| Vijayenthiran Subramaniam | dfda93d | 2020-07-23 12:53:35 +0530 | [diff] [blame] | 1 | From f1cd888433a0f04806f0074ea3572eb79f781274 Mon Sep 17 00:00:00 2001 |
| 2 | From: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com> |
| 3 | Date: Wed, 23 Oct 2019 11:48:02 +0530 |
| 4 | Subject: [PATCH] [HACK]: spinlock: send explicit event after store release |
| 5 | instruction |
| 6 | |
| 7 | stlr instruction in the spin_unlock function is expected to send an |
| 8 | implicit event to all CPU cores. In a cross chip scenario, FVP has |
| 9 | stability issues while sending this implicit event across chips. |
| 10 | To avoid the stability issues, add sev instruction which sends explicit |
| 11 | events to all cores. Explicit events are propagated across chips without |
| 12 | any stability issues. |
| 13 | |
| 14 | Change-Id: I94db4f940e98f9b60f4120d0bde4930f9d31440c |
| 15 | Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com> |
| 16 | --- |
| 17 | lib/locks/exclusive/aarch64/spinlock.S | 1 + |
| 18 | 1 file changed, 1 insertion(+) |
| 19 | |
| 20 | diff --git a/lib/locks/exclusive/aarch64/spinlock.S b/lib/locks/exclusive/aarch64/spinlock.S |
| 21 | index e941b8a34..2c01a3bee 100644 |
| 22 | --- a/lib/locks/exclusive/aarch64/spinlock.S |
| 23 | +++ b/lib/locks/exclusive/aarch64/spinlock.S |
| 24 | @@ -71,5 +71,6 @@ endfunc spin_lock |
| 25 | */ |
| 26 | func spin_unlock |
| 27 | stlr wzr, [x0] |
| 28 | + sev |
| 29 | ret |
| 30 | endfunc spin_unlock |
| 31 | -- |
| 32 | 2.17.1 |
| 33 | |