x86, efi: Fix PCI ROM handing in EFI boot stub, in 32-bit mode

The 'Attributes' argument to pci->Attributes() function is 64-bit. So
when invoking in 32-bit mode it takes two registers, not just one.

This fixes memory corruption when booting via the 32-bit EFI boot stub.

Signed-off-by: David Woodhouse <[email protected]>
Cc: <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>
Cc: Matt Fleming <[email protected]>

arch/x86/boot/compressed/eboot.c

@@ -295,10 +295,15 @@ static efi_status_t setup_efi_pci(struct boot_params *params)
 		if (!pci)
 			continue;
 
+#ifdef CONFIG_X86_64
 		status = efi_call_phys4(pci->attributes, pci,
 					EfiPciIoAttributeOperationGet, 0,
 					&attributes);
-
+#else
+		status = efi_call_phys5(pci->attributes, pci,
+					EfiPciIoAttributeOperationGet, 0, 0,
+					&attributes);
+#endif
 		if (status != EFI_SUCCESS)
 			continue;