feat(tc): allow secure watchdog timer to trigger periodically

This patch does the following:
  1. Configures SBSA secure watchdog timer as Group0 interrupt for
     TC platform while keeping it as Group1 secure interrupt for
     other CSS based SoCs.
  2. Programs the watchdog timer to trigger periodically
  3. Provides a Group0 interrupt handler for TC platform port to
     deactivate the EL3 interrupt due to expiry of secure watchdog
     timer and refresh it explicitly.

Change-Id: I3847d6eb7347c6ea0e527b97b096119ca1e6701b
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>

7 files changed, 64 insertions, 13 deletions

diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index ffbd4ca13..e8461f5a2 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -364,6 +364,7 @@ extern const unsigned int arm_pm_idle_states[];
 /* secure watchdog */
 void plat_arm_secure_wdt_start(void);
 void plat_arm_secure_wdt_stop(void);
+void plat_arm_secure_wdt_refresh(void);
 
 /* Get SOC-ID of ARM platform */
 uint32_t plat_arm_get_soc_id(void);
diff --git a/include/plat/arm/css/common/css_def.h b/include/plat/arm/css/common/css_def.h
index dde174c37..f87f857c5 100644
--- a/include/plat/arm/css/common/css_def.h
+++ b/include/plat/arm/css/common/css_def.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2023, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -52,18 +52,21 @@
  * terminology. On a GICv2 system or mode, the interrupts will be treated as
  * Group 0 interrupts.
  */
-#define CSS_G1S_IRQ_PROPS(grp) \
+#define CSS_G1S_INT_PROPS(grp) \
 	INTR_PROP_DESC(CSS_IRQ_MHU, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_LEVEL), \
 	INTR_PROP_DESC(CSS_IRQ_GPU_SMMU_0, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_LEVEL), \
 	INTR_PROP_DESC(CSS_IRQ_TZC, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_LEVEL), \
-	INTR_PROP_DESC(CSS_IRQ_TZ_WDOG, GIC_HIGHEST_SEC_PRIORITY, grp, \
-			GIC_INTR_CFG_LEVEL), \
 	INTR_PROP_DESC(CSS_IRQ_SEC_SYS_TIMER, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_LEVEL)
 
+#define CSS_G1S_IRQ_PROPS(grp) \
+	CSS_G1S_INT_PROPS(grp), \
+	INTR_PROP_DESC(CSS_IRQ_TZ_WDOG, GIC_HIGHEST_SEC_PRIORITY, grp, \
+			GIC_INTR_CFG_LEVEL)
+
 #if CSS_USE_SCMI_SDS_DRIVER
 /* Memory region for shared data storage */
 #define PLAT_ARM_SDS_MEM_BASE		ARM_SHARED_RAM_BASE
diff --git a/plat/arm/board/tc/include/platform_def.h b/plat/arm/board/tc/include/platform_def.h
index eea1be6ba..59fff6e2a 100644
--- a/plat/arm/board/tc/include/platform_def.h
+++ b/plat/arm/board/tc/include/platform_def.h
@@ -212,8 +212,11 @@
 #define PLAT_ARM_DRAM2_SIZE		ULL(0x180000000)
 #define PLAT_ARM_DRAM2_END		(PLAT_ARM_DRAM2_BASE + PLAT_ARM_DRAM2_SIZE - 1ULL)
 
-#define PLAT_ARM_G1S_IRQ_PROPS(grp)	CSS_G1S_IRQ_PROPS(grp)
-#define PLAT_ARM_G0_IRQ_PROPS(grp)	ARM_G0_IRQ_PROPS(grp)
+#define PLAT_ARM_G1S_IRQ_PROPS(grp)	CSS_G1S_INT_PROPS(grp)
+#define PLAT_ARM_G0_IRQ_PROPS(grp)	ARM_G0_IRQ_PROPS(grp),	\
+					INTR_PROP_DESC(SBSA_SECURE_WDOG_INTID,	\
+						GIC_HIGHEST_SEC_PRIORITY, grp, \
+						GIC_INTR_CFG_LEVEL)
 
 #define PLAT_ARM_SP_IMAGE_STACK_BASE	(PLAT_SP_IMAGE_NS_BUF_BASE +	\
 					 PLAT_SP_IMAGE_NS_BUF_SIZE)
@@ -229,9 +232,11 @@
 #define PLAT_ARM_MEM_PROT_ADDR		(V2M_FLASH0_BASE + \
 					 V2M_FLASH0_SIZE - V2M_FLASH_BLOCK_SIZE)
 
-/*Secure Watchdog Constants */
-#define SBSA_SECURE_WDOG_BASE		UL(0x2A480000)
+/* Secure Watchdog Constants */
+#define SBSA_SECURE_WDOG_CONTROL_BASE	UL(0x2A480000)
+#define SBSA_SECURE_WDOG_REFRESH_BASE	UL(0x2A490000)
 #define SBSA_SECURE_WDOG_TIMEOUT	UL(100)
+#define SBSA_SECURE_WDOG_INTID		86
 
 #define PLAT_ARM_SCMI_CHANNEL_COUNT	1
 
diff --git a/plat/arm/board/tc/platform.mk b/plat/arm/board/tc/platform.mk
index 63a923795..c75507a51 100644
--- a/plat/arm/board/tc/platform.mk
+++ b/plat/arm/board/tc/platform.mk
@@ -118,7 +118,8 @@ BL31_SOURCES		+=	${INTERCONNECT_SOURCES}	\
 				lib/fconf/fconf_dyn_cfg_getter.c	\
 				drivers/cfi/v2m/v2m_flash.c		\
 				lib/utils/mem_region.c			\
-				plat/arm/common/arm_nor_psci_mem_protect.c
+				plat/arm/common/arm_nor_psci_mem_protect.c	\
+				drivers/arm/sbsa/sbsa.c
 
 BL31_SOURCES		+=	${FDT_WRAPPERS_SOURCES}
 
diff --git a/plat/arm/board/tc/tc_bl31_setup.c b/plat/arm/board/tc/tc_bl31_setup.c
index 8ad1d3056..630324fb3 100644
--- a/plat/arm/board/tc/tc_bl31_setup.c
+++ b/plat/arm/board/tc/tc_bl31_setup.c
@@ -13,6 +13,7 @@
 #include <common/debug.h>
 #include <drivers/arm/css/css_mhu_doorbell.h>
 #include <drivers/arm/css/scmi.h>
+#include <drivers/arm/sbsa.h>
 #include <lib/fconf/fconf.h>
 #include <lib/fconf/fconf_dyn_cfg_getter.h>
 #include <plat/arm/common/plat_arm.h>
@@ -81,3 +82,37 @@ void __init bl31_plat_arch_setup(void)
 
 	fconf_populate("HW_CONFIG", hw_config_info->config_addr);
 }
+
+#if defined(SPD_spmd) && (SPMD_SPM_AT_SEL2 == 1)
+void tc_bl31_plat_runtime_setup(void)
+{
+	arm_bl31_plat_runtime_setup();
+
+	/* Start secure watchdog timer. */
+	plat_arm_secure_wdt_start();
+}
+
+void bl31_plat_runtime_setup(void)
+{
+	tc_bl31_plat_runtime_setup();
+}
+
+/*
+ * Platform handler for Group0 secure interrupt.
+ */
+int plat_spmd_handle_group0_interrupt(uint32_t intid)
+{
+	/* Trusted Watchdog timer is the only source of Group0 interrupt now. */
+	if (intid == SBSA_SECURE_WDOG_INTID) {
+		INFO("Watchdog restarted\n");
+		/* Refresh the timer. */
+		plat_arm_secure_wdt_refresh();
+
+		/* Deactivate the corresponding interrupt. */
+		plat_ic_end_of_interrupt(intid);
+		return 0;
+	}
+
+	return -1;
+}
+#endif /*defined(SPD_spmd) && (SPMD_SPM_AT_SEL2 == 1)*/
diff --git a/plat/arm/board/tc/tc_plat.c b/plat/arm/board/tc/tc_plat.c
index 228f2fab3..766bfb570 100644
--- a/plat/arm/board/tc/tc_plat.c
+++ b/plat/arm/board/tc/tc_plat.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020-2023, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020-2023, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -147,10 +147,15 @@ int plat_get_mbedtls_heap(void **heap_addr, size_t *heap_size)
 
 void plat_arm_secure_wdt_start(void)
 {
-	sbsa_wdog_start(SBSA_SECURE_WDOG_BASE, SBSA_SECURE_WDOG_TIMEOUT);
+	sbsa_wdog_start(SBSA_SECURE_WDOG_CONTROL_BASE, SBSA_SECURE_WDOG_TIMEOUT);
 }
 
 void plat_arm_secure_wdt_stop(void)
 {
-	sbsa_wdog_stop(SBSA_SECURE_WDOG_BASE);
+	sbsa_wdog_stop(SBSA_SECURE_WDOG_CONTROL_BASE);
+}
+
+void plat_arm_secure_wdt_refresh(void)
+{
+	sbsa_wdog_refresh(SBSA_SECURE_WDOG_REFRESH_BASE);
 }
diff --git a/plat/arm/common/arm_bl31_setup.c b/plat/arm/common/arm_bl31_setup.c
index 19efdd32e..8c62a9bb9 100644
--- a/plat/arm/common/arm_bl31_setup.c
+++ b/plat/arm/common/arm_bl31_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2022, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2023, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -43,6 +43,7 @@ CASSERT(BL31_BASE >= ARM_FW_CONFIG_LIMIT, assert_bl31_base_overflows);
 #pragma weak bl31_platform_setup
 #pragma weak bl31_plat_arch_setup
 #pragma weak bl31_plat_get_next_image_ep_info
+#pragma weak bl31_plat_runtime_setup
 
 #define MAP_BL31_TOTAL		MAP_REGION_FLAT(			\
 					BL31_START,			\