[PATCH] clk: renesas: r8a779h0: Drop CLK_PLL2_DIV2 to clarify ZCn clocks

[Marek Vasut]

From: Geert Uytterhoeven <geert+renesas at glider.be>

Early revisions of the R-Car V4M Series Hardware User’s Manual
contained an incorrect formula for the CPU core clocks:

    ZCnφ = (PLL2VCO x 1/2) x mult/32

Dang-san fixed this by using CLK_PLL2_DIV2 instead of CLK_PLL2 as the
parent clock.

In Rev.0.70 of the documentation, the formula was corrected to:

    ZCnφ = (PLL2VCO x 1/4) x mult/32

As the CPG Block Diagram now shows a separate 1/4 post-divider for PLL2,
the use of CLK_PLL2_DIV2 is a recurring source of confusion.  Hence get
rid of CLK_PLL2_DIV2, and include the proper 1/4 post-divider in the
invocation of the DEF_GEN4_Z() macro, like is done on other R-Car Gen4
(and Gen3) SoCs.

Ported from Linux commit
92850bed9d4d ("clk: renesas: r8a779h0: Drop CLK_PLL2_DIV2 to clarify ZCn clocks")

Reported-by: Vinh Nguyen <vinh.nguyen.xz at renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
Link: https://lore.kernel.org/0d2789cac2bf306145fe0bbf269c2da5942bb68f.1728377724.git.geert+renesas@glider.be
Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
Cc: Geert Uytterhoeven <geert+renesas at glider.be>
Cc: Hai Pham <hai.pham.ud at renesas.com>
Cc: Lukasz Majewski <lukma at denx.de>
Cc: Nobuhiro Iwamatsu <iwamatsu at nigauri.org>
Cc: Sean Anderson <seanga2 at gmail.com>
Cc: Tom Rini <trini at konsulko.com>
Cc: u-boot at lists.denx.de
---
 drivers/clk/renesas/r8a779h0-cpg-mssr.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/clk/renesas/r8a779h0-cpg-mssr.c b/drivers/clk/renesas/r8a779h0-cpg-mssr.c
index 2e98e262fb0..70fa8ff2871 100644
--- a/drivers/clk/renesas/r8a779h0-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a779h0-cpg-mssr.c
@@ -39,7 +39,6 @@ enum clk_ids {
 	CLK_PLL6,
 	CLK_PLL7,
 	CLK_PLL1_DIV2,
-	CLK_PLL2_DIV2,
 	CLK_PLL3_DIV2,
 	CLK_PLL4_DIV2,
 	CLK_PLL4_DIV5,
@@ -82,7 +81,6 @@ static const struct cpg_core_clk r8a779h0_core_clks[] = {
 	DEF_BASE(".pll7", CLK_PLL7,	CLK_TYPE_GEN4_PLL7,	CLK_MAIN),
 
 	DEF_FIXED(".pll1_div2",	CLK_PLL1_DIV2,	CLK_PLL1,	2, 1),
-	DEF_FIXED(".pll2_div2",	CLK_PLL2_DIV2,	CLK_PLL2,	2, 1),
 	DEF_FIXED(".pll3_div2",	CLK_PLL3_DIV2,	CLK_PLL3,	2, 1),
 	DEF_FIXED(".pll4_div2",	CLK_PLL4_DIV2,	CLK_PLL4,	2, 1),
 	DEF_FIXED(".pll4_div5",	CLK_PLL4_DIV5,	CLK_PLL4,	5, 1),
@@ -106,10 +104,10 @@ static const struct cpg_core_clk r8a779h0_core_clks[] = {
 	DEF_RATE(".oco",	CLK_OCO,	32768),
 
 	/* Core Clock Outputs */
-	DEF_GEN4_Z("zc0",	R8A779H0_CLK_ZC0,	CLK_TYPE_GEN4_Z,	CLK_PLL2_DIV2,	2, 0),
-	DEF_GEN4_Z("zc1",	R8A779H0_CLK_ZC1,	CLK_TYPE_GEN4_Z,	CLK_PLL2_DIV2,	2, 8),
-	DEF_GEN4_Z("zc2",	R8A779H0_CLK_ZC2,	CLK_TYPE_GEN4_Z,	CLK_PLL2_DIV2,	2, 32),
-	DEF_GEN4_Z("zc3",	R8A779H0_CLK_ZC3,	CLK_TYPE_GEN4_Z,	CLK_PLL2_DIV2,	2, 40),
+	DEF_GEN4_Z("zc0",	R8A779H0_CLK_ZC0,	CLK_TYPE_GEN4_Z,	CLK_PLL2,	4, 0),
+	DEF_GEN4_Z("zc1",	R8A779H0_CLK_ZC1,	CLK_TYPE_GEN4_Z,	CLK_PLL2,	4, 8),
+	DEF_GEN4_Z("zc2",	R8A779H0_CLK_ZC2,	CLK_TYPE_GEN4_Z,	CLK_PLL2,	4, 32),
+	DEF_GEN4_Z("zc3",	R8A779H0_CLK_ZC3,	CLK_TYPE_GEN4_Z,	CLK_PLL2,	4, 40),
 	DEF_FIXED("s0d2",	R8A779H0_CLK_S0D2,	CLK_S0,		2, 1),
 	DEF_FIXED("s0d3",	R8A779H0_CLK_S0D3,	CLK_S0,		3, 1),
 	DEF_FIXED("s0d4",	R8A779H0_CLK_S0D4,	CLK_S0,		4, 1),
-- 
2.45.2