Hi Manivannan,
> From: Manivannan Sadhasivam, Sent: Saturday, May 11, 2024 4:38 PM
>
> PCI: rcar-gen4: Move LTSSM handling to ltssm_control() callback
>
> On Mon, Apr 15, 2024 at 05:11:33PM +0900, Yoshihiro Shimoda wrote:
> > This driver can reuse other R-Car Gen4 SoCs support like r8a779g0 and
> > r8a779h0. However, r8a779g0 and r8a779h0 require other initializing
> > settings that differ than r8a779f0. So, add a new function pointer
> > .ltssm_enable() for it.
> >
> > After applied this patch, probing SoCs by rcar_gen4_pcie_of_match[]
> > will be changed like below:
> >
> > - r8a779f0 as "renesas,r8a779f0-pcie" and "renesas,r8a779f0-pcie-ep"
> >
> > Existing dts files have the compatible above. So, no behavior changes.
> >
>
> How about:
>
> Sequence for controlling the LTSSM state machine is going to change for SoCs
> like r8a779f0. So let's move the LTSSM code to a new callback ltssm_control()
> and populate it for each SoCs.
>
> This also warrants the addition of new compatibles for r8a779g0 and r8a779h0.
> But since they are already part of the DT binding, it won't make any difference.
Thank you for suggestion. It good to me. I'll use this description.
> > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> > ---
> > drivers/pci/controller/dwc/pcie-rcar-gen4.c | 41 ++++++++++++++++++---
> > 1 file changed, 36 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > index 3da0a844e1b6..980a916933d6 100644
> > --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > @@ -48,7 +48,9 @@
> > #define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET 0x1000
> > #define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET 0x800
> >
> > +struct rcar_gen4_pcie;
> > struct rcar_gen4_pcie_drvdata {
> > + int (*ltssm_enable)(struct rcar_gen4_pcie *rcar);
>
> int (*ltssm_control)(struct rcar_gen4_pcie *rcar, bool enable);
I got it.
> > enum dw_pcie_device_mode mode;
> > };
> >
> > @@ -61,8 +63,8 @@ struct rcar_gen4_pcie {
> > #define to_rcar_gen4_pcie(_dw) container_of(_dw, struct rcar_gen4_pcie, dw)
> >
> > /* Common */
> > -static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar,
> > - bool enable)
> > +static void rcar_gen4_pcie_ltssm_control(struct rcar_gen4_pcie *rcar,
> > + bool enable)
> > {
> > u32 val;
> >
> > @@ -127,9 +129,13 @@ 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->drvdata->ltssm_enable) {
> > + ret = rcar->drvdata->ltssm_enable(rcar);
> > + if (ret)
> > + return ret;
> > + }
> >
> > /*
> > * Require direct speed change with retrying here if the link_gen is
> > @@ -157,7 +163,7 @@ static void rcar_gen4_pcie_stop_link(struct dw_pcie *dw)
> > {
> > struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
> >
> > - rcar_gen4_pcie_ltssm_enable(rcar, false);
> > + rcar_gen4_pcie_ltssm_control(rcar, false);
>
> You should use the callback here as like above.
I got it. JFYI, the current patch used rcar_gen4_pcie_ltssm_control(rcar, false) for
both r8a779f0 and r8a779g0. So, I'll modify the rcar_gen4_pcie_ltssm_enable() for case of false.
> > }
> >
> > static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar)
> > @@ -504,6 +510,23 @@ static void rcar_gen4_pcie_remove(struct platform_device *pdev)
> > rcar_gen4_pcie_unprepare(rcar);
> > }
> >
> > +static int r8a779f0_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar)
> > +{
> > + rcar_gen4_pcie_ltssm_control(rcar, true);
> > +
> > + return 0;
> > +}
> > +
> > +static struct rcar_gen4_pcie_drvdata drvdata_r8a779f0_pcie = {
> > + .ltssm_enable = r8a779f0_pcie_ltssm_enable,
>
> Just pass rcar_gen4_pcie_ltssm_control() directly.
I got it.
Best regards,
Yoshihiro Shimoda
> - Mani
>
> --
> மணிவண்ணன் சதாசிவம்
