imx: mx6sx: select OSC as uart's clk parent

As M4 is sourcing UART clk from OSC, to make UART work
when M4 is enabled, need to select OSC as clk parent,
24M OSC is enough for debug UART in uboot.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>

diff --git a/arch/arm/mach-imx/mx6/soc.c b/arch/arm/mach-imx/mx6/soc.c
index e87a21513e0e53a228216cb2ec6c1970f8dd430d..48eaa849218c02cfc30968d19ca0722d88310de3 100644 (file)
--- a/arch/arm/mach-imx/mx6/soc.c
+++ b/arch/arm/mach-imx/mx6/soc.c
@@ -379,6 +379,8 @@ static void set_preclk_from_osc(void)
 
 int arch_cpu_init(void)
 {
+       struct mxc_ccm_reg *ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
+
        init_aips();
 
        /* Need to clear MMDC_CHx_MASK to make warm reset work. */
@@ -448,6 +450,9 @@ int arch_cpu_init(void)
 
        imx_set_wdog_powerdown(false); /* Disable PDE bit of WMCR register */
 
+       if (is_mx6sx())
+               setbits_le32(&ccm->cscdr1, MXC_CCM_CSCDR1_UART_CLK_SEL);
+
        init_src();
 
        return 0;