diff mbox series

[03/14] pinctrl: renesas: Fix pin control matching on R-Car H3e-2G

Message ID ab1acd836e990c536ff3a8c715ce57363d3ff8cb.1623315732.git.geert+renesas@glider.be (mailing list archive)
State New
Delegated to: Geert Uytterhoeven
Headers show
Series arm64: renesas: Add support for R Car H3e 2G-and M3e-2G | expand

Commit Message

Geert Uytterhoeven June 10, 2021, 9:37 a.m. UTC
As R-Car H3 ES1.x (R8A77950) and R-Car ES2.0+ (R8A77951) use the same
compatible value, the pin control driver relies on soc_device_match()
with soc_id = "r8a7795" and the (non)matching of revision = "ES1.*" to
match with and distinguish between the two SoC variants.  The
corresponding entries in the normal of_match_table are present only to
make the optional sanity checks work.

The R-Car H3e-2G (R8A779M1) SoC is a different grading of the R-Car H3
ES3.0 (R8A77951) SoC.  It uses the same compatible values for individual
devices, but has an additional compatible value for the root node.
When running on an R-Car H3e-2G SoC, soc_device_match() with soc_id =
"r8a7795" does not return a match.  Hence the pin control driver falls
back to the normal of_match_table, and, as the R8A77950 entry is listed
first, incorrectly uses the sub-driver for R-Car H3 ES1.x.

Fix this by moving the entry for R8A77951 before the entry for R8A77950.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/pinctrl/renesas/core.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

Comments

Laurent Pinchart June 14, 2021, 6:38 p.m. UTC | #1
Hi Geert,

Thank you for the patch.

On Thu, Jun 10, 2021 at 11:37:16AM +0200, Geert Uytterhoeven wrote:
> As R-Car H3 ES1.x (R8A77950) and R-Car ES2.0+ (R8A77951) use the same
> compatible value, the pin control driver relies on soc_device_match()
> with soc_id = "r8a7795" and the (non)matching of revision = "ES1.*" to
> match with and distinguish between the two SoC variants.  The
> corresponding entries in the normal of_match_table are present only to
> make the optional sanity checks work.
> 
> The R-Car H3e-2G (R8A779M1) SoC is a different grading of the R-Car H3
> ES3.0 (R8A77951) SoC.  It uses the same compatible values for individual
> devices, but has an additional compatible value for the root node.
> When running on an R-Car H3e-2G SoC, soc_device_match() with soc_id =
> "r8a7795" does not return a match.  Hence the pin control driver falls
> back to the normal of_match_table, and, as the R8A77950 entry is listed
> first, incorrectly uses the sub-driver for R-Car H3 ES1.x.
> 
> Fix this by moving the entry for R8A77951 before the entry for R8A77950.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

I wonder if this means we could drop the second entry in the quirks
array, in sh_pfc_quirk_match().

> ---
>  drivers/pinctrl/renesas/core.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/pinctrl/renesas/core.c b/drivers/pinctrl/renesas/core.c
> index 5ccc49b387f17eb9..9adb97065704270d 100644
> --- a/drivers/pinctrl/renesas/core.c
> +++ b/drivers/pinctrl/renesas/core.c
> @@ -571,17 +571,21 @@ static const struct of_device_id sh_pfc_of_table[] = {
>  		.data = &r8a7794_pinmux_info,
>  	},
>  #endif
> -/* Both r8a7795 entries must be present to make sanity checks work */
> -#ifdef CONFIG_PINCTRL_PFC_R8A77950
> +/*
> + * Both r8a7795 entries must be present to make sanity checks work, but only
> + * the first entry is actually used, for R-Car H3e.
> + * R-Car H3 ES1.x and ES2.0+ are matched using soc_device_match() instead.
> + */
> +#ifdef CONFIG_PINCTRL_PFC_R8A77951
>  	{
>  		.compatible = "renesas,pfc-r8a7795",
> -		.data = &r8a77950_pinmux_info,
> +		.data = &r8a77951_pinmux_info,
>  	},
>  #endif
> -#ifdef CONFIG_PINCTRL_PFC_R8A77951
> +#ifdef CONFIG_PINCTRL_PFC_R8A77950
>  	{
>  		.compatible = "renesas,pfc-r8a7795",
> -		.data = &r8a77951_pinmux_info,
> +		.data = &r8a77950_pinmux_info,
>  	},
>  #endif
>  #ifdef CONFIG_PINCTRL_PFC_R8A77960
Geert Uytterhoeven June 14, 2021, 7:16 p.m. UTC | #2
Hi Laurent,

On Mon, Jun 14, 2021 at 8:38 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> On Thu, Jun 10, 2021 at 11:37:16AM +0200, Geert Uytterhoeven wrote:
> > As R-Car H3 ES1.x (R8A77950) and R-Car ES2.0+ (R8A77951) use the same
> > compatible value, the pin control driver relies on soc_device_match()
> > with soc_id = "r8a7795" and the (non)matching of revision = "ES1.*" to
> > match with and distinguish between the two SoC variants.  The
> > corresponding entries in the normal of_match_table are present only to
> > make the optional sanity checks work.
> >
> > The R-Car H3e-2G (R8A779M1) SoC is a different grading of the R-Car H3
> > ES3.0 (R8A77951) SoC.  It uses the same compatible values for individual
> > devices, but has an additional compatible value for the root node.
> > When running on an R-Car H3e-2G SoC, soc_device_match() with soc_id =
> > "r8a7795" does not return a match.  Hence the pin control driver falls
> > back to the normal of_match_table, and, as the R8A77950 entry is listed
> > first, incorrectly uses the sub-driver for R-Car H3 ES1.x.
> >
> > Fix this by moving the entry for R8A77951 before the entry for R8A77950.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Thanks!

> I wonder if this means we could drop the second entry in the quirks
> array, in sh_pfc_quirk_match().

As both R-Car H3 ES1.x and ES2.0+ use the same compatible value,
that function is designed (with the help of the __weak
r8a7795[01]_pinmux_info symbols) to fail, when booting a kernel
that lacks the right pin control driver.  It's less likely to happen
nowadays, since we gained separate Kconfig symbols.

Note that if you enable CONFIG_ARCH_R8A77950 but not
CONFIG_ARCH_R8A77951, you can still trick a kernel running on R-Car
H3e-2G into using the wrong pin control driver, which will usually
cause something to fail during boot.  Perhaps the time is ripe to
drop the safety net; need to thing about that with a fresh mind,
after a morning coffee...

> > --- a/drivers/pinctrl/renesas/core.c
> > +++ b/drivers/pinctrl/renesas/core.c
> > @@ -571,17 +571,21 @@ static const struct of_device_id sh_pfc_of_table[] = {
> >               .data = &r8a7794_pinmux_info,
> >       },
> >  #endif
> > -/* Both r8a7795 entries must be present to make sanity checks work */
> > -#ifdef CONFIG_PINCTRL_PFC_R8A77950
> > +/*
> > + * Both r8a7795 entries must be present to make sanity checks work, but only
> > + * the first entry is actually used, for R-Car H3e.
> > + * R-Car H3 ES1.x and ES2.0+ are matched using soc_device_match() instead.
> > + */
> > +#ifdef CONFIG_PINCTRL_PFC_R8A77951
> >       {
> >               .compatible = "renesas,pfc-r8a7795",
> > -             .data = &r8a77950_pinmux_info,
> > +             .data = &r8a77951_pinmux_info,
> >       },
> >  #endif
> > -#ifdef CONFIG_PINCTRL_PFC_R8A77951
> > +#ifdef CONFIG_PINCTRL_PFC_R8A77950
> >       {
> >               .compatible = "renesas,pfc-r8a7795",
> > -             .data = &r8a77951_pinmux_info,
> > +             .data = &r8a77950_pinmux_info,
> >       },
> >  #endif
> >  #ifdef CONFIG_PINCTRL_PFC_R8A77960

Gr{oetje,eeting}s,

                        Geert
diff mbox series

Patch

diff --git a/drivers/pinctrl/renesas/core.c b/drivers/pinctrl/renesas/core.c
index 5ccc49b387f17eb9..9adb97065704270d 100644
--- a/drivers/pinctrl/renesas/core.c
+++ b/drivers/pinctrl/renesas/core.c
@@ -571,17 +571,21 @@  static const struct of_device_id sh_pfc_of_table[] = {
 		.data = &r8a7794_pinmux_info,
 	},
 #endif
-/* Both r8a7795 entries must be present to make sanity checks work */
-#ifdef CONFIG_PINCTRL_PFC_R8A77950
+/*
+ * Both r8a7795 entries must be present to make sanity checks work, but only
+ * the first entry is actually used, for R-Car H3e.
+ * R-Car H3 ES1.x and ES2.0+ are matched using soc_device_match() instead.
+ */
+#ifdef CONFIG_PINCTRL_PFC_R8A77951
 	{
 		.compatible = "renesas,pfc-r8a7795",
-		.data = &r8a77950_pinmux_info,
+		.data = &r8a77951_pinmux_info,
 	},
 #endif
-#ifdef CONFIG_PINCTRL_PFC_R8A77951
+#ifdef CONFIG_PINCTRL_PFC_R8A77950
 	{
 		.compatible = "renesas,pfc-r8a7795",
-		.data = &r8a77951_pinmux_info,
+		.data = &r8a77950_pinmux_info,
 	},
 #endif
 #ifdef CONFIG_PINCTRL_PFC_R8A77960