From 295de9d0d063cc576c5c6322aeeda64d3579d9e5 Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Mon, 24 Oct 2022 12:22:59 +0200 Subject: [PATCH] clk: mediatek: mt8186-topckgen: Drop flags for main/univpll fixed factors The mainpll and univpll clocks are used as clock sources for multiple peripherals of different kind, some of which are critical (like AXIs); a rate change on any of these two will produce a rate change on many devices and that's likely to produce system instability if not done correctly: this is the reason why we have "fixed factor" clocks, used by MUX clocks to provide different rates based on PLL output dividers. Though, there's one fundamental issue that must be resolved somehow: When performing GPU DVFS, we get a rate request that will try to change the frequency of MAINPLL due to the CLK_TOP_MFG mux having clk26m, mfgpll (the GPU dedicated PLL), mainpll_d3, mainpll_d5 (fixed factor dividers) as possible parents. In order to solve that, there are two ways: 1. Add new "fake" mainpll_d3_fixed, mainpll_d5_fixed clocks, clones of mainpll_d3, mainpll_d5 clocks, for the only purpose of not declaring CLK_SET_RATE_PARENT; or 2. Simply drop said flag from the original dividers. After some careful validation, I cannot see anything calling a rate change request during runtime for MAINPLL, nor for UNIVPLL (which would, again, mean that we're reclocking lots of peripherals at once!), so it is safe *and sane* to simply remove the CLK_SET_RATE_PARENT flag to all of the main/univpll fixed factor divider clocks. Besides, if for any (doubtful) reason main/univpll rate change will be required in the future, it's still possible to call that on the PLL main clocks, so we're still covered anyway. Signed-off-by: AngeloGioacchino Del Regno Reviewed-by: Chen-Yu Tsai Link: https://lore.kernel.org/r/20221024102307.33722-3-angelogioacchino.delregno@collabora.com Signed-off-by: Chen-Yu Tsai --- drivers/clk/mediatek/clk-mt8186-topckgen.c | 62 +++++++++++----------- 1 file changed, 31 insertions(+), 31 deletions(-) diff --git a/drivers/clk/mediatek/clk-mt8186-topckgen.c b/drivers/clk/mediatek/clk-mt8186-topckgen.c index d7f2c4663c853..62b5ff4a57234 100644 --- a/drivers/clk/mediatek/clk-mt8186-topckgen.c +++ b/drivers/clk/mediatek/clk-mt8186-topckgen.c @@ -19,37 +19,37 @@ static const struct mtk_fixed_clk top_fixed_clks[] = { }; static const struct mtk_fixed_factor top_divs[] = { - FACTOR(CLK_TOP_MAINPLL_D2, "mainpll_d2", "mainpll", 1, 2), - FACTOR(CLK_TOP_MAINPLL_D2_D2, "mainpll_d2_d2", "mainpll_d2", 1, 2), - FACTOR(CLK_TOP_MAINPLL_D2_D4, "mainpll_d2_d4", "mainpll_d2", 1, 4), - FACTOR(CLK_TOP_MAINPLL_D2_D16, "mainpll_d2_d16", "mainpll_d2", 1, 16), - FACTOR(CLK_TOP_MAINPLL_D3, "mainpll_d3", "mainpll", 1, 3), - FACTOR(CLK_TOP_MAINPLL_D3_D2, "mainpll_d3_d2", "mainpll_d3", 1, 2), - FACTOR(CLK_TOP_MAINPLL_D3_D4, "mainpll_d3_d4", "mainpll_d3", 1, 4), - FACTOR(CLK_TOP_MAINPLL_D5, "mainpll_d5", "mainpll", 1, 5), - FACTOR(CLK_TOP_MAINPLL_D5_D2, "mainpll_d5_d2", "mainpll_d5", 1, 2), - FACTOR(CLK_TOP_MAINPLL_D5_D4, "mainpll_d5_d4", "mainpll_d5", 1, 4), - FACTOR(CLK_TOP_MAINPLL_D7, "mainpll_d7", "mainpll", 1, 7), - FACTOR(CLK_TOP_MAINPLL_D7_D2, "mainpll_d7_d2", "mainpll_d7", 1, 2), - FACTOR(CLK_TOP_MAINPLL_D7_D4, "mainpll_d7_d4", "mainpll_d7", 1, 4), - FACTOR(CLK_TOP_UNIVPLL, "univpll", "univ2pll", 1, 2), - FACTOR(CLK_TOP_UNIVPLL_D2, "univpll_d2", "univpll", 1, 2), - FACTOR(CLK_TOP_UNIVPLL_D2_D2, "univpll_d2_d2", "univpll_d2", 1, 2), - FACTOR(CLK_TOP_UNIVPLL_D2_D4, "univpll_d2_d4", "univpll_d2", 1, 4), - FACTOR(CLK_TOP_UNIVPLL_D3, "univpll_d3", "univpll", 1, 3), - FACTOR(CLK_TOP_UNIVPLL_D3_D2, "univpll_d3_d2", "univpll_d3", 1, 2), - FACTOR(CLK_TOP_UNIVPLL_D3_D4, "univpll_d3_d4", "univpll_d3", 1, 4), - FACTOR(CLK_TOP_UNIVPLL_D3_D8, "univpll_d3_d8", "univpll_d3", 1, 8), - FACTOR(CLK_TOP_UNIVPLL_D3_D32, "univpll_d3_d32", "univpll_d3", 1, 32), - FACTOR(CLK_TOP_UNIVPLL_D5, "univpll_d5", "univpll", 1, 5), - FACTOR(CLK_TOP_UNIVPLL_D5_D2, "univpll_d5_d2", "univpll_d5", 1, 2), - FACTOR(CLK_TOP_UNIVPLL_D5_D4, "univpll_d5_d4", "univpll_d5", 1, 4), - FACTOR(CLK_TOP_UNIVPLL_D7, "univpll_d7", "univpll", 1, 7), - FACTOR(CLK_TOP_UNIVPLL_192M, "univpll_192m", "univ2pll", 1, 13), - FACTOR(CLK_TOP_UNIVPLL_192M_D4, "univpll_192m_d4", "univpll_192m", 1, 4), - FACTOR(CLK_TOP_UNIVPLL_192M_D8, "univpll_192m_d8", "univpll_192m", 1, 8), - FACTOR(CLK_TOP_UNIVPLL_192M_D16, "univpll_192m_d16", "univpll_192m", 1, 16), - FACTOR(CLK_TOP_UNIVPLL_192M_D32, "univpll_192m_d32", "univpll_192m", 1, 32), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D2, "mainpll_d2", "mainpll", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D2_D2, "mainpll_d2_d2", "mainpll_d2", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D2_D4, "mainpll_d2_d4", "mainpll_d2", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D2_D16, "mainpll_d2_d16", "mainpll_d2", 1, 16, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D3, "mainpll_d3", "mainpll", 1, 3, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D3_D2, "mainpll_d3_d2", "mainpll_d3", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D3_D4, "mainpll_d3_d4", "mainpll_d3", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D5, "mainpll_d5", "mainpll", 1, 5, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D5_D2, "mainpll_d5_d2", "mainpll_d5", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D5_D4, "mainpll_d5_d4", "mainpll_d5", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D7, "mainpll_d7", "mainpll", 1, 7, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D7_D2, "mainpll_d7_d2", "mainpll_d7", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_MAINPLL_D7_D4, "mainpll_d7_d4", "mainpll_d7", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL, "univpll", "univ2pll", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D2, "univpll_d2", "univpll", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D2_D2, "univpll_d2_d2", "univpll_d2", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D2_D4, "univpll_d2_d4", "univpll_d2", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D3, "univpll_d3", "univpll", 1, 3, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D3_D2, "univpll_d3_d2", "univpll_d3", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D3_D4, "univpll_d3_d4", "univpll_d3", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D3_D8, "univpll_d3_d8", "univpll_d3", 1, 8, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D3_D32, "univpll_d3_d32", "univpll_d3", 1, 32, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D5, "univpll_d5", "univpll", 1, 5, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D5_D2, "univpll_d5_d2", "univpll_d5", 1, 2, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D5_D4, "univpll_d5_d4", "univpll_d5", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_D7, "univpll_d7", "univpll", 1, 7, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_192M, "univpll_192m", "univ2pll", 1, 13, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_192M_D4, "univpll_192m_d4", "univpll_192m", 1, 4, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_192M_D8, "univpll_192m_d8", "univpll_192m", 1, 8, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_192M_D16, "univpll_192m_d16", "univpll_192m", 1, 16, 0), + FACTOR_FLAGS(CLK_TOP_UNIVPLL_192M_D32, "univpll_192m_d32", "univpll_192m", 1, 32, 0), FACTOR(CLK_TOP_APLL1_D2, "apll1_d2", "apll1", 1, 2), FACTOR(CLK_TOP_APLL1_D4, "apll1_d4", "apll1", 1, 4), FACTOR(CLK_TOP_APLL1_D8, "apll1_d8", "apll1", 1, 8), -- 2.30.2