Re: [PATCH 1/2] drm/amdgpu: add the IP information of the soc

[Alex Deucher]

On Thu, Mar 14, 2024 at 1:44 AM Khatri, Sunil <sukhatri@xxxxxxx> wrote:
>
>
> On 3/14/2024 1:58 AM, Alex Deucher wrote:
> > On Tue, Mar 12, 2024 at 8:41 AM Sunil Khatri <sunil.khatri@xxxxxxx> wrote:
> >> Add all the IP's information on a SOC to the
> >> devcoredump.
> >>
> >> Signed-off-by: Sunil Khatri <sunil.khatri@xxxxxxx>
> >> ---
> >>   drivers/gpu/drm/amd/amdgpu/amdgpu_reset.c | 19 +++++++++++++++++++
> >>   1 file changed, 19 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_reset.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_reset.c
> >> index a0dbccad2f53..611fdb90a1fc 100644
> >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_reset.c
> >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_reset.c
> >> @@ -196,6 +196,25 @@ amdgpu_devcoredump_read(char *buffer, loff_t offset, size_t count,
> >>                             coredump->reset_task_info.process_name,
> >>                             coredump->reset_task_info.pid);
> >>
> >> +       /* GPU IP's information of the SOC */
> >> +       if (coredump->adev) {
> >> +               drm_printf(&p, "\nIP Information\n");
> >> +               drm_printf(&p, "SOC Family: %d\n", coredump->adev->family);
> >> +               drm_printf(&p, "SOC Revision id: %d\n", coredump->adev->rev_id);
> >> +
> >> +               for (int i = 0; i < coredump->adev->num_ip_blocks; i++) {
> >> +                       struct amdgpu_ip_block *ip =
> >> +                               &coredump->adev->ip_blocks[i];
> >> +                       drm_printf(&p, "IP type: %d IP name: %s\n",
> >> +                                  ip->version->type,
> >> +                                  ip->version->funcs->name);
> >> +                       drm_printf(&p, "IP version: (%d,%d,%d)\n\n",
> >> +                                  ip->version->major,
> >> +                                  ip->version->minor,
> >> +                                  ip->version->rev);
> >> +               }
> >> +       }
> > I think the IP discovery table would be more useful.  Either walk the
> > adev->ip_versions structure, or just include the IP discovery binary.
>
> I did explore the adev->ip_versions and if i just go through the array
> it doesn't give any useful information directly.
> There are no ways to find directly from adev->ip_versions below things
> until i also reparse the discovery binary again like done the discovery
> amdgpu_discovery_reg_base_init and walk through the headers of various
> ips using discovery binary.
> a. Which IP is available on soc or not.
> b. How many instances are there
> Also i again have to change back to major, minor and rev convention for
> this information to be useful. I am exploring it more if i find some
> other information i will update.
>
> adev->ip_block[] is derived from ip discovery only for each block which
> is there on the SOC, so we are not reading information which isnt
> applicable for the soc. We have name , type and version no of the IPs
> available on the soc. If you want i could add no of instances of each IP
> too if you think that's useful information here. Could you share what
> information is missing in this approach so i can include that.

I was hoping to get the actual IP versions for the IPs from IP
discovery rather than the versions from the ip_block array.  The
latter are common so you can end up with the same version used across
a wide variety of chips (e.g., all gfx10.x based chips use the same
gfx 10 IP code even if the actual IP version is different for most of
the chips).

>
> For dumping the IP discovery binary, i dont understand how that
> information would be useful directly and needs to be decoded like we are
> doing in discovery init. Please correct me if my understanding is wrong
> here.

It's probably not a high priority, I was just thinking it might be
useful to have in case there ended up being some problem related to
the IP discovery table on some boards.  E.g., we'd know that all
boards with a certain harvest config seem to align with a reported
problem.  Similar for vbios.  It's more for telemetry.  E.g., all the
boards reporting some problem have a particular powerplay config or
whatever.

Alex


> > Alex
> >
> >> +
> >>          if (coredump->ring) {
> >>                  drm_printf(&p, "\nRing timed out details\n");
> >>                  drm_printf(&p, "IP Type: %d Ring Name: %s\n",
> >> --
> >> 2.34.1
> >>