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>

4 files changed, 47 insertions, 2 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();
 }
 
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index 8b6b1e05c306..3b25e49380c6 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -726,12 +726,22 @@ static inline void __init construct_default_ISA_mptable(int mpc_default_type)
 static struct intel_mp_floating *mpf_found;
 
 /*
+ * Machine specific quirk for finding the SMP config before other setup
+ * activities destroy the table:
+ */
+int (*mach_get_smp_config_quirk)(unsigned int early);
+
+/*
  * Scan the memory blocks for an SMP configuration block.
  */
-static void __init __get_smp_config(unsigned early)
+static void __init __get_smp_config(unsigned int early)
 {
         struct intel_mp_floating *mpf = mpf_found;
 
+        if (mach_get_smp_config_quirk) {
+                if (mach_get_smp_config_quirk(early))
+                        return;
+        }
         if (acpi_lapic && early)
                 return;
         /*
@@ -889,10 +899,16 @@ static int __init smp_scan_config(unsigned long base, unsigned long length,
         return 0;
 }
 
-static void __init __find_smp_config(unsigned reserve)
+int (*mach_find_smp_config_quirk)(unsigned int reserve);
+
+static void __init __find_smp_config(unsigned int reserve)
 {
         unsigned int address;
 
+        if (mach_find_smp_config_quirk) {
+                if (mach_find_smp_config_quirk(reserve))
+                        return;
+        }
         /*
          * FIXME: Linux assumes you have 640K of base ram..
          * this continues the error...
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index a7c3471ea17c..cb3db406247c 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -596,6 +596,7 @@ void __init setup_arch(char **cmdline_p)
 {
 #ifdef CONFIG_X86_32
         memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
+        visws_early_detect();
         pre_setup_arch_hook();
         early_cpu_init();
 #else
diff --git a/include/asm-x86/setup.h b/include/asm-x86/setup.h
index 1d121c632d9e..1ad7eae0d9be 100644
--- a/include/asm-x86/setup.h
+++ b/include/asm-x86/setup.h
@@ -8,6 +8,23 @@
 /* Interrupt control for vSMPowered x86_64 systems */
 void vsmp_init(void);
 
+#ifdef CONFIG_X86_VISWS
+extern void visws_early_detect(void);
+#else
+static inline void visws_early_detect(void) { }
+#endif
+
+/*
+ * Any setup quirks to be performed?
+ */
+extern int (*arch_time_init_quirk)(void);
+extern int (*arch_pre_intr_init_quirk)(void);
+extern int (*arch_intr_init_quirk)(void);
+extern int (*arch_trap_init_quirk)(void);
+extern char * (*arch_memory_setup_quirk)(void);
+extern int (*mach_get_smp_config_quirk)(unsigned int early);
+extern int (*mach_find_smp_config_quirk)(unsigned int reserve);
+
 #ifndef CONFIG_PARAVIRT
 #define paravirt_post_allocator_init()  do {} while (0)
 #endif