common/sfc_efx/base: provide control to deliver RSS hash

When Rx queue is created, allow to specify if the driver would like
to get RSS hash value calculated by the hardware.

Use the flag to choose Rx prefix on Riverhead.

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>

drivers/common/sfc_efx/base/ef10_rx.c

@@ -926,6 +926,10 @@ ef10_rx_qcreate(
 			goto fail1;
 		}
 		erp->er_buf_size = type_data->ertd_default.ed_buf_size;
+		/*
+		 * Ignore EFX_RXQ_FLAG_RSS_HASH since if RSS hash is calculated
+		 * it is always delivered from HW in the pseudo-header.
+		 */
 		break;
 #if EFSYS_OPT_RX_PACKED_STREAM
 	case EFX_RXQ_TYPE_PACKED_STREAM:
@@ -955,14 +959,19 @@ ef10_rx_qcreate(
 			goto fail3;
 		}
 		erp->er_buf_size = type_data->ertd_packed_stream.eps_buf_size;
+		/* Packed stream pseudo header does not have RSS hash value */
+		if (flags & EFX_RXQ_FLAG_RSS_HASH) {
+			rc = ENOTSUP;
+			goto fail4;
+		}
 		break;
 #endif /* EFSYS_OPT_RX_PACKED_STREAM */
 #if EFSYS_OPT_RX_ES_SUPER_BUFFER
 	case EFX_RXQ_TYPE_ES_SUPER_BUFFER:
 		erpl = &ef10_essb_rx_prefix_layout;
 		if (type_data == NULL) {
 			rc = EINVAL;
-			goto fail4;
+			goto fail5;
 		}
 		params.es_bufs_per_desc =
 		    type_data->ertd_es_super_buffer.eessb_bufs_per_desc;
@@ -972,25 +981,29 @@ ef10_rx_qcreate(
 		    type_data->ertd_es_super_buffer.eessb_buf_stride;
 		params.hol_block_timeout =
 		    type_data->ertd_es_super_buffer.eessb_hol_block_timeout;
+		/*
+		 * Ignore EFX_RXQ_FLAG_RSS_HASH since if RSS hash is calculated
+		 * it is always delivered from HW in the pseudo-header.
+		 */
 		break;
 #endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
 	default:
 		rc = ENOTSUP;
-		goto fail5;
+		goto fail6;
 	}
 
 #if EFSYS_OPT_RX_PACKED_STREAM
 	if (params.ps_buf_size != 0) {
 		/* Check if datapath firmware supports packed stream mode */
 		if (encp->enc_rx_packed_stream_supported == B_FALSE) {
 			rc = ENOTSUP;
-			goto fail6;
+			goto fail7;
 		}
 		/* Check if packed stream allows configurable buffer sizes */
 		if ((params.ps_buf_size != MC_CMD_INIT_RXQ_EXT_IN_PS_BUFF_1M) &&
 		    (encp->enc_rx_var_packed_stream_supported == B_FALSE)) {
 			rc = ENOTSUP;
-			goto fail7;
+			goto fail8;
 		}
 	}
 #else /* EFSYS_OPT_RX_PACKED_STREAM */
@@ -1001,17 +1014,17 @@ ef10_rx_qcreate(
 	if (params.es_bufs_per_desc > 0) {
 		if (encp->enc_rx_es_super_buffer_supported == B_FALSE) {
 			rc = ENOTSUP;
-			goto fail8;
+			goto fail9;
 		}
 		if (!EFX_IS_P2ALIGNED(uint32_t, params.es_max_dma_len,
 			    EFX_RX_ES_SUPER_BUFFER_BUF_ALIGNMENT)) {
 			rc = EINVAL;
-			goto fail9;
+			goto fail10;
 		}
 		if (!EFX_IS_P2ALIGNED(uint32_t, params.es_buf_stride,
 			    EFX_RX_ES_SUPER_BUFFER_BUF_ALIGNMENT)) {
 			rc = EINVAL;
-			goto fail10;
+			goto fail11;
 		}
 	}
 #else /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
@@ -1031,7 +1044,7 @@ ef10_rx_qcreate(
 
 	if ((rc = efx_mcdi_init_rxq(enp, ndescs, eep, label, index,
 		    esmp, &params)) != 0)
-		goto fail11;
+		goto fail12;
 
 	erp->er_eep = eep;
 	erp->er_label = label;
@@ -1044,29 +1057,31 @@ ef10_rx_qcreate(
 
 	return (0);
 
+fail12:
+	EFSYS_PROBE(fail12);
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
 fail11:
 	EFSYS_PROBE(fail11);
-#if EFSYS_OPT_RX_ES_SUPER_BUFFER
 fail10:
 	EFSYS_PROBE(fail10);
 fail9:
 	EFSYS_PROBE(fail9);
-fail8:
-	EFSYS_PROBE(fail8);
 #endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
 #if EFSYS_OPT_RX_PACKED_STREAM
+fail8:
+	EFSYS_PROBE(fail8);
 fail7:
 	EFSYS_PROBE(fail7);
+#endif /* EFSYS_OPT_RX_PACKED_STREAM */
 fail6:
 	EFSYS_PROBE(fail6);
-#endif /* EFSYS_OPT_RX_PACKED_STREAM */
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
 fail5:
 	EFSYS_PROBE(fail5);
-#if EFSYS_OPT_RX_ES_SUPER_BUFFER
-fail4:
-	EFSYS_PROBE(fail4);
 #endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
 #if EFSYS_OPT_RX_PACKED_STREAM
+fail4:
+	EFSYS_PROBE(fail4);
 fail3:
 	EFSYS_PROBE(fail3);
 fail2:

drivers/common/sfc_efx/base/efx.h

@@ -2948,6 +2948,11 @@ typedef enum efx_rxq_type_e {
  * Rx checksum offload results.
  */
 #define	EFX_RXQ_FLAG_INNER_CLASSES	0x2
+/*
+ * Request delivery of the RSS hash calculated by HW to be used by
+ * the driver.
+ */
+#define	EFX_RXQ_FLAG_RSS_HASH		0x4
 
 LIBEFX_API
 extern	__checkReturn	efx_rc_t

drivers/common/sfc_efx/base/efx_rx.c

@@ -889,11 +889,26 @@ efx_rx_qcreate_internal(
 	    ndescs, id, flags, eep, erp)) != 0)
 		goto fail4;
 
+	/* Sanity check queue creation result */
+	if (flags & EFX_RXQ_FLAG_RSS_HASH) {
+		const efx_rx_prefix_layout_t *erplp = &erp->er_prefix_layout;
+		const efx_rx_prefix_field_info_t *rss_hash_field;
+
+		rss_hash_field =
+		    &erplp->erpl_fields[EFX_RX_PREFIX_FIELD_RSS_HASH];
+		if (rss_hash_field->erpfi_width_bits == 0)
+			goto fail5;
+	}
+
 	enp->en_rx_qcount++;
 	*erpp = erp;
 
 	return (0);
 
+fail5:
+	EFSYS_PROBE(fail5);
+
+	erxop->erxo_qdestroy(erp);
 fail4:
 	EFSYS_PROBE(fail4);
 
@@ -1717,6 +1732,10 @@ siena_rx_qcreate(
 	switch (type) {
 	case EFX_RXQ_TYPE_DEFAULT:
 		erp->er_buf_size = type_data->ertd_default.ed_buf_size;
+		/*
+		 * Ignore EFX_RXQ_FLAG_RSS_HASH since if RSS hash is calculated
+		 * it is always delivered from HW in the pseudo-header.
+		 */
 		break;
 
 	default:

drivers/common/sfc_efx/base/rhead_rx.c

@@ -624,13 +624,14 @@ rhead_rx_qcreate(
 	else
 		params.disable_scatter = encp->enc_rx_disable_scatter_supported;
 
+	if (flags & EFX_RXQ_FLAG_RSS_HASH) {
+		fields_mask |= 1U << EFX_RX_PREFIX_FIELD_RSS_HASH;
+		fields_mask |= 1U << EFX_RX_PREFIX_FIELD_RSS_HASH_VALID;
+	}
+
 	/*
 	 * LENGTH is required in EF100 host interface, as receive events
 	 * do not include the packet length.
-	 * NOTE: Required fields are hard-wired now. Future designs will
-	 * want to allow the client (driver) code to have control over
-	 * which fields are required or may be allow to request so-called
-	 * default Rx prefix (which ID is equal to 0).
 	 */
 	fields_mask |= 1U << EFX_RX_PREFIX_FIELD_LENGTH;
 	if ((rc = rhead_rx_choose_prefix_id(enp, fields_mask, &erpl)) != 0)