Re: [PATCH v3 3/3] PCI: imx6: Add code to support i.MX7D

[Andrey Smirnov]

On Mon, Feb 6, 2017 at 7:33 AM, Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote:
> Am Montag, den 06.02.2017, 07:17 -0800 schrieb Andrey Smirnov:
>> Add various bits of code needed to support i.MX7D variant of the IP.
>>
>> Cc: yurovsky@xxxxxxxxx
>> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
>> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>> Cc: Fabio Estevam <fabio.estevam@xxxxxxx>
>> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
>> Cc: Mark Rutland <mark.rutland@xxxxxxx>
>> Cc: Lee Jones <lee.jones@xxxxxxxxxx>
>> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>> Cc: devicetree@xxxxxxxxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
>
> Two small comments inline, otherwise looks real good now.
>
>> ---
>>  .../devicetree/bindings/pci/fsl,imx6q-pcie.txt     |   6 +-
>>  drivers/pci/host/pci-imx6.c                        | 121 ++++++++++++++++-----
>>  include/linux/mfd/syscon/imx7-iomuxc-gpr.h         |   4 +
>>  3 files changed, 105 insertions(+), 26 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
>> index 83aeb1f..9f57759 100644
>> --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
>> +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
>> @@ -4,7 +4,11 @@ This PCIe host controller is based on the Synopsis Designware PCIe IP
>>  and thus inherits all the common properties defined in designware-pcie.txt.
>>
>>  Required properties:
>> -- compatible: "fsl,imx6q-pcie", "fsl,imx6sx-pcie", "fsl,imx6qp-pcie"
>> +- compatible:
>> +     - "fsl,imx6q-pcie"
>> +     - "fsl,imx6sx-pcie",
>> +     - "fsl,imx6qp-pcie"
>> +     - "fsl,imx7d-pcie"
>>  - reg: base address and length of the PCIe controller
>>  - interrupts: A list of interrupt outputs of the controller. Must contain an
>>    entry for each entry in the interrupt-names property.
>
> This misses an "Additional required properties for imx7d-pcie" section
> listing the required reset handles.

Darn! Forgot to update this part. Will fix in v4.

>
>> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
>> index 3ef8093..34a21c9 100644
>> --- a/drivers/pci/host/pci-imx6.c
>> +++ b/drivers/pci/host/pci-imx6.c
>
> [...]
>
>>  static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
>>  {
>>       struct pcie_port *pp = &imx6_pcie->pp;
>> @@ -381,6 +416,11 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
>>       }
>>
>>       switch (imx6_pcie->variant) {
>> +     case IMX7D:
>> +             reset_control_assert(imx6_pcie->apps_reset);
>
> Can this reset assertion be moved into imx6_pcie_assert_core_reset()?
> This may change the programming order slightly from the downstream
> driver, but I guess that won't hurt if this is the equivalent of the
> LTSSM enable signal.

I don't see why it wouldn't be possible to move it. I'll give it a try
on a real HW and update v4 accordingly.

Thanks,
Andrey Smirnov