From 61417aaa11402f8363a806a7167c46041f44465e Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Wed, 24 Jul 2019 16:59:04 +0200 Subject: [PATCH] drm/tegra: sor: Unify clock setup for eDP, HDMI and DP With the clocks modelled consistently across SoC generations, the clock setup for eDP, HDMI and DP can now be unified. Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/sor.c | 92 +++++++++++++++++++++++++++++++++++++++------ 1 file changed, 81 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c index fdbd76e..a245bbb 100644 --- a/drivers/gpu/drm/tegra/sor.c +++ b/drivers/gpu/drm/tegra/sor.c @@ -527,6 +527,14 @@ static const char * const tegra_clk_sor_pad_parents[2][2] = { { "pll_d2_out0", "pll_dp" }, }; +/* + * Implementing ->set_parent() here isn't really required because the parent + * will be explicitly selected in the driver code via the DP_CLK_SEL mux in + * the SOR_CLK_CNTRL register. This is primarily for compatibility with the + * Tegra186 and later SoC generations where the BPMP implements this clock + * and doesn't expose the mux via the common clock framework. + */ + static int tegra_clk_sor_pad_set_parent(struct clk_hw *hw, u8 index) { struct tegra_clk_sor_pad *pad = to_pad(hw); @@ -1987,10 +1995,36 @@ static void tegra_sor_edp_enable(struct drm_encoder *encoder) tegra_sor_writel(sor, 0x00000000, SOR_XBAR_POL); tegra_sor_writel(sor, value, SOR_XBAR_CTRL); - /* switch to DP parent clock */ - err = tegra_sor_set_parent_clock(sor, sor->clk_dp); - if (err < 0) - dev_err(sor->dev, "failed to set parent clock: %d\n", err); + /* + * Switch the pad clock to the DP clock. Note that we cannot actually + * do this because Tegra186 and later don't support clk_set_parent() + * on the sorX_pad_clkout clocks. We already do the equivalent above + * using the DP_CLK_SEL mux of the SOR_CLK_CNTRL register. + */ +#if 0 + err = clk_set_parent(sor->clk_pad, sor->clk_dp); + if (err < 0) { + dev_err(sor->dev, "failed to select pad parent clock: %d\n", + err); + return; + } +#endif + + /* switch the SOR clock to the pad clock */ + err = tegra_sor_set_parent_clock(sor, sor->clk_pad); + if (err < 0) { + dev_err(sor->dev, "failed to select SOR parent clock: %d\n", + err); + return; + } + + /* switch the output clock to the parent pixel clock */ + err = clk_set_parent(sor->clk, sor->clk_parent); + if (err < 0) { + dev_err(sor->dev, "failed to select output parent clock: %d\n", + err); + return; + } /* use DP-A protocol */ value = tegra_sor_readl(sor, SOR_STATE1); @@ -2661,16 +2695,34 @@ static void tegra_sor_hdmi_enable(struct drm_encoder *encoder) tegra_sor_writel(sor, 0x00000000, SOR_XBAR_POL); tegra_sor_writel(sor, value, SOR_XBAR_CTRL); - /* switch to parent clock */ - err = clk_set_parent(sor->clk, sor->clk_parent); + /* + * Switch the pad clock to the DP clock. Note that we cannot actually + * do this because Tegra186 and later don't support clk_set_parent() + * on the sorX_pad_clkout clocks. We already do the equivalent above + * using the DP_CLK_SEL mux of the SOR_CLK_CNTRL register. + */ +#if 0 + err = clk_set_parent(sor->clk_pad, sor->clk_dp); if (err < 0) { - dev_err(sor->dev, "failed to set parent clock: %d\n", err); + dev_err(sor->dev, "failed to select pad parent clock: %d\n", + err); return; } +#endif + /* switch the SOR clock to the pad clock */ err = tegra_sor_set_parent_clock(sor, sor->clk_pad); if (err < 0) { - dev_err(sor->dev, "failed to set pad clock: %d\n", err); + dev_err(sor->dev, "failed to select SOR parent clock: %d\n", + err); + return; + } + + /* switch the output clock to the parent pixel clock */ + err = clk_set_parent(sor->clk, sor->clk_parent); + if (err < 0) { + dev_err(sor->dev, "failed to select output parent clock: %d\n", + err); return; } @@ -3061,16 +3113,34 @@ static void tegra_sor_dp_enable(struct drm_encoder *encoder) tegra_sor_writel(sor, 0x00000000, SOR_XBAR_POL); tegra_sor_writel(sor, value, SOR_XBAR_CTRL); - /* switch to DP parent clock */ + /* + * Switch the pad clock to the DP clock. Note that we cannot actually + * do this because Tegra186 and later don't support clk_set_parent() + * on the sorX_pad_clkout clocks. We already do the equivalent above + * using the DP_CLK_SEL mux of the SOR_CLK_CNTRL register. + */ +#if 0 + err = clk_set_parent(sor->clk_pad, sor->clk_parent); + if (err < 0) { + dev_err(sor->dev, "failed to select pad parent clock: %d\n", + err); + return; + } +#endif + + /* switch the SOR clock to the pad clock */ err = tegra_sor_set_parent_clock(sor, sor->clk_pad); if (err < 0) { - dev_err(sor->dev, "failed to switch to pad clock: %d\n", err); + dev_err(sor->dev, "failed to select SOR parent clock: %d\n", + err); return; } + /* switch the output clock to the parent pixel clock */ err = clk_set_parent(sor->clk, sor->clk_parent); if (err < 0) { - dev_err(sor->dev, "failed to switch to parent clock: %d\n", err); + dev_err(sor->dev, "failed to select output parent clock: %d\n", + err); return; } -- 2.7.4