Commit e5699a82 authored by Ravikiran G Thirumalai's avatar Ravikiran G Thirumalai Committed by Ingo Molnar
Browse files

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: default avatarRavikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 43cdf5d6

arch/x86/kernel/vsmp_64.c

+19 −9
Original line number Diff line number Diff line
@@ -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;