cleanup: move voltage rail detection to common

Single source the VDD rail sagging reset interrupt
Add VDD detection to C2D2 as well.

BRANCH=servo
BUG=none
TEST=builds

Change-Id: Iceac7d9fa7a9bde5a3c23c36e63b6d635d8812a3
Signed-off-by: Jett Rink <jettrink@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2064593
Reviewed-by: Diana Z <dzigterman@chromium.org>

4 files changed, 24 insertions, 21 deletions

diff --git a/board/c2d2/board.h b/board/c2d2/board.h
index 0eac431345..817bc68bc1 100644
--- a/board/c2d2/board.h
+++ b/board/c2d2/board.h
@@ -83,6 +83,13 @@
 
 /* Options features */
 #define CONFIG_ADC
+/*
+ * See 'Programmable voltage detector characteristics' in the STM32F072x8
+ * Datasheet. PVD Threshold 1 corresponds to a falling voltage threshold of
+ * min:2.09V, max:2.27V.
+ */
+#define CONFIG_PVD
+#define PVD_THRESHOLD 1
 
 /* This is not actually an EC so disable some features. */
 #undef CONFIG_WATCHDOG_HELP
diff --git a/board/servo_micro/board.c b/board/servo_micro/board.c
index f7a21a6d95..d778f021c2 100644
--- a/board/servo_micro/board.c
+++ b/board/servo_micro/board.c
@@ -386,15 +386,6 @@ const struct ite_dfu_config_t ite_dfu_config = {
 	.sda = GPIO_MASTER_I2C_SDA,
 };
 
-void pvd_interrupt(void) {
-	/* Clear Pending Register */
-	STM32_EXTI_PR = EXTI_PVD_EVENT;
-	/* Handle recovery by rebooting the system */
-	system_reset(0);
-}
-
-DECLARE_IRQ(STM32_IRQ_PVD, pvd_interrupt, HOOK_PRIO_FIRST);
-
 /******************************************************************************
  * Initialize board.
  */
diff --git a/board/servo_v4/board.c b/board/servo_v4/board.c
index 7661cee20c..bf1c51e267 100644
--- a/board/servo_v4/board.c
+++ b/board/servo_v4/board.c
@@ -410,15 +410,6 @@ int board_get_version(void)
 	return ver;
 }
 
-void pvd_interrupt(void) {
-	/* Clear Pending Register */
-	STM32_EXTI_PR = EXTI_PVD_EVENT;
-	/* Handle recovery by rebooting the system */
-	system_reset(0);
-}
-
-DECLARE_IRQ(STM32_IRQ_PVD, pvd_interrupt, HOOK_PRIO_FIRST);
-
 static void board_init(void)
 {
 	/* USB to serial queues */
diff --git a/chip/stm32/system.c b/chip/stm32/system.c
index 559de04197..5056b7e219 100644
--- a/chip/stm32/system.c
+++ b/chip/stm32/system.c
@@ -11,9 +11,10 @@
 #include "cpu.h"
 #include "flash.h"
 #include "gpio_chip.h"
+#include "hooks.h"
 #include "host_command.h"
-#include "registers.h"
 #include "panic.h"
+#include "registers.h"
 #include "system.h"
 #include "task.h"
 #include "util.h"
@@ -179,7 +180,10 @@ void chip_pre_init(void)
 }
 
 #ifdef CONFIG_PVD
-/* Configures the programmable voltage detector to monitor for brown out conditions. */
+/******************************************************************************
+ * Detects sagging Vdd voltage and resets the system via the programmable
+ * voltage detector interrupt.
+ */
 static void configure_pvd(void)
 {
 	/* Clear Interrupt Enable Mask Register. */
@@ -208,7 +212,17 @@ static void configure_pvd(void)
 	/* Enable the PVD Output. */
 	STM32_PWR_CR |= STM32_PWR_PVDE;
 }
-#endif
+
+void pvd_interrupt(void)
+{
+	/* Clear Pending Register */
+	STM32_EXTI_PR = EXTI_PVD_EVENT;
+	/* Handle recovery by rebooting the system */
+	system_reset(0);
+}
+DECLARE_IRQ(STM32_IRQ_PVD, pvd_interrupt, HOOK_PRIO_FIRST);
+
+#endif /* CONFIG_PVD */
 
 void system_pre_init(void)
 {