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

Geert Uytterhoeven
2016-04-20T12:02:44Z

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;
+
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