Include the function pointer name in the subject so it's a little more
specific.
On Tue, Mar 26, 2024 at 11:45:38AM +0900, Yoshihiro Shimoda wrote:
> This driver can reuse other R-Car Gen4 SoC support. However, some
> initializing settings differs between r8a779f0 and others. So, add
> a new function pointer start_link_enable() to support other R-Car
> Gen4 SoC in the future. No behavior changes.
Make it clear here what the new SoC is. I think it's r8a779f0, but
you have to read the patch and look for the new .compatible string to
figure that out.
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> ---
> drivers/pci/controller/dwc/pcie-rcar-gen4.c | 57 +++++++++++++++++++--
> 1 file changed, 52 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 0be760ed420b..a37613dd9ff4 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -53,9 +53,16 @@ struct rcar_gen4_pcie {
> void __iomem *base;
> struct platform_device *pdev;
> enum dw_pcie_device_mode mode;
> +
> + int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
> };
> #define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw)
>
> +struct rcar_gen4_pcie_platdata {
> + enum dw_pcie_device_mode mode;
> + int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
I think it's confusing to repeat "mode" and "start_link_enable" in
both rcar_gen4_pcie and rcar_gen4_pcie_platdata. I know several other
drivers use this pattern, but I think it is simpler overall to just
save the pointer directly, e.g.,
imx6_pcie_probe
imx6_pcie->drvdata = of_device_get_match_data(dev);
ls_pcie_probe
pcie->drvdata = of_device_get_match_data(dev);
tegra_pcie_dw_probe
data = of_device_get_match_data(dev);
pcie->of_data = (struct tegra_pcie_dw_of_data *)data;
So I think the best thing would be to add struct
rcar_gen4_pcie_platdata, *move* rcar_gen4_pcie.mode there, and save a
pointer to the rcar_gen4_pcie_platdata in struct rcar_gen4_pcie.
That could be its own separate patch, which is nice on its own because
it gets rid of the (void *) casts in rcar_gen4_pcie_of_match[].
Then add .start_link_enable() (or .ltssm_enable(), see below) and the
r8a779f0 bits in another patch.
> +};
> +
> /* Common */
> static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar,
> bool enable)
> @@ -123,9 +130,13 @@ static int rcar_gen4_pcie_speed_change(struct dw_pcie *dw)
> static int rcar_gen4_pcie_start_link(struct dw_pcie *dw)
> {
> struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
> - int i, changes;
> + int i, changes, ret;
>
> - rcar_gen4_pcie_ltssm_enable(rcar, true);
> + if (rcar->start_link_enable) {
> + ret = rcar->start_link_enable(rcar);
This looks basically like what qcom does:
qcom_pcie_start_link
if (pcie->cfg->ops->ltssm_enable)
pcie->cfg->ops->ltssm_enable(pcie)
Can you copy that and use the same name for the pointer and function
name (.ltssm_enable, .*_ltssm_enable())?
> + if (ret)
> + return ret;
> + }
>
> /*
> * Require direct speed change with retrying here if the link_gen is
> @@ -437,7 +448,10 @@ static void rcar_gen4_remove_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
> /* Common */
> static int rcar_gen4_add_dw_pcie(struct rcar_gen4_pcie *rcar)
> {
> - rcar->mode = (uintptr_t)of_device_get_match_data(&rcar->pdev->dev);
> + const struct rcar_gen4_pcie_platdata *pd = of_device_get_match_data(&rcar->pdev->dev);
> +
> + rcar->mode = pd->mode;
> + rcar->start_link_enable = pd->start_link_enable;
>
> switch (rcar->mode) {
> case DW_PCIE_RC_TYPE:
> @@ -500,14 +514,47 @@ static void rcar_gen4_pcie_remove(struct platform_device *pdev)
> rcar_gen4_pcie_unprepare(rcar);
> }
>
> +static int r8a779f0_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
> +{
> + rcar_gen4_pcie_ltssm_enable(rcar, true);
Previously we called rcar_gen4_pcie_ltssm_enable() for
"renesas,rcar-gen4-pcie" and "renesas,rcar-gen4-pcie-ep". But after
this patch, it looks like we only call it for "renesas,r8a779f0-pcie"
and "renesas,r8a779f0-pcie-ep"?
> +
> + return 0;
> +}
> +
> +static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie = {
> + .mode = DW_PCIE_RC_TYPE,
> + .start_link_enable = r8a779f0_pcie_start_link_enable,
> +};
> +
> +static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie_ep = {
> + .mode = DW_PCIE_EP_TYPE,
> + .start_link_enable = r8a779f0_pcie_start_link_enable,
> +};
> +
> +static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie = {
> + .mode = DW_PCIE_RC_TYPE,
> +};
> +
> +static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie_ep = {
> + .mode = DW_PCIE_EP_TYPE,
> +};
> +
> static const struct of_device_id rcar_gen4_pcie_of_match[] = {
> + {
> + .compatible = "renesas,r8a779f0-pcie",
> + .data = &platdata_r8a779f0_pcie,
> + },
> + {
> + .compatible = "renesas,r8a779f0-pcie-ep",
> + .data = &platdata_r8a779f0_pcie_ep,
> + },
> {
> .compatible = "renesas,rcar-gen4-pcie",
> - .data = (void *)DW_PCIE_RC_TYPE,
> + .data = &platdata_rcar_gen4_pcie,
> },
> {
> .compatible = "renesas,rcar-gen4-pcie-ep",
> - .data = (void *)DW_PCIE_EP_TYPE,
> + .data = &platdata_rcar_gen4_pcie_ep,
> },
> {},
> };
> --
> 2.25.1
>
