[dpdk-dev] [PATCH 1/2] mempool/octeontx2: fix shift calculation

[pbhagavatula at marvell.com]

From: Pavan Nikhilesh <pbhagavatula at marvell.com>

Shift is used to generate an 8-bit saturate value from the current
aura used count. The shift value should be derived from the log2 of
block count if it is greater than 256 else the shift should be 0.

Fixes: 7bcc47cbe2fa ("mempool/octeontx2: add mempool alloc op")

Signed-off-by: Pavan Nikhilesh <pbhagavatula at marvell.com>
---
 drivers/mempool/octeontx2/otx2_mempool_ops.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mempool/octeontx2/otx2_mempool_ops.c b/drivers/mempool/octeontx2/otx2_mempool_ops.c
index 9ff71bcf6b..d827fd8c7b 100644
--- a/drivers/mempool/octeontx2/otx2_mempool_ops.c
+++ b/drivers/mempool/octeontx2/otx2_mempool_ops.c
@@ -611,7 +611,8 @@ npa_lf_aura_pool_pair_alloc(struct otx2_npa_lf *lf, const uint32_t block_size,
 	/* Update aura fields */
 	aura->pool_addr = pool_id;/* AF will translate to associated poolctx */
 	aura->ena = 1;
-	aura->shift = __builtin_clz(block_count) - 8;
+	aura->shift = rte_log2_u32(block_count);
+	aura->shift = aura->shift < 8 ? 0 : aura->shift - 8;
 	aura->limit = block_count;
 	aura->pool_caching = 1;
 	aura->err_int_ena = BIT(NPA_AURA_ERR_INT_AURA_ADD_OVER);
@@ -626,7 +627,8 @@ npa_lf_aura_pool_pair_alloc(struct otx2_npa_lf *lf, const uint32_t block_size,
 	pool->ena = 1;
 	pool->buf_size = block_size / OTX2_ALIGN;
 	pool->stack_max_pages = stack_size;
-	pool->shift = __builtin_clz(block_count) - 8;
+	pool->shift = rte_log2_u32(block_count);
+	pool->shift = pool->shift < 8 ? 0 : pool->shift - 8;
 	pool->ptr_start = 0;
 	pool->ptr_end = ~0;
 	pool->stack_caching = 1;
-- 
2.17.1