[PATCH] Remove EFI memmap quirk for UV2+

Alex Thorlton
2015-12-11T20:59:51Z

Commit a5d90c923bcf ("x86/efi: Quirk out SGI UV") added a quirk to
efi_apply_memmap_quirks to force SGI UV systems to fall back to the old
EFI memmap mechanism. We have a BIOS fix for this issue on all systems
except for UV1. This commit fixes up the EFI quirk/MMR mapping code so
that we only apply the special case to UV1 hardware.

Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Len Brown <len.brown@intel.com>
Cc: linux-efi@vger.kernel.org

---
arch/x86/kernel/apic/x2apic_uv_x.c | 5 ++++-
arch/x86/platform/efi/quirks.c | 17 +++++++++++++----
2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 4a13946..96ba195 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -888,7 +888,10 @@ void __init uv_system_init(void)
return;
}
pr_info("UV: Found %s hub\n", hub);
- map_low_mmrs();
+
+ /* We now only need to map the MMRs on UV1 */
+ if (is_uv1_hub())
+ map_low_mmrs();

m_n_config.v = uv_read_local_mmr(UVH_RH_GAM_CONFIG_MMR );
m_val = m_n_config.s.m_skt;
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 1c7380d..2d66db8 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -8,6 +8,7 @@
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <linux/acpi.h>
+#include <linux/dmi.h>
#include <asm/efi.h>
#include <asm/uv/uv.h>

@@ -248,6 +249,16 @@ out:
return ret;
}

+static const struct dmi_system_id sgi_uv1_dmi[] = {
+ { NULL, "SGI UV1",
+ { DMI_MATCH(DMI_PRODUCT_NAME, "Stoutland Platform"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "1.0"),
+ DMI_MATCH(DMI_BIOS_VENDOR, "SGI.COM"),
+ }
+ },
+ { } /* NULL entry stops DMI scanning */
+};
+
void __init efi_apply_memmap_quirks(void)
{
/*
@@ -260,10 +271,8 @@ void __init efi_apply_memmap_quirks(void)
efi_unmap_memmap();
}

- /*
- * UV doesn't support the new EFI pagetable mapping yet.
- */
- if (is_uv_system())
+ /* UV2+ BIOS has a fix for this issue. UV1 still needs the quirk. */
+ if (dmi_check_system(sgi_uv1_dmi))
set_bit(EFI_OLD_MEMMAP, &efi.flags);
}

--
1.8.5.6