From 0be70439f2dcf4a2048e4b02f23f2c239b35a110 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <deathsimple@vodafone.de>
Date: Wed, 7 Mar 2012 11:28:57 +0100
Subject: drm/radeon: fix a semaphore deadlock on pre cayman asics
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Git-commit: 0be70439f2dcf4a2048e4b02f23f2c239b35a110
Patch-mainline: v3.3-rc7

The out of order execution of semaphore commands on
pre cayman asics doesn't work correctly and can
cause deadlocks, so turn it off for now.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Acked-by: Michal Srb <msrb@suse.com>
---
 drivers/gpu/drm/radeon/r600.c  |    3 +++
 drivers/gpu/drm/radeon/r600d.h |    1 +
 2 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index fbcd848..17ca72c 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2362,6 +2362,9 @@ void r600_semaphore_ring_emit(struct radeon_device *rdev,
 	uint64_t addr = semaphore->gpu_addr;
 	unsigned sel = emit_wait ? PACKET3_SEM_SEL_WAIT : PACKET3_SEM_SEL_SIGNAL;
 
+	if (rdev->family < CHIP_CAYMAN)
+		sel |= PACKET3_SEM_WAIT_ON_SIGNAL;
+
 	radeon_ring_write(ring, PACKET3(PACKET3_MEM_SEMAPHORE, 1));
 	radeon_ring_write(ring, addr & 0xffffffff);
 	radeon_ring_write(ring, (upper_32_bits(addr) & 0xff) | sel);
diff --git a/drivers/gpu/drm/radeon/r600d.h b/drivers/gpu/drm/radeon/r600d.h
index 3ee1fd7..9b23670 100644
--- a/drivers/gpu/drm/radeon/r600d.h
+++ b/drivers/gpu/drm/radeon/r600d.h
@@ -831,6 +831,7 @@
 #define	PACKET3_STRMOUT_BUFFER_UPDATE			0x34
 #define	PACKET3_INDIRECT_BUFFER_MP			0x38
 #define	PACKET3_MEM_SEMAPHORE				0x39
+#              define PACKET3_SEM_WAIT_ON_SIGNAL    (0x1 << 12)
 #              define PACKET3_SEM_SEL_SIGNAL	    (0x6 << 29)
 #              define PACKET3_SEM_SEL_WAIT	    (0x7 << 29)
 #define	PACKET3_MPEG_INDEX				0x3A

