feat(arm_fpga): determine GICR base by probing
When an Arm Ltd GIC (Arm GIC-[567]00) is instantiated with one or more
ITSes, the ITS MMIO frames appear between the distributor and
redistributor addresses. This makes the beginning of the redistributor
region dependent on the existence and number of ITSes.
To support various FPGA images, with and without ITSes, probe the
addresses in question, to learn whether they accommodate an ITS or a
redistributor. This can be safely done by looking at the PIDR[01]
registers, which contain an ID code for each region, documented in the
Arm GIC TRMs.
We try to find all ITSes instantiated, and skip either two or four 64K
frames, depending on GICv4.1 support. At some point we will find the
first redistributor; this address we then update in the DTB.
Change-Id: Iefb88c2afa989e044fe0b36b7020b56538c60b07
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/include/drivers/arm/gicv3.h b/include/drivers/arm/gicv3.h
index 973a58b..5efefb6 100644
--- a/include/drivers/arm/gicv3.h
+++ b/include/drivers/arm/gicv3.h
@@ -303,6 +303,8 @@
#define GITS_CTLR_ENABLED_BIT BIT_32(0)
#define GITS_CTLR_QUIESCENT_BIT BIT_32(1)
+#define GITS_TYPER_VSGI BIT_64(39)
+
#ifndef __ASSEMBLER__
#include <stdbool.h>
diff --git a/plat/arm/board/arm_fpga/fpga_bl31_setup.c b/plat/arm/board/arm_fpga/fpga_bl31_setup.c
index 1ad6488..abe68ad 100644
--- a/plat/arm/board/arm_fpga/fpga_bl31_setup.c
+++ b/plat/arm/board/arm_fpga/fpga_bl31_setup.c
@@ -224,7 +224,7 @@
INFO("Adjusting GICR DT region to cover %u cores\n",
nr_cores);
err = fdt_adjust_gic_redist(fdt, nr_cores,
- INVALID_BASE_ADDR,
+ fpga_get_redist_base(),
fpga_get_redist_size());
if (err < 0) {
ERROR("Error %d fixing up GIC DT node\n", err);
diff --git a/plat/arm/board/arm_fpga/fpga_gicv3.c b/plat/arm/board/arm_fpga/fpga_gicv3.c
index 4a97beb..c379e7d 100644
--- a/plat/arm/board/arm_fpga/fpga_gicv3.c
+++ b/plat/arm/board/arm_fpga/fpga_gicv3.c
@@ -1,13 +1,14 @@
/*
- * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020-2021, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <common/debug.h>
#include <common/fdt_wrappers.h>
-#include <drivers/arm/gicv3.h>
+#include <drivers/arm/arm_gicv3_common.h>
#include <drivers/arm/gic_common.h>
+#include <drivers/arm/gicv3.h>
#include <lib/mmio.h>
#include <libfdt.h>
@@ -21,6 +22,7 @@
};
static uintptr_t fpga_rdistif_base_addrs[PLATFORM_CORE_COUNT];
+static int nr_itses;
static unsigned int fpga_mpidr_to_core_pos(unsigned long mpidr)
{
@@ -38,6 +40,8 @@
void plat_fpga_gic_init(void)
{
const void *fdt = (void *)(uintptr_t)FPGA_PRELOADED_DTB_BASE;
+ uintptr_t gicr_base = 0U;
+ uint32_t iidr;
int node, ret;
node = fdt_node_offset_by_compatible(fdt, 0, "arm,gic-v3");
@@ -54,11 +58,66 @@
return;
}
- ret = fdt_get_reg_props_by_index(fdt, node, 1,
- &fpga_gicv3_driver_data.gicr_base, NULL);
- if (ret < 0) {
- WARN("Could not read GIC redistributor address from DT.\n");
- return;
+ iidr = mmio_read_32(fpga_gicv3_driver_data.gicd_base + GICD_IIDR);
+ if (((iidr & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_600) ||
+ ((iidr & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_700)) {
+ unsigned int frame_id;
+
+ /*
+ * According to the GIC TRMs, if there are any ITSes, they
+ * start four 64K pages after the distributor. After all
+ * the ITSes then follow the redistributors.
+ */
+ gicr_base = fpga_gicv3_driver_data.gicd_base + (4U << 16);
+
+ do {
+ uint64_t its_typer;
+
+ /* Each GIC component can be identified by its ID. */
+ frame_id = gicv3_get_component_partnum(gicr_base);
+
+ if (frame_id == PIDR_COMPONENT_ARM_REDIST) {
+ INFO("Found %d ITSes, redistributors start at 0x%llx\n",
+ nr_itses, (unsigned long long)gicr_base);
+ break;
+ }
+
+ if (frame_id != PIDR_COMPONENT_ARM_ITS) {
+ WARN("GICv3: found unexpected frame 0x%x\n",
+ frame_id);
+ gicr_base = 0U;
+ break;
+ }
+
+ /*
+ * Found an ITS, now work out if it supports virtual
+ * SGIs (for direct guest injection). If yes, each
+ * ITS occupies four 64K pages, otherwise just two.
+ */
+ its_typer = mmio_read_64(gicr_base + GITS_TYPER);
+ if ((its_typer & GITS_TYPER_VSGI) != 0U) {
+ gicr_base += 4U << 16;
+ } else {
+ gicr_base += 2U << 16;
+ }
+ nr_itses++;
+ } while (true);
+ }
+
+ /*
+ * If this is not a GIC-600 or -700, or the autodetection above failed,
+ * use the base address from the device tree.
+ */
+ if (gicr_base == 0U) {
+ ret = fdt_get_reg_props_by_index(fdt, node, 1,
+ &fpga_gicv3_driver_data.gicr_base,
+ NULL);
+ if (ret < 0) {
+ WARN("Could not read GIC redistributor address from DT.\n");
+ return;
+ }
+ } else {
+ fpga_gicv3_driver_data.gicr_base = gicr_base;
}
gicv3_driver_init(&fpga_gicv3_driver_data);
@@ -91,3 +150,8 @@
return gicv3_redist_size(typer_val);
}
+
+uintptr_t fpga_get_redist_base(void)
+{
+ return fpga_gicv3_driver_data.gicr_base;
+}
diff --git a/plat/arm/board/arm_fpga/fpga_private.h b/plat/arm/board/arm_fpga/fpga_private.h
index cc809c4..61c8992 100644
--- a/plat/arm/board/arm_fpga/fpga_private.h
+++ b/plat/arm/board/arm_fpga/fpga_private.h
@@ -26,6 +26,7 @@
unsigned int plat_fpga_calc_core_pos(uint32_t mpid);
unsigned int fpga_get_nr_gic_cores(void);
uintptr_t fpga_get_redist_size(void);
+uintptr_t fpga_get_redist_base(void);
#endif /* __ASSEMBLER__ */
