| Message ID | 1432839219-475-14-git-send-email-geert+renesas@glider.be (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Quoting Geert Uytterhoeven (2015-05-28 11:53:38) > Currently the CPG Clock Domain code looks for MSTP clocks to power > manage a device. > > Unfortunately, on R-Mobile APE6 (r8a73a4) and SH-Mobile AG5 (sh73a0), > the Bus State Controller (BSC) is not power-managed by an MSTP clock, > but by a plain CPG clock (zb_clk). Add a special case to handle this, > so the clock is properly managed, and devices connected to the BSC work > as expected. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > --- > v2: > - New. > --- > drivers/clk/shmobile/clk-mstp.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/clk/shmobile/clk-mstp.c b/drivers/clk/shmobile/clk-mstp.c > index 619f3eccefd4884f..19e2b11953383587 100644 > --- a/drivers/clk/shmobile/clk-mstp.c > +++ b/drivers/clk/shmobile/clk-mstp.c > @@ -258,6 +258,10 @@ int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev) > "renesas,cpg-mstp-clocks")) > goto found; > > + /* BSC on r8a73a4/sh73a0 uses zb_clk instead of an mstp clock*/ > + if (!strcmp(clkspec.np->name, "zb_clk")) > + goto found; Hello Geert, Is the driver the right place to handle this corner case? What do you think about linking zb_clk up to the bsc devicetree node for r8a73a4/sh73a0? Regards, Mike > + > of_node_put(clkspec.np); > i++; > } > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
Hi Mike, On Mon, Jun 22, 2015 at 10:05 PM, Michael Turquette <mturquette@linaro.org> wrote: Still sending email from Linaro, which will cause me to receive an autoreply? > Quoting Geert Uytterhoeven (2015-05-28 11:53:38) >> Currently the CPG Clock Domain code looks for MSTP clocks to power >> manage a device. >> >> Unfortunately, on R-Mobile APE6 (r8a73a4) and SH-Mobile AG5 (sh73a0), >> the Bus State Controller (BSC) is not power-managed by an MSTP clock, >> but by a plain CPG clock (zb_clk). Add a special case to handle this, >> so the clock is properly managed, and devices connected to the BSC work >> as expected. >> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> >> --- >> v2: >> - New. >> --- >> drivers/clk/shmobile/clk-mstp.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/clk/shmobile/clk-mstp.c b/drivers/clk/shmobile/clk-mstp.c >> index 619f3eccefd4884f..19e2b11953383587 100644 >> --- a/drivers/clk/shmobile/clk-mstp.c >> +++ b/drivers/clk/shmobile/clk-mstp.c >> @@ -258,6 +258,10 @@ int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev) >> "renesas,cpg-mstp-clocks")) >> goto found; >> >> + /* BSC on r8a73a4/sh73a0 uses zb_clk instead of an mstp clock*/ >> + if (!strcmp(clkspec.np->name, "zb_clk")) >> + goto found; > > Hello Geert, > > Is the driver the right place to handle this corner case? What do you > think about linking zb_clk up to the bsc devicetree node for > r8a73a4/sh73a0? It already is linked: bsc: bus@fec10000 { compatible = "renesas,bsc-r8a73a4", "renesas,bsc", "simple-pm-bus"; #address-cells = <1>; #size-cells = <1>; ranges = <0 0 0 0x20000000>; reg = <0 0xfec10000 0 0x400>; clocks = <&zb_clk>; power-domains = <&pd_c4>; }; https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/r8a73a4.dtsi#n446 But without this hack in clk-mstp, the clock domain controller doesn't know it can use this clock for power management like an ordinary mstp clock. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
diff --git a/drivers/clk/shmobile/clk-mstp.c b/drivers/clk/shmobile/clk-mstp.c index 619f3eccefd4884f..19e2b11953383587 100644 --- a/drivers/clk/shmobile/clk-mstp.c +++ b/drivers/clk/shmobile/clk-mstp.c @@ -258,6 +258,10 @@ int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev) "renesas,cpg-mstp-clocks")) goto found; + /* BSC on r8a73a4/sh73a0 uses zb_clk instead of an mstp clock*/ + if (!strcmp(clkspec.np->name, "zb_clk")) + goto found; + of_node_put(clkspec.np); i++; }
Currently the CPG Clock Domain code looks for MSTP clocks to power manage a device. Unfortunately, on R-Mobile APE6 (r8a73a4) and SH-Mobile AG5 (sh73a0), the Bus State Controller (BSC) is not power-managed by an MSTP clock, but by a plain CPG clock (zb_clk). Add a special case to handle this, so the clock is properly managed, and devices connected to the BSC work as expected. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- v2: - New. --- drivers/clk/shmobile/clk-mstp.c | 4 ++++ 1 file changed, 4 insertions(+)