servo_micro: Fix DMA mappings

UART3 and 4 had DMA collisions. Remove DMA from UART4.

BRANCH=servo-9040
BUG=b:112701646,chromium:865478
TEST=reboot EC, no crashy

Change-Id: Ic44b363dafe938d6420b350eb1c5ab796da81f3c
Signed-off-by: Nick Sanders <nsanders@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1188514
Reviewed-by: Mary Ruthven <mruthven@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>

2 files changed, 35 insertions, 15 deletions

diff --git a/board/servo_micro/board.c b/board/servo_micro/board.c
index 355c091a77..a665b3dfe8 100644
--- a/board/servo_micro/board.c
+++ b/board/servo_micro/board.c
@@ -27,6 +27,31 @@
 
 #include "gpio_list.h"
 
+void board_config_pre_init(void)
+{
+	/* enable SYSCFG clock */
+	STM32_RCC_APB2ENR |= STM32_RCC_SYSCFGEN;
+
+	/*
+	 * the DMA mapping is :
+	 *  Chan 3 : USART3_RX
+	 *  Chan 5 : USART2_RX
+	 *  Chan 6 : USART4_RX (Disable)
+	 *  Chan 6 : SPI2_RX
+	 *  Chan 7 : SPI2_TX
+	 *
+	 *  i2c : no dma
+	 *  tim16/17: no dma
+	 */
+	STM32_SYSCFG_CFGR1 |= (1 << 26);  /* Remap USART3 RX/TX DMA */
+
+	/* Remap SPI2 to DMA channels 6 and 7 */
+	/* STM32F072 SPI2 defaults to using DMA channels 4 and 5 */
+	/* but cros_ec hardcodes a 6/7 assumption in registers.h */
+	STM32_SYSCFG_CFGR1 |= (1 << 24);
+
+}
+
 /******************************************************************************
  * Forward UARTs as a USB serial interface.
  */
@@ -35,13 +60,13 @@
 #define USB_STREAM_TX_SIZE	32
 
 /******************************************************************************
- * Forward USART2 as a simple USB serial interface.
+ * Forward USART2 (EC) as a simple USB serial interface.
  */
 
 static struct usart_config const usart2;
 struct usb_stream_config const usart2_usb;
 
-static struct queue const usart2_to_usb = QUEUE_DIRECT(256, uint8_t,
+static struct queue const usart2_to_usb = QUEUE_DIRECT(128, uint8_t,
 	usart2.producer, usart2_usb.consumer);
 static struct queue const usb_to_usart2 = QUEUE_DIRECT(64, uint8_t,
 	usart2_usb.producer, usart2.consumer);
@@ -70,13 +95,13 @@ USB_STREAM_CONFIG_USART_IFACE(usart2_usb,
 
 
 /******************************************************************************
- * Forward USART3 as a simple USB serial interface.
+ * Forward USART3 (CPU) as a simple USB serial interface.
  */
 
 static struct usart_config const usart3;
 struct usb_stream_config const usart3_usb;
 
-static struct queue const usart3_to_usb = QUEUE_DIRECT(256, uint8_t,
+static struct queue const usart3_to_usb = QUEUE_DIRECT(128, uint8_t,
 	usart3.producer, usart3_usb.consumer);
 static struct queue const usb_to_usart3 = QUEUE_DIRECT(64, uint8_t,
 	usart3_usb.producer, usart3.consumer);
@@ -105,23 +130,21 @@ USB_STREAM_CONFIG_USART_IFACE(usart3_usb,
 
 
 /******************************************************************************
- * Forward USART4 as a simple USB serial interface.
+ * Forward USART4 (cr50) as a simple USB serial interface.
+ *  We cannot enable DMA due to lack of DMA channels.
  */
 
 static struct usart_config const usart4;
 struct usb_stream_config const usart4_usb;
 
-static struct queue const usart4_to_usb = QUEUE_DIRECT(256, uint8_t,
+static struct queue const usart4_to_usb = QUEUE_DIRECT(64, uint8_t,
 	usart4.producer, usart4_usb.consumer);
 static struct queue const usb_to_usart4 = QUEUE_DIRECT(64, uint8_t,
 	usart4_usb.producer, usart4.consumer);
 
-static struct usart_rx_dma const usart4_rx_dma =
-	USART_RX_DMA(STM32_DMAC_CH6, 32);
-
 static struct usart_config const usart4 =
 	USART_CONFIG(usart4_hw,
-		usart4_rx_dma.usart_rx,
+		usart_rx_interrupt,
 		usart_tx_interrupt,
 		115200,
 		0,
@@ -504,11 +527,6 @@ const unsigned int spi_devices_used = ARRAY_SIZE(spi_devices);
 
 void usb_spi_board_enable(struct usb_spi_config const *config)
 {
-	/* Remap SPI2 to DMA channels 6 and 7 */
-	/* STM32F072 SPI2 defaults to using DMA channels 4 and 5 */
-	/* but cros_ec hardcodes a 6/7 assumption in registers.h */
-	STM32_SYSCFG_CFGR1 |= (1 << 24);
-
 	/* Configure SPI GPIOs */
 	gpio_config_module(MODULE_SPI_FLASH, 1);
 
diff --git a/board/servo_micro/board.h b/board/servo_micro/board.h
index 2a11e7707c..86aff61772 100644
--- a/board/servo_micro/board.h
+++ b/board/servo_micro/board.h
@@ -11,6 +11,8 @@
 /* 48 MHz SYSCLK clock frequency */
 #define CPU_CLOCK 48000000
 
+#define CONFIG_BOARD_PRE_INIT
+
 /* Enable USART1,3,4 and USB streams */
 #define CONFIG_STREAM_USART
 #define CONFIG_STREAM_USART2