chip/mt8192_scp: do not handle pending IPI interrupts

No need to handle pending IPI interrupts.

Reasons:
- Interrupts are level trigger in MT8192 SCP.  As long as the source
  interrupts persist, RV33 handles them eventually.
- task_trigger_irq() fires an additional GIPC_IN0 IRQ.  The former one
  will clear the interrupt source by writing GIPC_IN_CLR.  When the
  latter one is handling, RV33 crashed due to it cannot find the
  corresponding interrupt source.

BRANCH=none
BUG=b:163682416
TEST=1. cat - <<EOF >test.sh
    echo stop >/sys/class/remoteproc/remoteproc0/state

    while :; do
	dmesg -C

	echo start >/sys/class/remoteproc/remoteproc0/state
	sleep 1
	if dmesg | grep -q 'rpmsg send timeout'; then
	    break
	fi

	echo stop >/sys/class/remoteproc/remoteproc0/state
    done

    echo stop >/sys/class/remoteproc/remoteproc0/state
EOF
2. sh test.sh

Signed-off-by: Tzung-Bi Shih <tzungbi@chromium.org>
Change-Id: I2cc89a258a4ce218389799bbe1101ffc1375af8a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2373846
Reviewed-by: Ting Shen <phoenixshen@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2378954
Reviewed-by: Edward Hill <ecgh@chromium.org>
Commit-Queue: Edward Hill <ecgh@chromium.org>
Tested-by: Edward Hill <ecgh@chromium.org>

1 files changed, 1 insertions, 7 deletions

diff --git a/chip/mt8192_scp/ipi.c b/chip/mt8192_scp/ipi.c
index 2f67f7fa14..83d9fa8ebb 100644
--- a/chip/mt8192_scp/ipi.c
+++ b/chip/mt8192_scp/ipi.c
@@ -38,14 +38,8 @@ void ipi_disable_irq(void)
 
 void ipi_enable_irq(void)
 {
-	if (atomic_dec(&disable_irq_count, 1) == 1) {
-		int pending = SCP_GIPC_IN_SET;
-
+	if (atomic_dec(&disable_irq_count, 1) == 1)
 		set_int_mask(saved_int_mask);
-
-		if (init_done && pending)
-			task_trigger_irq(SCP_IRQ_GIPC_IN0);
-	}
 }
 
 static int ipi_is_busy(void)