On 12/1/2021 4:08 PM, Yu, Lang wrote:
[AMD Official Use Only]
-----Original Message-----
From: Lazar, Lijo <Lijo.Lazar@xxxxxxx>
Sent: Wednesday, December 1, 2021 5:47 PM
To: Yu, Lang <Lang.Yu@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Huang, Ray
<Ray.Huang@xxxxxxx>; Koenig, Christian <Christian.Koenig@xxxxxxx>
Subject: Re: [PATCH] drm/amdgpu: add support to SMU debug option
On 12/1/2021 2:54 PM, Lang Yu wrote:
To maintain system error state when SMU errors occurred, which will
aid in debugging SMU firmware issues, add SMU debug option support.
It can be enabled or disabled via amdgpu_smu_debug debugfs file. When
enabled, it makes SMU errors fatal.
It is disabled by default.
== Command Guide ==
1, enable SMU debug option
# echo 1 > /sys/kernel/debug/dri/0/amdgpu_smu_debug
2, disable SMU debug option
# echo 0 > /sys/kernel/debug/dri/0/amdgpu_smu_debug
v3:
- Use debugfs_create_bool().(Christian)
- Put variable into smu_context struct.
- Don't resend command when timeout.
v2:
- Resend command when timeout.(Lijo)
- Use debugfs file instead of module parameter.
Signed-off-by: Lang Yu <lang.yu@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 3 +++
drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h | 5 +++++
drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c | 2 ++
drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c | 8 +++++++-
4 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index 164d6a9e9fbb..86cd888c7822 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -1618,6 +1618,9 @@ int amdgpu_debugfs_init(struct amdgpu_device
*adev)
if (!debugfs_initialized())
return 0;
+ debugfs_create_bool("amdgpu_smu_debug", 0600, root,
+ &adev->smu.smu_debug_mode);
+
ent = debugfs_create_file("amdgpu_preempt_ib", 0600, root, adev,
&fops_ib_preempt);
if (IS_ERR(ent)) {
diff --git a/drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h
b/drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h
index f738f7dc20c9..50dbf5594a9d 100644
--- a/drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h
+++ b/drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h
@@ -569,6 +569,11 @@ struct smu_context
struct smu_user_dpm_profile user_dpm_profile;
struct stb_context stb_context;
+ /*
+ * When enabled, it makes SMU errors fatal.
+ * (0 = disabled (default), 1 = enabled)
+ */
+ bool smu_debug_mode;
};
struct i2c_adapter;
diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
index 6e781cee8bb6..d3797a2d6451 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c
@@ -1919,6 +1919,8 @@ static int aldebaran_mode2_reset(struct
smu_context *smu)
out:
mutex_unlock(&smu->message_lock);
+ BUG_ON(unlikely(smu->smu_debug_mode) && ret);
+
This hunk can be skipped while submitting. If this fails, GPU reset will fail and
amdgpu won't continue.
Ok, we don't handle such cases.
return ret;
}
diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
b/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
index 048ca1673863..9be005eb4241 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c
@@ -349,15 +349,21 @@ int smu_cmn_send_smc_msg_with_param(struct
smu_context *smu,
__smu_cmn_reg_print_error(smu, reg, index, param, msg);
goto Out;
}
+
__smu_cmn_send_msg(smu, (uint16_t) index, param);
reg = __smu_cmn_poll_stat(smu);
res = __smu_cmn_reg2errno(smu, reg);
- if (res != 0)
+ if (res != 0) {
__smu_cmn_reg_print_error(smu, reg, index, param, msg);
+ goto Out;
Next step is reading smu parameter register which is harmless as reading
response register and it's not clear on read. This goto also may be skipped.
I just think that does some extra work. We don’t want to read response register.
This goto makes error handling more clear.
This change affects non-debug mode also. If things are normal, error
handling is supposed to be done by the caller based on the FW response
and/or return parameter value, if there is any. smu_debug_mode shouldn't
change that.
Thanks,
Lijo
Regards,
Lang
Thanks,
Lijo
+ }
if (read_arg)
smu_cmn_read_arg(smu, read_arg);
Out:
mutex_unlock(&smu->message_lock);
+
+ BUG_ON(unlikely(smu->smu_debug_mode) && res);
+
return res;
}
