5.4-stable review patch. If anyone has any objections, please let me know.
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From: Adrian Hunter adrian.hunter@intel.com
[ Upstream commit 1de1b77982e1a1df9707cb11f9b1789e6b8919d4 ]
If a task completion notification (TCN) is received when there is no outstanding task, the cqhci driver issues a "spurious TCN" warning. This was observed to happen right after CQE error recovery.
When an error interrupt is received the driver runs recovery logic. It halts the controller, clears all pending tasks, and then re-enables it. On some platforms, like Intel Jasper Lake, a stale task completion event was observed, regardless of the CQHCI_CLEAR_ALL_TASKS bit being set.
This results in either: a) Spurious TC completion event for an empty slot. b) Corrupted data being passed up the stack, as a result of premature completion for a newly added task.
Rather than add a quirk for affected controllers, ensure tasks are cleared by toggling CQHCI_ENABLE, which would happen anyway if cqhci_clear_all_tasks() timed out. This is simpler and should be safe and effective for all controllers.
Fixes: a4080225f51d ("mmc: cqhci: support for command queue enabled host") Cc: stable@vger.kernel.org Reported-by: Kornel Dulęba korneld@chromium.org Tested-by: Kornel Dulęba korneld@chromium.org Co-developed-by: Kornel Dulęba korneld@chromium.org Signed-off-by: Kornel Dulęba korneld@chromium.org Signed-off-by: Adrian Hunter adrian.hunter@intel.com Reviewed-by: Avri Altman avri.altman@wdc.com Link: https://lore.kernel.org/r/20231103084720.6886-7-adrian.hunter@intel.com Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/host/cqhci.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/drivers/mmc/host/cqhci.c b/drivers/mmc/host/cqhci.c index 29440fd4ff099..10b36b156562a 100644 --- a/drivers/mmc/host/cqhci.c +++ b/drivers/mmc/host/cqhci.c @@ -1011,28 +1011,28 @@ static void cqhci_recovery_finish(struct mmc_host *mmc)
ok = cqhci_halt(mmc, CQHCI_FINISH_HALT_TIMEOUT);
- if (!cqhci_clear_all_tasks(mmc, CQHCI_CLEAR_TIMEOUT)) - ok = false; - /* * The specification contradicts itself, by saying that tasks cannot be * cleared if CQHCI does not halt, but if CQHCI does not halt, it should * be disabled/re-enabled, but not to disable before clearing tasks. * Have a go anyway. */ - if (!ok) { - pr_debug("%s: cqhci: disable / re-enable\n", mmc_hostname(mmc)); - cqcfg = cqhci_readl(cq_host, CQHCI_CFG); - cqcfg &= ~CQHCI_ENABLE; - cqhci_writel(cq_host, cqcfg, CQHCI_CFG); - cqcfg |= CQHCI_ENABLE; - cqhci_writel(cq_host, cqcfg, CQHCI_CFG); - /* Be sure that there are no tasks */ - ok = cqhci_halt(mmc, CQHCI_FINISH_HALT_TIMEOUT); - if (!cqhci_clear_all_tasks(mmc, CQHCI_CLEAR_TIMEOUT)) - ok = false; - WARN_ON(!ok); - } + if (!cqhci_clear_all_tasks(mmc, CQHCI_CLEAR_TIMEOUT)) + ok = false; + + /* Disable to make sure tasks really are cleared */ + cqcfg = cqhci_readl(cq_host, CQHCI_CFG); + cqcfg &= ~CQHCI_ENABLE; + cqhci_writel(cq_host, cqcfg, CQHCI_CFG); + + cqcfg = cqhci_readl(cq_host, CQHCI_CFG); + cqcfg |= CQHCI_ENABLE; + cqhci_writel(cq_host, cqcfg, CQHCI_CFG); + + cqhci_halt(mmc, CQHCI_FINISH_HALT_TIMEOUT); + + if (!ok) + cqhci_clear_all_tasks(mmc, CQHCI_CLEAR_TIMEOUT);
cqhci_recover_mrqs(cq_host);