soc: renesas: rcar-sysc: Enable Clock Domain for I/O devices

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>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

diff --git a/drivers/soc/renesas/rcar-sysc.c b/drivers/soc/renesas/rcar-sysc.c
index 4e760d63f2abd93fa9778d7caf7032fe0e72bcb0..0d49a25de740fbf829bb99d6d3edc212bbd18c50 100644 (file)
--- 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;
+
 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);