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Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-1014-Revert-mailbox-avoid-timer-start-from-callback.patch')
-rw-r--r--target/linux/bcm27xx/patches-5.4/950-1014-Revert-mailbox-avoid-timer-start-from-callback.patch60
1 files changed, 0 insertions, 60 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-1014-Revert-mailbox-avoid-timer-start-from-callback.patch b/target/linux/bcm27xx/patches-5.4/950-1014-Revert-mailbox-avoid-timer-start-from-callback.patch
deleted file mode 100644
index 849bdd192e..0000000000
--- a/target/linux/bcm27xx/patches-5.4/950-1014-Revert-mailbox-avoid-timer-start-from-callback.patch
+++ /dev/null
@@ -1,60 +0,0 @@
-From 2b7fcd18b15d9cc7b2e68deb77f4e0acfa904c41 Mon Sep 17 00:00:00 2001
-From: Phil Elwell <phil@raspberrypi.com>
-Date: Tue, 3 Nov 2020 10:13:48 +0000
-Subject: [PATCH] Revert "mailbox: avoid timer start from callback"
-
-This reverts commit 6dc15642c8b830d384fd3e6c9ea63144202b8932.
-
-The Pi 400 shutdown/poweroff mechanism relies on being able to set
-a GPIO on the expander in the pm_power_off handler, something that
-requires two mailbox calls - GET_GPIO_STATE and SET_GPIO_STATE. A
-recent kernel change introduces a reasonable possibility that the
-GET call doesn't completes, and bisecting led to a commit from
-October that changes the timer usage of the mailbox.
-
-My theory is that there is a race condition in the new code that breaks
-the poll timer, but that it normally goes unnoticed because subsequent
-mailbox activity wakes it up again. The power-off mailbox calls happen
-at a time when other subsystems have been shut down, so if one of them
-fails then there is nothing to allow it to recover.
-
-Revert 6dc15642 as (at least) a workaround.
-
-See: https://github.com/raspberrypi/linux/issues/3941
-
-Signed-off-by: Phil Elwell <phil@raspberrypi.com>
----
- drivers/mailbox/mailbox.c | 12 +++++-------
- 1 file changed, 5 insertions(+), 7 deletions(-)
-
---- a/drivers/mailbox/mailbox.c
-+++ b/drivers/mailbox/mailbox.c
-@@ -82,12 +82,9 @@ static void msg_submit(struct mbox_chan
- exit:
- spin_unlock_irqrestore(&chan->lock, flags);
-
-- /* kick start the timer immediately to avoid delays */
-- if (!err && (chan->txdone_method & TXDONE_BY_POLL)) {
-- /* but only if not already active */
-- if (!hrtimer_active(&chan->mbox->poll_hrt))
-- hrtimer_start(&chan->mbox->poll_hrt, 0, HRTIMER_MODE_REL);
-- }
-+ if (!err && (chan->txdone_method & TXDONE_BY_POLL))
-+ /* kick start the timer immediately to avoid delays */
-+ hrtimer_start(&chan->mbox->poll_hrt, 0, HRTIMER_MODE_REL);
- }
-
- static void tx_tick(struct mbox_chan *chan, int r)
-@@ -125,10 +122,11 @@ static enum hrtimer_restart txdone_hrtim
- struct mbox_chan *chan = &mbox->chans[i];
-
- if (chan->active_req && chan->cl) {
-- resched = true;
- txdone = chan->mbox->ops->last_tx_done(chan);
- if (txdone)
- tx_tick(chan, 0);
-+ else
-+ resched = true;
- }
- }
-