feat(plat/zynqmp): add SDEI support

Add basic SDEI support, implementing the software event 0 only for now.
This already allows hypervisors like Jailhouse to use SDEI for internal
signaling while passing the GICC through to the guest (see also IMX8).

With SDEI on, we overrun the SRAM and need to stay in DRAM. So keep SDEI
off by default.
Co-developed-by: Angelo Ruocco <angeloruocco90@gmail.com>
Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Change-Id: Ic0d71b4ef0978c0a34393f4e3530ed1e24a39ca2

plat/xilinx/zynqmp/include/platform_def.h

@@ -36,7 +36,7 @@
  * little space for growth.
  */
 #ifndef ZYNQMP_ATF_MEM_BASE
-#if !DEBUG && defined(SPD_none)
+#if !DEBUG && defined(SPD_none) && !SDEI_SUPPORT
 # define BL31_BASE			0xfffea000
 # define BL31_LIMIT			0xffffffff
 #else
@@ -91,6 +91,13 @@
 #define CACHE_WRITEBACK_SHIFT   6
 #define CACHE_WRITEBACK_GRANULE (1 << CACHE_WRITEBACK_SHIFT)
 
+#define ZYNQMP_SDEI_SGI_PRIVATE		U(8)
+
+/* Platform macros to support exception handling framework */
+#define PLAT_PRI_BITS			U(3)
+#define PLAT_SDEI_CRITICAL_PRI		0x10
+#define PLAT_SDEI_NORMAL_PRI		0x20
+
 #define PLAT_ARM_GICD_BASE	BASE_GICD_BASE
 #define PLAT_ARM_GICC_BASE	BASE_GICC_BASE
 /*
@@ -102,8 +109,6 @@
 #define PLAT_ARM_G1S_IRQ_PROPS(grp) \
 	INTR_PROP_DESC(ARM_IRQ_SEC_PHY_TIMER, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_LEVEL), \
-	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_0, GIC_HIGHEST_SEC_PRIORITY, grp, \
-			GIC_INTR_CFG_EDGE), \
 	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_1, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_EDGE), \
 	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_2, GIC_HIGHEST_SEC_PRIORITY, grp, \
@@ -124,8 +129,6 @@
 			GIC_INTR_CFG_LEVEL), \
 	INTR_PROP_DESC(IRQ_TTC3_1, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_EDGE), \
-	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_0, GIC_HIGHEST_SEC_PRIORITY, grp, \
-			GIC_INTR_CFG_EDGE), \
 	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_1, GIC_HIGHEST_SEC_PRIORITY, grp, \
 			GIC_INTR_CFG_EDGE), \
 	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_2, GIC_HIGHEST_SEC_PRIORITY, grp, \
@@ -142,6 +145,8 @@
 			GIC_INTR_CFG_EDGE)
 #endif
 
-#define PLAT_ARM_G0_IRQ_PROPS(grp)
+#define PLAT_ARM_G0_IRQ_PROPS(grp) \
+	INTR_PROP_DESC(ARM_IRQ_SEC_SGI_0, PLAT_SDEI_NORMAL_PRI,	grp, \
+			GIC_INTR_CFG_EDGE)
 
 #endif /* PLATFORM_DEF_H */

plat/xilinx/zynqmp/platform.mk

@@ -14,6 +14,8 @@ override RESET_TO_BL31 := 1
 override GICV2_G0_FOR_EL3 := 1
 override WARMBOOT_ENABLE_DCACHE_EARLY := 1
 
+EL3_EXCEPTION_HANDLING := $(SDEI_SUPPORT)
+
 # Do not enable SVE
 ENABLE_SVE_FOR_NS	:= 0
 
@@ -107,6 +109,11 @@ BL31_SOURCES		+=	drivers/arm/cci/cci.c				\
 				plat/xilinx/zynqmp/pm_service/pm_api_clock.c	\
 				plat/xilinx/zynqmp/pm_service/pm_client.c
 
+ifeq (${SDEI_SUPPORT},1)
+BL31_SOURCES		+=	plat/xilinx/zynqmp/zynqmp_ehf.c			\
+				plat/xilinx/zynqmp/zynqmp_sdei.c
+endif
+
 BL31_CPPFLAGS		+=	-fno-jump-tables
 
 ifneq (${RESET_TO_BL31},1)

plat/xilinx/zynqmp/zynqmp_ehf.c

+/*
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) Siemens AG, 2020-2021
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <platform_def.h>
+
+#include <bl31/ehf.h>
+
+/*
+ * Enumeration of priority levels on ARM platforms.
+ */
+ehf_pri_desc_t zynqmp_exceptions[] = {
+	/* Critical priority SDEI */
+	EHF_PRI_DESC(PLAT_PRI_BITS, PLAT_SDEI_CRITICAL_PRI),
+
+	/* Normal priority SDEI */
+	EHF_PRI_DESC(PLAT_PRI_BITS, PLAT_SDEI_NORMAL_PRI),
+};
+
+/* Plug in ARM exceptions to Exception Handling Framework. */
+EHF_REGISTER_PRIORITIES(zynqmp_exceptions, ARRAY_SIZE(zynqmp_exceptions), PLAT_PRI_BITS);

plat/xilinx/zynqmp/zynqmp_sdei.c

+/*
+ * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) Siemens AG, 2020-2021
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/* SDEI configuration for ARM platforms */
+
+#include <bl31/ehf.h>
+#include <common/debug.h>
+#include <services/sdei.h>
+
+#include <plat/common/platform.h>
+#include <platform_def.h>
+
+int arm_validate_ns_entrypoint(uintptr_t entrypoint)
+{
+	return (entrypoint < BL31_BASE || entrypoint > BL31_LIMIT) ? 0 : -1;
+}
+
+/* Private event mappings */
+static sdei_ev_map_t zynqmp_sdei_private[] = {
+	SDEI_DEFINE_EVENT_0(ZYNQMP_SDEI_SGI_PRIVATE),
+};
+
+/* Shared event mappings */
+static sdei_ev_map_t zynqmp_sdei_shared[] = {
+};
+
+void plat_sdei_setup(void)
+{
+	INFO("SDEI platform setup\n");
+}
+
+/* Export ARM SDEI events */
+REGISTER_SDEI_MAP(zynqmp_sdei_private, zynqmp_sdei_shared);