Re: [PATCH v6 4/5] drm/msm: Refactor address space initialization

[Eric Anholt]

On Wed, Jun 17, 2020 at 1:16 PM Eric Anholt <eric@xxxxxxxxxx> wrote:
>
> On Thu, Apr 9, 2020 at 4:34 PM Jordan Crouse <jcrouse@xxxxxxxxxxxxxx> wrote:
> >
> > Refactor how address space initialization works. Instead of having the
> > address space function create the MMU object (and thus require separate but
> > equal functions for gpummu and iommu) use a single function and pass the
> > MMU struct in. Make the generic code cleaner by using target specific
> > functions to create the address space so a2xx can do its own thing in its
> > own space.  For all the other targets use a generic helper to initialize
> > IOMMU but leave the door open for newer targets to use customization
> > if they need it.
>
> I'm seeing regressions in dEQP-VK.memory.allocation.random.* on cheza
> after this commit.   The symptom is that large allocations fail with
> -ENOSPC from MSM_GEM_INFO(IOVA).
>
> Possibly relevant change from having stuffed some debug info in:
>
> before:
> [    3.791436] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x1000000 + 0xfeffffff
> [    3.801672] platform 506a000.gmu: Adding to iommu group 6
> [    3.807359] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x0 + 0x7fffffff
> [    3.817140] msm ae00000.mdss: bound 5000000.gpu (ops a3xx_ops)
> [    3.823212] msm_dpu ae01000.mdp: [drm:msm_ioremap] *ERROR* failed
> to get memory resource: vbif_nrt
> [    3.832429] msm_dpu ae01000.mdp: [drm:msm_ioremap] *ERROR* failed
> to get memory resource: regdma
> [    3.841478] [drm:dpu_kms_hw_init:878] dpu hardware revision:0x40000000
> [    3.848193] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x1000 + 0xffffefff
>
> after:
>
> [    3.798707] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x1000000 + 0xfffffff
> [    3.808731] platform 506a000.gmu: Adding to iommu group 6
> [    3.814440] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x0 + 0x7fffffff
> [    3.820494] hub 2-1:1.0: USB hub found
> [    3.824108] msm ae00000.mdss: bound 5000000.gpu (ops a3xx_ops)
> [    3.828554] hub 2-1:1.0: 4 ports detected
> [    3.833756] msm_dpu ae01000.mdp: [drm:msm_ioremap] *ERROR* failed
> to get memory resource: vbif_nrt
> [    3.847038] msm_dpu ae01000.mdp: [drm:msm_ioremap] *ERROR* failed
> to get memory resource: regdma
> [    3.856095] [drm:dpu_kms_hw_init:878] dpu hardware revision:0x40000000
> [    3.862840] [drm:msm_gem_address_space_create] *ERROR* msmgem
> address space create: 0x1000 + 0xfffffff
>
> 256MB for GMU address space?

Found the bug, fixes at the last 2 commits of
https://github.com/anholt/linux/tree/drm-msm-address-space

I'm going to try having another go at convincing gmail to let git
send-email through, but all the howtos in the world didn't work last
time (gsuite has different behavior from normal gmail).