[U-Boot] [PATCH 07/19] imx: mx6: lcdif: gate clock before changing mux

Peng Fan peng.fan at nxp.com
Thu Nov 24 07:47:49 CET 2016


The mux for the lcd clock is not glitchless,
so need to first gate the clock before changing the mux.

Signed-off-by: Peng Fan <peng.fan at nxp.com>
Cc: Stefano Babic <sbabic at denx.de>
---
 arch/arm/cpu/armv7/mx6/clock.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/cpu/armv7/mx6/clock.c b/arch/arm/cpu/armv7/mx6/clock.c
index 8ab07b6..644b9d7 100644
--- a/arch/arm/cpu/armv7/mx6/clock.c
+++ b/arch/arm/cpu/armv7/mx6/clock.c
@@ -771,6 +771,16 @@ int enable_lcdif_clock(u32 base_addr)
 		return 0;
 	}
 
+	/* Gate LCDIF clock first */
+	reg = readl(&imx_ccm->CCGR3);
+	reg &= ~lcdif_ccgr3_mask;
+	writel(reg, &imx_ccm->CCGR3);
+
+	reg = readl(&imx_ccm->CCGR2);
+	reg &= ~MXC_CCM_CCGR2_LCD_MASK;
+	writel(reg, &imx_ccm->CCGR2);
+
+	/* Select pre-mux */
 	reg = readl(&imx_ccm->cscdr2);
 	reg &= ~lcdif_clk_sel_mask;
 	writel(reg, &imx_ccm->cscdr2);
-- 
2.6.2



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