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Diffstat (limited to 'target/linux/layerscape/patches-5.4/802-can-0026-can-flexcan-fix-deadlock-when-using-self-wakeup.patch')
-rw-r--r--target/linux/layerscape/patches-5.4/802-can-0026-can-flexcan-fix-deadlock-when-using-self-wakeup.patch62
1 files changed, 0 insertions, 62 deletions
diff --git a/target/linux/layerscape/patches-5.4/802-can-0026-can-flexcan-fix-deadlock-when-using-self-wakeup.patch b/target/linux/layerscape/patches-5.4/802-can-0026-can-flexcan-fix-deadlock-when-using-self-wakeup.patch
deleted file mode 100644
index 2d55cb9401..0000000000
--- a/target/linux/layerscape/patches-5.4/802-can-0026-can-flexcan-fix-deadlock-when-using-self-wakeup.patch
+++ /dev/null
@@ -1,62 +0,0 @@
-From 59876225748221d7ebbdb9c892a2086420ddd80d Mon Sep 17 00:00:00 2001
-From: Sean Nyekjaer <sean@geanix.com>
-Date: Thu, 14 Nov 2019 19:56:28 +0800
-Subject: [PATCH] can: flexcan: fix deadlock when using self wakeup
-
-When suspending, when there is still can traffic on the interfaces the
-flexcan immediately wakes the platform again. As it should :-). But it
-throws this error msg:
-[ 3169.378661] PM: noirq suspend of devices failed
-
-On the way down to suspend the interface that throws the error message does
-call flexcan_suspend but fails to call flexcan_noirq_suspend. That means the
-flexcan_enter_stop_mode is called, but on the way out of suspend the driver
-only calls flexcan_resume and skips flexcan_noirq_resume, thus it doesn't call
-flexcan_exit_stop_mode. This leaves the flexcan in stop mode, and with the
-current driver it can't recover from this even with a soft reboot, it requires
-a hard reboot.
-
-This patch can fix deadlock when using self wakeup, it happenes to be
-able to fix another issue that frames out-of-order in first IRQ handler
-run after wakeup.
-
-In wakeup case, after system resume, frames received out-of-order,the
-problem is wakeup latency from frame reception to IRQ handler is much
-bigger than the counter overflow. This means it's impossible to sort the
-CAN frames by timestamp. The reason is that controller exits stop mode
-during noirq resume, then it can receive the frame immediately. If
-noirq reusme stage consumes much time, it will extend interrupt response
-time.
-
-Fixes: de3578c198c6 ("can: flexcan: add self wakeup support")
-Signed-off-by: Sean Nyekjaer <sean@geanix.com>
-Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
----
- drivers/net/can/flexcan.c | 9 +++++++--
- 1 file changed, 7 insertions(+), 2 deletions(-)
-
---- a/drivers/net/can/flexcan.c
-+++ b/drivers/net/can/flexcan.c
-@@ -137,8 +137,7 @@
- (FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
- #define FLEXCAN_ESR_ALL_INT \
- (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
-- FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT | \
-- FLEXCAN_ESR_WAK_INT)
-+ FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
-
- /* FLEXCAN Bit Timing register (CBT) bits */
- #define FLEXCAN_CBT_BTF BIT(31)
-@@ -1062,6 +1061,12 @@ static irqreturn_t flexcan_irq(int irq,
-
- reg_esr = priv->read(&regs->esr);
-
-+ /* ACK wakeup interrupt */
-+ if (reg_esr & FLEXCAN_ESR_WAK_INT) {
-+ handled = IRQ_HANDLED;
-+ priv->write(reg_esr & FLEXCAN_ESR_WAK_INT, &regs->esr);
-+ }
-+
- /* ACK all bus error and state change IRQ sources */
- if (reg_esr & FLEXCAN_ESR_ALL_INT) {
- handled = IRQ_HANDLED;