Re: [PATCH v5 05/11] soc: renesas: rcar-sysc: Enable Clock Domain for I/O devices

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Geert,

Thank you for the patch.

On Wednesday 13 Apr 2016 16:44:26 Geert Uytterhoeven 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>

> ---
> 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 a333ef4152428440..be83636ef2647947
> 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>
> @@ -222,6 +223,8 @@ static int rcar_sysc_pd_power_on(struct
> generic_pm_domain *genpd) return rcar_sysc_power_up(&pd->ch);
>  }
> 
> +static bool has_cpg_mstp;
> +
>  static void __init rcar_sysc_pd_setup(struct rcar_sysc_pd *pd)
>  {
>  	struct generic_pm_domain *genpd = &pd->genpd;
> @@ -253,6 +256,18 @@ 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;
> +		}
> +	}
> +
>  	pm_genpd_init(genpd, gov, false);
>  	genpd->dev_ops.active_wakeup = rcar_sysc_active_wakeup;
>  	genpd->power_off = rcar_sysc_pd_power_off;
> @@ -298,6 +313,9 @@ 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);

-- 
Regards,

Laurent Pinchart