From mboxrd@z Thu Jan 1 00:00:00 1970 From: b20788@freescale.com (Anson Huang) Date: Wed, 22 Jan 2014 15:14:47 +0800 Subject: [PATCH V3] ARM: imx: add always-on clock array for i.mx6sl to maintain correct usecount Message-ID: <1390374887-22833-1-git-send-email-b20788@freescale.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org IPG, ARM and MMDC's clock should be enabled during kernel boot up, so we need to maintain their usecount, otherwise, they may be disabled unexpectedly if their children's clock are turned off, and caused their parent PLLs also get disabled, which is incorrect. Signed-off-by: Anson Huang --- arch/arm/mach-imx/clk-imx6sl.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/arm/mach-imx/clk-imx6sl.c b/arch/arm/mach-imx/clk-imx6sl.c index 78f3bd6..04e9f1c 100644 --- a/arch/arm/mach-imx/clk-imx6sl.c +++ b/arch/arm/mach-imx/clk-imx6sl.c @@ -66,6 +66,10 @@ static struct clk_div_table video_div_table[] = { static struct clk *clks[IMX6SL_CLK_END]; static struct clk_onecell_data clk_data; +static const u32 clks_init_on[] __initconst = { + IMX6SL_CLK_IPG, IMX6SL_CLK_ARM, IMX6SL_CLK_MMDC_ROOT, +}; + /* * ERR005311 CCM: After exit from WAIT mode, unwanted interrupt(s) taken * during WAIT mode entry process could cause cache memory @@ -291,6 +295,13 @@ static void __init imx6sl_clocks_init(struct device_node *ccm_node) pr_warn("%s: failed to set AHB clock rate %d!\n", __func__, ret); + /* + * Make sure those always on clocks are enabled to maintain the correct + * usecount and enabling/disabling of parent PLLs. + */ + for (i = 0; i < ARRAY_SIZE(clks_init_on); i++) + clk_prepare_enable(clks[clks_init_on[i]]); + if (IS_ENABLED(CONFIG_USB_MXS_PHY)) { clk_prepare_enable(clks[IMX6SL_CLK_USBPHY1_GATE]); clk_prepare_enable(clks[IMX6SL_CLK_USBPHY2_GATE]); -- 1.7.9.5