[PATCH v3 3/4] arch: arm: mach-k3: am642_init: Probe ESM nodes

[Hari Nagalla]

On AM64x devices, it is possible to route Main ESM0 error events to MCU
ESM. MCU ESM high error output can trigger the reset logic to reset the
device. So, for these devices we expect two ESM device nodes in the
device tree, one for Main ESM and the another MCU ESM in the device tree.
 When these ESM device nodes are properly configired it is possible to
route the Main RTI0 WWDT output to the MCU ESM high output through Main
ESM and trigger a device reset when
CTRLMMR_MCU_RST_CTRL:MCU_ESM_ERROR_RESET_EN_Z is set to '0'.

On K3 AM64x devices, the R5 SPL u-boot handles the ESM device node
configurations.

Signed-off-by: Hari Nagalla <hnagalla at ti.com>
---
 arch/arm/mach-k3/am642_init.c | 40 +++++++++++++++++++++++++++++++----
 1 file changed, 36 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-k3/am642_init.c b/arch/arm/mach-k3/am642_init.c
index 543dea02bc..3a75dcea35 100644
--- a/arch/arm/mach-k3/am642_init.c
+++ b/arch/arm/mach-k3/am642_init.c
@@ -24,12 +24,22 @@
 #include <dm/root.h>
 
 #if defined(CONFIG_SPL_BUILD)
+#define MCU_CTRL_MMR0_BASE			0x04500000
+#define CTRLMMR_MCU_RST_CTRL			0x04518170
 
 static void ctrl_mmr_unlock(void)
 {
 	/* Unlock all PADCFG_MMR1 module registers */
 	mmr_unlock(PADCFG_MMR1_BASE, 1);
 
+	/* Unlock all MCU_CTRL_MMR0 module registers */
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 0);
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 1);
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 2);
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 3);
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 4);
+	mmr_unlock(MCU_CTRL_MMR0_BASE, 6);
+
 	/* Unlock all CTRL_MMR0 module registers */
 	mmr_unlock(CTRL_MMR0_BASE, 0);
 	mmr_unlock(CTRL_MMR0_BASE, 1);
@@ -37,9 +47,6 @@ static void ctrl_mmr_unlock(void)
 	mmr_unlock(CTRL_MMR0_BASE, 3);
 	mmr_unlock(CTRL_MMR0_BASE, 5);
 	mmr_unlock(CTRL_MMR0_BASE, 6);
-
-	/* Unlock all MCU_PADCFG_MMR1 module registers */
-	mmr_unlock(MCU_PADCFG_MMR1_BASE, 1);
 }
 
 /*
@@ -142,9 +149,20 @@ int fdtdec_board_setup(const void *fdt_blob)
 }
 #endif
 
+#if defined(CONFIG_ESM_K3)
+static 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 &= 0xFFFDFFFF;
+	writel(stat, CTRLMMR_MCU_RST_CTRL);
+}
+#endif
+
 void board_init_f(ulong dummy)
 {
-#if defined(CONFIG_K3_LOAD_SYSFW) || defined(CONFIG_K3_AM64_DDRSS)
+#if defined(CONFIG_K3_LOAD_SYSFW) || defined(CONFIG_K3_AM64_DDRSS) || defined(CONFIG_ESM_K3)
 	struct udevice *dev;
 	int ret;
 #endif
@@ -194,6 +212,20 @@ void board_init_f(ulong dummy)
 	/* Output System Firmware version info */
 	k3_sysfw_print_ver();
 
+#if defined(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();
+#endif
+
 #if defined(CONFIG_K3_AM64_DDRSS)
 	ret = uclass_get_device(UCLASS_RAM, 0, &dev);
 	if (ret)
-- 
2.17.1