[PATCH v1 6/9] baseband/acc101: support HARQ loopback

[Nicolas Chautru <nicolas.chautru@intel.com>]

Add function to do HARQ loopback on top of
default 5G UL processing.

Signed-off-by: Nicolas Chautru <nicolas.chautru@intel.com>
---
 doc/guides/bbdevs/acc101.rst             |   1 +
 drivers/baseband/acc101/rte_acc101_pmd.c | 157 +++++++++++++++++++++++++++++++
 2 files changed, 158 insertions(+)

diff --git a/doc/guides/bbdevs/acc101.rst b/doc/guides/bbdevs/acc101.rst
index ae27bf3..49f6c74 100644
--- a/doc/guides/bbdevs/acc101.rst
+++ b/doc/guides/bbdevs/acc101.rst
@@ -38,6 +38,7 @@ ACC101 5G/4G FEC PMD supports the following BBDEV capabilities:
    - ``RTE_BBDEV_LDPC_HQ_COMBINE_OUT_ENABLE`` :  provides an input for HARQ combining
    - ``RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_IN_ENABLE`` :  HARQ memory input is internal
    - ``RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_OUT_ENABLE`` :  HARQ memory output is internal
+   - ``RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_LOOPBACK`` :  loopback data to/from HARQ memory
    - ``RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_FILLERS`` :  HARQ memory includes the fillers bits
    - ``RTE_BBDEV_LDPC_DEC_SCATTER_GATHER`` :  supports scatter-gather for input/output data
    - ``RTE_BBDEV_LDPC_HARQ_6BIT_COMPRESSION`` :  supports compression of the HARQ input/output
diff --git a/drivers/baseband/acc101/rte_acc101_pmd.c b/drivers/baseband/acc101/rte_acc101_pmd.c
index 2861907..2009c1a 100644
--- a/drivers/baseband/acc101/rte_acc101_pmd.c
+++ b/drivers/baseband/acc101/rte_acc101_pmd.c
@@ -784,6 +784,7 @@
 				RTE_BBDEV_LDPC_HQ_COMBINE_IN_ENABLE |
 				RTE_BBDEV_LDPC_HQ_COMBINE_OUT_ENABLE |
 #ifdef ACC101_EXT_MEM
+				RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_LOOPBACK |
 				RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_IN_ENABLE |
 				RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_OUT_ENABLE |
 #endif
@@ -1730,6 +1731,157 @@ static inline uint32_t hq_index(uint32_t offset)
 	return return_descs;
 }
 
+static inline int
+harq_loopback(struct acc101_queue *q, struct rte_bbdev_dec_op *op,
+		uint16_t total_enqueued_cbs) {
+	struct acc101_fcw_ld *fcw;
+	union acc101_dma_desc *desc;
+	int next_triplet = 1;
+	struct rte_mbuf *hq_output_head, *hq_output;
+	uint16_t harq_dma_length_in, harq_dma_length_out;
+	uint16_t harq_in_length = op->ldpc_dec.harq_combined_input.length;
+	if (harq_in_length == 0) {
+		rte_bbdev_log(ERR, "Loopback of invalid null size\n");
+		return -EINVAL;
+	}
+
+	int h_comp = check_bit(op->ldpc_dec.op_flags,
+			RTE_BBDEV_LDPC_HARQ_6BIT_COMPRESSION
+			) ? 1 : 0;
+	if (h_comp == 1) {
+		harq_in_length = harq_in_length * 8 / 6;
+		harq_in_length = RTE_ALIGN(harq_in_length, 64);
+		harq_dma_length_in = harq_in_length * 6 / 8;
+	} else {
+		harq_in_length = RTE_ALIGN(harq_in_length, 64);
+		harq_dma_length_in = harq_in_length;
+	}
+	harq_dma_length_out = harq_dma_length_in;
+
+	bool ddr_mem_in = check_bit(op->ldpc_dec.op_flags,
+			RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_IN_ENABLE);
+	union acc101_harq_layout_data *harq_layout = q->d->harq_layout;
+	uint32_t harq_index = hq_index(ddr_mem_in ?
+			op->ldpc_dec.harq_combined_input.offset :
+			op->ldpc_dec.harq_combined_output.offset);
+
+	uint16_t desc_idx = ((q->sw_ring_head + total_enqueued_cbs)
+			& q->sw_ring_wrap_mask);
+	desc = q->ring_addr + desc_idx;
+	fcw = &desc->req.fcw_ld;
+	/* Set the FCW from loopback into DDR */
+	memset(fcw, 0, sizeof(struct acc101_fcw_ld));
+	fcw->FCWversion = ACC101_FCW_VER;
+	fcw->qm = 2;
+	fcw->Zc = 384;
+	if (harq_in_length < 16 * ACC101_N_ZC_1)
+		fcw->Zc = 16;
+	fcw->ncb = fcw->Zc * ACC101_N_ZC_1;
+	fcw->rm_e = 2;
+	fcw->hcin_en = 1;
+	fcw->hcout_en = 1;
+
+	rte_bbdev_log(DEBUG, "Loopback IN %d Index %d offset %d length %d %d\n",
+			ddr_mem_in, harq_index,
+			harq_layout[harq_index].offset, harq_in_length,
+			harq_dma_length_in);
+
+	if (ddr_mem_in && (harq_layout[harq_index].offset > 0)) {
+		fcw->hcin_size0 = harq_layout[harq_index].size0;
+		fcw->hcin_offset = harq_layout[harq_index].offset;
+		fcw->hcin_size1 = harq_in_length - fcw->hcin_offset;
+		harq_dma_length_in = (fcw->hcin_size0 + fcw->hcin_size1);
+		if (h_comp == 1)
+			harq_dma_length_in = harq_dma_length_in * 6 / 8;
+	} else {
+		fcw->hcin_size0 = harq_in_length;
+	}
+	harq_layout[harq_index].val = 0;
+	rte_bbdev_log(DEBUG, "Loopback FCW Config %d %d %d\n",
+			fcw->hcin_size0, fcw->hcin_offset, fcw->hcin_size1);
+	fcw->hcout_size0 = harq_in_length;
+	fcw->hcin_decomp_mode = h_comp;
+	fcw->hcout_comp_mode = h_comp;
+	fcw->gain_i = 1;
+	fcw->gain_h = 1;
+
+	/* Set the prefix of descriptor. This could be done at polling */
+	acc101_header_init(&desc->req);
+
+	/* Null LLR input for Decoder */
+	desc->req.data_ptrs[next_triplet].address =
+			q->lb_in_addr_iova;
+	desc->req.data_ptrs[next_triplet].blen = 2;
+	desc->req.data_ptrs[next_triplet].blkid = ACC101_DMA_BLKID_IN;
+	desc->req.data_ptrs[next_triplet].last = 0;
+	desc->req.data_ptrs[next_triplet].dma_ext = 0;
+	next_triplet++;
+
+	/* HARQ Combine input from either Memory interface */
+	if (!ddr_mem_in) {
+		next_triplet = acc101_dma_fill_blk_type_out(&desc->req,
+				op->ldpc_dec.harq_combined_input.data,
+				op->ldpc_dec.harq_combined_input.offset,
+				harq_dma_length_in,
+				next_triplet,
+				ACC101_DMA_BLKID_IN_HARQ);
+	} else {
+		desc->req.data_ptrs[next_triplet].address =
+				op->ldpc_dec.harq_combined_input.offset;
+		desc->req.data_ptrs[next_triplet].blen =
+				harq_dma_length_in;
+		desc->req.data_ptrs[next_triplet].blkid =
+				ACC101_DMA_BLKID_IN_HARQ;
+		desc->req.data_ptrs[next_triplet].dma_ext = 1;
+		next_triplet++;
+	}
+	desc->req.data_ptrs[next_triplet - 1].last = 1;
+	desc->req.m2dlen = next_triplet;
+
+	/* Dropped decoder hard output */
+	desc->req.data_ptrs[next_triplet].address =
+			q->lb_out_addr_iova;
+	desc->req.data_ptrs[next_triplet].blen = ACC101_BYTES_IN_WORD;
+	desc->req.data_ptrs[next_triplet].blkid = ACC101_DMA_BLKID_OUT_HARD;
+	desc->req.data_ptrs[next_triplet].last = 0;
+	desc->req.data_ptrs[next_triplet].dma_ext = 0;
+	next_triplet++;
+
+	/* HARQ Combine output to either Memory interface */
+	if (check_bit(op->ldpc_dec.op_flags,
+			RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_OUT_ENABLE
+			)) {
+		desc->req.data_ptrs[next_triplet].address =
+				op->ldpc_dec.harq_combined_output.offset;
+		desc->req.data_ptrs[next_triplet].blen =
+				harq_dma_length_out;
+		desc->req.data_ptrs[next_triplet].blkid =
+				ACC101_DMA_BLKID_OUT_HARQ;
+		desc->req.data_ptrs[next_triplet].dma_ext = 1;
+		next_triplet++;
+	} else {
+		hq_output_head = op->ldpc_dec.harq_combined_output.data;
+		hq_output = op->ldpc_dec.harq_combined_output.data;
+		next_triplet = acc101_dma_fill_blk_type_out(
+				&desc->req,
+				op->ldpc_dec.harq_combined_output.data,
+				op->ldpc_dec.harq_combined_output.offset,
+				harq_dma_length_out,
+				next_triplet,
+				ACC101_DMA_BLKID_OUT_HARQ);
+		/* HARQ output */
+		mbuf_append(hq_output_head, hq_output, harq_dma_length_out);
+		op->ldpc_dec.harq_combined_output.length =
+				harq_dma_length_out;
+	}
+	desc->req.data_ptrs[next_triplet - 1].last = 1;
+	desc->req.d2mlen = next_triplet - desc->req.m2dlen;
+	desc->req.op_addr = op;
+
+	/* One CB (one op) was successfully prepared to enqueue */
+	return 1;
+}
+
 /** Enqueue one decode operations for ACC101 device in CB mode */
 static inline int
 enqueue_ldpc_dec_one_op_cb(struct acc101_queue *q, struct rte_bbdev_dec_op *op,
@@ -1738,6 +1890,11 @@ static inline uint32_t hq_index(uint32_t offset)
 {
 	RTE_SET_USED(q_data);
 	int ret;
+	if (unlikely(check_bit(op->ldpc_dec.op_flags,
+			RTE_BBDEV_LDPC_INTERNAL_HARQ_MEMORY_LOOPBACK))) {
+		ret = harq_loopback(q, op, total_enqueued_cbs);
+		return ret;
+	}
 
 	union acc101_dma_desc *desc;
 	uint16_t desc_idx = ((q->sw_ring_head + total_enqueued_cbs)
-- 
1.8.3.1