[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240916171805.324292-6-suravee.suthikulpanit@amd.com>
Date: Mon, 16 Sep 2024 17:18:04 +0000
From: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
To: <linux-kernel@...r.kernel.org>, <iommu@...ts.linux.dev>
CC: <joro@...tes.org>, <robin.murphy@....com>, <vasant.hegde@....com>,
<jgg@...dia.com>, <kevin.tian@...el.com>, <jon.grimm@....com>,
<santosh.shukla@....com>, <pandoh@...gle.com>, <kumaranand@...gle.com>,
Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Subject: [PATCH v4 5/6] iommu/amd: Modify clear_dte_entry() to avoid in-place update
Lock DTE and copy value to a temporary storage before update using
cmpxchg128.
Also, refactor the function to simplify logic for applying erratum 63.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
---
drivers/iommu/amd/amd_iommu_types.h | 2 ++
drivers/iommu/amd/iommu.c | 28 ++++++++++++++++++++--------
2 files changed, 22 insertions(+), 8 deletions(-)
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index fea7544f8c55..db3ee094a144 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -425,6 +425,8 @@
#define DTE_GPT_LEVEL_SHIFT 54
+#define DTE_SYSMGT_MASK GENMASK_ULL(41, 40)
+
#define GCR3_VALID 0x01ULL
#define DTE_INTR_MASK (~GENMASK_ULL(55, 52))
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 676742d6f19a..2df679eb61c9 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2086,19 +2086,31 @@ static void set_dte_entry(struct amd_iommu *iommu,
}
}
-static void clear_dte_entry(struct amd_iommu *iommu, u16 devid)
+static void clear_dte_entry(struct amd_iommu *iommu, struct iommu_dev_data *dev_data)
{
- struct dev_table_entry *dev_table = get_dev_table(iommu);
+ struct dev_table_entry new;
+ struct dev_table_entry *dte = &get_dev_table(iommu)[dev_data->devid];
+
+ /*
+ * Need to preserve DTE[96:106] because certain fields are
+ * programmed using value in IVRS table from early init phase.
+ */
+ new.data[0] = DTE_FLAG_V;
- /* remove entry from the device table seen by the hardware */
- dev_table[devid].data[0] = DTE_FLAG_V;
+ /* Apply erratum 63 */
+ if (FIELD_GET(DTE_SYSMGT_MASK, dte->data[1]) == 0x01)
+ new.data[0] |= BIT_ULL(DEV_ENTRY_IW);
if (!amd_iommu_snp_en)
- dev_table[devid].data[0] |= DTE_FLAG_TV;
+ new.data[0] |= DTE_FLAG_TV;
+
+ /* Need to preserve DTE[96:106] */
+ new.data[1] = dte->data[1] & DTE_FLAG_MASK;
- dev_table[devid].data[1] &= DTE_FLAG_MASK;
+ /* Need to preserve interrupt remapping information in DTE[128:255] */
+ new.data128[1] = dte->data128[1];
- amd_iommu_apply_erratum_63(iommu, devid);
+ update_dte256(iommu, dev_data, &new);
}
/* Update and flush DTE for the given device */
@@ -2109,7 +2121,7 @@ void amd_iommu_dev_update_dte(struct iommu_dev_data *dev_data, bool set)
if (set)
set_dte_entry(iommu, dev_data);
else
- clear_dte_entry(iommu, dev_data->devid);
+ clear_dte_entry(iommu, dev_data);
clone_aliases(iommu, dev_data->dev);
device_flush_dte(dev_data);
--
2.34.1
Powered by blists - more mailing lists