[PATCH 5.5 179/399] iommu/amd: Only support x2APIC with IVHD type 11h/40h

Greg Kroah-Hartman
2020-02-21T07:51:18Z

From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>

[ Upstream commit 966b753cf3969553ca50bacd2b8c4ddade5ecc9e ]

Current implementation for IOMMU x2APIC support makes use of
the MMIO access to MSI capability block registers, which requires
checking EFR[MsiCapMmioSup]. However, only IVHD type 11h/40h contain
the information, and not in the IVHD type 10h IOMMU feature reporting
field. Since the BIOS in newer systems, which supports x2APIC, would
normally contain IVHD type 11h/40h, remove the IOMMU_FEAT_XTSUP_SHIFT
check for IVHD type 10h, and only support x2APIC with IVHD type 11h/40h.

Fixes: 66929812955b ('iommu/amd: Add support for X2APIC IOMMU interrupts')
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/amd_iommu_init.c | 2 --
drivers/iommu/amd_iommu_types.h | 1 -
2 files changed, 3 deletions(-)

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 61628c906ce11..d7cbca8bf2cd4 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1523,8 +1523,6 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h)
iommu->mmio_phys_end = MMIO_CNTR_CONF_OFFSET;
if (((h->efr_attr & (0x1 << IOMMU_FEAT_GASUP_SHIFT)) == 0))
amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY;
- if (((h->efr_attr & (0x1 << IOMMU_FEAT_XTSUP_SHIFT)) == 0))
- amd_iommu_xt_mode = IRQ_REMAP_XAPIC_MODE;
break;
case 0x11:
case 0x40:
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index f8a7945f3df90..798e1533a1471 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -377,7 +377,6 @@
#define IOMMU_CAP_EFR 27

/* IOMMU Feature Reporting Field (for IVHD type 10h */
-#define IOMMU_FEAT_XTSUP_SHIFT 0
#define IOMMU_FEAT_GASUP_SHIFT 6

/* IOMMU Extended Feature Register (EFR) */
--
2.20.1