soc/amd/common/fsp/pci: Add helper methods for PCI IRQ table
These are helper methods for interacting with the
AMD_FSP_PCIE_DEVFUNC_REMAP_HOB_GUID.
BUG=b:184766519, b:184766197
TEST=Build guybrush
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: Id03d0b74ca12e7bcee11f8d13b0e802861c13923
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52911
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/soc/amd/common/fsp/pci/pci_routing_info.c b/src/soc/amd/common/fsp/pci/pci_routing_info.c
new file mode 100644
index 0000000..21423da
--- /dev/null
+++ b/src/soc/amd/common/fsp/pci/pci_routing_info.c
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <amdblocks/amd_pci_util.h>
+#include <console/console.h>
+#include <device/pci_def.h>
+#include <fsp/util.h>
+#include <FspGuids.h>
+#include <types.h>
+
+const struct pci_routing_info *get_pci_routing_table(size_t *entries)
+{
+ static const struct pci_routing_info *routing_table;
+ static size_t routing_table_entries;
+
+ size_t hob_size = 0;
+
+ if (routing_table) {
+ *entries = routing_table_entries;
+ return routing_table;
+ }
+
+ routing_table = fsp_find_extension_hob_by_guid(AMD_FSP_PCIE_DEVFUNC_REMAP_HOB_GUID.b,
+ &hob_size);
+
+ if (routing_table == NULL || hob_size == 0) {
+ printk(BIOS_ERR, "Couldn't find PCIe routing HOB.\n");
+ return NULL;
+ }
+
+ routing_table_entries = hob_size / sizeof(struct pci_routing_info);
+
+ for (size_t i = 0; i < routing_table_entries; ++i) {
+ printk(BIOS_DEBUG, "%02x.%x: group: %u, swizzle: %u, irq: %u\n",
+ PCI_SLOT(routing_table[i].devfn), PCI_FUNC(routing_table[i].devfn),
+ routing_table[i].group, routing_table[i].swizzle, routing_table[i].irq);
+ }
+
+ *entries = routing_table_entries;
+
+ return routing_table;
+}