From da34fad65d84c3bb19eb1e6e5d143d4bf1454fba Mon Sep 17 00:00:00 2001 From: Michal Kazior Date: Wed, 16 Jul 2014 15:01:39 +0200 Subject: [PATCH] ath10k: workaround boot issues with KVM/PCI-passthrough Apparently iomap writes that unmask CE irqs aren't propagated properly sometimes. Before failing try to poll for the control response message as it may have been delivered without an interrupt. Signed-off-by: Michal Kazior Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/ath10k/htc.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath10k/htc.c b/drivers/net/wireless/ath/ath10k/htc.c index e493db4b4a41..5fdc40d3b378 100644 --- a/drivers/net/wireless/ath/ath10k/htc.c +++ b/drivers/net/wireless/ath/ath10k/htc.c @@ -546,7 +546,7 @@ static u8 ath10k_htc_get_credit_allocation(struct ath10k_htc *htc, int ath10k_htc_wait_target(struct ath10k_htc *htc) { - int status = 0; + int i, status = 0; struct ath10k_htc_svc_conn_req conn_req; struct ath10k_htc_svc_conn_resp conn_resp; struct ath10k_htc_msg *msg; @@ -556,10 +556,26 @@ int ath10k_htc_wait_target(struct ath10k_htc *htc) status = wait_for_completion_timeout(&htc->ctl_resp, ATH10K_HTC_WAIT_TIMEOUT_HZ); - if (status <= 0) { + if (status == 0) { + /* Workaround: In some cases the PCI HIF doesn't + * receive interrupt for the control response message + * even if the buffer was completed. It is suspected + * iomap writes unmasking PCI CE irqs aren't propagated + * properly in KVM PCI-passthrough sometimes. + */ + ath10k_warn("failed to receive control response completion, polling..\n"); + + for (i = 0; i < CE_COUNT; i++) + ath10k_hif_send_complete_check(htc->ar, i, 1); + + status = wait_for_completion_timeout(&htc->ctl_resp, + ATH10K_HTC_WAIT_TIMEOUT_HZ); + if (status == 0) status = -ETIMEDOUT; + } + if (status < 0) { ath10k_err("ctl_resp never came in (%d)\n", status); return status; } -- 2.20.1