From 72c61f10053c20c4ae96823d8c934aed049a05ce Mon Sep 17 00:00:00 2001
From: Yonatan Schachter <yonatan.schachter@gmail.com>
Date: Mon, 7 Feb 2022 22:35:30 +0200
Subject: [PATCH] drivers: hwinfo: Added reset cause support for RPi Pico

Added support for hwinfo's reset cause functions, for the Raspberry Pi
Pico series.

Signed-off-by: Yonatan Schachter <yonatan.schachter@gmail.com>
---
 drivers/hwinfo/hwinfo_rpi_pico.c | 40 ++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/drivers/hwinfo/hwinfo_rpi_pico.c b/drivers/hwinfo/hwinfo_rpi_pico.c
index 2ca251389c0..2527adda992 100644
--- a/drivers/hwinfo/hwinfo_rpi_pico.c
+++ b/drivers/hwinfo/hwinfo_rpi_pico.c
@@ -7,9 +7,14 @@
 #include <string.h>
 #include <drivers/hwinfo.h>
 #include <hardware/flash.h>
+#include <hardware/structs/vreg_and_chip_reset.h>
 
 #define FLASH_RUID_DATA_BYTES 8
 
+#define HAD_RUN_BIT BIT(VREG_AND_CHIP_RESET_CHIP_RESET_HAD_RUN_LSB)
+#define HAD_PSM_RESTART_BIT BIT(VREG_AND_CHIP_RESET_CHIP_RESET_HAD_PSM_RESTART_LSB)
+#define HAD_POR_BIT BIT(VREG_AND_CHIP_RESET_CHIP_RESET_HAD_POR_LSB)
+
 ssize_t z_impl_hwinfo_get_device_id(uint8_t *buffer, size_t length)
 {
 	uint8_t id[FLASH_RUID_DATA_BYTES];
@@ -32,3 +37,38 @@ ssize_t z_impl_hwinfo_get_device_id(uint8_t *buffer, size_t length)
 
 	return length;
 }
+
+int z_impl_hwinfo_get_reset_cause(uint32_t *cause)
+{
+	uint32_t flags = 0;
+	uint32_t reset_register = vreg_and_chip_reset_hw->chip_reset;
+
+	if (reset_register & HAD_POR_BIT) {
+		flags |= RESET_POR;
+	}
+
+	if (reset_register & HAD_RUN_BIT) {
+		flags |= RESET_PIN;
+	}
+
+	if (reset_register & HAD_PSM_RESTART_BIT) {
+		flags |= RESET_DEBUG;
+	}
+
+	*cause = flags;
+	return 0;
+}
+
+int z_impl_hwinfo_clear_reset_cause(void)
+{
+	/* The reset register can't be modified, nothing to do. */
+
+	return -ENOSYS;
+}
+
+int z_impl_hwinfo_get_supported_reset_cause(uint32_t *supported)
+{
+	*supported = RESET_PIN | RESET_DEBUG | RESET_POR;
+
+	return 0;
+}