[dpdk-dev] [PATCH 04/23] net/sfc/base: support equal stride super-buffer Rx mode

[Andrew Rybchenko]

Equal stride super-buffer Rx mode is supported by DPDK firmware
variant. One Rx descriptor provides many Rx buffers to firmware.
Rx buffers follow each other with specified stride.
Also it supports head of line blocking with timeout to address
drops when no Rx descriptors are available. So it gives extra time
to the driver to provide Rx descriptors before drop.

Signed-off-by: Andrew Rybchenko <arybchenko at solarflare.com>
---
 drivers/net/sfc/base/ef10_ev.c   | 30 +++++++++++----
 drivers/net/sfc/base/ef10_impl.h | 10 +++++
 drivers/net/sfc/base/ef10_rx.c   | 80 ++++++++++++++++++++++++++++++++++++----
 drivers/net/sfc/base/efx.h       | 34 ++++++++++++++++-
 drivers/net/sfc/base/efx_check.h |  7 ++++
 drivers/net/sfc/base/efx_impl.h  | 12 +++++-
 drivers/net/sfc/base/efx_rx.c    | 52 ++++++++++++++++++++++++++
 drivers/net/sfc/efsys.h          |  2 +
 8 files changed, 210 insertions(+), 17 deletions(-)

diff --git a/drivers/net/sfc/base/ef10_ev.c b/drivers/net/sfc/base/ef10_ev.c
index 6e00099..7f89a7b 100644
--- a/drivers/net/sfc/base/ef10_ev.c
+++ b/drivers/net/sfc/base/ef10_ev.c
@@ -749,7 +749,7 @@ ef10_ev_qstats_update(
 }
 #endif /* EFSYS_OPT_QSTATS */
 
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 
 static	__checkReturn	boolean_t
 ef10_ev_rx_packed_stream(
@@ -788,7 +788,18 @@ ef10_ev_rx_packed_stream(
 
 	if (new_buffer) {
 		flags |= EFX_PKT_PACKED_STREAM_NEW_BUFFER;
+#if EFSYS_OPT_RX_PACKED_STREAM
+		/*
+		 * If both packed stream and equal stride super-buffer
+		 * modes are compiled in, in theory credits should be
+		 * be maintained for packed stream only, but right now
+		 * these modes are not distinguished in the event queue
+		 * Rx queue state and it is OK to increment the counter
+		 * regardless (it might be event cheaper than branching
+		 * since neighbour structure member are updated as well).
+		 */
 		eersp->eers_rx_packed_stream_credits++;
+#endif
 		eersp->eers_rx_read_ptr++;
 	}
 	current_id = eersp->eers_rx_read_ptr & eersp->eers_rx_mask;
@@ -830,7 +841,7 @@ ef10_ev_rx_packed_stream(
 	return (should_abort);
 }
 
-#endif /* EFSYS_OPT_RX_PACKED_STREAM */
+#endif /* EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER */
 
 static	__checkReturn	boolean_t
 ef10_ev_rx(
@@ -864,7 +875,7 @@ ef10_ev_rx(
 	label = EFX_QWORD_FIELD(*eqp, ESF_DZ_RX_QLABEL);
 	eersp = &eep->ee_rxq_state[label];
 
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	/*
 	 * Packed stream events are very different,
 	 * so handle them separately
@@ -1364,8 +1375,9 @@ ef10_ev_rxlabel_init(
 	__in		efx_rxq_type_t type)
 {
 	efx_evq_rxq_state_t *eersp;
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	boolean_t packed_stream = (type == EFX_RXQ_TYPE_PACKED_STREAM);
+	boolean_t es_super_buffer = (type == EFX_RXQ_TYPE_ES_SUPER_BUFFER);
 #endif
 
 	_NOTE(ARGUNUSED(type))
@@ -1387,9 +1399,11 @@ ef10_ev_rxlabel_init(
 	eersp->eers_rx_read_ptr = 0;
 #endif
 	eersp->eers_rx_mask = erp->er_mask;
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	eersp->eers_rx_stream_npackets = 0;
-	eersp->eers_rx_packed_stream = packed_stream;
+	eersp->eers_rx_packed_stream = packed_stream || es_super_buffer;
+#endif
+#if EFSYS_OPT_RX_PACKED_STREAM
 	if (packed_stream) {
 		eersp->eers_rx_packed_stream_credits = (eep->ee_mask + 1) /
 		    EFX_DIV_ROUND_UP(EFX_RX_PACKED_STREAM_MEM_PER_CREDIT,
@@ -1423,9 +1437,11 @@ ef10_ev_rxlabel_fini(
 
 	eersp->eers_rx_read_ptr = 0;
 	eersp->eers_rx_mask = 0;
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	eersp->eers_rx_stream_npackets = 0;
 	eersp->eers_rx_packed_stream = B_FALSE;
+#endif
+#if EFSYS_OPT_RX_PACKED_STREAM
 	eersp->eers_rx_packed_stream_credits = 0;
 #endif
 }
diff --git a/drivers/net/sfc/base/ef10_impl.h b/drivers/net/sfc/base/ef10_impl.h
index 36229a7..4751faf 100644
--- a/drivers/net/sfc/base/ef10_impl.h
+++ b/drivers/net/sfc/base/ef10_impl.h
@@ -1216,6 +1216,16 @@ efx_mcdi_set_nic_global(
 
 #endif /* EFSYS_OPT_RX_PACKED_STREAM */
 
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+
+/*
+ * Maximum DMA length and buffer stride alignment.
+ * (see SF-119419-TC, 3.2)
+ */
+#define	EFX_RX_ES_SUPER_BUFFER_BUF_ALIGNMENT	64
+
+#endif
+
 #ifdef	__cplusplus
 }
 #endif
diff --git a/drivers/net/sfc/base/ef10_rx.c b/drivers/net/sfc/base/ef10_rx.c
index 32cca57..a2591cc 100644
--- a/drivers/net/sfc/base/ef10_rx.c
+++ b/drivers/net/sfc/base/ef10_rx.c
@@ -21,12 +21,16 @@ efx_mcdi_init_rxq(
 	__in		efsys_mem_t *esmp,
 	__in		boolean_t disable_scatter,
 	__in		boolean_t want_inner_classes,
-	__in		uint32_t ps_bufsize)
+	__in		uint32_t ps_bufsize,
+	__in		uint32_t es_bufs_per_desc,
+	__in		uint32_t es_max_dma_len,
+	__in		uint32_t es_buf_stride,
+	__in		uint32_t hol_block_timeout)
 {
 	efx_nic_cfg_t *encp = &(enp->en_nic_cfg);
 	efx_mcdi_req_t req;
-	uint8_t payload[MAX(MC_CMD_INIT_RXQ_EXT_IN_LEN,
-			    MC_CMD_INIT_RXQ_EXT_OUT_LEN)];
+	uint8_t payload[MAX(MC_CMD_INIT_RXQ_V3_IN_LEN,
+			    MC_CMD_INIT_RXQ_V3_OUT_LEN)];
 	int npages = EFX_RXQ_NBUFS(ndescs);
 	int i;
 	efx_qword_t *dma_addr;
@@ -44,6 +48,8 @@ efx_mcdi_init_rxq(
 
 	if (ps_bufsize > 0)
 		dma_mode = MC_CMD_INIT_RXQ_EXT_IN_PACKED_STREAM;
+	else if (es_bufs_per_desc > 0)
+		dma_mode = MC_CMD_INIT_RXQ_V3_IN_EQUAL_STRIDE_SUPER_BUFFER;
 	else
 		dma_mode = MC_CMD_INIT_RXQ_EXT_IN_SINGLE_PACKET;
 
@@ -70,9 +76,9 @@ efx_mcdi_init_rxq(
 	(void) memset(payload, 0, sizeof (payload));
 	req.emr_cmd = MC_CMD_INIT_RXQ;
 	req.emr_in_buf = payload;
-	req.emr_in_length = MC_CMD_INIT_RXQ_EXT_IN_LEN;
+	req.emr_in_length = MC_CMD_INIT_RXQ_V3_IN_LEN;
 	req.emr_out_buf = payload;
-	req.emr_out_length = MC_CMD_INIT_RXQ_EXT_OUT_LEN;
+	req.emr_out_length = MC_CMD_INIT_RXQ_V3_OUT_LEN;
 
 	MCDI_IN_SET_DWORD(req, INIT_RXQ_EXT_IN_SIZE, ndescs);
 	MCDI_IN_SET_DWORD(req, INIT_RXQ_EXT_IN_TARGET_EVQ, target_evq);
@@ -92,6 +98,19 @@ efx_mcdi_init_rxq(
 	MCDI_IN_SET_DWORD(req, INIT_RXQ_EXT_IN_OWNER_ID, 0);
 	MCDI_IN_SET_DWORD(req, INIT_RXQ_EXT_IN_PORT_ID, EVB_PORT_ID_ASSIGNED);
 
+	if (es_bufs_per_desc > 0) {
+		MCDI_IN_SET_DWORD(req,
+		    INIT_RXQ_V3_IN_ES_PACKET_BUFFERS_PER_BUCKET,
+		    es_bufs_per_desc);
+		MCDI_IN_SET_DWORD(req,
+		    INIT_RXQ_V3_IN_ES_MAX_DMA_LEN, es_max_dma_len);
+		MCDI_IN_SET_DWORD(req,
+		    INIT_RXQ_V3_IN_ES_PACKET_STRIDE, es_buf_stride);
+		MCDI_IN_SET_DWORD(req,
+		    INIT_RXQ_V3_IN_ES_HEAD_OF_LINE_BLOCK_TIMEOUT,
+		    hol_block_timeout);
+	}
+
 	dma_addr = MCDI_IN2(req, efx_qword_t, INIT_RXQ_IN_DMA_ADDR);
 	addr = EFSYS_MEM_ADDR(esmp);
 
@@ -1006,6 +1025,10 @@ ef10_rx_qcreate(
 	boolean_t disable_scatter;
 	boolean_t want_inner_classes;
 	unsigned int ps_buf_size;
+	uint32_t es_bufs_per_desc = 0;
+	uint32_t es_max_dma_len = 0;
+	uint32_t es_buf_stride = 0;
+	uint32_t hol_block_timeout = 0;
 
 	_NOTE(ARGUNUSED(id, erp, type_data))
 
@@ -1054,6 +1077,19 @@ ef10_rx_qcreate(
 		}
 		break;
 #endif /* EFSYS_OPT_RX_PACKED_STREAM */
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+	case EFX_RXQ_TYPE_ES_SUPER_BUFFER:
+		ps_buf_size = 0;
+		es_bufs_per_desc =
+		    type_data->ertd_es_super_buffer.eessb_bufs_per_desc;
+		es_max_dma_len =
+		    type_data->ertd_es_super_buffer.eessb_max_dma_len;
+		es_buf_stride =
+		    type_data->ertd_es_super_buffer.eessb_buf_stride;
+		hol_block_timeout =
+		    type_data->ertd_es_super_buffer.eessb_hol_block_timeout;
+		break;
+#endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
 	default:
 		rc = ENOTSUP;
 		goto fail4;
@@ -1077,6 +1113,27 @@ ef10_rx_qcreate(
 	EFSYS_ASSERT(ps_buf_size == 0);
 #endif /* EFSYS_OPT_RX_PACKED_STREAM */
 
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+	if (es_bufs_per_desc > 0) {
+		if (encp->enc_rx_es_super_buffer_supported == B_FALSE) {
+			rc = ENOTSUP;
+			goto fail7;
+		}
+		if (!IS_P2ALIGNED(es_max_dma_len,
+			    EFX_RX_ES_SUPER_BUFFER_BUF_ALIGNMENT)) {
+			rc = EINVAL;
+			goto fail8;
+		}
+		if (!IS_P2ALIGNED(es_buf_stride,
+			    EFX_RX_ES_SUPER_BUFFER_BUF_ALIGNMENT)) {
+			rc = EINVAL;
+			goto fail9;
+		}
+	}
+#else /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
+	EFSYS_ASSERT(es_bufs_per_desc == 0);
+#endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
+
 	/* Scatter can only be disabled if the firmware supports doing so */
 	if (flags & EFX_RXQ_FLAG_SCATTER)
 		disable_scatter = B_FALSE;
@@ -1090,8 +1147,9 @@ ef10_rx_qcreate(
 
 	if ((rc = efx_mcdi_init_rxq(enp, ndescs, eep->ee_index, label, index,
 		    esmp, disable_scatter, want_inner_classes,
-		    ps_buf_size)) != 0)
-		goto fail7;
+		    ps_buf_size, es_bufs_per_desc, es_max_dma_len,
+		    es_buf_stride, hol_block_timeout)) != 0)
+		goto fail10;
 
 	erp->er_eep = eep;
 	erp->er_label = label;
@@ -1102,8 +1160,16 @@ ef10_rx_qcreate(
 
 	return (0);
 
+fail10:
+	EFSYS_PROBE(fail10);
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+fail9:
+	EFSYS_PROBE(fail9);
+fail8:
+	EFSYS_PROBE(fail8);
 fail7:
 	EFSYS_PROBE(fail7);
+#endif /* EFSYS_OPT_RX_ES_SUPER_BUFFER */
 #if EFSYS_OPT_RX_PACKED_STREAM
 fail6:
 	EFSYS_PROBE(fail6);
diff --git a/drivers/net/sfc/base/efx.h b/drivers/net/sfc/base/efx.h
index dea8d60..b334cc5 100644
--- a/drivers/net/sfc/base/efx.h
+++ b/drivers/net/sfc/base/efx.h
@@ -1864,7 +1864,7 @@ typedef	__checkReturn	boolean_t
 	__in		uint32_t size,
 	__in		uint16_t flags);
 
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 
 /*
  * Packed stream mode is documented in SF-112241-TC.
@@ -1874,6 +1874,13 @@ typedef	__checkReturn	boolean_t
  * packets are put there in a continuous stream.
  * The main advantage of such an approach is that RX queue refilling
  * happens much less frequently.
+ *
+ * Equal stride packed stream mode is documented in SF-119419-TC.
+ * The general idea is to utilize advantages of the packed stream,
+ * but avoid indirection in packets representation.
+ * The main advantage of such an approach is that RX queue refilling
+ * happens much less frequently and packets buffers are independent
+ * from upper layers point of view.
  */
 
 typedef	__checkReturn	boolean_t
@@ -1974,7 +1981,7 @@ typedef __checkReturn	boolean_t
 typedef struct efx_ev_callbacks_s {
 	efx_initialized_ev_t		eec_initialized;
 	efx_rx_ev_t			eec_rx;
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	efx_rx_ps_ev_t			eec_rx_ps;
 #endif
 	efx_tx_ev_t			eec_tx;
@@ -2281,6 +2288,7 @@ efx_pseudo_hdr_pkt_length_get(
 typedef enum efx_rxq_type_e {
 	EFX_RXQ_TYPE_DEFAULT,
 	EFX_RXQ_TYPE_PACKED_STREAM,
+	EFX_RXQ_TYPE_ES_SUPER_BUFFER,
 	EFX_RXQ_NTYPES
 } efx_rxq_type_t;
 
@@ -2334,6 +2342,28 @@ efx_rx_qcreate_packed_stream(
 
 #endif
 
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+
+/* Maximum head-of-line block timeout in nanoseconds */
+#define	EFX_RXQ_ES_SUPER_BUFFER_HOL_BLOCK_MAX	(400U * 1000 * 1000)
+
+extern	__checkReturn	efx_rc_t
+efx_rx_qcreate_es_super_buffer(
+	__in		efx_nic_t *enp,
+	__in		unsigned int index,
+	__in		unsigned int label,
+	__in		uint32_t n_bufs_per_desc,
+	__in		uint32_t max_dma_len,
+	__in		uint32_t buf_stride,
+	__in		uint32_t hol_block_timeout,
+	__in		efsys_mem_t *esmp,
+	__in		size_t ndescs,
+	__in		unsigned int flags,
+	__in		efx_evq_t *eep,
+	__deref_out	efx_rxq_t **erpp);
+
+#endif
+
 typedef struct efx_buffer_s {
 	efsys_dma_addr_t	eb_addr;
 	size_t			eb_size;
diff --git a/drivers/net/sfc/base/efx_check.h b/drivers/net/sfc/base/efx_check.h
index 52b0c79..ef5eadc 100644
--- a/drivers/net/sfc/base/efx_check.h
+++ b/drivers/net/sfc/base/efx_check.h
@@ -343,6 +343,13 @@
 # endif
 #endif
 
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+/* Support equal stride super-buffer mode */
+# if !(EFSYS_OPT_MEDFORD2)
+#  error "ES_SUPER_BUFFER requires MEDFORD2"
+# endif
+#endif
+
 /* Support hardware assistance for tunnels */
 #if EFSYS_OPT_TUNNEL
 # if !(EFSYS_OPT_MEDFORD || EFSYS_OPT_MEDFORD2)
diff --git a/drivers/net/sfc/base/efx_impl.h b/drivers/net/sfc/base/efx_impl.h
index f130713..548834f 100644
--- a/drivers/net/sfc/base/efx_impl.h
+++ b/drivers/net/sfc/base/efx_impl.h
@@ -137,6 +137,14 @@ typedef union efx_rxq_type_data_u {
 		uint32_t	eps_buf_size;
 	} ertd_packed_stream;
 #endif
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+	struct {
+		uint32_t	eessb_bufs_per_desc;
+		uint32_t	eessb_max_dma_len;
+		uint32_t	eessb_buf_stride;
+		uint32_t	eessb_hol_block_timeout;
+	} ertd_es_super_buffer;
+#endif
 } efx_rxq_type_data_t;
 
 typedef struct efx_rx_ops_s {
@@ -735,9 +743,11 @@ typedef	boolean_t (*efx_ev_handler_t)(efx_evq_t *, efx_qword_t *,
 typedef struct efx_evq_rxq_state_s {
 	unsigned int			eers_rx_read_ptr;
 	unsigned int			eers_rx_mask;
-#if EFSYS_OPT_RX_PACKED_STREAM
+#if EFSYS_OPT_RX_PACKED_STREAM || EFSYS_OPT_RX_ES_SUPER_BUFFER
 	unsigned int			eers_rx_stream_npackets;
 	boolean_t			eers_rx_packed_stream;
+#endif
+#if EFSYS_OPT_RX_PACKED_STREAM
 	unsigned int			eers_rx_packed_stream_credits;
 #endif
 } efx_evq_rxq_state_t;
diff --git a/drivers/net/sfc/base/efx_rx.c b/drivers/net/sfc/base/efx_rx.c
index 5f49b3a..1068a5c 100644
--- a/drivers/net/sfc/base/efx_rx.c
+++ b/drivers/net/sfc/base/efx_rx.c
@@ -836,6 +836,58 @@ efx_rx_qcreate_packed_stream(
 
 #endif
 
+#if EFSYS_OPT_RX_ES_SUPER_BUFFER
+
+	__checkReturn	efx_rc_t
+efx_rx_qcreate_es_super_buffer(
+	__in		efx_nic_t *enp,
+	__in		unsigned int index,
+	__in		unsigned int label,
+	__in		uint32_t n_bufs_per_desc,
+	__in		uint32_t max_dma_len,
+	__in		uint32_t buf_stride,
+	__in		uint32_t hol_block_timeout,
+	__in		efsys_mem_t *esmp,
+	__in		size_t ndescs,
+	__in		unsigned int flags,
+	__in		efx_evq_t *eep,
+	__deref_out	efx_rxq_t **erpp)
+{
+	efx_rc_t rc;
+	efx_rxq_type_data_t type_data;
+
+	if (hol_block_timeout > EFX_RXQ_ES_SUPER_BUFFER_HOL_BLOCK_MAX) {
+		rc = EINVAL;
+		goto fail1;
+	}
+
+	memset(&type_data, 0, sizeof(type_data));
+
+	type_data.ertd_es_super_buffer.eessb_bufs_per_desc = n_bufs_per_desc;
+	type_data.ertd_es_super_buffer.eessb_max_dma_len = max_dma_len;
+	type_data.ertd_es_super_buffer.eessb_buf_stride = buf_stride;
+	type_data.ertd_es_super_buffer.eessb_hol_block_timeout =
+	    hol_block_timeout;
+
+	rc = efx_rx_qcreate_internal(enp, index, label,
+	    EFX_RXQ_TYPE_ES_SUPER_BUFFER, &type_data, esmp, ndescs,
+	    0 /* id unused on EF10 */, flags, eep, erpp);
+	if (rc != 0)
+		goto fail2;
+
+	return (0);
+
+fail2:
+	EFSYS_PROBE(fail2);
+fail1:
+	EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+	return (rc);
+}
+
+#endif
+
+
 			void
 efx_rx_qdestroy(
 	__in		efx_rxq_t *erp)
diff --git a/drivers/net/sfc/efsys.h b/drivers/net/sfc/efsys.h
index 12f77dc..f71581c 100644
--- a/drivers/net/sfc/efsys.h
+++ b/drivers/net/sfc/efsys.h
@@ -198,6 +198,8 @@ prefetch_read_once(const volatile void *addr)
 
 #define EFSYS_OPT_RX_PACKED_STREAM 0
 
+#define EFSYS_OPT_RX_ES_SUPER_BUFFER 0
+
 #define EFSYS_OPT_TUNNEL 1
 
 #define EFSYS_OPT_FW_SUBVARIANT_AWARE 1
-- 
2.7.4