[PATCH 7/8] clk: imx6: retain early UART clocks during kernel init
From: l.stach@pengutronix.de (Lucas Stach)
Date: 2015-08-27 16:39:20
Also in:
linux-clk
Subsystem:
common clk framework, nxp i.mx clock drivers, the rest · Maintainers:
Michael Turquette, Stephen Boyd, Abel Vesa, Linus Torvalds
Make sure to keep UART clocks enabled during kernel init if earlyprintk or earlycon are active. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> --- drivers/clk/imx/clk-imx6q.c | 12 ++++++++++++ drivers/clk/imx/clk-imx6sl.c | 12 ++++++++++++ drivers/clk/imx/clk-imx6sx.c | 12 ++++++++++++ 3 files changed, 36 insertions(+)
diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
index d046f8e43de8..af6a6517b26c 100644
--- a/drivers/clk/imx/clk-imx6q.c
+++ b/drivers/clk/imx/clk-imx6q.c@@ -130,6 +130,12 @@ static inline int clk_on_imx6dl(void) return of_machine_is_compatible("fsl,imx6dl"); } +static void __init imx6q_uart_disable_cb(void) +{ + clk_disable_unprepare(clk[IMX6QDL_CLK_UART_IPG]); + clk_disable_unprepare(clk[IMX6QDL_CLK_UART_SERIAL]); +} + static void __init imx6q_clocks_init(struct device_node *ccm_node) { struct device_node *np;
@@ -534,5 +540,11 @@ 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[IMX6QDL_CLK_LVDS1_SEL], clk[IMX6QDL_CLK_SATA_REF_100M]); + + if (imx_clk_keep_uart()) { + clk_prepare_enable(clk[IMX6QDL_CLK_UART_IPG]); + clk_prepare_enable(clk[IMX6QDL_CLK_UART_SERIAL]); + imx_clk_set_uart_disable_callback(imx6q_uart_disable_cb); + } } CLK_OF_DECLARE(imx6q, "fsl,imx6q-ccm", imx6q_clocks_init);
diff --git a/drivers/clk/imx/clk-imx6sl.c b/drivers/clk/imx/clk-imx6sl.c
index a0d4cf26cfa9..737a9a84f201 100644
--- a/drivers/clk/imx/clk-imx6sl.c
+++ b/drivers/clk/imx/clk-imx6sl.c@@ -184,6 +184,12 @@ void imx6sl_set_wait_clk(bool enter) imx6sl_enable_pll_arm(false); } +static void __init imx6sl_uart_disable_cb(void) +{ + clk_disable_unprepare(clks[IMX6SL_CLK_UART]); + clk_disable_unprepare(clks[IMX6SL_CLK_UART_SERIAL]); +} + static void __init imx6sl_clocks_init(struct device_node *ccm_node) { struct device_node *np;
@@ -439,5 +445,11 @@ static void __init imx6sl_clocks_init(struct device_node *ccm_node) clk_set_parent(clks[IMX6SL_CLK_LCDIF_AXI_SEL], clks[IMX6SL_CLK_PLL2_PFD2]); + + if (imx_clk_keep_uart()) { + clk_prepare_enable(clks[IMX6SL_CLK_UART]); + clk_prepare_enable(clks[IMX6SL_CLK_UART_SERIAL]); + imx_clk_set_uart_disable_callback(imx6sl_uart_disable_cb); + } } CLK_OF_DECLARE(imx6sl, "fsl,imx6sl-ccm", imx6sl_clocks_init);
diff --git a/drivers/clk/imx/clk-imx6sx.c b/drivers/clk/imx/clk-imx6sx.c
index 5b95c2c2bf52..ec14235659cc 100644
--- a/drivers/clk/imx/clk-imx6sx.c
+++ b/drivers/clk/imx/clk-imx6sx.c@@ -135,6 +135,12 @@ static u32 share_count_ssi1; static u32 share_count_ssi2; static u32 share_count_ssi3; +static void __init imx6sx_uart_disable_cb(void) +{ + clk_disable_unprepare(clks[IMX6SX_CLK_UART_IPG]); + clk_disable_unprepare(clks[IMX6SX_CLK_UART_SERIAL]); +} + static void __init imx6sx_clocks_init(struct device_node *ccm_node) { struct device_node *np;
@@ -557,5 +563,11 @@ static void __init imx6sx_clocks_init(struct device_node *ccm_node) clk_set_parent(clks[IMX6SX_CLK_QSPI1_SEL], clks[IMX6SX_CLK_PLL2_BUS]); clk_set_parent(clks[IMX6SX_CLK_QSPI2_SEL], clks[IMX6SX_CLK_PLL2_BUS]); + + if (imx_clk_keep_uart()) { + clk_prepare_enable(clks[IMX6SX_CLK_UART_IPG]); + clk_prepare_enable(clks[IMX6SX_CLK_UART_SERIAL]); + imx_clk_set_uart_disable_callback(imx6sx_uart_disable_cb); + } } CLK_OF_DECLARE(imx6sx, "fsl,imx6sx-ccm", imx6sx_clocks_init);
--
2.5.0