[Intel-wired-lan,iwl-next,v3,10/12] iavf: Implement checking DD desc field

Commit Message

Mateusz Polchlopek April 3, 2024, 1:19 p.m. UTC

Rx timestamping introduced in PF driver caused the need of refactoring
the VF driver mechanism to check packet fields.

The function to check errors in descriptor has been removed and from
now only previously set struct fields are being checked. The field DD
(descriptor done) needs to be checked at the very beginning, before
extracting other fields.

Reviewed-by: Wojciech Drewek <[e-mail]>
Signed-off-by: Mateusz Polchlopek <[e-mail]>
---
 drivers/net/ethernet/intel/iavf/iavf_txrx.c | 28 ++++++++++++++++++++-
 drivers/net/ethernet/intel/iavf/iavf_txrx.h | 17 -------------
 drivers/net/ethernet/intel/iavf/iavf_type.h |  1 +
 3 files changed, 28 insertions(+), 18 deletions(-)

Patch

diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
index e2f46e29945f..b97da9c946ce 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
@@ -8,6 +8,28 @@ 
 #include "iavf_trace.h"
 #include "iavf_prototype.h"
 
+/**
+ * iavf_is_descriptor_done - tests DD bit in Rx descriptor
+ * @rx_ring: the ring parameter to distinguish descriptor type (flex/legacy)
+ * @rx_desc: pointer to receive descriptor
+ *
+ * This function tests the descriptor done bit in specified descriptor. Because
+ * there are two types of descriptors (legacy and flex) the parameter rx_ring
+ * is used to distinguish.
+ */
+static bool iavf_is_descriptor_done(struct iavf_ring *rx_ring,
+				    union iavf_rx_desc *rx_desc)
+{
+	u64 status_error_len = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+
+	if (rx_ring->rxdid == VIRTCHNL_RXDID_1_32B_BASE)
+		return !!(FIELD_GET(IAVF_RX_DESC_STATUS_DD_MASK,
+			  status_error_len));
+
+	return !!(FIELD_GET((IAVF_RX_FLEX_DESC_STATUS_ERR0_DD_BIT),
+		  le16_to_cpu(rx_desc->flex_wb.status_error0)));
+}
+
 static __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
 			 u32 td_tag)
 {
@@ -1718,7 +1740,11 @@  static int iavf_clean_rx_irq(struct iavf_ring *rx_ring, int budget)
 		 * verified the descriptor has been written back.
 		 */
 		dma_rmb();
-		if (!iavf_test_staterr(rx_desc, IAVF_RX_DESC_STATUS_DD_MASK))
+
+		/* If DD field (descriptor done) is unset then other fields are
+		 * not valid
+		 */
+		if (!iavf_is_descriptor_done(rx_ring, rx_desc))
 			break;
 
 		iavf_extract_rx_fields(rx_ring, rx_desc, &fields);
diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.h b/drivers/net/ethernet/intel/iavf/iavf_txrx.h
index 67e51b4883bc..54d858303839 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.h
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.h
@@ -153,23 +153,6 @@  static inline int iavf_skb_pad(void)
 #define IAVF_SKB_PAD (NET_SKB_PAD + NET_IP_ALIGN)
 #endif
 
-/**
- * iavf_test_staterr - tests bits in Rx descriptor status and error fields
- * @rx_desc: pointer to receive descriptor (in le64 format)
- * @stat_err_bits: value to mask
- *
- * This function does some fast chicanery in order to return the
- * value of the mask which is really only used for boolean tests.
- * The status_error_len doesn't need to be shifted because it begins
- * at offset zero.
- */
-static inline bool iavf_test_staterr(union iavf_rx_desc *rx_desc,
-				     const u64 stat_err_bits)
-{
-	return !!(rx_desc->wb.qword1.status_error_len &
-		  cpu_to_le64(stat_err_bits));
-}
-
 struct iavf_rx_extracted {
 	unsigned int size;
 	u16 vlan_tag;
diff --git a/drivers/net/ethernet/intel/iavf/iavf_type.h b/drivers/net/ethernet/intel/iavf/iavf_type.h
index e80d1f7b3052..5527e6479ebd 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_type.h
+++ b/drivers/net/ethernet/intel/iavf/iavf_type.h
@@ -318,6 +318,7 @@  union iavf_32byte_rx_desc {
  */
 #define IAVF_RX_DESC_STATUS_INT_UDP_0_MASK	BIT(18)
 
+#define IAVF_RX_FLEX_DESC_STATUS_ERR0_DD_BIT	BIT(0)
 #define IAVF_RX_FLEX_DESC_STATUS_ERR0_EOP_BIT	BIT(1)
 #define IAVF_RX_FLEX_DESC_STATUS_ERR0_RXE_BIT	BIT(10)