imx: imx_clock: uart: Add UART clock API

This patch adds an API to configure up the base UART clocks, taking a
bit-mask of silicon specific bits as an input from a higher layer in order
to direct the necessary clock source.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

plat/imx/common/imx_clock.c

@@ -50,3 +50,35 @@ void imx_clock_gate_enable(unsigned int id, bool enable)
 
 	mmio_write_32(addr, CCM_CCGR_SETTING0_DOM_CLK_ALWAYS);
 }
+
+void imx_clock_enable_uart(unsigned int uart_id, uint32_t uart_clk_en_bits)
+{
+	unsigned int ccm_trgt_id = CCM_TRT_ID_UART1_CLK_ROOT + uart_id;
+	unsigned int ccm_ccgr_id = CCM_CCGR_ID_UART1 + uart_id;
+
+	/* Check for error */
+	if (uart_id > MXC_MAX_UART_NUM)
+		return;
+
+	/* Set target register values */
+	imx_clock_target_set(ccm_trgt_id, uart_clk_en_bits);
+
+	/* Enable the clock gate */
+	imx_clock_gate_enable(ccm_ccgr_id, true);
+}
+
+void imx_clock_disable_uart(unsigned int uart_id)
+{
+	unsigned int ccm_trgt_id = CCM_TRT_ID_UART1_CLK_ROOT + uart_id;
+	unsigned int ccm_ccgr_id = CCM_CCGR_ID_UART1 + uart_id;
+
+	/* Check for error */
+	if (uart_id > MXC_MAX_UART_NUM)
+		return;
+
+	/* Disable the clock gate */
+	imx_clock_gate_enable(ccm_ccgr_id, false);
+
+	/* Clear the target */
+	imx_clock_target_clr(ccm_trgt_id, 0xFFFFFFFF);
+}

plat/imx/common/include/imx_clock.h

@@ -989,4 +989,7 @@ void imx_clock_gate_enable(unsigned int id, bool enable);
 
 void imx_clock_init(void);
 
+void imx_clock_enable_uart(unsigned int uart_id, uint32_t uart_clk_en_bits);
+void imx_clock_disable_uart(unsigned int uart_id);
+
 #endif /* __IMX_CLOCK_H__ */