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authorRavikiran G Thirumalai <kiran@scalex86.org>2008-03-24 14:48:36 -0700
committerIngo Molnar <mingo@elte.hu>2008-04-17 17:41:29 +0200
commite5699a8231593d0e11e65ccf248549935304dab1 (patch)
tree2b02941763e26430574d2556d08a8a5b3f046e95 /arch/x86/kernel/vsmp_64.c
parent43cdf5d6e0a75c1069adc8d126b97b792ff53142 (diff)
downloadlinux-e5699a8231593d0e11e65ccf248549935304dab1.tar.gz
x86: clean up vSMP detection
vSMP detection: access pci config space early in boot to detect if the system is a vSMPowered box, and cache the result in a flag, so that is_vsmp_box() retrieves the value of the flag always. Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/vsmp_64.c')
-rw-r--r--arch/x86/kernel/vsmp_64.c28
1 files changed, 19 insertions, 9 deletions
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index 1e9a791dbe3..caf2a26f5cf 100644
--- a/arch/x86/kernel/vsmp_64.c
+++ b/arch/x86/kernel/vsmp_64.c
@@ -108,25 +108,34 @@ static void __init set_vsmp_pv_ops(void)
#endif
#ifdef CONFIG_PCI
-static int vsmp = -1;
+static int is_vsmp = -1;
-int is_vsmp_box(void)
+static void __init detect_vsmp_box(void)
{
- if (vsmp != -1)
- return vsmp;
+ is_vsmp = 0;
- vsmp = 0;
if (!early_pci_allowed())
- return vsmp;
+ return;
- /* Check if we are running on a ScaleMP vSMP box */
+ /* Check if we are running on a ScaleMP vSMPowered box */
if (read_pci_config(0, 0x1f, 0, PCI_VENDOR_ID) ==
(PCI_VENDOR_ID_SCALEMP | (PCI_DEVICE_ID_SCALEMP_VSMP_CTL << 16)))
- vsmp = 1;
+ is_vsmp = 1;
+}
- return vsmp;
+int is_vsmp_box(void)
+{
+ if (is_vsmp != -1)
+ return is_vsmp;
+ else {
+ WARN_ON_ONCE(1);
+ return 0;
+ }
}
#else
+static int __init detect_vsmp_box(void)
+{
+}
int is_vsmp_box(void)
{
return 0;
@@ -135,6 +144,7 @@ int is_vsmp_box(void)
void __init vsmp_init(void)
{
+ detect_vsmp_box();
if (!is_vsmp_box())
return;