Re: [PATCH v2 08/15] PCI: rcar-gen4: Add a controller reinitialization callback

[Koichiro Den]

On Sun, Oct 04, 2026 at 01:54:59AM +0200, Marek Vasut wrote:
> On 9/28/26 6:52 PM, Koichiro Den wrote:
> > Root Port recovery needs to reset and restore the controller while
> > keeping the clocks enabled and the Gen5 PHY initialized. Reusing .init()
> > would acquire these resources again, while calling .deinit() first would
> > make the APP registers inaccessible to interrupt handling.
> > 
> > Add a per-SoC .reinit() callback that repeats the power reset and register
> > setup without acquiring or releasing resources. Use the same reset and
> > register setup helpers as .init().
> > 
> > Signed-off-by: Koichiro Den <den@xxxxxxxxxxxxx>
> > ---
> > Changes in v2:
> >    - Adapt to the per-SoC .init()/.deinit() callbacks in next-20260925.
> >      Add .reinit() for recovery without changing their resource ownership
> >      or taking another PHY initialization reference.
> >    - Move hardware setup extraction and Gen5 initialization cleanup into
> >      preceding patches. This patch only adds the callback and its
> >      implementations.
> Could we introduce .configure callback instead, and deduplicate the two
> rcar_{gen4_v4h_v4m,gen5}_pcie_reinit() functions ? What do you think ?

Agreed, that is cleaner. Thanks for the suggestion.

> 
> This kind of a change (this would likely require folding this patch into
> 09/15):

Yes. With that change rcar_gen4_pcie_common_reinit() would have no caller in
this patch and compiler would complain, so yes, I'll fold this patch into 09/15.

Thanks for the review!

Best regards,
Koichiro Den

> 
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 3d667f25fb32e..3691c2ddbf6bc 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -100,7 +100,7 @@ struct rcar_gen4_pcie_drvdata {
>         int (*init)(struct rcar_gen4_pcie *rcar);
>         void (*deinit)(struct rcar_gen4_pcie *rcar);
>         /* Reset and restore registers while clocks and PHY remain
> initialized. */
> -       int (*reinit)(struct rcar_gen4_pcie *rcar);
> +       void (*configure)(struct rcar_gen4_pcie *rcar);
>         int (*ltssm_control)(struct rcar_gen4_pcie *rcar, bool enable);
>         int (*speed_control)(struct rcar_gen4_pcie *rcar);
>         enum dw_pcie_device_mode mode;
> @@ -326,6 +326,20 @@ static void rcar_gen4_pcie_common_deinit(struct
> rcar_gen4_pcie *rcar)
>         clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, dw->core_clks);
>  }
> 
> +static int rcar_gen4_pcie_common_reinit(struct rcar_gen4_pcie *rcar)
> +{
> +       int ret;
> +
> +       ret = rcar_gen4_pcie_reset(rcar);
> +       if (ret)
> +               return ret;
> +
> +       if (rcar->drvdata->configure)
> +               rcar->drvdata->configure(rcar);
> +
> +       return 0;
> +}
> +
>  static void rcar_gen4_v4h_v4m_pcie_configure(struct rcar_gen4_pcie *rcar)
>  {
>         struct dw_pcie *dw = &rcar->dw;
> @@ -343,19 +357,6 @@ static void rcar_gen4_v4h_v4m_pcie_configure(struct
> rcar_gen4_pcie *rcar)
>         writel(val, rcar->base + PCIEPWRMNGCTRL);
>  }
> 
> -static int rcar_gen4_v4h_v4m_pcie_reinit(struct rcar_gen4_pcie *rcar)
> -{
> -       int ret;
> -
> -       ret = rcar_gen4_pcie_reset(rcar);
> -       if (ret)
> -               return ret;
> -
> -       rcar_gen4_v4h_v4m_pcie_configure(rcar);
> -
> -       return 0;
> -}
> -
>  static int rcar_gen4_v4h_v4m_pcie_init(struct rcar_gen4_pcie *rcar)
>  {
>         int ret;
> @@ -400,19 +401,6 @@ static void rcar_gen5_pcie_configure(struct
> rcar_gen4_pcie *rcar)
>         writel(val, rcar->base + PCIEPWRMNGCTRL);
>  }
> 
> -static int rcar_gen5_pcie_reinit(struct rcar_gen4_pcie *rcar)
> -{
> -       int ret;
> -
> -       ret = rcar_gen4_pcie_reset(rcar);
> -       if (ret)
> -               return ret;
> -
> -       rcar_gen5_pcie_configure(rcar);
> -
> -       return 0;
> -}
> -
>  static int rcar_gen5_pcie_init(struct rcar_gen4_pcie *rcar)
>  {
>         int ret;
> @@ -1133,7 +1121,6 @@ static int rcar_gen4_pcie_ltssm_control(struct
> rcar_gen4_pcie *rcar, bool enable
>  static struct rcar_gen4_pcie_drvdata drvdata_r8a779f0_pcie = {
>         .init = rcar_gen4_pcie_common_init,
>         .deinit = rcar_gen4_pcie_common_deinit,
> -       .reinit = rcar_gen4_pcie_reset,
>         .ltssm_control = r8a779f0_pcie_ltssm_control,
>         .speed_control = rcar_gen4_pcie_speed_control,
>         .mode = DW_PCIE_RC_TYPE,
> @@ -1142,7 +1129,6 @@ static struct rcar_gen4_pcie_drvdata
> drvdata_r8a779f0_pcie = {
>  static struct rcar_gen4_pcie_drvdata drvdata_r8a779f0_pcie_ep = {
>         .init = rcar_gen4_pcie_common_init,
>         .deinit = rcar_gen4_pcie_common_deinit,
> -       .reinit = rcar_gen4_pcie_reset,
>         .ltssm_control = r8a779f0_pcie_ltssm_control,
>         .speed_control = rcar_gen4_pcie_speed_control,
>         .mode = DW_PCIE_EP_TYPE,
> @@ -1151,7 +1137,7 @@ static struct rcar_gen4_pcie_drvdata
> drvdata_r8a779f0_pcie_ep = {
>  static struct rcar_gen4_pcie_drvdata drvdata_rcar_gen4_pcie = {
>         .init = rcar_gen4_v4h_v4m_pcie_init,
>         .deinit = rcar_gen4_pcie_common_deinit,
> -       .reinit = rcar_gen4_v4h_v4m_pcie_reinit,
> +       .configure = rcar_gen4_v4h_v4m_pcie_configure,
>         .ltssm_control = rcar_gen4_pcie_ltssm_control,
>         .speed_control = rcar_gen4_pcie_speed_control,
>         .mode = DW_PCIE_RC_TYPE,
> @@ -1160,7 +1146,7 @@ static struct rcar_gen4_pcie_drvdata
> drvdata_rcar_gen4_pcie = {
>  static struct rcar_gen4_pcie_drvdata drvdata_rcar_gen4_pcie_ep = {
>         .init = rcar_gen4_v4h_v4m_pcie_init,
>         .deinit = rcar_gen4_pcie_common_deinit,
> -       .reinit = rcar_gen4_v4h_v4m_pcie_reinit,
> +       .configure = rcar_gen4_v4h_v4m_pcie_configure,
>         .ltssm_control = rcar_gen4_pcie_ltssm_control,
>         .speed_control = rcar_gen4_pcie_speed_control,
>         .mode = DW_PCIE_EP_TYPE,
> @@ -1169,7 +1155,7 @@ static struct rcar_gen4_pcie_drvdata
> drvdata_rcar_gen4_pcie_ep = {
>  static struct rcar_gen4_pcie_drvdata drvdata_rcar_gen5_pcie = {
>         .init = rcar_gen5_pcie_init,
>         .deinit = rcar_gen5_pcie_deinit,
> -       .reinit = rcar_gen5_pcie_reinit,
> +       .configure = rcar_gen5_pcie_configure,
>         .ltssm_control = rcar_gen5_pcie_ltssm_control,
>         .speed_control = rcar_gen5_pcie_speed_control,
>         .mode = DW_PCIE_RC_TYPE,
>