x86/acpi: Add VFCT table

Add VFCT table to provide PCI Optiom Rom for
AMD graphic devices.
Useful for GNU Linux payloads and embedded dual GPU systems.

Tested on Lenovo T500 with AMD RV635 as secondary gpu.

Original Change-Id: I3b4a587c71e7165338cad3aca77ed5afa085a63c
Signed-off-by: Patrick Rudolph <siro@das-labor.org>

Change-Id: I4dc00005270240c048272b2e4f52ae46ba1c9422
Reviewed-on: https://review.coreboot.org/18192
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/src/device/pci_rom.c b/src/device/pci_rom.c
index 8366fea357..20621d36b2 100644
--- a/src/device/pci_rom.c
+++ b/src/device/pci_rom.c
@@ -169,3 +169,68 @@ struct rom_header *pci_rom_load(struct device *dev,
 	pci_ram_image_start += rom_size;
 	return (struct rom_header *) (pci_ram_image_start-rom_size);
 }
+
+/* ACPI */
+#if IS_ENABLED(CONFIG_HAVE_ACPI_TABLES)
+static unsigned long
+pci_rom_acpi_fill_vfct(struct device *device,
+					   struct acpi_vfct *vfct_struct,
+					   unsigned long current)
+{
+	struct acpi_vfct_image_hdr *header = &vfct_struct->image_hdr;
+	struct rom_header *rom;
+
+	vfct_struct->VBIOSImageOffset = (size_t)header - (size_t)vfct_struct;
+
+	rom = pci_rom_probe(device);
+	if (!rom) {
+		printk(BIOS_ERR, "pci_rom_acpi_fill_vfct failed\n");
+		return current;
+	}
+
+	header->DeviceID = device->device;
+	header->VendorID = device->vendor;
+	header->PCIBus = device->bus->secondary;
+	header->PCIFunction = PCI_FUNC(device->path.pci.devfn);
+	header->PCIDevice = PCI_SLOT(device->path.pci.devfn);
+	header->ImageLength = rom->size * 512;
+	memcpy((void *)&header->VbiosContent, rom, header->ImageLength);
+
+	current += header->ImageLength;
+	return current;
+}
+
+unsigned long
+pci_rom_write_acpi_tables(struct device *device,
+						  unsigned long current,
+						  struct acpi_rsdp *rsdp)
+{
+	struct acpi_vfct *vfct;
+	struct rom_header *rom;
+
+	/* Only handle VGA devices */
+	if ((device->class >> 8) != PCI_CLASS_DISPLAY_VGA)
+		return current;
+
+	/* Only handle enabled devices */
+	if (!device->enabled)
+		return current;
+
+	/* Probe for option rom */
+	rom = pci_rom_probe(device);
+	if (!rom)
+		return current;
+
+	/* AMD/ATI uses VFCT */
+	if (device->vendor == PCI_VENDOR_ID_ATI) {
+		current = ALIGN(current, 8);
+		printk(BIOS_DEBUG, "ACPI:   * VFCT at %lx\n", current);
+		vfct = (struct acpi_vfct *)current;
+		acpi_create_vfct(device, vfct, pci_rom_acpi_fill_vfct);
+		current += vfct->header.length;
+		acpi_add_table(rsdp, vfct);
+	}
+
+	return current;
+}
+#endif