diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c index 726969cfcaec..d8193d9577bb 100644 --- a/drivers/net/wireless/ath/ath12k/hal.c +++ b/drivers/net/wireless/ath/ath12k/hal.c @@ -2178,7 +2178,11 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) if (srng->ring_dir == HAL_SRNG_DIR_SRC) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; - *srng->u.src_ring.hp_addr = srng->u.src_ring.hp; + /* Make sure descriptor is written before updating the + * head pointer. + */ + dma_wmb(); + WRITE_ONCE(*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); } else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp; @@ -2187,6 +2191,10 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng) if (srng->ring_dir == HAL_SRNG_DIR_SRC) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; + /* Assume implementation use an MMIO write accessor + * which has the required wmb() so that the descriptor + * is written before the updating the head pointer. + */ ath12k_hif_write32(ab, (unsigned long)srng->u.src_ring.hp_addr - (unsigned long)ab->mem,