-----Original Message-----
From: Maxime Coquelin <maxime.coque...@redhat.com>
Sent: Thursday, November 3, 2022 7:10 AM
To: Vargas, Hernan <hernan.var...@intel.com>; dev@dpdk.org;
gak...@marvell.com; t...@redhat.com
Cc: Chautru, Nicolas <nicolas.chau...@intel.com>; Zhang, Qi Z
<qi.z.zh...@intel.com>
Subject: Re: [PATCH v7 1/1] baseband/acc100: add detection for deRM corner
cases
On 11/1/22 05:13, Hernan Vargas wrote:
Add function to detect if de-ratematch pre-processing is recommended
for SW corner cases.
Some specific 5GUL FEC corner cases may cause unintended back pressure
and in some cases a potential stability issue on the ACC100.
The PMD can detect such code block configuration and issue an info
message to the user.
Signed-off-by: Hernan Vargas <hernan.var...@intel.com>
---
drivers/baseband/acc/acc_common.h | 8 ++++
drivers/baseband/acc/rte_acc100_pmd.c | 55
+++++++++++++++++++++++++--
2 files changed, 60 insertions(+), 3 deletions(-)
diff --git a/drivers/baseband/acc/acc_common.h
b/drivers/baseband/acc/acc_common.h
index eae7eab4e9..6213b0b61e 100644
--- a/drivers/baseband/acc/acc_common.h
+++ b/drivers/baseband/acc/acc_common.h
@@ -123,6 +123,14 @@
#define ACC_HARQ_ALIGN_64B 64
#define ACC_MAX_ZC 384
+/* De-ratematch code rate limitation for recommended operation */
+#define ACC_LIM_03 2 /* 0.03 */ #define ACC_LIM_09 6 /* 0.09 */
+#define ACC_LIM_14 9 /* 0.14 */ #define ACC_LIM_21 14 /* 0.21 */
+#define ACC_LIM_31 20 /* 0.31 */ #define ACC_MAX_E (128 * 1024 - 2)
+
/* Helper macro for logging */
#define rte_acc_log(level, fmt, ...) \
rte_log(RTE_LOG_ ## level, RTE_LOG_NOTICE, fmt "\n", \ diff --git
a/drivers/baseband/acc/rte_acc100_pmd.c
b/drivers/baseband/acc/rte_acc100_pmd.c
index 23bc5d25bb..47609f95b7 100644
--- a/drivers/baseband/acc/rte_acc100_pmd.c
+++ b/drivers/baseband/acc/rte_acc100_pmd.c
@@ -756,6 +756,14 @@ acc100_queue_setup(struct rte_bbdev *dev,
uint16_t queue_id,
ret = -ENOMEM;
goto free_lb_out;
}
+ q->derm_buffer = rte_zmalloc_socket(dev->device->driver->name,
+ RTE_BBDEV_TURBO_MAX_CB_SIZE * 10,
+ RTE_CACHE_LINE_SIZE, conf->socket);
+ if (q->derm_buffer == NULL) {
+ rte_bbdev_log(ERR, "Failed to allocate derm_buffer memory");
+ ret = -ENOMEM;
+ goto free_companion_ring_addr;
+ }
/*
* Software queue ring wraps synchronously with the HW when it
reaches @@ -776,7 +784,7 @@ acc100_queue_setup(struct rte_bbdev *dev,
uint16_t queue_id,
q_idx = acc100_find_free_queue_idx(dev, conf);
if (q_idx == -1) {
ret = -EINVAL;
- goto free_companion_ring_addr;
+ goto free_derm_buffer;
}
q->qgrp_id = (q_idx >> ACC100_GRP_ID_SHIFT) & 0xF; @@ -804,6
+812,9
@@ acc100_queue_setup(struct rte_bbdev *dev, uint16_t queue_id,
dev->data->queues[queue_id].queue_private = q;
return 0;
+free_derm_buffer:
+ rte_free(q->derm_buffer);
+ q->derm_buffer = NULL;
free_companion_ring_addr:
rte_free(q->companion_ring_addr);
q->companion_ring_addr = NULL;
@@ -890,6 +901,7 @@ acc100_queue_release(struct rte_bbdev *dev,
uint16_t q_id)
/* Mark the Queue as un-assigned */
d->q_assigned_bit_map[q->qgrp_id] &= (0xFFFFFFFFFFFFFFFF -
(uint64_t) (1 << q->aq_id));
+ rte_free(q->derm_buffer);
rte_free(q->companion_ring_addr);
rte_free(q->lb_in);
rte_free(q->lb_out);
@@ -3111,10 +3123,41 @@ harq_loopback(struct acc_queue *q, struct
rte_bbdev_dec_op *op,
return 1;
}
+/* Assess whether a work around is recommended for the deRM corner
+cases */ static inline bool derm_workaround_recommended(struct
+rte_bbdev_op_ldpc_dec *ldpc_dec, struct acc_queue *q) {
+ if (!is_acc100(q))
+ return false;
+ int32_t e = ldpc_dec->cb_params.e;
+ int q_m = ldpc_dec->q_m;
+ int z_c = ldpc_dec->z_c;
+ int K = (ldpc_dec->basegraph == 1 ? ACC_K_ZC_1 : ACC_K_ZC_2) * z_c;
+ bool recommended = false;
+
+ if (ldpc_dec->basegraph == 1) {
+ if ((q_m == 4) && (z_c >= 320) && (e * ACC_LIM_31 > K * 64))
+ recommended = true;
+ else if ((e * ACC_LIM_21 > K * 64))
+ recommended = true;
+ } else {
+ if (q_m <= 2) {
+ if ((z_c >= 208) && (e * ACC_LIM_09 > K * 64))
+ recommended = true;
+ else if ((z_c < 208) && (e * ACC_LIM_03 > K * 64))
+ recommended = true;
+ } else if (e * ACC_LIM_14 > K * 64)
+ recommended = true;
+ }
+
+ return recommended;
+}
+
/** Enqueue one decode operations for ACC100 device in CB mode */
static inline int
enqueue_ldpc_dec_one_op_cb(struct acc_queue *q, struct
rte_bbdev_dec_op *op,
- uint16_t total_enqueued_cbs, bool same_op)
+ uint16_t total_enqueued_cbs, bool same_op,
+ struct rte_bbdev_queue_data *q_data)
{
int ret;
if (unlikely(check_bit(op->ldpc_dec.op_flags,
@@ -3168,6 +3211,12 @@ enqueue_ldpc_dec_one_op_cb(struct acc_queue
*q, struct rte_bbdev_dec_op *op,
} else {
struct acc_fcw_ld *fcw;
uint32_t seg_total_left;
+
+ if (derm_workaround_recommended(&op->ldpc_dec, q)) {
+ RTE_SET_USED(q_data);
Why do we need q_data if it is not being used?
