[PATCH 1/5] iommu/amd: restore GA log/tail pointer on host resume

Maxim Levitsky
2021-11-23T16:10:54Z

This will give IOMMU GA log a chance to work after resume
from s3/s4.

Fixes: 8bda0cfbdc1a6 ("iommu/amd: Detect and initialize guest vAPIC log")

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
drivers/iommu/amd/init.c | 31 +++++++++++++++----------------
1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 1eacd43cb4368..8dae85fcfc2eb 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -806,16 +806,27 @@ static int iommu_ga_log_enable(struct amd_iommu *iommu)
{
#ifdef CONFIG_IRQ_REMAP
u32 status, i;
+ u64 entry;

if (!iommu->ga_log)
return -EINVAL;

- status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
-
/* Check if already running */
- if (status & (MMIO_STATUS_GALOG_RUN_MASK))
+ status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+ if (WARN_ON(status & (MMIO_STATUS_GALOG_RUN_MASK)))
return 0;

+ entry = iommu_virt_to_phys(iommu->ga_log) | GA_LOG_SIZE_512;
+ memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_BASE_OFFSET,
+ &entry, sizeof(entry));
+ entry = (iommu_virt_to_phys(iommu->ga_log_tail) &
+ (BIT_ULL(52)-1)) & ~7ULL;
+ memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_TAIL_OFFSET,
+ &entry, sizeof(entry));
+ writel(0x00, iommu->mmio_base + MMIO_GA_HEAD_OFFSET);
+ writel(0x00, iommu->mmio_base + MMIO_GA_TAIL_OFFSET);
+
+
iommu_feature_enable(iommu, CONTROL_GAINT_EN);
iommu_feature_enable(iommu, CONTROL_GALOG_EN);

@@ -825,7 +836,7 @@ static int iommu_ga_log_enable(struct amd_iommu *iommu)
break;
}

- if (i >= LOOP_TIMEOUT)
+ if (WARN_ON(i >= LOOP_TIMEOUT))
return -EINVAL;
#endif /* CONFIG_IRQ_REMAP */
return 0;
@@ -834,8 +845,6 @@ static int iommu_ga_log_enable(struct amd_iommu *iommu)
static int iommu_init_ga_log(struct amd_iommu *iommu)
{
#ifdef CONFIG_IRQ_REMAP
- u64 entry;
-
if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
return 0;

@@ -849,16 +858,6 @@ static int iommu_init_ga_log(struct amd_iommu *iommu)
if (!iommu->ga_log_tail)
goto err_out;

- entry = iommu_virt_to_phys(iommu->ga_log) | GA_LOG_SIZE_512;
- memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_BASE_OFFSET,
- &entry, sizeof(entry));
- entry = (iommu_virt_to_phys(iommu->ga_log_tail) &
- (BIT_ULL(52)-1)) & ~7ULL;
- memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_TAIL_OFFSET,
- &entry, sizeof(entry));
- writel(0x00, iommu->mmio_base + MMIO_GA_HEAD_OFFSET);
- writel(0x00, iommu->mmio_base + MMIO_GA_TAIL_OFFSET);
-
return 0;
err_out:
free_ga_log(iommu);
--
2.26.3