diff mbox series

[net,2/9] net: hns3: add sync command to sync io-pgtable

Message ID 20241011094521.3008298-3-shaojijie@huawei.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series There are some bugfix for the HNS3 ethernet driver | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5 this patch: 5
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 46 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 5 this patch: 5
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-10-12--12-00 (tests: 777)

Commit Message

Jijie Shao Oct. 11, 2024, 9:45 a.m. UTC 
From: Jian Shen <shenjian15@huawei.com>

To avoid errors in pgtable prefectch, add a sync command to sync
io-pagtable.

Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Peiyang Wang <wangpeiyang1@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
---
 .../net/ethernet/hisilicon/hns3/hns3_enet.c   | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

Comments

Jakub Kicinski Oct. 16, 2024, 1:19 a.m. UTC | #1 
On Fri, 11 Oct 2024 17:45:14 +0800 Jijie Shao wrote:
> To avoid errors in pgtable prefectch, add a sync command to sync
> io-pagtable.

I've never seen net drivers call iommu_iotlb functions.
Could you provide more context on what this is doing and 
why such unusual handling is necessary?
Jijie Shao Oct. 16, 2024, 11:53 a.m. UTC | #2 
on 2024/10/16 9:19, Jakub Kicinski wrote:
> On Fri, 11 Oct 2024 17:45:14 +0800 Jijie Shao wrote:
>> To avoid errors in pgtable prefectch, add a sync command to sync
>> io-pagtable.
> I've never seen net drivers call iommu_iotlb functions.
> Could you provide more context on what this is doing and
> why such unusual handling is necessary?

Follow the reply of the previous patch.

In the case of large traffic, the TX bounce buffer may be used up.
At this point, we go to mapping/unmapping on TX path again.
So we added the sync command in driver to avoid hardware issue.

Thanks
Jijie Shao
diff mbox series

Patch

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index ac88e301f221..8760b4e9ade6 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -381,6 +381,24 @@  static const struct hns3_rx_ptype hns3_rx_ptype_tbl[] = {
 #define HNS3_INVALID_PTYPE \
 		ARRAY_SIZE(hns3_rx_ptype_tbl)
 
+static void hns3_dma_map_sync(struct device *dev, unsigned long iova)
+{
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+	struct iommu_iotlb_gather iotlb_gather;
+	size_t granule;
+
+	if (!domain || !iommu_is_dma_domain(domain))
+		return;
+
+	granule = 1 << __ffs(domain->pgsize_bitmap);
+	iova = ALIGN_DOWN(iova, granule);
+	iotlb_gather.start = iova;
+	iotlb_gather.end = iova + granule - 1;
+	iotlb_gather.pgsize = granule;
+
+	iommu_iotlb_sync(domain, &iotlb_gather);
+}
+
 static irqreturn_t hns3_irq_handle(int irq, void *vector)
 {
 	struct hns3_enet_tqp_vector *tqp_vector = vector;
@@ -1728,7 +1746,9 @@  static int hns3_map_and_fill_desc(struct hns3_enet_ring *ring, void *priv,
 				  unsigned int type)
 {
 	struct hns3_desc_cb *desc_cb = &ring->desc_cb[ring->next_to_use];
+	struct hnae3_handle *handle = ring->tqp->handle;
 	struct device *dev = ring_to_dev(ring);
+	struct hnae3_ae_dev *ae_dev;
 	unsigned int size;
 	dma_addr_t dma;
 
@@ -1760,6 +1780,13 @@  static int hns3_map_and_fill_desc(struct hns3_enet_ring *ring, void *priv,
 		return -ENOMEM;
 	}
 
+	/* Add a SYNC command to sync io-pgtale to avoid errors in pgtable
+	 * prefetch
+	 */
+	ae_dev = hns3_get_ae_dev(handle);
+	if (ae_dev->dev_version >= HNAE3_DEVICE_VERSION_V3)
+		hns3_dma_map_sync(dev, dma);
+
 	desc_cb->priv = priv;
 	desc_cb->length = size;
 	desc_cb->dma = dma;