Revert "task: Fix mutex_lock() assert (reland)"

This reverts commit 8d46141f4d45c65712a9ca7509b7b60128fa4d89.

Reason for revert: 

getting EC boot loop on volteer:
(note that you have to flash EC-RO to get this)

20-08-07 00:22:33.520 --- UART initialized after reboot ---
20-08-07 00:22:33.531 [Image: RO, volteer_1.1.9999-4284ce1  @caveh]
20-08-07 00:22:33.531 [Reset cause: reset-pin]
20-08-07 00:22:33.531 [0.005149 KB boot key mask 0]
20-08-07 00:22:33.543 [0.005438 init buttons]
20-08-07 00:22:33.543 [0.005669 VB Main]
20-08-07 00:22:33.543 [0.005872 VB Ping Cr50]
20-08-07 00:22:33.543 [0.007148 hash start 0x00040000 0x0002f61c]
20-08-07 00:22:33.833 [0.300169 hash done e4ddc3d0ffd015db085389d94faa38d3922e42290b6887baa8de3067ce846c13]
20-08-07 00:22:33.833 [0.300289 VB Verifying hash]
20-08-07 00:22:33.833 ��������������������������������EC\0\0 �������S��O�8Ӓ.B)h����0g΄l[0.317577 VB Received 0xec00]
20-08-07 00:22:33.850 [0.317899 Jumping to image RW]
20-08-07 00:22:33.850 
20-08-07 00:22:33.850 ASSERTION FAILURE '!in_interrupt_context() && task_start_called()' in mutex_lock() at core/cortex-m/task.c:868
20-08-07 00:22:33.861 
20-08-07 00:22:33.861 === HANDLER EXCEPTION: 00 ====== xPSR: 0000000a ===
20-08-07 00:22:33.861 r0 :00000364 r1 :100b6815 r2 :100b72ab r3 :100956bd
20-08-07 00:22:33.873 r4 :dead6663 r5 :00000364 r6 :200c1c20 r7 :00000001
20-08-07 00:22:33.873 r8 :00001388 r9 :100b4108 r10:100b4158 r11:00000013
20-08-07 00:22:33.884 r12:10095811 sp :200c0320 lr :200c1c20 pc :200c14f8
20-08-07 00:22:33.884 
20-08-07 00:22:33.884 cfsr = 0, shcsr = 70000, hfsr = 0, dfsr = 0
20-08-07 00:22:33.884 
20-08-07 00:22:33.884 =========== Process Stack Contents ===========
20-08-07 00:22:33.889 00000000: 100cfc00 00002a3d 00002751 00002731
20-08-07 00:22:33.901 00000010: 00002741 00002711 000027e1 00002791
20-08-07 00:22:33.901 00000020: 000027a1 000027b1 00002771 000027c1
20-08-07 00:22:33.901 00000030: 00002721 00002781 00002761 000027d1
20-08-07 00:22:33.906 
20-08-07 00:22:33.906 Rebooting...
20-08-07 00:22:33.996 
20-08-07 00:22:33.996 
20-08-07 00:22:33.996 --- UART initialized after reboot ---














Original change's description:
> task: Fix mutex_lock() assert (reland)
> 
> mutex_lock() must not be used in interrupt context. Add an assert
> to catch this.
> 
> Also assert task_start_called() since task ID is not valid
> before this.
> 
> Also remove an old assert since comparing id with TASK_ID_INVALID
> doesn't make sense.
> 
> This was first submitted as CL:2309057, then reverted by CL:2323704
> because it broke jump to RW (b/162302011). Fix this by adding check
> for task_start_called() to chip/npcx/flash.c and common/i2c_master.c.
> 
> BUG=b:160975910
> BRANCH=none
> TEST=boot AP, jump to RW
> 
> Signed-off-by: Edward Hill <ecgh@chromium.org>
> Change-Id: I070a265a95d2128643b536814e608509d81adbe3
> Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2335738
> Reviewed-by: Raul E Rangel <rrangel@chromium.org>
> Reviewed-by: Denis Brockus <dbrockus@chromium.org>

Bug: b:160975910
Change-Id: I9e37b1eac7344cddbd756fb45b130d7e0aee661b
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2341706
Reviewed-by: caveh jalali <caveh@chromium.org>
Commit-Queue: caveh jalali <caveh@chromium.org>
Tested-by: caveh jalali <caveh@chromium.org>

1 files changed, 1 insertions, 7 deletions

diff --git a/core/cortex-m/task.c b/core/cortex-m/task.c
index 61697d2684..75fbf99155 100644
--- a/core/cortex-m/task.c
+++ b/core/cortex-m/task.c
@@ -860,13 +860,7 @@ void mutex_lock(struct mutex *mtx)
 	uint32_t value;
 	uint32_t id = 1 << task_get_current();
 
-	/*
-	 * mutex_lock() must not be used in interrupt context (because we wait
-	 * if there is contention). Task ID is not valid before task_start()
-	 * (since current_task is scratchpad).
-	 */
-	ASSERT(!in_interrupt_context() && task_start_called());
-
+	ASSERT(id != TASK_ID_INVALID);
 	atomic_or(&mtx->waiters, id);
 
 	do {