On Mon, Sep 19, 2016 at 11:07:11AM +0200, Lucas Stach wrote:

quoted

quoted

diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
index 64c243173395..751c3e7d5843 100644
--- a/drivers/clk/imx/clk-imx6q.c
+++ b/drivers/clk/imx/clk-imx6q.c

@@ -633,6 +633,24 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
 	if (IS_ENABLED(CONFIG_PCI_IMX6))
 		clk_set_parent(clk[IMX6QDL_CLK_LVDS1_SEL], clk[IMX6QDL_CLK_SATA_REF_100M]);
 
+	/*
+	 * Initialize the GPU clock muxes, so that the maximum specified clock
+	 * rates for the respective SoC are not exceeded.
+	 */
+	if (clk_on_imx6dl()) {
+		clk_set_parent(clk[IMX6QDL_CLK_GPU3D_CORE_SEL],
+		               clk[IMX6QDL_CLK_PLL2_PFD1_594M]);
+		clk_set_parent(clk[IMX6QDL_CLK_GPU2D_CORE_SEL],
+		               clk[IMX6QDL_CLK_PLL2_PFD1_594M]);
+	} else if (clk_on_imx6q()) {
+		clk_set_parent(clk[IMX6QDL_CLK_GPU3D_CORE_SEL],
+		               clk[IMX6QDL_CLK_MMDC_CH0_AXI]);
+		clk_set_parent(clk[IMX6QDL_CLK_GPU3D_SHADER_SEL],
+		               clk[IMX6QDL_CLK_PLL2_PFD1_594M]);
+		clk_set_parent(clk[IMX6QDL_CLK_GPU2D_CORE_SEL],
+		               clk[IMX6QDL_CLK_PLL3_USB_OTG]);
+	}
+

Can we handle these with assigned-clock-parents from device tree?

No, we want to get rid of the GPU overclocking even with old DTs. DT
stability rules and all that...

Fair point.  For both patches,

Acked-by: Shawn Guo <shawnguo@kernel.org>