From a11fa2be6d1564375dc57530680268ad569c2632 Mon Sep 17 00:00:00 2001 From: Michael Chan Date: Sun, 15 May 2016 03:04:47 -0400 Subject: [PATCH] bnxt_en: Improve the delay logic for firmware response. The current code has 2 problems: 1. The maximum wait time is not long enough. It is about 60% of the duration specified by the firmware. It is calling usleep_range(600, 800) for every 1 msec we are supposed to wait. 2. The granularity of the delay is too coarse. Many simple firmware commands finish in 25 usec or less. We fix these 2 issues by multiplying the original 1 msec loop counter by 40 and calling usleep_range(25, 40) for each iteration. There is also a second delay loop to wait for the last DMA word to complete. This delay loop should be a very short 5 usec wait. This change results in much faster bring-up/down time: Before the patch: time ip link set p4p1 up real 0m0.120s user 0m0.001s sys 0m0.009s After the patch: time ip link set p4p1 up real 0m0.030s user 0m0.000s sys 0m0.010s Signed-off-by: Michael Chan Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 1171ad14d323..e20c258775ed 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -2780,7 +2780,7 @@ void bnxt_hwrm_cmd_hdr_init(struct bnxt *bp, void *request, u16 req_type, static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, int timeout, bool silent) { - int i, intr_process, rc; + int i, intr_process, rc, tmo_count; struct input *req = msg; u32 *data = msg; __le32 *resp_len, *valid; @@ -2809,11 +2809,12 @@ static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, timeout = DFLT_HWRM_CMD_TIMEOUT; i = 0; + tmo_count = timeout * 40; if (intr_process) { /* Wait until hwrm response cmpl interrupt is processed */ while (bp->hwrm_intr_seq_id != HWRM_SEQ_ID_INVALID && - i++ < timeout) { - usleep_range(600, 800); + i++ < tmo_count) { + usleep_range(25, 40); } if (bp->hwrm_intr_seq_id != HWRM_SEQ_ID_INVALID) { @@ -2824,15 +2825,15 @@ static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, } else { /* Check if response len is updated */ resp_len = bp->hwrm_cmd_resp_addr + HWRM_RESP_LEN_OFFSET; - for (i = 0; i < timeout; i++) { + for (i = 0; i < tmo_count; i++) { len = (le32_to_cpu(*resp_len) & HWRM_RESP_LEN_MASK) >> HWRM_RESP_LEN_SFT; if (len) break; - usleep_range(600, 800); + usleep_range(25, 40); } - if (i >= timeout) { + if (i >= tmo_count) { netdev_err(bp->dev, "Error (timeout: %d) msg {0x%x 0x%x} len:%d\n", timeout, le16_to_cpu(req->req_type), le16_to_cpu(req->seq_id), *resp_len); @@ -2841,13 +2842,13 @@ static int bnxt_hwrm_do_send_msg(struct bnxt *bp, void *msg, u32 msg_len, /* Last word of resp contains valid bit */ valid = bp->hwrm_cmd_resp_addr + len - 4; - for (i = 0; i < timeout; i++) { + for (i = 0; i < 5; i++) { if (le32_to_cpu(*valid) & HWRM_RESP_VALID_MASK) break; - usleep_range(600, 800); + udelay(1); } - if (i >= timeout) { + if (i >= 5) { netdev_err(bp->dev, "Error (timeout: %d) msg {0x%x 0x%x} len:%d v:%d\n", timeout, le16_to_cpu(req->req_type), le16_to_cpu(req->seq_id), len, *valid); -- 2.20.1