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

[Marek Vasut]

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 ?

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

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,