Commit 844bd696 authored by Adrian Hunter's avatar Adrian Hunter Committed by sanglipeng
Browse files

mmc: cqhci: Fix task clearing in CQE error recovery 

stable inclusion
from stable-v5.10.203
commit bb785011843ead83a9cb8dcd898371e7a177bed8
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9GXII

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=bb785011843ead83a9cb8dcd898371e7a177bed8



--------------------------------

[ 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: a4080225 ("mmc: cqhci: support for command queue enabled host")
Cc: stable@vger.kernel.org
Reported-by: default avatarKornel Dulęba <korneld@chromium.org>
Tested-by: default avatarKornel Dulęba <korneld@chromium.org>
Co-developed-by: default avatarKornel Dulęba <korneld@chromium.org>
Signed-off-by: default avatarKornel Dulęba <korneld@chromium.org>
Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Reviewed-by: default avatarAvri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20231103084720.6886-7-adrian.hunter@intel.com


Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarsanglipeng <sanglipeng1@jd.com>
parent d0e2d0b8

drivers/mmc/host/cqhci.c

+16 −16
Original line number Diff line number Diff line
@@ -1023,28 +1023,28 @@ 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));

	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);

		/* 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);

	}



	cqhci_halt(mmc, CQHCI_FINISH_HALT_TIMEOUT);



	if (!ok)

		cqhci_clear_all_tasks(mmc, CQHCI_CLEAR_TIMEOUT);



	cqhci_recover_mrqs(cq_host);