fix(gicv3): workaround for NVIDIA erratum T241-FABRIC-4

The purpose of this patch is to address the T241 erratum T241-FABRIC-4,
which causes unexpected behavior in the GIC when multiple transactions
are received simultaneously from different sources. This hardware issue
impacts NVIDIA server platforms that use more than two T241 chips
interconnected. Each chip has support for 320 {E}SPIs.

This issue occurs when multiple packets from different GICs are
incorrectly interleaved at the target chip. The erratum text below
specifies exactly what can cause multiple transfer packets susceptible
to interleaving and GIC state corruption. GIC state corruption can
lead to a range of problems, including kernel panics, and unexpected
behavior.

Erratum documentation:
https://developer.nvidia.com/docs/t241-fabric-4/nvidia-t241-fabric-4-errata.pdf

The workaround is to ensure that MMIO accesses target the GIC on the
socket that holds the data, for example SPI ranges owned by the socket’s
GIC. This ensures that the GIC will not utilize the inter-socket AXI
Stream interface for servicing these GIC MMIO accesses.

This patch updates the functions that use the GICD_In{E} registers to
ensure that the accesses are directed to the chip that owns the SPI,
instead of using the global alias.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I04e33ba64eb306bd5fdabb56e63cbe273d8cd632
diff --git a/drivers/arm/gic/v3/gicv3_main.c b/drivers/arm/gic/v3/gicv3_main.c
index f6c251d..168d0eb 100644
--- a/drivers/arm/gic/v3/gicv3_main.c
+++ b/drivers/arm/gic/v3/gicv3_main.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2015-2022, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2023, NVIDIA Corporation. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -10,6 +11,7 @@
 #include <arch_helpers.h>
 #include <common/debug.h>
 #include <common/interrupt_props.h>
+#include <drivers/arm/gic600_multichip.h>
 #include <drivers/arm/gicv3.h>
 #include <lib/spinlock.h>
 #include <plat/common/platform.h>
@@ -430,6 +432,7 @@
 {
 	unsigned int igroup, grpmodr;
 	uintptr_t gicr_base;
+	uintptr_t gicd_base;
 
 	assert(IS_IN_EL3());
 	assert(gicv3_driver_data != NULL);
@@ -453,8 +456,9 @@
 	} else {
 		/* SPIs: 32-1019, ESPIs: 4096-5119 */
 		assert(gicv3_driver_data->gicd_base != 0U);
-		igroup = gicd_get_igroupr(gicv3_driver_data->gicd_base, id);
-		grpmodr = gicd_get_igrpmodr(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		igroup = gicd_get_igroupr(gicd_base, id);
+		grpmodr = gicd_get_igrpmodr(gicd_base, id);
 	}
 
 	/*
@@ -930,6 +934,8 @@
  ******************************************************************************/
 unsigned int gicv3_get_interrupt_active(unsigned int id, unsigned int proc_num)
 {
+	uintptr_t gicd_base;
+
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
 	assert(proc_num < gicv3_driver_data->rdistif_num);
@@ -943,7 +949,8 @@
 	}
 
 	/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-	return gicd_get_isactiver(gicv3_driver_data->gicd_base, id);
+	gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+	return gicd_get_isactiver(gicd_base, id);
 }
 
 /*******************************************************************************
@@ -953,6 +960,8 @@
  ******************************************************************************/
 void gicv3_enable_interrupt(unsigned int id, unsigned int proc_num)
 {
+	uintptr_t gicd_base;
+
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
 	assert(proc_num < gicv3_driver_data->rdistif_num);
@@ -971,7 +980,8 @@
 			gicv3_driver_data->rdistif_base_addrs[proc_num], id);
 	} else {
 		/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-		gicd_set_isenabler(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		gicd_set_isenabler(gicd_base, id);
 	}
 }
 
@@ -982,6 +992,8 @@
  ******************************************************************************/
 void gicv3_disable_interrupt(unsigned int id, unsigned int proc_num)
 {
+	uintptr_t gicd_base;
+
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
 	assert(proc_num < gicv3_driver_data->rdistif_num);
@@ -1003,10 +1015,11 @@
 			gicv3_driver_data->rdistif_base_addrs[proc_num]);
 	} else {
 		/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-		gicd_set_icenabler(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		gicd_set_icenabler(gicd_base, id);
 
 		/* Write to clear enable requires waiting for pending writes */
-		gicd_wait_for_pending_write(gicv3_driver_data->gicd_base);
+		gicd_wait_for_pending_write(gicd_base);
 	}
 
 	dsbishst();
@@ -1020,6 +1033,7 @@
 		unsigned int priority)
 {
 	uintptr_t gicr_base;
+	uintptr_t gicd_base;
 
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
@@ -1033,7 +1047,8 @@
 		gicr_set_ipriorityr(gicr_base, id, priority);
 	} else {
 		/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-		gicd_set_ipriorityr(gicv3_driver_data->gicd_base, id, priority);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		gicd_set_ipriorityr(gicd_base, id, priority);
 	}
 }
 
@@ -1047,6 +1062,7 @@
 {
 	bool igroup = false, grpmod = false;
 	uintptr_t gicr_base;
+	uintptr_t gicd_base;
 
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
@@ -1086,10 +1102,12 @@
 		/* Serialize read-modify-write to Distributor registers */
 		spin_lock(&gic_lock);
 
-		igroup ? gicd_set_igroupr(gicv3_driver_data->gicd_base, id) :
-			 gicd_clr_igroupr(gicv3_driver_data->gicd_base, id);
-		grpmod ? gicd_set_igrpmodr(gicv3_driver_data->gicd_base, id) :
-			 gicd_clr_igrpmodr(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+
+		igroup ? gicd_set_igroupr(gicd_base, id) :
+			 gicd_clr_igroupr(gicd_base, id);
+		grpmod ? gicd_set_igrpmodr(gicd_base, id) :
+			 gicd_clr_igrpmodr(gicd_base, id);
 
 		spin_unlock(&gic_lock);
 	}
@@ -1165,6 +1183,7 @@
 {
 	unsigned long long aff;
 	uint64_t router;
+	uintptr_t gicd_base;
 
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
@@ -1174,14 +1193,15 @@
 	assert(IS_SPI(id));
 
 	aff = gicd_irouter_val_from_mpidr(mpidr, irm);
-	gicd_write_irouter(gicv3_driver_data->gicd_base, id, aff);
+	gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+	gicd_write_irouter(gicd_base, id, aff);
 
 	/*
 	 * In implementations that do not require 1 of N distribution of SPIs,
 	 * IRM might be RAZ/WI. Read back and verify IRM bit.
 	 */
 	if (irm == GICV3_IRM_ANY) {
-		router = gicd_read_irouter(gicv3_driver_data->gicd_base, id);
+		router = gicd_read_irouter(gicd_base, id);
 		if (((router >> IROUTER_IRM_SHIFT) & IROUTER_IRM_MASK) == 0U) {
 			ERROR("GICv3 implementation doesn't support routing ANY\n");
 			panic();
@@ -1196,6 +1216,8 @@
  ******************************************************************************/
 void gicv3_clear_interrupt_pending(unsigned int id, unsigned int proc_num)
 {
+	uintptr_t gicd_base;
+
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
 	assert(proc_num < gicv3_driver_data->rdistif_num);
@@ -1213,7 +1235,8 @@
 			gicv3_driver_data->rdistif_base_addrs[proc_num], id);
 	} else {
 		/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-		gicd_set_icpendr(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		gicd_set_icpendr(gicd_base, id);
 	}
 
 	dsbishst();
@@ -1226,6 +1249,8 @@
  ******************************************************************************/
 void gicv3_set_interrupt_pending(unsigned int id, unsigned int proc_num)
 {
+	uintptr_t gicd_base;
+
 	assert(gicv3_driver_data != NULL);
 	assert(gicv3_driver_data->gicd_base != 0U);
 	assert(proc_num < gicv3_driver_data->rdistif_num);
@@ -1244,7 +1269,8 @@
 			gicv3_driver_data->rdistif_base_addrs[proc_num], id);
 	} else {
 		/* For SPIs: 32-1019 and ESPIs: 4096-5119 */
-		gicd_set_ispendr(gicv3_driver_data->gicd_base, id);
+		gicd_base = gicv3_get_multichip_base(id, gicv3_driver_data->gicd_base);
+		gicd_set_ispendr(gicd_base, id);
 	}
 }