diff options
author | Jonas Dreßler <verdre@v0yd.nl> | 2021-10-11 16:32:23 +0300 |
---|---|---|
committer | Kalle Valo <kvalo@codeaurora.org> | 2021-10-18 15:29:51 +0300 |
commit | e5f4eb8223aa740237cd463246a7debcddf4eda1 (patch) | |
tree | 7e88fde9a1a94a975ed5c7d6a34689720c4ea41f /drivers/net/wireless/marvell/mwifiex | |
parent | ff1cc2fa3055ee4c83839f38b74b4ee370a2291c (diff) | |
download | linux-e5f4eb8223aa740237cd463246a7debcddf4eda1.tar.xz |
mwifiex: Read a PCI register after writing the TX ring write pointer
On the 88W8897 PCIe+USB card the firmware randomly crashes after setting
the TX ring write pointer. The issue is present in the latest firmware
version 15.68.19.p21 of the PCIe+USB card.
Those firmware crashes can be worked around by reading any PCI register
of the card after setting that register, so read the PCI_VENDOR_ID
register here. The reason this works is probably because we keep the bus
from entering an ASPM state for a bit longer, because that's what causes
the cards firmware to crash.
This fixes a bug where during RX/TX traffic and with ASPM L1 substates
enabled (the specific substates where the issue happens appear to be
platform dependent), the firmware crashes and eventually a command
timeout appears in the logs.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=109681
Cc: stable@vger.kernel.org
Signed-off-by: Jonas Dreßler <verdre@v0yd.nl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211011133224.15561-2-verdre@v0yd.nl
Diffstat (limited to 'drivers/net/wireless/marvell/mwifiex')
-rw-r--r-- | drivers/net/wireless/marvell/mwifiex/pcie.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c index c6ccce426b49..641fa539de1f 100644 --- a/drivers/net/wireless/marvell/mwifiex/pcie.c +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c @@ -1490,6 +1490,14 @@ mwifiex_pcie_send_data(struct mwifiex_adapter *adapter, struct sk_buff *skb, ret = -1; goto done_unmap; } + + /* The firmware (latest version 15.68.19.p21) of the 88W8897 PCIe+USB card + * seems to crash randomly after setting the TX ring write pointer when + * ASPM powersaving is enabled. A workaround seems to be keeping the bus + * busy by reading a random register afterwards. + */ + mwifiex_read_reg(adapter, PCI_VENDOR_ID, &rx_val); + if ((mwifiex_pcie_txbd_not_full(card)) && tx_param->next_pkt_len) { /* have more packets and TxBD still can hold more */ |