Re: [PATCH v6 05/11] soc: renesas: rcar-sysc: Enable Clock Domain for I/O devices

Ulf Hansson
2016-04-22T07:28:18Z

On 20 April 2016 at 14:02, Geert Uytterhoeven <geert+renesas@glider.be> wrote:
> On R-Car H3, some power areas (e.g. A3VP) contain I/O devices, which are
> also part of the CPG/MSSR Clock Domain.
> On all R-Car SoCs, devices in the "always-on" PM Domain are part of the
> Clock Domain served by the CPG/MSSR or CPG/MSTP driver.
>
> Hook up the CPG/MSTP or CPG/MSSR Clock Domain attach/detach callbacks to
> enable power management using module clocks. Which callback to hook up
> depends on the presence of device nodes compatible with
> "renesas,cpg-mstp-clocks". This clears the path for a future migration
> from the CPG/MSTP to the CPG/MSSR driver on R-Car H1 and
> Gen2.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> v6:
> - Add Reviewed-by,
> - Rebased,
>
> v5:
> - Revert v4 changes,
> - Use either the cpg_mssr_*() or cpg_mstp_*() callbacks,
> - Drop dependency on r8a7795, as this is used for the "always-on" PM
> Domain on R-Car H1 and Gen2, too,
>
> v4:
> - Remove the explicit dependency on the CPG/MSSR driver by forwarding
> the attach/detach callbacks to the parent PM Domain.
> If deemed reusable, rcar_sysc_{at,de}tach_dev() can be moved to
> common genpd code later.
>
> v3:
> - Hook up the CPG/MSSR Clock Domain attach/detach callbacks instead of
> using our own copies,
>
> v2:
> - New.
> ---
> drivers/soc/renesas/rcar-sysc.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/soc/renesas/rcar-sysc.c b/drivers/soc/renesas/rcar-sysc.c
> index 4e760d63f2abd93f..0d49a25de740fbf8 100644
> --- a/drivers/soc/renesas/rcar-sysc.c
> +++ b/drivers/soc/renesas/rcar-sysc.c
> @@ -9,6 +9,7 @@
> * for more details.
> */
>
> +#include <linux/clk/renesas.h>
> #include <linux/delay.h>
> #include <linux/err.h>
> #include <linux/mm.h>
> @@ -217,6 +218,8 @@ static int rcar_sysc_pd_power_on(struct generic_pm_domain *genpd)
> return rcar_sysc_power_up(&pd->ch);
> }
>
> +static bool has_cpg_mstp;
> +

That's seems lazy. :-)

Sure you can provide this as an input parameter to
rcar_sysc_pd_setup() instead, no?

> static void __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
> {
> struct generic_pm_domain *genpd = &pd->genpd;
> @@ -248,6 +251,18 @@ static void __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
> gov = &pm_domain_always_on_gov;
> }
>
> + if (!(pd->flags & (PD_CPU | PD_SCU))) {
> + /* Enable Clock Domain for I/O devices */
> + genpd->flags = GENPD_FLAG_PM_CLK;
> + if (has_cpg_mstp) {
> + genpd->attach_dev = cpg_mstp_attach_dev;
> + genpd->detach_dev = cpg_mstp_detach_dev;
> + } else {
> + genpd->attach_dev = cpg_mssr_attach_dev;
> + genpd->detach_dev = cpg_mssr_detach_dev;
> + }
> + }
> +
> genpd->power_off = rcar_sysc_pd_power_off;
> genpd->power_on = rcar_sysc_pd_power_on;
>
> @@ -294,6 +309,9 @@ static int __init rcar_sysc_pd_init(void)
>
> info = match->data;
>
> + has_cpg_mstp = of_find_compatible_node(NULL, NULL,
> + "renesas,cpg-mstp-clocks");
> +
> base = of_iomap(np, 0);
> if (!base) {
> pr_warn("%s: Cannot map regs\n", np->full_name);
> --
> 1.9.1
>

Kind regards
Uffe