Add OPROM mapping support to coreboot

This allows to add a PCI ID mapping function for option roms so that the same
option rom can be used for a series of devices / PCI IDs. Intel and AMD often
use the same option rom for a number of PCI devices with differend IDs.

A function to implement such a mapping could look like this (or anything else
appropriate):

/* some vga option roms are used for several chipsets but they only have one
 * PCI ID in their header. If we encounter such an option rom, we need to do
 * the mapping ourselfes
 */

u32 map_oprom_vendev(u32 vendev)
{
    u32 new_vendev=vendev;

    switch(vendev) {
    case 0xa0118086:
        new_vendev=0xa0018086;
        break;
    }

    return new_vendev;
}

Change-Id: I1be7fe113b895075d43ea48fe706b039cef136d2
Reviewed-on: http://review.coreboot.org/573
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-by: Marc Jones <marcj303@gmail.com>

src/devices/pci_rom.c

@@ -37,6 +37,19 @@ struct rom_header *pci_rom_probe(struct device *dev)
 	/* If it's in FLASH, then don't check device for ROM. */
 	rom_header = cbfs_load_optionrom(dev->vendor, dev->device, NULL);
 
+	u32 vendev = dev->vendor | (dev->device << 16);
+	u32 mapped_vendev = vendev;
+
+	if (map_oprom_vendev)
+		mapped_vendev = map_oprom_vendev(vendev);
+
+	if (!rom_header) {
+		if (vendev != mapped_vendev) {
+			rom_header = cbfs_load_optionrom(mapped_vendev &
+					0xffff, mapped_vendev >> 16, NULL);
+		}
+	}
+
 	if (rom_header) {
 		printk(BIOS_DEBUG, "In CBFS, ROM address for %s = %p\n",
 		       dev_path(dev), rom_header);
@@ -78,8 +91,10 @@ struct rom_header *pci_rom_probe(struct device *dev)
 
 	printk(BIOS_SPEW, "PCI ROM image, vendor ID %04x, device ID %04x,\n",
 	       rom_data->vendor, rom_data->device);
-	if (dev->vendor != rom_data->vendor
+	/* If the device id is mapped, a mismatch is expected */
-	    || dev->device != rom_data->device) {
+	if ((dev->vendor != rom_data->vendor
+	    || dev->device != rom_data->device)
+	    && (vendev == mapped_vendev)) {
 		printk(BIOS_ERR, "ID mismatch: vendor ID %04x, "
 		       "device ID %04x\n", rom_data->vendor, rom_data->device);
 		return NULL;

src/include/device/pci_rom.h

@@ -35,5 +35,6 @@ struct  pci_data {
 
 struct rom_header *pci_rom_probe(struct device *dev);
 struct rom_header *pci_rom_load(struct device *dev, struct rom_header *rom_header);
+u32 __attribute__((weak)) map_oprom_vendev(u32 vendev);
 
 #endif