[blackmagic] [PATCH 2/3] stlink: add support for SRST handling

[Paul F. <fer...@gm...>]

This enables SRST signals in open drain mode for both stlinkv1 and
stlinkv2 hardware platforms.

Signed-off-by: Paul Fertser <fer...@gm...>
---
 src/platforms/stlink/platform.c |   15 +++++++++++++++
 src/platforms/stlink/platform.h |    8 ++++++++
 2 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/src/platforms/stlink/platform.c b/src/platforms/stlink/platform.c
index e8435b9..08fcd32 100644
--- a/src/platforms/stlink/platform.c
+++ b/src/platforms/stlink/platform.c
@@ -98,6 +98,11 @@ int platform_init(void)
 			GPIO_CNF_OUTPUT_PUSHPULL, TCK_PIN);
 	gpio_set_mode(TDI_PORT, GPIO_MODE_OUTPUT_50_MHZ, 
 			GPIO_CNF_OUTPUT_PUSHPULL, TDI_PIN);
+	uint16_t srst_pin = platform_hwversion() == 0 ?
+		SRST_PIN_V1 : SRST_PIN_V2;
+	gpio_set(SRST_PORT, srst_pin);
+	gpio_set_mode(SRST_PORT, GPIO_MODE_OUTPUT_50_MHZ, 
+			GPIO_CNF_OUTPUT_OPENDRAIN, srst_pin);
 	
 	gpio_set_mode(LED_PORT, GPIO_MODE_OUTPUT_2_MHZ, 
 			GPIO_CNF_OUTPUT_PUSHPULL, led_idle_run);
@@ -127,6 +132,16 @@ void platform_delay(uint32_t delay)
 	while(timeout_counter);
 }
 
+void platform_srst_set_val(bool assert)
+{
+	uint16_t pin;
+	pin = platform_hwversion() == 0 ? SRST_PIN_V1 : SRST_PIN_V2;
+	if (assert)
+		gpio_clear(SRST_PORT, pin);
+	else
+		gpio_set(SRST_PORT, pin);
+}
+
 void sys_tick_handler(void)
 {
 	if(running_status) 
diff --git a/src/platforms/stlink/platform.h b/src/platforms/stlink/platform.h
index cbfc0ba..1ee944c 100644
--- a/src/platforms/stlink/platform.h
+++ b/src/platforms/stlink/platform.h
@@ -79,6 +79,10 @@ extern usbd_device *usbdev;
 #define SWDIO_PIN	TMS_PIN
 #define SWCLK_PIN	TCK_PIN
 
+#define SRST_PORT	GPIOB
+#define SRST_PIN_V1	GPIO1
+#define SRST_PIN_V2	GPIO0
+
 #define LED_PORT	GPIOA
 /* Use PC14 for a "dummy" uart led. So we can observere at least with scope*/
 #define LED_PORT_UART	GPIOC
@@ -98,6 +102,9 @@ extern usbd_device *usbdev;
     gpio_set_mode(USBUSART_PORT, GPIO_MODE_OUTPUT_2_MHZ,                \
                   GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, USBUSART_TX_PIN);
 
+#define SRST_SET_VAL(x)				\
+    platform_srst_set_val(x)
+
 #define USB_DRIVER      stm32f103_usb_driver
 #define USB_IRQ         NVIC_USB_LP_CAN_RX0_IRQ
 #define USB_ISR          usb_lp_can_rx0_isr
@@ -152,6 +159,7 @@ int platform_init(void);
 void morse(const char *msg, char repeat);
 const char *platform_target_voltage(void);
 void platform_delay(uint32_t delay);
+void platform_srst_set_val(bool assert);
 
 /* <cdcacm.c> */
 void cdcacm_init(void);
-- 
1.7.3.4