On R-Car Gen3 systems, PSCI system suspend powers down the SoC, possibly
losing clock configuration. Hence add a notifier chain that can be used
by core clocks to save/restore clock state during system suspend/resume.
The implementation of the actual clock state save/restore operations is
clock-specific, and to be registered with the notifier chain in the SoC
or family-specific cpg_mssr_info.cpg_clk_register() callback.
Signed-off-by: Geert Uytterhoeven <geert+rene...@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund+rene...@ragnatech.se>
---
v3:
- Drop RFC state,
- Add Tested-by,
v2:
- New.
---
drivers/clk/renesas/rcar-gen2-cpg.c | 7 +++----
drivers/clk/renesas/rcar-gen2-cpg.h | 6 +++---
drivers/clk/renesas/rcar-gen3-cpg.c | 3 ++-
drivers/clk/renesas/rcar-gen3-cpg.h | 3 ++-
drivers/clk/renesas/renesas-cpg-mssr.c | 12 +++++++++++-
drivers/clk/renesas/renesas-cpg-mssr.h | 3 ++-
6 files changed, 23 insertions(+), 11 deletions(-)
diff --git a/drivers/clk/renesas/rcar-gen2-cpg.c
b/drivers/clk/renesas/rcar-gen2-cpg.c
index 123b1e622179308e..feb14579a71b3bf4 100644
--- a/drivers/clk/renesas/rcar-gen2-cpg.c
+++ b/drivers/clk/renesas/rcar-gen2-cpg.c
@@ -262,10 +262,9 @@ static unsigned int cpg_pll0_div __initdata;
static u32 cpg_mode __initdata;
struct clk * __init rcar_gen2_cpg_clk_register(struct device *dev,
- const struct cpg_core_clk *core,
- const struct cpg_mssr_info *info,
- struct clk **clks,
- void __iomem *base)
+ const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
+ struct clk **clks, void __iomem *base,
+ struct raw_notifier_head *notifiers)
{
const struct clk_div_table *table = NULL;
const struct clk *parent;
diff --git a/drivers/clk/renesas/rcar-gen2-cpg.h
b/drivers/clk/renesas/rcar-gen2-cpg.h
index 9eba07ff8b11e20e..020a3baad0154231 100644
--- a/drivers/clk/renesas/rcar-gen2-cpg.h
+++ b/drivers/clk/renesas/rcar-gen2-cpg.h
@@ -34,9 +34,9 @@ struct rcar_gen2_cpg_pll_config {
};
struct clk *rcar_gen2_cpg_clk_register(struct device *dev,
- const struct cpg_core_clk *core,
- const struct cpg_mssr_info *info,
- struct clk **clks, void __iomem *base);
+ const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
+ struct clk **clks, void __iomem *base,
+ struct raw_notifier_head *notifiers);
int rcar_gen2_cpg_init(const struct rcar_gen2_cpg_pll_config *config,
unsigned int pll0_div, u32 mode);
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c
b/drivers/clk/renesas/rcar-gen3-cpg.c
index 9511058165475dd7..139985257003bfad 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.c
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -265,7 +265,8 @@ static const struct soc_device_attribute cpg_quirks_match[]
__initconst = {
struct clk * __init rcar_gen3_cpg_clk_register(struct device *dev,
const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
- struct clk **clks, void __iomem *base)
+ struct clk **clks, void __iomem *base,
+ struct raw_notifier_head *notifiers)
{
const struct clk *parent;
unsigned int mult = 1;
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.h
b/drivers/clk/renesas/rcar-gen3-cpg.h
index d756ef8b78eb6c02..2e4284399f530f96 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.h
+++ b/drivers/clk/renesas/rcar-gen3-cpg.h
@@ -44,7 +44,8 @@ struct rcar_gen3_cpg_pll_config {
struct clk *rcar_gen3_cpg_clk_register(struct device *dev,
const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
- struct clk **clks, void __iomem *base);
+ struct clk **clks, void __iomem *base,
+ struct raw_notifier_head *notifiers);
int rcar_gen3_cpg_init(const struct rcar_gen3_cpg_pll_config *config,
unsigned int clk_extalr, u32 mode);
diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c
b/drivers/clk/renesas/renesas-cpg-mssr.c
index 15fc8679d3426f3e..485dce00a562d919 100644
--- a/drivers/clk/renesas/renesas-cpg-mssr.c
+++ b/drivers/clk/renesas/renesas-cpg-mssr.c
@@ -107,6 +107,7 @@ static const u16 srcr[] = {
* @num_core_clks: Number of Core Clocks in clks[]
* @num_mod_clks: Number of Module Clocks in clks[]
* @last_dt_core_clk: ID of the last Core Clock exported to DT
+ * @notifiers: Notifier chain to save/restore clock state for system resume
* @smstpcr_saved[].mask: Mask of SMSTPCR[] bits under our control
* @smstpcr_saved[].val: Saved values of SMSTPCR[]
*/
@@ -123,6 +124,7 @@ struct cpg_mssr_priv {
unsigned int num_mod_clks;
unsigned int last_dt_core_clk;
+ struct raw_notifier_head notifiers;
struct {
u32 mask;
u32 val;
@@ -312,7 +314,8 @@ static void __init cpg_mssr_register_core_clk(const struct
cpg_core_clk *core,
default:
if (info->cpg_clk_register)
clk = info->cpg_clk_register(dev, core, info,
- priv->clks, priv->base);
+ priv->clks, priv->base,
+ &priv->notifiers);
else
dev_err(dev, "%s has unsupported core clock type %u\n",
core->name, core->type);
@@ -726,6 +729,9 @@ static int cpg_mssr_suspend_noirq(struct device *dev)
readl(priv->base + SMSTPCR(reg));
}
+ /* Save core clocks */
+ raw_notifier_call_chain(&priv->notifiers, PM_EVENT_SUSPEND, NULL);
+
return 0;
}
@@ -739,6 +745,9 @@ static int cpg_mssr_resume_noirq(struct device *dev)
if (!psci_ops.cpu_suspend)
return 0;
+ /* Restore core clocks */
+ raw_notifier_call_chain(&priv->notifiers, PM_EVENT_RESUME, NULL);
+
/* Restore module clocks */
for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
mask = priv->smstpcr_saved[reg].mask;
@@ -822,6 +831,7 @@ static int __init cpg_mssr_probe(struct platform_device
*pdev)
priv->num_core_clks = info->num_total_core_clks;
priv->num_mod_clks = info->num_hw_mod_clks;
priv->last_dt_core_clk = info->last_dt_core_clk;
+ RAW_INIT_NOTIFIER_HEAD(&priv->notifiers);
for (i = 0; i < nclks; i++)
clks[i] = ERR_PTR(-ENOENT);
diff --git a/drivers/clk/renesas/renesas-cpg-mssr.h
b/drivers/clk/renesas/renesas-cpg-mssr.h
index 66528ce3eb373fca..0745b09303082ef9 100644
--- a/drivers/clk/renesas/renesas-cpg-mssr.h
+++ b/drivers/clk/renesas/renesas-cpg-mssr.h
@@ -127,7 +127,8 @@ struct cpg_mssr_info {
struct clk *(*cpg_clk_register)(struct device *dev,
const struct cpg_core_clk *core,
const struct cpg_mssr_info *info,
- struct clk **clks, void __iomem *base);
+ struct clk **clks, void __iomem *base,
+ struct raw_notifier_head *notifiers);
};
extern const struct cpg_mssr_info r8a7743_cpg_mssr_info;
--
2.7.4
