clk: imx5: retain early UART clocks during kernel init

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>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/clk/imx/clk-imx51-imx53.c

@@ -130,6 +130,20 @@ static const char *cpu_podf_sels[] = { "pll1_sw", "step_sel" };
 static struct clk *clk[IMX5_CLK_END];
 static struct clk_onecell_data clk_data;
 
+static struct clk ** const uart_clks[] __initconst = {
+	&clk[IMX5_CLK_UART1_IPG_GATE],
+	&clk[IMX5_CLK_UART1_PER_GATE],
+	&clk[IMX5_CLK_UART2_IPG_GATE],
+	&clk[IMX5_CLK_UART2_PER_GATE],
+	&clk[IMX5_CLK_UART3_IPG_GATE],
+	&clk[IMX5_CLK_UART3_PER_GATE],
+	&clk[IMX5_CLK_UART4_IPG_GATE],
+	&clk[IMX5_CLK_UART4_PER_GATE],
+	&clk[IMX5_CLK_UART5_IPG_GATE],
+	&clk[IMX5_CLK_UART5_PER_GATE],
+	NULL
+};
+
 static void __init mx5_clocks_common_init(void __iomem *ccm_base)
 {
 	clk[IMX5_CLK_DUMMY]		= imx_clk_fixed("dummy", 0);
@@ -310,6 +324,8 @@ static void __init mx5_clocks_common_init(void __iomem *ccm_base)
 	clk_prepare_enable(clk[IMX5_CLK_TMAX1]);
 	clk_prepare_enable(clk[IMX5_CLK_TMAX2]); /* esdhc2, fec */
 	clk_prepare_enable(clk[IMX5_CLK_TMAX3]); /* esdhc1, esdhc4 */
+
+	imx_register_uart_clocks(uart_clks);
 }
 
 static void __init mx50_clocks_init(struct device_node *np)