x86: add early quirk support

Add early quirks support.

In preparation of enabling the generic architecture to boot on a VISWS.

This will allow us to remove the VISWS subarch and all its complications.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 0 deletions

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 9836a079cfd9..269d367d2ace 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1297,6 +1297,11 @@ void __init e820_reserve_resources(void)
         }
 }
 
+/*
+ * Non-standard memory setup can be specified via this quirk:
+ */
+char * (*arch_memory_setup_quirk)(void);
+
 char *__init default_machine_specific_memory_setup(void)
 {
         char *who = "BIOS-e820";
@@ -1337,6 +1342,12 @@ char *__init default_machine_specific_memory_setup(void)
 
 char *__init __attribute__((weak)) machine_specific_memory_setup(void)
 {
+        if (arch_memory_setup_quirk) {
+                char *who = arch_memory_setup_quirk();
+
+                if (who)
+                        return who;
+        }
         return default_machine_specific_memory_setup();
 }