x86: Use PCI method for enabling AMD extended config space before MSR method

While both methods should work equivalently well for the native
case, the Xen Dom0 case can't reliably work with the MSR one,
since there's no guarantee that the virtual CPUs it has
available fully cover all necessary physical ones.

As per the suggestion of Robert Richter the patch only adds the
PCI method, but leaves the MSR one as a fallback to cover new
systems the PCI IDs of which may not have got added to the code
base yet.

The only change in v2 is the breaking out of the new CPI
initialization method into a separate function, as requested by
Ingo.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Robert Richter <robert.richter@amd.com>
Cc: Andreas Herrmann3 <Andreas.Herrmann3@amd.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
LKML-Reference: <4D2B3FD7020000780002B67D@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jan Beulich
2011-01-10 16:20:23 +00:00
committed by Ingo Molnar
parent 29fe359ca2
commit 24d9b70b8c
4 changed files with 63 additions and 28 deletions

View File

@@ -4,6 +4,7 @@
#include <linux/cpu.h>
#include <linux/range.h>
#include <asm/amd_nb.h>
#include <asm/pci_x86.h>
#include <asm/pci-direct.h>
@@ -378,6 +379,34 @@ static struct notifier_block __cpuinitdata amd_cpu_notifier = {
.notifier_call = amd_cpu_notify,
};
static void __init pci_enable_pci_io_ecs(void)
{
#ifdef CONFIG_AMD_NB
unsigned int i, n;
for (n = i = 0; !n && amd_nb_bus_dev_ranges[i].dev_limit; ++i) {
u8 bus = amd_nb_bus_dev_ranges[i].bus;
u8 slot = amd_nb_bus_dev_ranges[i].dev_base;
u8 limit = amd_nb_bus_dev_ranges[i].dev_limit;
for (; slot < limit; ++slot) {
u32 val = read_pci_config(bus, slot, 3, 0);
if (!early_is_amd_nb(val))
continue;
val = read_pci_config(bus, slot, 3, 0x8c);
if (!(val & (ENABLE_CF8_EXT_CFG >> 32))) {
val |= ENABLE_CF8_EXT_CFG >> 32;
write_pci_config(bus, slot, 3, 0x8c, val);
}
++n;
}
}
pr_info("Extended Config Space enabled on %u nodes\n", n);
#endif
}
static int __init pci_io_ecs_init(void)
{
int cpu;
@@ -386,6 +415,10 @@ static int __init pci_io_ecs_init(void)
if (boot_cpu_data.x86 < 0x10)
return 0;
/* Try the PCI method first. */
if (early_pci_allowed())
pci_enable_pci_io_ecs();
register_cpu_notifier(&amd_cpu_notifier);
for_each_online_cpu(cpu)
amd_cpu_notify(&amd_cpu_notifier, (unsigned long)CPU_ONLINE,