[PATCH RFC 3/3] clk: meson: t7: Model PLL pre-divider as a divider clock

Jian Hu via B4 Relay devnull+jian.hu.amlogic.com at kernel.org
Wed Sep 23 04:14:49 PDT 2026


From: Jian Hu <jian.hu at amlogic.com>

Replace the dedicated PLL pre-divider with a standalone
divider clock. The PLL DCO now takes the pre-divider clock
as its parent instead of the input clock directly.

Signed-off-by: Jian Hu <jian.hu at amlogic.com>
---
 drivers/clk/meson/t7-pll.c | 183 ++++++++++++++++++++++++++++++++++-----------
 1 file changed, 141 insertions(+), 42 deletions(-)

diff --git a/drivers/clk/meson/t7-pll.c b/drivers/clk/meson/t7-pll.c
index 0a622f45fa36..049f0c879c45 100644
--- a/drivers/clk/meson/t7-pll.c
+++ b/drivers/clk/meson/t7-pll.c
@@ -71,6 +71,34 @@
 #define MCLK_PLL_CNTL4		0x10
 #define MCLK_PLL_STS		0x14
 
+static const struct clk_div_table t7_prediv_div_table[] = {
+	{ .val = 1, .div = 1 },
+	{ /* sentinel */ }
+};
+
+static struct clk_regmap t7_gp0_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = GP0PLL_CTRL0,
+		.shift = 10,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/*
+		 * The hardware reset value is 0. Allow it during clock registration
+		 * to avoid a warning from the common divider code.
+		 * set_rate() will program the valid divider value (1).
+		 */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "gp0_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static const struct pll_mult_range t7_media_pll_mult_range = {
 	.min = 125,
 	.max = 250,
@@ -97,11 +125,6 @@ static struct clk_regmap t7_gp0_pll_dco = {
 			.shift   = 0,
 			.width   = 8,
 		},
-		.n = {
-			.reg_off = GP0PLL_CTRL0,
-			.shift   = 10,
-			.width   = 5,
-		},
 		.l = {
 			.reg_off = GP0PLL_STS,
 			.shift   = 31,
@@ -119,8 +142,8 @@ static struct clk_regmap t7_gp0_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "gp0_pll_dco",
 		.ops = &meson_clk_pll_ops,
-		.parent_data = &(const struct clk_parent_data) {
-			.fw_name = "in0",
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_gp0_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -159,6 +182,25 @@ static const struct reg_sequence t7_gp1_init_regs[] = {
 	{ .reg = GP1PLL_CTRL3,  .def = 0x00000000 },
 };
 
+static struct clk_regmap t7_gp1_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = GP1PLL_CTRL0,
+		.shift = 16,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/* Same rationale as gp0_prediv. */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "gp1_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static struct clk_regmap t7_gp1_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -171,11 +213,6 @@ static struct clk_regmap t7_gp1_pll_dco = {
 			.shift   = 0,
 			.width   = 8,
 		},
-		.n = {
-			.reg_off = GP1PLL_CTRL0,
-			.shift   = 16,
-			.width   = 5,
-		},
 		.l = {
 			.reg_off = GP1PLL_STS,
 			.shift   = 31,
@@ -193,8 +230,8 @@ static struct clk_regmap t7_gp1_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "gp1_pll_dco",
 		.ops = &meson_clk_pll_ops,
-		.parent_data = &(const struct clk_parent_data) {
-			.fw_name = "in0",
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_gp1_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -227,6 +264,25 @@ static const struct reg_sequence t7_hifi_init_regs[] = {
 	{ .reg = HIFIPLL_CTRL6, .def = 0x56540000 }
 };
 
+static struct clk_regmap t7_hifi_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = HIFIPLL_CTRL0,
+		.shift = 10,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/* Same rationale as gp0_prediv. */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "hifi_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static struct clk_regmap t7_hifi_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -239,11 +295,6 @@ static struct clk_regmap t7_hifi_pll_dco = {
 			.shift   = 0,
 			.width   = 8,
 		},
-		.n = {
-			.reg_off = HIFIPLL_CTRL0,
-			.shift   = 10,
-			.width   = 5,
-		},
 		.frac = {
 			.reg_off = HIFIPLL_CTRL1,
 			.shift   = 0,
@@ -267,8 +318,8 @@ static struct clk_regmap t7_hifi_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "hifi_pll_dco",
 		.ops = &meson_clk_pll_ops,
-		.parent_data = &(const struct clk_parent_data) {
-			.fw_name = "in0",
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_hifi_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -312,6 +363,25 @@ static const struct reg_sequence t7_pcie_pll_init_regs[] = {
 	{ .reg = PCIEPLL_CTRL2,	.def = 0x00001000 }
 };
 
+static struct clk_regmap t7_pcie_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = PCIEPLL_CTRL0,
+		.shift = 10,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/* Same rationale as gp0_prediv. */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "pcie_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static struct clk_regmap t7_pcie_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -324,11 +394,6 @@ static struct clk_regmap t7_pcie_pll_dco = {
 			.shift   = 0,
 			.width   = 8,
 		},
-		.n = {
-			.reg_off = PCIEPLL_CTRL0,
-			.shift   = 10,
-			.width   = 5,
-		},
 		.l = {
 			.reg_off = PCIEPLL_CTRL0,
 			.shift   = 31,
@@ -345,8 +410,8 @@ static struct clk_regmap t7_pcie_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "pcie_pll_dco",
 		.ops = &meson_clk_pcie_pll_ops,
-		.parent_data = &(const struct clk_parent_data) {
-			.fw_name = "in0",
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_pcie_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -633,6 +698,25 @@ static const struct reg_sequence t7_hdmi_init_regs[] = {
 	{ .reg = HDMIPLL_CTRL6, .def = 0x56540000 }
 };
 
+static struct clk_regmap t7_hdmi_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = HDMIPLL_CTRL0,
+		.shift = 10,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/* Same rationale as gp0_prediv. */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "hdmi_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static struct clk_regmap t7_hdmi_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -645,11 +729,6 @@ static struct clk_regmap t7_hdmi_pll_dco = {
 			.shift   = 0,
 			.width   = 9,
 		},
-		.n = {
-			.reg_off = HDMIPLL_CTRL0,
-			.shift   = 10,
-			.width   = 5,
-		},
 		.l = {
 			.reg_off = HDMIPLL_CTRL0,
 			.shift   = 31,
@@ -667,8 +746,8 @@ static struct clk_regmap t7_hdmi_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "hdmi_pll_dco",
 		.ops = &meson_clk_pll_ops,
-		.parent_data = (const struct clk_parent_data []) {
-			{ .fw_name = "in0", }
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_hdmi_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -722,6 +801,25 @@ static const struct reg_sequence t7_mclk_init_regs[] = {
 	{ .reg = MCLK_PLL_CNTL4, .def = 0x00180303 },
 };
 
+static struct clk_regmap t7_mclk_prediv = {
+	.data = &(struct clk_regmap_div_data){
+		.offset = MCLK_PLL_CNTL0,
+		.shift = 16,
+		.width = 5,
+		.table = t7_prediv_div_table,
+		/* Same rationale as gp0_prediv. */
+		.flags = CLK_DIVIDER_ALLOW_ZERO,
+	},
+	.hw.init = &(struct clk_init_data) {
+		.name = "mclk_prediv",
+		.ops = &clk_regmap_divider_ops,
+		.parent_data = &(const struct clk_parent_data) {
+			.fw_name = "in0",
+		},
+		.num_parents = 1,
+	},
+};
+
 static struct clk_regmap t7_mclk_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -734,11 +832,6 @@ static struct clk_regmap t7_mclk_pll_dco = {
 			.shift   = 0,
 			.width   = 8,
 		},
-		.n = {
-			.reg_off = MCLK_PLL_CNTL0,
-			.shift   = 16,
-			.width   = 5,
-		},
 		.l = {
 			.reg_off = MCLK_PLL_CNTL0,
 			.shift   = 31,
@@ -761,8 +854,8 @@ static struct clk_regmap t7_mclk_pll_dco = {
 	.hw.init = &(struct clk_init_data){
 		.name = "mclk_pll_dco",
 		.ops = &meson_clk_pll_ops,
-		.parent_data = &(const struct clk_parent_data) {
-			.fw_name = "in0",
+		.parent_hws = (const struct clk_hw *[]) {
+			&t7_mclk_prediv.hw
 		},
 		.num_parents = 1,
 	},
@@ -939,21 +1032,25 @@ static struct clk_regmap t7_mclk_1 = {
 };
 
 static struct clk_hw *t7_gp0_hw_clks[] = {
+	[CLKID_GP0_PREDIV]		= &t7_gp0_prediv.hw,
 	[CLKID_GP0_PLL_DCO]		= &t7_gp0_pll_dco.hw,
 	[CLKID_GP0_PLL]			= &t7_gp0_pll.hw,
 };
 
 static struct clk_hw *t7_gp1_hw_clks[] = {
+	[CLKID_GP1_PREDIV]		= &t7_gp1_prediv.hw,
 	[CLKID_GP1_PLL_DCO]		= &t7_gp1_pll_dco.hw,
 	[CLKID_GP1_PLL]			= &t7_gp1_pll.hw,
 };
 
 static struct clk_hw *t7_hifi_hw_clks[] = {
+	[CLKID_HIFI_PREDIV]		= &t7_hifi_prediv.hw,
 	[CLKID_HIFI_PLL_DCO]		= &t7_hifi_pll_dco.hw,
 	[CLKID_HIFI_PLL]		= &t7_hifi_pll.hw,
 };
 
 static struct clk_hw *t7_pcie_hw_clks[] = {
+	[CLKID_PCIE_PREDIV]		= &t7_pcie_prediv.hw,
 	[CLKID_PCIE_PLL_DCO]		= &t7_pcie_pll_dco.hw,
 	[CLKID_PCIE_PLL_DCO_DIV2]	= &t7_pcie_pll_dco_div2.hw,
 	[CLKID_PCIE_PLL_OD]		= &t7_pcie_pll_od.hw,
@@ -973,12 +1070,14 @@ static struct clk_hw *t7_mpll_hw_clks[] = {
 };
 
 static struct clk_hw *t7_hdmi_hw_clks[] = {
+	[CLKID_HDMI_PREDIV]		= &t7_hdmi_prediv.hw,
 	[CLKID_HDMI_PLL_DCO]		= &t7_hdmi_pll_dco.hw,
 	[CLKID_HDMI_PLL_OD]		= &t7_hdmi_pll_od.hw,
 	[CLKID_HDMI_PLL]		= &t7_hdmi_pll.hw,
 };
 
 static struct clk_hw *t7_mclk_hw_clks[] = {
+	[CLKID_MCLK_PREDIV]		= &t7_mclk_prediv.hw,
 	[CLKID_MCLK_PLL_DCO]		= &t7_mclk_pll_dco.hw,
 	[CLKID_MCLK_PRE]		= &t7_mclk_pre_od.hw,
 	[CLKID_MCLK_PLL]		= &t7_mclk_pll.hw,

-- 
2.47.1





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