MA-12335 Canonical Boot Reason in Android Pie 9.0

Read boot reason from SRC(system reset controller) and report
it to kernel by "androidboot.bootreason=<>" kernel commandline.
This is enabled on imx6/7/7ulp/8m, imx8 will report default value
"androidboot.bootreason=reboot" since it can't get such info on
A core at u-boot stage.

Test: Boot reason report ok on imx6qp/imx7ulp/imx8qxp.

Change-Id: I03effaa03bc513bec6153e82c1a04e29c07e7db8
Signed-off-by: Ji Luo <ji.luo@nxp.com>

2 files changed, 32 insertions, 0 deletions

diff --git a/arch/arm/mach-imx/cpu.c b/arch/arm/mach-imx/cpu.c
index 3f19f7e4e5..67db961ea6 100644
--- a/arch/arm/mach-imx/cpu.c
+++ b/arch/arm/mach-imx/cpu.c
@@ -43,7 +43,12 @@ static char *get_reset_cause(void)
 	struct src *src_regs = (struct src *)SRC_BASE_ADDR;
 
 	cause = readl(&src_regs->srsr);
+#ifndef CONFIG_ANDROID_BOOT_IMAGE
+	/* We will read the ssrs states later for android so we don't
+	 * clear the states here.
+	 */
 	writel(cause, &src_regs->srsr);
+#endif
 	reset_cause = cause;
 
 	switch (cause) {
@@ -87,6 +92,17 @@ static char *get_reset_cause(void)
 	}
 }
 
+#ifdef CONFIG_ANDROID_BOOT_IMAGE
+void get_reboot_reason(char *ret)
+{
+	struct src *src_regs = (struct src *)SRC_BASE_ADDR;
+
+	strcpy(ret, (char *)get_reset_cause());
+	/* clear the srsr here, its state has been recorded in reset_cause */
+	writel(reset_cause, &src_regs->srsr);
+}
+#endif
+
 u32 get_imx_reset_cause(void)
 {
 	return reset_cause;
diff --git a/arch/arm/mach-imx/mx7ulp/soc.c b/arch/arm/mach-imx/mx7ulp/soc.c
index 81ce576334..10b2e18978 100644
--- a/arch/arm/mach-imx/mx7ulp/soc.c
+++ b/arch/arm/mach-imx/mx7ulp/soc.c
@@ -252,7 +252,12 @@ static char *get_reset_cause(char *ret)
 
 	srs = readl(reg_srs);
 	cause1 = readl(reg_ssrs);
+#ifndef CONFIG_ANDROID_BOOT_IMAGE
+	/* We will read the ssrs states later for android so we don't
+	 * clear the states here.
+	 */
 	writel(cause1, reg_ssrs);
+#endif
 
 	reset_cause = cause1;
 
@@ -292,6 +297,17 @@ static char *get_reset_cause(char *ret)
 	return ret;
 }
 
+#ifdef CONFIG_ANDROID_BOOT_IMAGE
+void get_reboot_reason(char *ret)
+{
+	u32 *reg_ssrs = (u32 *)(SRC_BASE_ADDR + 0x28);
+
+	get_reset_cause(ret);
+	/* clear the ssrs here, its state has been recorded in reset_cause */
+	writel(reset_cause, reg_ssrs);
+}
+#endif
+
 void arch_preboot_os(void)
 {
 #if defined(CONFIG_VIDEO_MXS)