a453889ead7fbc75804faf7..51103b7624c09ca957c22a25536dc9da25428e48 100644
> --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> @@ -15,6 +15,7 @@
>  #include <linux/irqchip/chained_irq.h>
>  #include <linux/irqdomain.h>
>  #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
>  #include <linux/module.h>
>  #include <linux/msi.h>
>  #include <linux/of_device.h>
> @@ -24,6 +25,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
>  #include <linux/reset.h>
>  
>  #include "../pci.h"
> @@ -930,9 +932,13 @@ static int mtk_pcie_parse_port(struct mtk_gen3_pcie *pcie)
>  
>  static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
>  {
> +	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
>  	struct device *dev = pcie->dev;
> +	struct resource_entry *entry;
> +	u32 val, args[2], size, mask;
> +	struct regmap *pbus_regmap;
> +	resource_size_t addr;
>  	int err;
> -	u32 val;
>  
>  	/*
>  	 * The controller may have been left out of reset by the bootloader
> @@ -944,6 +950,32 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
>  	/* Wait for the time needed to complete the reset lines assert. */
>  	msleep(PCIE_EN7581_RESET_TIME_MS);
>  
> +	/*
> +	 * Configure PBus base address and base address mask to allow the
> +	 * hw to detect if a given address is accessible on PCIe controller.
> +	 */
> +	pbus_regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node,
> +							   "mediatek,pbus-csr",
> +							   ARRAY_SIZE(args),
> +							   args);
> +	if (IS_ERR(pbus_regmap))
> +		return PTR_ERR(pbus_regmap);
> +
> +	entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
> +	if (!entry)
> +		return -EINVAL;

-ENODEV or -ENOMEM

> +
> +	addr = entry->res->start - entry->offset;
> +	err = regmap_write(pbus_regmap, args[0], lower_32_bits(addr));
> +	if (err)

MMIO write is not supposed to fail.

> +		return err;
> +
> +	size = lower_32_bits(resource_size(entry->res));
> +	mask = size ? GENMASK(31, __fls(size)) : 0;

Size of MEM region could be 0?

> +	err = regmap_write(pbus_regmap, args[1], mask);
> +	if (err)

MMIO write is not supposed to fail.

- Mani

-- 
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Re: [PATCH v3 1/2] dt-bindings: PCI: mediatek-gen3: Add mediatek,pbus-csr phandle array property

[Krzysztof Kozlowski]

On 23/02/2025 14:39, Lorenzo Bianconi wrote:
>> On Sat, Feb 22, 2025 at 11:43:44AM +0100, Lorenzo Bianconi wrote:
>>> Introduce the mediatek,pbus-csr property for the pbus-csr syscon node
>>> available on EN7581 SoC. The airoha pbus-csr block provides a configuration
>>> interface for the PBUS controller used to detect if a given address is
>>> accessible on PCIe controller.
>>>
>>> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
>>> ---
>>>  .../devicetree/bindings/pci/mediatek-pcie-gen3.yaml     | 17 +++++++++++++++++
>>>  1 file changed, 17 insertions(+)
>>>
>>
>> You got review tag, so if you decided to skip it, this should be
>> mentioned why.
>>
>>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> 
> Since I modified the patch with respect to the previous version, I was thinking

I know

> you want to review it again before applying the Reviewed-by tag. Added it now.
That was not my comment. I commented that you must explicitly say that
you dropped someone's tag.

And docs clearly ask for that:

"Usually removal of someone's Tested-by or Reviewed-by tags should be
mentioned in the patch changelog (after the '---' separator)."

Best regards,
Krzysztof

Re: [PATCH v3 2/2] PCI: mediatek-gen3: Configure PBUS_CSR registers for EN7581 SoC

[Lorenzo Bianconi]

[-- Attachment #1: Type: text/plain, Size: 1158 bytes --]

> On Sat, Feb 22, 2025 at 11:43:45AM +0100, Lorenzo Bianconi wrote:

[...]

> > +
> > +	entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
> > +	if (!entry)
> > +		return -EINVAL;
> 
> -ENODEV or -ENOMEM

ack, I will fix it in v4

> 
> > +
> > +	addr = entry->res->start - entry->offset;
> > +	err = regmap_write(pbus_regmap, args[0], lower_32_bits(addr));
> > +	if (err)
> 
> MMIO write is not supposed to fail.

ack, I will fix it in v4

> 
> > +		return err;
> > +
> > +	size = lower_32_bits(resource_size(entry->res));
> > +	mask = size ? GENMASK(31, __fls(size)) : 0;
> 
> Size of MEM region could be 0?

I added this check since we consider just lower_32_bits().
Do you think we should remove it?

> 
> > +	err = regmap_write(pbus_regmap, args[1], mask);
> > +	if (err)
> 
> MMIO write is not supposed to fail.

ack, I will fix it in v4

BTW I will remove your Reviwed-by tag since the patch has changed
with respect to the one you added it. Please let me know if you
prepfer to keep it.

Regards,
Lorenzo

> 
> - Mani
> 
> -- 
> மணிவண்ணன் சதாசிவம்

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Re: [PATCH v3 2/2] PCI: mediatek-gen3: Configure PBUS_CSR registers for EN7581 SoC

[Manivannan Sadhasivam]

On Mon, Feb 24, 2025 at 11:05:24AM +0100, Lorenzo Bianconi wrote:
> > On Sat, Feb 22, 2025 at 11:43:45AM +0100, Lorenzo Bianconi wrote:
> 
> [...]
> 
> > > +
> > > +	entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
> > > +	if (!entry)
> > > +		return -EINVAL;
> > 
> > -ENODEV or -ENOMEM
> 
> ack, I will fix it in v4
> 
> > 
> > > +
> > > +	addr = entry->res->start - entry->offset;
> > > +	err = regmap_write(pbus_regmap, args[0], lower_32_bits(addr));
> > > +	if (err)
> > 
> > MMIO write is not supposed to fail.
> 
> ack, I will fix it in v4
> 
> > 
> > > +		return err;
> > > +
> > > +	size = lower_32_bits(resource_size(entry->res));
> > > +	mask = size ? GENMASK(31, __fls(size)) : 0;
> > 
> > Size of MEM region could be 0?
> 
> I added this check since we consider just lower_32_bits().
> Do you think we should remove it?
> 

Yes please.

> > 
> > > +	err = regmap_write(pbus_regmap, args[1], mask);
> > > +	if (err)
> > 
> > MMIO write is not supposed to fail.
> 
> ack, I will fix it in v4
> 
> BTW I will remove your Reviwed-by tag since the patch has changed
> with respect to the one you added it. Please let me know if you
> prepfer to keep it.
> 

Sure, fine with me.

- Mani

-- 
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