From 62d91dd2851e8ae2ca552f1b090a3575a4edf759 Mon Sep 17 00:00:00 2001
From: Sam Bobroff <sbobroff@linux.ibm.com>
Date: Mon, 18 Nov 2019 10:53:53 +1100
Subject: [PATCH] drm/radeon: fix bad DMA from INTERRUPT_CNTL2
Git-commit: 62d91dd2851e8ae2ca552f1b090a3575a4edf759
Patch-mainline: v5.5-rc1
References: git-fixes
The INTERRUPT_CNTL2 register expects a valid DMA address, but is
currently set with a GPU MC address. This can cause problems on
systems that detect the resulting DMA read from an invalid address
(found on a Power8 guest).
Instead, use the DMA address of the dummy page because it will always
be safe.
Fixes: d8f60cfc9345 ("drm/radeon/kms: Add support for interrupts on r6xx/r7xx chips (v3)")
Fixes: 25a857fbe973 ("drm/radeon/kms: add support for interrupts on SI")
Fixes: a59781bbe528 ("drm/radeon: add support for interrupts on CIK (v5)")
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/radeon/cik.c | 4 ++--
drivers/gpu/drm/radeon/r600.c | 4 ++--
drivers/gpu/drm/radeon/si.c | 4 ++--
3 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index daff9a2af3be..acabeaf28732 100644
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -6965,8 +6965,8 @@ static int cik_irq_init(struct radeon_device *rdev)
}
/* setup interrupt control */
- /* XXX this should actually be a bus address, not an MC address. same on older asics */
- WREG32(INTERRUPT_CNTL2, rdev->ih.gpu_addr >> 8);
+ /* set dummy read address to dummy page address */
+ WREG32(INTERRUPT_CNTL2, rdev->dummy_page.addr >> 8);
interrupt_cntl = RREG32(INTERRUPT_CNTL);
/* IH_DUMMY_RD_OVERRIDE=0 - dummy read disabled with msi, enabled without msi
* IH_DUMMY_RD_OVERRIDE=1 - dummy read controlled by IH_DUMMY_RD_EN
diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index e937cc01910d..033bc466a862 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3696,8 +3696,8 @@ int r600_irq_init(struct radeon_device *rdev)
}
/* setup interrupt control */
- /* set dummy read address to ring address */
- WREG32(INTERRUPT_CNTL2, rdev->ih.gpu_addr >> 8);
+ /* set dummy read address to dummy page address */
+ WREG32(INTERRUPT_CNTL2, rdev->dummy_page.addr >> 8);
interrupt_cntl = RREG32(INTERRUPT_CNTL);
/* IH_DUMMY_RD_OVERRIDE=0 - dummy read disabled with msi, enabled without msi
* IH_DUMMY_RD_OVERRIDE=1 - dummy read controlled by IH_DUMMY_RD_EN
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 05894d198a79..1d8efb0eefdb 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -5997,8 +5997,8 @@ static int si_irq_init(struct radeon_device *rdev)
}
/* setup interrupt control */
- /* set dummy read address to ring address */
- WREG32(INTERRUPT_CNTL2, rdev->ih.gpu_addr >> 8);
+ /* set dummy read address to dummy page address */
+ WREG32(INTERRUPT_CNTL2, rdev->dummy_page.addr >> 8);
interrupt_cntl = RREG32(INTERRUPT_CNTL);
/* IH_DUMMY_RD_OVERRIDE=0 - dummy read disabled with msi, enabled without msi
* IH_DUMMY_RD_OVERRIDE=1 - dummy read controlled by IH_DUMMY_RD_EN
--
2.16.4