From 5c2602e5fcefa5a581ce20521552d7d446a3a9aa Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Tue, 14 Apr 2020 21:50:30 +0200 Subject: [PATCH] clk: meson: gxbb: Prepare the GPU clock tree to change at runtime The "mali_0" or "mali_1" clock trees should not be updated while the clock is running. Enforce this by setting CLK_SET_RATE_GATE on the "mali_0" and "mali_1" gates. This makes the CCF switch to the "mali_1" tree when "mali_0" is currently active and vice versa, which is exactly what the vendor driver does when updating the frequency of the mali clock. Also propagate set_rate requests from the gate to the divider and from the divider to the the mux so the GPU clock frequency can be updated at runtime (which will be required for GPU DVFS). Don't propagate rate changes to the mux parents because we don't want to change the MPLL clocks (these are reserved for audio). Signed-off-by: Martin Blumenstingl Signed-off-by: Jerome Brunet Acked-by: Neil Armstrong Link: https://lore.kernel.org/r/20200414195031.224021-2-martin.blumenstingl@googlemail.com --- drivers/clk/meson/gxbb.c | 40 ++++++++++++++++++++++------------------ 1 file changed, 22 insertions(+), 18 deletions(-) diff --git a/drivers/clk/meson/gxbb.c b/drivers/clk/meson/gxbb.c index 5fd6a57..0a68af6 100644 --- a/drivers/clk/meson/gxbb.c +++ b/drivers/clk/meson/gxbb.c @@ -957,7 +957,9 @@ static struct clk_regmap gxbb_sar_adc_clk = { /* * The MALI IP is clocked by two identical clocks (mali_0 and mali_1) - * muxed by a glitch-free switch. + * muxed by a glitch-free switch. The CCF can manage this glitch-free + * mux because it does top-to-bottom updates the each clock tree and + * switches to the "inactive" one when CLK_SET_RATE_GATE is set. */ static const struct clk_parent_data gxbb_mali_0_1_parent_data[] = { @@ -980,14 +982,15 @@ static struct clk_regmap gxbb_mali_0_sel = { .hw.init = &(struct clk_init_data){ .name = "mali_0_sel", .ops = &clk_regmap_mux_ops, - /* - * bits 10:9 selects from 8 possible parents: - * xtal, gp0_pll, mpll2, mpll1, fclk_div7, - * fclk_div4, fclk_div3, fclk_div5 - */ .parent_data = gxbb_mali_0_1_parent_data, .num_parents = 8, - .flags = CLK_SET_RATE_NO_REPARENT, + /* + * Don't request the parent to change the rate because + * all GPU frequencies can be derived from the fclk_* + * clocks and one special GP0_PLL setting. This is + * important because we need the MPLL clocks for audio. + */ + .flags = 0, }, }; @@ -1004,7 +1007,7 @@ static struct clk_regmap gxbb_mali_0_div = { &gxbb_mali_0_sel.hw }, .num_parents = 1, - .flags = CLK_SET_RATE_NO_REPARENT, + .flags = CLK_SET_RATE_PARENT, }, }; @@ -1020,7 +1023,7 @@ static struct clk_regmap gxbb_mali_0 = { &gxbb_mali_0_div.hw }, .num_parents = 1, - .flags = CLK_SET_RATE_PARENT, + .flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT, }, }; @@ -1033,14 +1036,15 @@ static struct clk_regmap gxbb_mali_1_sel = { .hw.init = &(struct clk_init_data){ .name = "mali_1_sel", .ops = &clk_regmap_mux_ops, - /* - * bits 10:9 selects from 8 possible parents: - * xtal, gp0_pll, mpll2, mpll1, fclk_div7, - * fclk_div4, fclk_div3, fclk_div5 - */ .parent_data = gxbb_mali_0_1_parent_data, .num_parents = 8, - .flags = CLK_SET_RATE_NO_REPARENT, + /* + * Don't request the parent to change the rate because + * all GPU frequencies can be derived from the fclk_* + * clocks and one special GP0_PLL setting. This is + * important because we need the MPLL clocks for audio. + */ + .flags = 0, }, }; @@ -1057,7 +1061,7 @@ static struct clk_regmap gxbb_mali_1_div = { &gxbb_mali_1_sel.hw }, .num_parents = 1, - .flags = CLK_SET_RATE_NO_REPARENT, + .flags = CLK_SET_RATE_PARENT, }, }; @@ -1073,7 +1077,7 @@ static struct clk_regmap gxbb_mali_1 = { &gxbb_mali_1_div.hw }, .num_parents = 1, - .flags = CLK_SET_RATE_PARENT, + .flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT, }, }; @@ -1093,7 +1097,7 @@ static struct clk_regmap gxbb_mali = { .ops = &clk_regmap_mux_ops, .parent_hws = gxbb_mali_parent_hws, .num_parents = 2, - .flags = CLK_SET_RATE_NO_REPARENT, + .flags = CLK_SET_RATE_PARENT, }, }; -- 2.7.4