From 6b294b8efedaa7cf7507154148e2c79766ad6f96 Mon Sep 17 00:00:00 2001 From: Robert Stonehouse Date: Wed, 9 Oct 2013 11:52:48 +0100 Subject: [PATCH] sfc: Poll for MCDI completion once before timeout occurs There is an as-yet unexplained bug that sometimes prevents (or delays) the driver seeing the completion event for a completed MCDI request on the SFC9120. The requested configuration change will have happened but the driver assumes it to have failed, and this can result in further failures. We can mitigate this by polling for completion after unsuccessfully waiting for an event. Fixes: 8127d661e77f ('sfc: Add support for Solarflare SFC9100 family') Signed-off-by: Ben Hutchings --- drivers/net/ethernet/sfc/mcdi.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c index 9f26e46ee283..4b0bd8a1514d 100644 --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -630,6 +630,16 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen, rc = efx_mcdi_await_completion(efx); if (rc != 0) { + netif_err(efx, hw, efx->net_dev, + "MC command 0x%x inlen %d mode %d timed out\n", + cmd, (int)inlen, mcdi->mode); + + if (mcdi->mode == MCDI_MODE_EVENTS && efx_mcdi_poll_once(efx)) { + netif_err(efx, hw, efx->net_dev, + "MCDI request was completed without an event\n"); + rc = 0; + } + /* Close the race with efx_mcdi_ev_cpl() executing just too late * and completing a request we've just cancelled, by ensuring * that the seqno check therein fails. @@ -638,11 +648,9 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen, ++mcdi->seqno; ++mcdi->credits; spin_unlock_bh(&mcdi->iface_lock); + } - netif_err(efx, hw, efx->net_dev, - "MC command 0x%x inlen %d mode %d timed out\n", - cmd, (int)inlen, mcdi->mode); - } else { + if (rc == 0) { size_t hdr_len, data_len; /* At the very least we need a memory barrier here to ensure -- 2.30.2