From: Lucas Stach Date: Thu, 17 Jul 2014 10:20:14 +0000 (+0200) Subject: ARM: clk-imx6q: parent lvds_sel input from upstream clock gates X-Git-Tag: firefly_0821_release~176^2~3592^2~1^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=03e97220b99b8b691ea5b130b7b4c135c9662792;p=firefly-linux-kernel-4.4.55.git ARM: clk-imx6q: parent lvds_sel input from upstream clock gates The i.MX6 reference manual doesn't make a clear distinction between the fixed clock divider and the enable gate for the pcie and sata reference clocks. This lead to the lvds mux inputs in the imx6q clk driver to be parented from the ref clock (which is the divider) instead of the actual gate, which in turn prevents the upstream clock to actually be enabled when lvds clk out is active. This fixes a hard machine hang regression in kernel 3.16 for boards where only pcie is active but no sata, as with this kernel version the imx6-pcie driver is no longer enabling the upstream clock directly but only lvds clk out. Reported-by: Arne Ruhnau Signed-off-by: Lucas Stach Tested-by: Arne Ruhnau Signed-off-by: Shawn Guo --- diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c index 8e795dea02ec..8556c787e59c 100644 --- a/arch/arm/mach-imx/clk-imx6q.c +++ b/arch/arm/mach-imx/clk-imx6q.c @@ -70,7 +70,7 @@ static const char *cko_sels[] = { "cko1", "cko2", }; static const char *lvds_sels[] = { "dummy", "dummy", "dummy", "dummy", "dummy", "dummy", "pll4_audio", "pll5_video", "pll8_mlb", "enet_ref", - "pcie_ref", "sata_ref", + "pcie_ref_125m", "sata_ref_100m", }; enum mx6q_clks { @@ -491,7 +491,7 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node) /* All existing boards with PCIe use LVDS1 */ if (IS_ENABLED(CONFIG_PCI_IMX6)) - clk_set_parent(clk[lvds1_sel], clk[sata_ref]); + clk_set_parent(clk[lvds1_sel], clk[sata_ref_100m]); /* Set initial power mode */ imx6q_set_lpm(WAIT_CLOCKED);