Re: [PATCH v2 2/8] PCI: qcom: Disable write access to read only registers for IP v2.9.0
From: Dmitry Baryshkov
Date: Mon May 22 2023 - 09:01:11 EST
On Fri, 19 May 2023 at 17:31, Manivannan Sadhasivam
<manivannan.sadhasivam@xxxxxxxxxx> wrote:
>
> In the post init sequence of v2.9.0, write access to read only registers
> are not disabled after updating the registers. Fix it by disabling the
> access after register update.
>
> Fixes: 0cf7c2efe8ac ("PCI: qcom: Add IPQ60xx support")
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxx>
Could you please drop the @gmail R-B tags? I was mistaken when sending
them (I'm not even sure that this email exists).
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
> drivers/pci/controller/dwc/pcie-qcom.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 01795ee7ce45..391a45d1e70a 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -1136,6 +1136,7 @@ static int qcom_pcie_post_init_2_9_0(struct qcom_pcie *pcie)
> writel(0, pcie->parf + PARF_Q2A_FLUSH);
>
> dw_pcie_dbi_ro_wr_en(pci);
> +
> writel(PCIE_CAP_SLOT_VAL, pci->dbi_base + offset + PCI_EXP_SLTCAP);
>
> val = readl(pci->dbi_base + offset + PCI_EXP_LNKCAP);
> @@ -1145,6 +1146,8 @@ static int qcom_pcie_post_init_2_9_0(struct qcom_pcie *pcie)
> writel(PCI_EXP_DEVCTL2_COMP_TMOUT_DIS, pci->dbi_base + offset +
> PCI_EXP_DEVCTL2);
>
> + dw_pcie_dbi_ro_wr_dis(pci);
> +
> for (i = 0; i < 256; i++)
> writel(0, pcie->parf + PARF_BDF_TO_SID_TABLE_N + (4 * i));
>
> --
> 2.25.1
>
--
With best wishes
Dmitry