Specify the LM4 GPIOs to use for UART1

UART0 is the EC console, and it's consistent.
UART1 is the AP console that we export via servo. It was connected to a
different set of GPIOS on the BDS.

BUG=chrome-os-partner:18343
TEST=build link, bds
BRANCH=none

Change-Id: Ib4c10fd4d2b7a8ffb4e41e216528d4760ba50de3
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/48975
Reviewed-by: Randall Spangler <rspangler@chromium.org>

board/bds/board.h

@@ -35,6 +35,9 @@ enum adc_channel
 /* Number of I2C ports used */
 #define I2C_PORTS_USED 1
 
+/* GPIOs for second UART port */
+#define CONFIG_UART1_GPIOS_PB0_1
+
 /* GPIO signal list */
 enum gpio_signal {
 	GPIO_RECOVERYn = 0,       /* Recovery signal from DOWN button */

board/link/board.h

@@ -119,6 +119,9 @@ enum adc_channel
 /* USB charge port */
 #define USB_CHARGE_PORT_COUNT 2
 
+/* GPIOs for second UART port */
+#define CONFIG_UART1_GPIOS_PC4_5
+
 /* GPIO signal definitions. */
 enum gpio_signal {
 	/* Inputs with interrupt handlers are first for efficiency */

chip/lm4/uart.c

@@ -145,16 +145,17 @@ DECLARE_IRQ(LM4_IRQ_UART1, uart_1_interrupt, 2);
  */
 static void configure_gpio(void)
 {
-#ifdef BOARD_link
 	/* UART0 RX and TX are GPIO PA0:1 alternate function 1 */
 	gpio_set_alternate_function(LM4_GPIO_A, 0x03, 1);
+
+#if defined(CONFIG_UART1_GPIOS_PC4_5)
 	/* UART1 RX and TX are GPIO PC4:5 alternate function 2 */
 	gpio_set_alternate_function(LM4_GPIO_C, 0x30, 2);
-#else
-	/* UART0 RX and TX are GPIO PA0:1 alternate function 1 */
-	gpio_set_alternate_function(LM4_GPIO_A, 0x03, 1);
+#elif defined(CONFIG_UART1_GPIOS_PB0_1)
 	/* UART1 RX and TX are GPIO PB0:1 alternate function 1*/
 	gpio_set_alternate_function(LM4_GPIO_B, 0x03, 1);
+#else
+#error "Must put UART1 GPIOs somewhere"
 #endif
 }