From 880f8f99d12ca89d3ec76f688e0d92612054cbb1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 23 May 2020 12:46:49 -0700 Subject: bnx2x: allow bnx2x_bsc_read() to schedule bnx2x_warpcore_read_sfp_module_eeprom() can call bnx2x_bsc_read() three times before giving up. This causes latency blips of at least 31 ms (58 ms being reported by our teams) Convert the long lasting loops of udelay() to usleep_range() ones, and breaks the loops on precise time tracking. Signed-off-by: Eric Dumazet Cc: Ariel Elior Cc: Sudarsana Kalluru Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c | 26 ++++++++++++++---------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'drivers/net/ethernet/broadcom/bnx2x') diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c index 517caedc0a87..1426c691c7c4 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c @@ -3085,6 +3085,7 @@ static int bnx2x_bsc_read(struct link_params *params, u8 xfer_cnt, u32 *data_array) { + u64 t0, delta; u32 val, i; int rc = 0; @@ -3114,17 +3115,18 @@ static int bnx2x_bsc_read(struct link_params *params, REG_WR(bp, MCP_REG_MCPR_IMC_COMMAND, val); /* Poll for completion */ - i = 0; + t0 = ktime_get_ns(); val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); while (((val >> MCPR_IMC_COMMAND_IMC_STATUS_BITSHIFT) & 0x3) != 1) { - udelay(10); - val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); - if (i++ > 1000) { - DP(NETIF_MSG_LINK, "wr 0 byte timed out after %d try\n", - i); + delta = ktime_get_ns() - t0; + if (delta > 10 * NSEC_PER_MSEC) { + DP(NETIF_MSG_LINK, "wr 0 byte timed out after %Lu ns\n", + delta); rc = -EFAULT; break; } + usleep_range(10, 20); + val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); } if (rc == -EFAULT) return rc; @@ -3138,16 +3140,18 @@ static int bnx2x_bsc_read(struct link_params *params, REG_WR(bp, MCP_REG_MCPR_IMC_COMMAND, val); /* Poll for completion */ - i = 0; + t0 = ktime_get_ns(); val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); while (((val >> MCPR_IMC_COMMAND_IMC_STATUS_BITSHIFT) & 0x3) != 1) { - udelay(10); - val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); - if (i++ > 1000) { - DP(NETIF_MSG_LINK, "rd op timed out after %d try\n", i); + delta = ktime_get_ns() - t0; + if (delta > 10 * NSEC_PER_MSEC) { + DP(NETIF_MSG_LINK, "rd op timed out after %Lu ns\n", + delta); rc = -EFAULT; break; } + usleep_range(10, 20); + val = REG_RD(bp, MCP_REG_MCPR_IMC_COMMAND); } if (rc == -EFAULT) return rc; -- cgit v1.2.3