Re: [PATCH 00/12] RFC: drm/amdgpu/sdma: Refactor SDMA v4 and older functions to be per-instance

["Timur Kristóf" <timur.kristof@gmail.com>]

On 2026. szeptember 16., szerda 22:23:42 közép-európai nyári idő Alex Deucher 
wrote:
> On Tue, Sep 15, 2026 at 1:23 PM Timur Kristóf <timur.kristof@gmail.com> 
wrote:
> > On Friday, September 11, 2026 9:00:07 PM Central European Summer Time Alex
> > 
> > Deucher wrote:
> > > On Mon, Sep 7, 2026 at 4:40 PM Timur Kristóf <timur.kristof@gmail.com>
> > 
> > wrote:
> > > > This series applies on top of my previous series:
> > > > "Improve existing SDMA queue resets" (currently under review)
> > > > 
> > > > Prepare the code for implementing recovery for
> > > > SDMA v4 and all older SDMA (and SI DMA) versions.
> > > > Reorganize the SDMA 4.0 code so that the functions that are
> > > > responsible for managing the SDMA engines take an instance ID
> > > > as an argument.
> > > > 
> > > > This makes it possible to manage the SDMA instances
> > > > independently of each other, which will enable us to
> > > > also use these functions to implement resetting and
> > > > recovering them independently. (The actual recovery
> > > > implementation will be in a follow-up patch series
> > > > which I will submit after this one is accepted.)
> > > 
> > > This series looks fine to me, although I think I would prefer to apply
> > > it along with the relevant soft reset changes to avoid churning the
> > > code until each family is ready.  E.g., apply the cik_sdma refactor
> > > along with the CIK soft reset support, etc.  Unless you have something
> > > else in mind.
> > 
> > Thank you Alex.
> > 
> > My plan is the following:
> > 
> > 1. I would like to first refactor the functions for every SDMA IP block
> > version to be per-instance.
> > 2. Then, I'd like to improve the soft reset code, more specifically the
> > multi- ring reset helpers and amdgpu_device_ip_soft_reset() to make them
> > aware of IP block instances and change SDMA v4.4.2, v5.0 and v5.2 over to
> > use that code. 3. With all of that out of the way, it will be pretty easy
> > to hook up the same soft reset mechanism for SI, CIK, VI as well.
> > 4. At that point, we should also consider if we want soft reset for SDMA
> > v6
> > and v7. Technically these versions support proper queue reset through the
> > MES, but in practice I've seen the MES fail so often that I wouldn't
> > consider it stable.
> > 
> > This RFC is basically a prototype for step (1) and only takes care of SDMA
> > v4 and older just to show how I imagine doing the refactor. If you like
> > this direction, I would like to do the same for all IP versions before
> > moving forward with soft reset changes and other refactors. I prefer to
> > do this first for all IP versions because I think it's important to have
> > consistency within the code base regarding how the SDMA is programmed.
> > 
> > What do you think, would that be OK for you?
> 
> Do you have a PoC working on at least one generation based on the code
> restructure?  I guess I'd rather not restructure everything until you
> know the end result actually works for what you are trying to do.

(Sorry for the late reply.)

Okay, that sounds reasonable to me. I will get back to you once I got it fully 
working on multiple HW generations.

Thanks & best regards,
Timur