[PATCH 3/6] clk: meson: meson8b: Add the HDMI PLL M/N parameters

Martin Blumenstingl martin.blumenstingl at googlemail.com
Tue Jul 13 16:25:07 PDT 2021


The 3.10 vendor kernel uses only specific HDMI PLL M/N parameter
combinations. The PLL won't lock for values smaller than 50 if the
internal doubling (which is yet unknown how to use it) is disabled.
However, when this doubling is enabled then the values smaller than 50
will lock just fine. The only restriction for values greater than 50 is
that the resulting frequency must not exceed the 3.0GHz limit.

These values are taken from the endlessm 3.10 kernel which includes
additional M/N combinations for some VESA and 75Hz display modes.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>
---
 drivers/clk/meson/meson8b.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c
index 9ccffbfe44e5..8f29d26ed726 100644
--- a/drivers/clk/meson/meson8b.c
+++ b/drivers/clk/meson/meson8b.c
@@ -118,6 +118,27 @@ static struct clk_regmap meson8b_fixed_pll = {
 	},
 };
 
+static const struct pll_params_table hdmi_pll_params_table[] = {
+	PLL_PARAMS(40, 1),
+	PLL_PARAMS(42, 1),
+	PLL_PARAMS(44, 1),
+	PLL_PARAMS(45, 1),
+	PLL_PARAMS(49, 1),
+	PLL_PARAMS(52, 1),
+	PLL_PARAMS(54, 1),
+	PLL_PARAMS(56, 1),
+	PLL_PARAMS(59, 1),
+	PLL_PARAMS(60, 1),
+	PLL_PARAMS(61, 1),
+	PLL_PARAMS(62, 1),
+	PLL_PARAMS(64, 1),
+	PLL_PARAMS(66, 1),
+	PLL_PARAMS(68, 1),
+	PLL_PARAMS(71, 1),
+	PLL_PARAMS(82, 1),
+	{ /* sentinel */ }
+};
+
 static struct clk_regmap meson8b_hdmi_pll_dco = {
 	.data = &(struct meson_clk_pll_data){
 		.en = {
@@ -150,6 +171,7 @@ static struct clk_regmap meson8b_hdmi_pll_dco = {
 			.shift   = 29,
 			.width   = 1,
 		},
+		.table = hdmi_pll_params_table,
 	},
 	.hw.init = &(struct clk_init_data){
 		/* sometimes also called "HPLL" or "HPLL PLL" */
-- 
2.32.0




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