Re: [PATCH v2 2/8] PCI: qcom: Disable write access to read only registers for IP v2.9.0

[Manivannan Sadhasivam <mani@kernel.org>]

On Mon, May 22, 2023 at 04:00:51PM +0300, Dmitry Baryshkov wrote:
> On Fri, 19 May 2023 at 17:31, Manivannan Sadhasivam
> <manivannan.sadhasivam@linaro.org> 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@linaro.org>
> > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@gmail.com>
> 
> Could you please drop the @gmail R-B tags? I was mistaken when sending
> them (I'm not even sure that this email exists).
> 

b4 picked them up. Will drop this tag from all patches.

- Mani

> > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > ---
> >  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

-- 
மணிவண்ணன் சதாசிவம்