Re: [PATCH v4 0/8] Allwinner H6 Mali GPU support

Robin Murphy
2019-05-16T11:19:11Z

On 16/05/2019 00:22, Rob Herring wrote:
> On Wed, May 15, 2019 at 5:06 PM Clément Péron <peron.clem@gmail.com> wrote:
>>
>> Hi Robin,
>>
>> On Tue, 14 May 2019 at 23:57, Robin Murphy <robin.murphy@arm.com> wrote:
>>>
>>> On 2019-05-14 10:22 pm, Clément Péron wrote:
>>>> Hi,
>>>>
>>>> On Tue, 14 May 2019 at 17:17, Clément Péron <peron.clem@gmail.com> wrote:
>>>>>
>>>>> Hi,
>>>>>
>>>>> On Tue, 14 May 2019 at 12:29, Neil Armstrong <narmstrong@baylibre.com> wrote:
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> On 13/05/2019 17:14, Daniel Vetter wrote:
>>>>>>> On Sun, May 12, 2019 at 07:46:00PM +0200, peron.clem@gmail.com wrote:
>>>>>>>> From: Clément Péron <peron.clem@gmail.com>
>>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> The Allwinner H6 has a Mali-T720 MP2. The drivers are
>>>>>>>> out-of-tree so this series only introduce the dt-bindings.
>>>>>>>
>>>>>>> We do have an in-tree midgard driver now (since 5.2). Does this stuff work
>>>>>>> together with your dt changes here?
>>>>>>
>>>>>> No, but it should be easy to add.
>>>>> I will give it a try and let you know.
>>>> Added the bus_clock and a ramp delay to the gpu_vdd but the driver
>>>> fail at probe.
>>>>
>>>> [ 3.052919] panfrost 1800000.gpu: clock rate = 432000000
>>>> [ 3.058278] panfrost 1800000.gpu: bus_clock rate = 100000000
>>>> [ 3.179772] panfrost 1800000.gpu: mali-t720 id 0x720 major 0x1
>>>> minor 0x1 status 0x0
>>>> [ 3.187432] panfrost 1800000.gpu: features: 00000000,10309e40,
>>>> issues: 00000000,21054400
>>>> [ 3.195531] panfrost 1800000.gpu: Features: L2:0x07110206
>>>> Shader:0x00000000 Tiler:0x00000809 Mem:0x1 MMU:0x00002821 AS:0xf
>>>> JS:0x7
>>>> [ 3.207178] panfrost 1800000.gpu: shader_present=0x3 l2_present=0x1
>>>> [ 3.238257] panfrost 1800000.gpu: Fatal error during GPU init
>>>> [ 3.244165] panfrost: probe of 1800000.gpu failed with error -12
>>>>
>>>> The ENOMEM is coming from "panfrost_mmu_init"
>>>> alloc_io_pgtable_ops(ARM_MALI_LPAE, &pfdev->mmu->pgtbl_cfg,
>>>> pfdev);
>>>>
>>>> Which is due to a check in the pgtable alloc "cfg->ias != 48"
>>>> arm-lpae io-pgtable: arm_mali_lpae_alloc_pgtable cfg->ias 33 cfg->oas 40
>>>>
>>>> DRI stack is totally new for me, could you give me a little clue about
>>>> this issue ?
>>>
>>> Heh, this is probably the one bit which doesn't really count as "DRI stack".
>>>
>>> That's merely a somewhat-conservative sanity check - I'm pretty sure it
>>> *should* be fine to change the test to "cfg->ias > 48" (io-pgtable
>>> itself ought to cope). You'll just get to be the first to actually test
>>> a non-48-bit configuration here :)
>>
>> Thanks a lot, the probe seems fine now :)
>>
>> I try to run glmark2 :
>> # glmark2-es2-drm
>> =======================================================
>> glmark2 2017.07
>> =======================================================
>> OpenGL Information
>> GL_VENDOR: panfrost
>> GL_RENDERER: panfrost
>> GL_VERSION: OpenGL ES 2.0 Mesa 19.1.0-rc2
>> =======================================================
>> [build] use-vbo=false:
>>
>> But it seems that H6 is not so easy to add :(.
>>
>> [ 345.204813] panfrost 1800000.gpu: mmu irq status=1
>> [ 345.209617] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
>> 0x0000000002400400
>> [ 345.209617] Reason: TODO
>> [ 345.209617] raw fault status: 0x800002C1
>> [ 345.209617] decoded fault status: SLAVE FAULT
>> [ 345.209617] exception type 0xC1: TRANSLATION_FAULT_LEVEL1
>> [ 345.209617] access type 0x2: READ
>> [ 345.209617] source id 0x8000
>> [ 345.729957] panfrost 1800000.gpu: gpu sched timeout, js=0,
>> status=0x8, head=0x2400400, tail=0x2400400, sched_job=000000009e204de9
>> [ 346.055876] panfrost 1800000.gpu: mmu irq status=1
>> [ 346.060680] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
>> 0x0000000002C00A00
>> [ 346.060680] Reason: TODO
>> [ 346.060680] raw fault status: 0x810002C1
>> [ 346.060680] decoded fault status: SLAVE FAULT
>> [ 346.060680] exception type 0xC1: TRANSLATION_FAULT_LEVEL1
>> [ 346.060680] access type 0x2: READ
>> [ 346.060680] source id 0x8100
>> [ 346.561955] panfrost 1800000.gpu: gpu sched timeout, js=1,
>> status=0x8, head=0x2c00a00, tail=0x2c00a00, sched_job=00000000b55a9a85
>> [ 346.573913] panfrost 1800000.gpu: mmu irq status=1
>> [ 346.578707] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
>> 0x0000000002C00B80
>> [ 346.578707] Reason: TODO
>> [ 346.578707] raw fault status: 0x800002C1
>> [ 346.578707] decoded fault status: SLAVE FAULT
>> [ 346.578707] exception type 0xC1: TRANSLATION_FAULT_LEVEL1
>> [ 346.578707] access type 0x2: READ
>> [ 346.578707] source id 0x8000
>> [ 347.073947] panfrost 1800000.gpu: gpu sched timeout, js=0,
>> status=0x8, head=0x2c00b80, tail=0x2c00b80, sched_job=00000000cf6af8e8
>> [ 347.104125] panfrost 1800000.gpu: mmu irq status=1
>> [ 347.108930] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
>> 0x0000000002800900
>> [ 347.108930] Reason: TODO
>> [ 347.108930] raw fault status: 0x810002C1
>> [ 347.108930] decoded faultn thi status: SLAVE FAULT
>> [ 347.108930] exception type 0xC1: TRANSLATION_FAULT_LEVEL1
>> [ 347.108930] access type 0x2: READ
>> [ 347.108930] source id 0x8100
>> [ 347.617950] panfrost 1800000.gpu: gpu sched timeout, js=1,
>> status=0x8, head=0x2800900, tail=0x2800900, sched_job=000000009325fdb7
>> [ 347.629902] panfrost 1800000.gpu: mmu irq status=1
>> [ 347.634696] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
>> 0x0000000002800A80
>
> Is this 32 or 64 bit userspace? I think 64-bit does not work with
> T7xx. You might need this[1].

[ Oooh... that makes T620 actually do stuff without falling over
dereferencing VA 0 somewhere halfway through the job chain :D

I shall continue to play... ]

> You may also be the first to try T720,
> so it could be something else.

I was expecting to see a similar behaviour to my T620 (which I now
assume was down to 64-bit job descriptors sort-of-but-not-quite working)
but this does look a bit more fundamental - the fact that it's a level 1
fault with VA == head == tail suggests to me that the MMU can't see the
page tables at all to translate anything. I really hope that the H6 GPU
integration doesn't suffer from the same DMA offset as the Allwinner
display pipeline stuff, because that would be a real pain to support in
io-pgtable.

Robin.