Re: [PATCH] PCI: tegra194: Remove unnecessary MSI enable reg save and restore

[Vidya Sagar]

On 4/8/2022 5:26 PM, Lorenzo Pieralisi wrote:
> External email: Use caution opening links or attachments
>
>
> [+cc Vidya]
>
> On Sun, Dec 26, 2021 at 03:49:10PM +0800, Jisheng Zhang wrote:
> > The integrated MSI Receiver enable register is always initialized in
> > dw_pcie_setup_rc() which is also called in resume code path, so we
> > don't need to save/restore the enable register during suspend/resume.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
> > ---
> >   drivers/pci/controller/dwc/pcie-tegra194.c | 9 ---------
> >   1 file changed, 9 deletions(-)
>
> Need an ACK from Nvidia folks.

Looks good to me.
I couldn't verify it on Nvidia platform as we are facing some issue with 
suspend/resume sequence.
I'll verify and update as soon as I could get suspend/resume working.

Acked-by: Vidya Sagar <vidyas@xxxxxxxxxx>

- Vidya Sagar
> Lorenzo
>
> > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> > index 904976913081..678898985319 100644
> > --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> > @@ -186,8 +186,6 @@
> >   #define N_FTS_VAL                                    52
> >   #define FTS_VAL                                              52
> >
> > -#define PORT_LOGIC_MSI_CTRL_INT_0_EN         0x828
> > -
> >   #define GEN3_EQ_CONTROL_OFF                  0x8a8
> >   #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_SHIFT       8
> >   #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_MASK        GENMASK(23, 8)
> > @@ -2189,9 +2187,6 @@ static int tegra_pcie_dw_suspend_noirq(struct device *dev)
> >        if (!pcie->link_state)
> >                return 0;
> >
> > -     /* Save MSI interrupt vector */
> > -     pcie->msi_ctrl_int = dw_pcie_readl_dbi(&pcie->pci,
> > -                                            PORT_LOGIC_MSI_CTRL_INT_0_EN);
> >        tegra_pcie_downstream_dev_to_D0(pcie);
> >        tegra_pcie_dw_pme_turnoff(pcie);
> >        tegra_pcie_unconfig_controller(pcie);
> > @@ -2223,10 +2218,6 @@ static int tegra_pcie_dw_resume_noirq(struct device *dev)
> >        if (ret < 0)
> >                goto fail_host_init;
> >
> > -     /* Restore MSI interrupt vector */
> > -     dw_pcie_writel_dbi(&pcie->pci, PORT_LOGIC_MSI_CTRL_INT_0_EN,
> > -                        pcie->msi_ctrl_int);
> > -
> >        return 0;
> >
> >   fail_host_init:
> > --
> > 2.34.1