[PATCH] clk: renesas: rcar-gen3: Replace SSCG caching with MDSEL/PE caching

[Marek Vasut]

Do not cache the single CPG MODE register bit 12, instead cache the
entire register value, and only pick the matching bit from the cached
value when core clock of type MDSEL or PE are used. Both MDSEL and PE
clock type currently define .offset field as 12 on Gen3, which means
this code will use bit 12 on Gen3 again, however there are additional
clock on Gen4 which use different bits, and having this flexibility
in place now will be useful when adding Gen4.

No functional change.

Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
 drivers/clk/renesas/clk-rcar-gen3.c | 18 +++++++++---------
 drivers/clk/renesas/rcar-gen3-cpg.h |  2 +-
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/renesas/clk-rcar-gen3.c b/drivers/clk/renesas/clk-rcar-gen3.c
index d778db6569d..9545e0a1435 100644
--- a/drivers/clk/renesas/clk-rcar-gen3.c
+++ b/drivers/clk/renesas/clk-rcar-gen3.c
@@ -55,6 +55,7 @@ static int gen3_clk_get_parent(struct gen3_clk_priv *priv, struct clk *clk,
 			       struct cpg_mssr_info *info, struct clk *parent)
 {
 	const struct cpg_core_clk *core;
+	u8 shift;
 	int ret;
 
 	if (!renesas_clk_is_mod(clk)) {
@@ -63,8 +64,9 @@ static int gen3_clk_get_parent(struct gen3_clk_priv *priv, struct clk *clk,
 			return ret;
 
 		if (core->type == CLK_TYPE_GEN3_MDSEL) {
+			shift = priv->cpg_mode & BIT(core->offset) ? 16 : 0;
 			parent->dev = clk->dev;
-			parent->id = core->parent >> (priv->sscg ? 16 : 0);
+			parent->id = core->parent >> shift;
 			parent->id &= 0xffff;
 			return 0;
 		}
@@ -183,6 +185,7 @@ static u64 gen3_clk_get_rate64(struct clk *clk)
 					priv->cpg_pll_config;
 	u32 value, div;
 	u64 rate = 0;
+	u8 shift;
 	int ret;
 
 	debug("%s[%i] Clock: id=%lu\n", __func__, __LINE__, clk->id);
@@ -277,11 +280,11 @@ static u64 gen3_clk_get_rate64(struct clk *clk)
 						"FIXED");
 
 	case CLK_TYPE_GEN3_MDSEL:
-		div = (core->div >> (priv->sscg ? 16 : 0)) & 0xffff;
+		shift = priv->cpg_mode & BIT(core->offset) ? 16 : 0;
+		div = (core->div >> shift) & 0xffff;
 		rate = gen3_clk_get_rate64(&parent) / div;
 		debug("%s[%i] PE clk: parent=%i div=%u => rate=%llu\n",
-		      __func__, __LINE__,
-		      (core->parent >> (priv->sscg ? 16 : 0)) & 0xffff,
+		      __func__, __LINE__, (core->parent >> shift) & 0xffff,
 		      div, rate);
 		return rate;
 
@@ -407,7 +410,6 @@ static int gen3_clk_probe(struct udevice *dev)
 	struct cpg_mssr_info *info =
 		(struct cpg_mssr_info *)dev_get_driver_data(dev);
 	fdt_addr_t rst_base;
-	u32 cpg_mode;
 	int ret;
 
 	priv->base = dev_read_addr_ptr(dev);
@@ -423,15 +425,13 @@ static int gen3_clk_probe(struct udevice *dev)
 	if (rst_base == FDT_ADDR_T_NONE)
 		return -EINVAL;
 
-	cpg_mode = readl(rst_base + info->reset_modemr_offset);
+	priv->cpg_mode = readl(rst_base + info->reset_modemr_offset);
 
 	priv->cpg_pll_config =
-		(struct rcar_gen3_cpg_pll_config *)info->get_pll_config(cpg_mode);
+		(struct rcar_gen3_cpg_pll_config *)info->get_pll_config(priv->cpg_mode);
 	if (!priv->cpg_pll_config->extal_div)
 		return -EINVAL;
 
-	priv->sscg = !(cpg_mode & BIT(12));
-
 	if (info->reg_layout == CLK_REG_LAYOUT_RCAR_GEN2_AND_GEN3) {
 		priv->info->status_regs = mstpsr;
 		priv->info->control_regs = smstpcr;
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.h b/drivers/clk/renesas/rcar-gen3-cpg.h
index 200e4adb906..894e3765495 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.h
+++ b/drivers/clk/renesas/rcar-gen3-cpg.h
@@ -132,7 +132,7 @@ struct gen3_clk_priv {
 	struct cpg_mssr_info	*info;
 	struct clk		clk_extal;
 	struct clk		clk_extalr;
-	bool			sscg;
+	u32			cpg_mode;
 	const struct rcar_gen3_cpg_pll_config *cpg_pll_config;
 };
 
-- 
2.39.2