On 2023-03-17 16:04, Sider, Graham wrote:
[AMD Official Use Only - General]
-----Original Message-----
From: Russell, Kent <Kent.Russell@xxxxxxx>
Sent: Friday, March 17, 2023 3:58 PM
To: Mahfooz, Hamza <Hamza.Mahfooz@xxxxxxx>; Sider, Graham
<Graham.Sider@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Kuehling, Felix <Felix.Kuehling@xxxxxxx>
Subject: RE: [PATCH] drm/amdgpu: add print for iommu translation mode
[AMD Official Use Only - General]
-----Original Message-----
From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of
Hamza Mahfooz
Sent: Friday, March 17, 2023 3:58 PM
To: Sider, Graham <Graham.Sider@xxxxxxx>;
amd-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Kuehling, Felix <Felix.Kuehling@xxxxxxx>
Subject: Re: [PATCH] drm/amdgpu: add print for iommu translation mode
On 3/17/23 15:47, Graham Sider wrote:
Add log to display whether RAM is direct vs DMA mapped.
Signed-off-by: Graham Sider <Graham.Sider@xxxxxxx>
If this information is only useful for debugging purposes, please use
drm_dbg() instead of pr_info().
It's useful for more than just debug I would say. Just a quick way to grep whether IOMMU is off/pt vs device isolation mode.
I agree. The kernel log otherwise tells you the default IOMMU domain,
but it may not match the domain actually used for the GPU. Without this
message there is no easy way to tell from a kernel log. This will help
with triaging issues from logs provided by external and internal users.
Graham
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 8bba5e6872a1..8797a9523244 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3528,8 +3528,12 @@ static void
amdgpu_device_check_iommu_direct_map(struct amdgpu_device *adev)
struct iommu_domain *domain;
domain = iommu_get_domain_for_dev(adev->dev);
- if (!domain || domain->type == IOMMU_DOMAIN_IDENTITY)
+ if (!domain || domain->type == IOMMU_DOMAIN_IDENTITY) {
+ pr_info("RAM is direct mapped to GPU (not traslated by
Use dev_info. That way you can tell which GPU the message applies to in
a multi-GPU system.
Regards,
Felix
traslated -> translated
Thanks, my keyboard keeps skipping the on the 'n' key lately :( time for a clean.
Graham
Kent
IOMMU)\n");
adev->ram_is_direct_mapped = true;
+ } else {
+ pr_info("RAM is DMA mapped to GPU (translated by
IOMMU)\n");
+ }
}
static const struct attribute *amdgpu_dev_attributes[] = {
--
Hamza
