diff options
| author | Kelvin Cao <kelvin.cao@microchip.com> | 2018-12-10 17:12:20 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-27 14:46:07 +0100 |
| commit | 336384d871a9797a620063158c3d80988ea0cc47 (patch) | |
| tree | 7a3c7f5668628fa9672776024b47747b98f6fd06 /drivers/pci | |
| parent | 0c52e16253a5d6d810696a647107ea55909708f2 (diff) | |
switchtec: Remove immediate status check after submitting MRPC command
[ Upstream commit 526180408b815aa7b96fd48bd23cdd33ef04e38e ]
After submitting a Firmware Download MRPC command, Switchtec firmware will
delay Management EP BAR MemRd TLP responses by more than 10ms. This is a
firmware limitation. Delayed MemRd completions are a problem for systems
with a low Completion Timeout (CTO).
The current driver checks the MRPC status immediately after submitting an
MRPC command, which results in a delayed MemRd completion that may cause a
Completion Timeout.
Remove the immediate status check and rely on the check after receiving an
interrupt or timing out.
This is only a software workaround to the READ issue and a proper fix of
this should be done in firmware.
Fixes: 080b47def5e5 ("MicroSemi Switchtec management interface driver")
Signed-off-by: Kelvin Cao <kelvin.cao@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/switch/switchtec.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c index 0941555b84a5..73dba2739849 100644 --- a/drivers/pci/switch/switchtec.c +++ b/drivers/pci/switch/switchtec.c @@ -399,10 +399,6 @@ static void mrpc_cmd_submit(struct switchtec_dev *stdev) stuser->data, stuser->data_len); iowrite32(stuser->cmd, &stdev->mmio_mrpc->cmd); - stuser->status = ioread32(&stdev->mmio_mrpc->status); - if (stuser->status != SWITCHTEC_MRPC_STATUS_INPROGRESS) - mrpc_complete_cmd(stdev); - schedule_delayed_work(&stdev->mrpc_timeout, msecs_to_jiffies(500)); } |