Re: [PATCH v3 (alternative) 1/3] drm/exynos: fimd: ensure proper hw state in fimd_clear_channel()

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hello,

On 2015-06-12 14:10, Inki Dae wrote:
> On 2015년 06월 12일 18:07, Marek Szyprowski wrote:
>> One should not do any assumptions on the stare of the fimd hardware
>> during driver initialization, so to properly reset fimd before enabling
>> IOMMU, one should ensure that all power domains and clocks are really
>> enabled. This patch adds pm_runtime and clocks management in the
>> fimd_clear_channel() function to ensure that any access to fimd
>> registers will be performed with clocks and power domains enabled.
>>
>> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
>> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
>> ---
>> Changelog:
>> v3 (alternative):
>> - araranged code by moving fimd_{enable,disable}_vblank functions before
>>    fimd_clear_channel to avoid forward declaration usage
> Marek,
>
> For the iommu and atomic feature test, I merged below patches in
> addition and tested them.
>
> [PATCH v2 1/3] drm/exynos: remove to call mixer_wait_for_vblank
> [PATCH v2 2/3] drm/exynos: remove chained calls to enable
> [PATCH v2 3/3] drm/exynos: initialize VIDCON0 when fimd is disabled
>
>
> However, I see below one warning log,
>
> [    1.227115] [drm] Initialized drm 1.1.0 20060810
> [    1.235852] exynos-drm exynos-drm: bound exynos-drm-vidi (ops
> vidi_component_ops)
> [    1.253548] ------------[ cut here ]------------
> [    1.256700] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/drm_irq.c:1718
> drm_handle_vblank+0x2a0/0x308()
> [    1.265800] Modules linked in:
> [    1.268844] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
> 4.1.0-rc4-00574-gf8eb363-dirty #1412
> [    1.277085] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
> [    1.283184] [<c0015464>] (unwind_backtrace) from [<c00123c0>]
> (show_stack+0x10/0x14)
> [    1.288540] exynos-drm exynos-drm: bound 11c00000.fimd (ops
> fimd_component_ops)
> [    1.288883] exynos-drm exynos-drm: bound 11c80000.dsi (ops
> exynos_dsi_component_ops)
> [    1.288888] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
> [    1.288891] [drm] No driver support for vblank timestamp query.
> [    1.288932] [drm] Initialized exynos 1.0.0 20110530 on minor 0
> [    1.324248] [<c00123c0>] (show_stack) from [<c0528f74>]
> (dump_stack+0x84/0xc4)
> [    1.331437] [<c0528f74>] (dump_stack) from [<c00246ac>]
> (warn_slowpath_common+0x80/0xb0)
> [    1.339504] [<c00246ac>] (warn_slowpath_common) from [<c0024778>]
> (warn_slowpath_null+0x1c/0x24)
> [    1.348270] [<c0024778>] (warn_slowpath_null) from [<c029c898>]
> (drm_handle_vblank+0x2a0/0x308)
> [    1.356965] [<c029c898>] (drm_handle_vblank) from [<c02b8c80>]
> (fimd_irq_handler+0x78/0xd0)
> [    1.365292] [<c02b8c80>] (fimd_irq_handler) from [<c00608f8>]
> (handle_irq_event_percpu+0x78/0x134)
> [    1.374231] [<c00608f8>] (handle_irq_event_percpu) from [<c00609f0>]
> (handle_irq_event+0x3c/0x5c)
> [    1.374244] [<c00609f0>] (handle_irq_event) from [<c0063698>]
> (handle_level_irq+0xc4/0x13c)
> [    1.374256] [<c0063698>] (handle_level_irq) from [<c005ff7c>]
> (generic_handle_irq+0x2c/0x3c)
> [    1.374269] [<c005ff7c>] (generic_handle_irq) from [<c02214ec>]
> (combiner_handle_cascade_irq+0x94/0x100)
> [    1.374281] [<c02214ec>] (combiner_handle_cascade_irq) from
> [<c005ff7c>] (generic_handle_irq+0x2c/0x3c)
> [    1.374290] [<c005ff7c>] (generic_handle_irq) from [<c0060248>]
> (__handle_domain_irq+0x7c/0xec)
> [    1.374300] [<c0060248>] (__handle_domain_irq) from [<c0009434>]
> (gic_handle_irq+0x30/0x68)
>
>
> And below one page fault error when modetest is terminated,
>
> # modetest -M exynos -v -s 31@29:720x1280
> setting mode 720x1280-60Hz@XR24 on connectors 31, crtc 29
> freq: 59.99Hz
>
> [   34.831025] PAGE FAULT occurred at 0x20400000 by 11e20000.sysmmu(Page
> table base: 0x6e324000)
> [   34.838072]  Lv1 entry: 0x6e92dc01
> [   34.841489] ------------[ cut here ]------------
> [   34.846058] kernel BUG at drivers/iommu/exynos-iommu.c:364!
> [   34.851614] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
> [   34.857428] Modules linked in:
> [   34.860472] CPU: 0 PID: 6 Comm: kworker/u8:0 Tainted: G        W
>    4.1.0-rc4-00574-gf8eb363-dirty #1412
> [   34.870188] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
> [   34.876273] Workqueue: events_unbound async_run_entry_fn
> [   34.881560] task: ee879540 ti: ee8a2000 task.ti: ee8a2000
> [   34.886946] PC is at exynos_sysmmu_irq+0x184/0x208
> [   34.891716] LR is at exynos_sysmmu_irq+0xd4/0x208
> [   34.896404] pc : [<c02880d0>]    lr : [<c0288020>]    psr: 60000193
> [   34.896404] sp : ee8a3c00  ip : 00000000  fp : eeacbc10
> [   34.907860] r10: c07c27ef  r9 : 00000204  r8 : 20400000
> [   34.913068] r7 : ee324000  r6 : ee9b3428  r5 : ee9b3410  r4 : 00000000
> [   34.919577] r3 : 6e92dc01  r2 : 6e92dc01  r1 : eea55810  r0 : eeb0a000
> [   34.926089] Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM
> Segment kernel
> [   34.933466] Control: 10c5387d  Table: 6dd2c04a  DAC: 00000015
> [   34.939195] Process kworker/u8:0 (pid: 6, stack limit = 0xee8a2210)
> [   34.945444] Stack: (0xee8a3c00 to 0xee8a4000)
> [   34.949788] 3c00: ee8a3c0c c0049df8 00000000 6e324000 0003d4f3
> ee9b13c0 ee84ad20 00000000
> [   34.957947] 3c20: 00000000 00000026 ee84acc0 c00608f8 60000093
> eef84580 ee84acc0 ee84ad20
> [   34.966106] 3c40: ee9b13c0 00000015 ee804450 ee8a3cd8 ee808000
> c00609f0 ee84acc0 ee84ad20
> [   34.974265] 3c60: ee807000 c0063698 00000026 c079d6f8 ee807000
> c005ff7c 0000000a c02214ec
> [   34.982424] 3c80: 00000015 00000000 00000015 00000000 00000001
> c005ff7c c0789aac c0060248
> [   34.990583] 3ca0: f002000c 00000015 c078e7ac ee8a3cd8 f0020000
> ee8a2000 00000001 c0009434
> [   34.998742] 3cc0: c052e8fc 60000013 ffffffff ee8a3d0c 00000004
> c0012ec0 eeacbd18 ee879540
> [   35.006901] 3ce0: 00000000 00000271 eeacbd18 00000000 eea55010
> c078e100 00000004 ee8a2000
> [   35.015061] 3d00: 00000001 eeacbc10 eeacbd88 ee8a3d20 c052e8f8
> c052e8fc 60000013 ffffffff
> [   35.023220] 3d20: eeacbd18 c02dab48 20000113 00000003 60000013
> eeacbd18 00000004 eeacbc60
> [   35.031379] 3d40: ffff30d5 eeacbca8 eeacbd18 00000004 60000013
> ffff30d5 c0802fe8 c02db05c
> [   35.039538] 3d60: eeacbc60 00000002 c078e100 eeacbc60 ffff30d5
> c03b0f2c c078bb40 ee8a3e28
> [   35.047697] 3d80: 00000001 ee8a3db8 eeacbc70 00000002 eeacbc70
> ee8a3db8 eeacbca8 c052e880
> [   35.055857] 3da0: eeacbc70 c052d818 00000000 00000009 00000000
> c002791c ee8a3db8 11111111
> [   35.064016] 3dc0: 11111111 ee8a3dc4 11111111 eeacbc60 00000002
> c078e100 ee8a3e28 ffff30d5
> [   35.072175] 3de0: c0802fe8 00000001 ee80b400 c03ac4cc 00000000
> eeacbc60 ee8a3e28 00000002
> [   35.080334] 3e00: eea47ac0 00000000 ee849d00 c03ac69c 00000000
> 00000001 00000001 eea47ac0
> [   35.088493] 3e20: eea47ac0 c02e9f10 00000009 60000001 eea47ac0
> 00010009 00000001 eea47ac0
> [   35.096653] 3e40: ee29149c 00000000 ee00c200 c02e5bdc 00000001
> c004425c ee00c200 00000047
> [   35.104812] 3e60: ee00c200 ee00c200 ee8a3eb4 ee8a3eb4 00000000
> c02e5c5c ee00c200 ee00c200
> [   35.112971] 3e80: 00000047 c02e564c ee00c200 00000047 ee8a3eb4
> ee80da00 00000000 c02e5704
> [   35.121130] 3ea0: eeafd800 c07c5020 eeafd84c c025383c ee849d00
> c052d110 eeafd800 c0252a48
> [   35.129289] 3ec0: ee914724 c07c5020 edcc9c40 c0252f58 edcc9c50
> c003ed48 eef84580 eea2f700
> [   35.137448] 3ee0: ee849d00 edcc9c50 ee80b400 c0037944 ee8a2000
> ee80b400 00000001 ee80b400
> [   35.145608] 3f00: ee849d18 ee80b420 ee8a2000 00000088 c07c27bc
> ee849d00 ee80b400 c0037ba0
> [   35.153767] 3f20: c078e100 ee80b570 ee849d00 00000000 ee84b540
> ee849d00 c0037b54 00000000
> [   35.161926] 3f40: 00000000 00000000 00000000 c003c8b8 ffffffff
> 00000000 ffffffff ee849d00
> [   35.170085] 3f60: 00000000 00000000 dead4ead ffffffff ffffffff
> ee8a3f74 ee8a3f74 00000000
> [   35.178245] 3f80: 00000000 dead4ead ffffffff ffffffff ee8a3f90
> ee8a3f90 ee8a3fac ee84b540
> [   35.186403] 3fa0: c003c7dc 00000000 00000000 c000f5a0 00000000
> 00000000 00000000 00000000
> [   35.194562] 3fc0: 00000000 00000000 00000000 00000000 00000000
> 00000000 00000000 00000000
> [   35.202722] 3fe0: 00000000 00000000 00000000 00000000 00000013
> 00000000 ffffffff ffffffff
> [   35.210894] [<c02880d0>] (exynos_sysmmu_irq) from [<c00608f8>]
> (handle_irq_event_percpu+0x78/0x134)
> [   35.219914] [<c00608f8>] (handle_irq_event_percpu) from [<c00609f0>]
> (handle_irq_event+0x3c/0x5c)
> [   35.228768] [<c00609f0>] (handle_irq_event) from [<c0063698>]
> (handle_level_irq+0xc4/0x13c)
> [   35.237101] [<c0063698>] (handle_level_irq) from [<c005ff7c>]
> (generic_handle_irq+0x2c/0x3c)
> [   35.245521] [<c005ff7c>] (generic_handle_irq) from [<c02214ec>]
> (combiner_handle_cascade_irq+0x94/0x100)
> [   35.254980] [<c02214ec>] (combiner_handle_cascade_irq) from
> [<c005ff7c>] (generic_handle_irq+0x2c/0x3c)
> [   35.264353] [<c005ff7c>] (generic_handle_irq) from [<c0060248>]
> (__handle_domain_irq+0x7c/0xec)
> [   35.273034] [<c0060248>] (__handle_domain_irq) from [<c0009434>]
> (gic_handle_irq+0x30/0x68)
> [   35.281366] [<c0009434>] (gic_handle_irq) from [<c0012ec0>]
> (__irq_svc+0x40/0x74)
>
> Could you check the iommu with atomic feature? I tested these features
> on trats2 board, and enabled one more crtc drivers - HDMI, VIDI, and FIMD.

I've tested it on Trats2 with FIMD and Odroid U3 with HDMI and I didn't 
manage to
trigger page fault issue.

I've pushed the branch I've used for testing here:
https://git.linaro.org/people/marek.szyprowski/linux-srpol.git 
v4.1-exynos-drm-iommu

> To other Exynos guys,
> could you guys check the same issues also? If you give some helps to us,
> we'd be glad.
>
> Thanks,
> Inki Dae

> > (...)

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland