[PATCH v1 2/3] arm64: mach-k3: am625_init: Probe ESM nodes

[Julien Panis]

On AM62x devices, main ESM error event outputs can be routed to
MCU ESM as inputs. So, two ESM device nodes are expected in the
device tree : one for main ESM and another one for MCU ESM.
MCU ESM error output can trigger the reset logic to reset
the device when CTRLMMR_MCU_RST_CTRL:MCU_ESM_ERROR_RESET_EN_Z is
set to '0'.

Signed-off-by: Julien Panis <jpanis at baylibre.com>
---
 arch/arm/mach-k3/am625_init.c                 | 23 +++++++++++++++++++
 arch/arm/mach-k3/include/mach/am62_hardware.h |  3 +++
 2 files changed, 26 insertions(+)

diff --git a/arch/arm/mach-k3/am625_init.c b/arch/arm/mach-k3/am625_init.c
index 0d9525992bb0..dfd95b8053b5 100644
--- a/arch/arm/mach-k3/am625_init.c
+++ b/arch/arm/mach-k3/am625_init.c
@@ -64,6 +64,15 @@ static void ctrl_mmr_unlock(void)
 	mmr_unlock(PADCFG_MMR1_BASE, 1);
 }
 
+static __maybe_unused void enable_mcu_esm_reset(void)
+{
+	/* Set CTRLMMR_MCU_RST_CTRL:MCU_ESM_ERROR_RST_EN_Z  to '0' (low active) */
+	u32 stat = readl(CTRLMMR_MCU_RST_CTRL);
+
+	stat &= RST_CTRL_ESM_ERROR_RST_EN_Z_MASK;
+	writel(stat, CTRLMMR_MCU_RST_CTRL);
+}
+
 void board_init_f(ulong dummy)
 {
 	struct udevice *dev;
@@ -142,6 +151,20 @@ void board_init_f(ulong dummy)
 	/* Output System Firmware version info */
 	k3_sysfw_print_ver();
 
+	if (IS_ENABLED(CONFIG_ESM_K3)) {
+		/* Probe/configure ESM0 */
+		ret = uclass_get_device_by_name(UCLASS_MISC, "esm at 420000", &dev);
+		if (ret)
+			printf("esm main init failed: %d\n", ret);
+
+		/* Probe/configure MCUESM */
+		ret = uclass_get_device_by_name(UCLASS_MISC, "esm at 4100000", &dev);
+		if (ret)
+			printf("esm mcu init failed: %d\n", ret);
+
+		enable_mcu_esm_reset();
+	}
+
 #if defined(CONFIG_K3_AM64_DDRSS)
 	ret = uclass_get_device(UCLASS_RAM, 0, &dev);
 	if (ret)
diff --git a/arch/arm/mach-k3/include/mach/am62_hardware.h b/arch/arm/mach-k3/include/mach/am62_hardware.h
index cfabd20cbd79..9118d052042a 100644
--- a/arch/arm/mach-k3/include/mach/am62_hardware.h
+++ b/arch/arm/mach-k3/include/mach/am62_hardware.h
@@ -29,6 +29,7 @@
 #define MAIN_DEVSTAT_BACKUP_BOOTMODE_SHIFT	10
 #define MAIN_DEVSTAT_BACKUP_BOOTMODE_CFG_MASK	BIT(13)
 #define MAIN_DEVSTAT_BACKUP_BOOTMODE_CFG_SHIFT	13
+#define RST_CTRL_ESM_ERROR_RST_EN_Z_MASK	(~BIT(17))
 
 /* Primary Bootmode MMC Config macros */
 #define MAIN_DEVSTAT_PRIMARY_MMC_PORT_MASK	0x4
@@ -67,6 +68,8 @@
 #define MCU_CTRL_DEVICE_CLKOUT_32K_CTRL		(MCU_CTRL_MMR0_BASE + 0x8058)
 #define MCU_CTRL_DEVICE_CLKOUT_LFOSC_SELECT_VAL	(0x3)
 
+#define CTRLMMR_MCU_RST_CTRL			(MCU_CTRL_MMR0_BASE + 0x18170)
+
 #define ROM_ENTENDED_BOOT_DATA_INFO		0x43c3f1e0
 
 /* Use Last 2K as Scratch pad */
-- 
2.25.1