[PATCH 1/2] drm: exynos: dsi: Convert to bridge driver

Jagan Teki jagan at amarulasolutions.com
Mon Jan 10 11:17:37 UTC 2022


Hi Robert,

On Mon, Nov 22, 2021 at 9:34 PM Marek Szyprowski
<m.szyprowski at samsung.com> wrote:
>
> On 22.11.2021 16:07, Marek Szyprowski wrote:
> > On 22.11.2021 15:55, Jagan Teki wrote:
> >> On Mon, Nov 22, 2021 at 7:59 PM Jagan Teki
> >> <jagan at amarulasolutions.com> wrote:
> >>> On Mon, Nov 22, 2021 at 7:51 PM Jagan Teki
> >>> <jagan at amarulasolutions.com> wrote:
> >>>> On Mon, Nov 22, 2021 at 7:45 PM Marek Szyprowski
> >>>> <m.szyprowski at samsung.com> wrote:
> >>>>> On 22.11.2021 08:06, Jagan Teki wrote:
> >>>>>> Some display panels would come up with a non-DSI output, those
> >>>>>> can have an option to connect the DSI host by means of interface
> >>>>>> bridge converter.
> >>>>>>
> >>>>>> This DSI to non-DSI interface bridge converter would requires
> >>>>>> DSI Host to handle drm bridge functionalities in order to DSI
> >>>>>> Host to Interface bridge.
> >>>>>>
> >>>>>> This patch convert the existing to a drm bridge driver with a
> >>>>>> built-in encoder support for compatibility with existing
> >>>>>> component drivers.
> >>>>>>
> >>>>>> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
> >>>>>> ---
> >>>>>> Note:
> >>>>>> Hi Marek Szyprowski,
> >>>>>>
> >>>>>> Please test this on Panel and Bridge hardware.
> >>>>> I don't have good news, t crashes:
> >>>>>
> >>>>> [drm] Exynos DRM: using 13800000.decon device for DMA mapping
> >>>>> operations
> >>>>> exynos-drm exynos-drm: bound 13800000.decon (ops decon_component_ops)
> >>>>> exynos-drm exynos-drm: bound 13880000.decon (ops decon_component_ops)
> >>>>> exynos-drm exynos-drm: bound 13930000.mic (ops
> >>>>> exynos_mic_component_ops)
> >>>>> [drm:drm_bridge_attach] *ERROR* failed to attach bridge
> >>>>> /soc at 0/dsi at 13900000 to encoder TMDS-67: -22
> >>>>> exynos-drm exynos-drm: failed to bind 13900000.dsi (ops
> >>>>> exynos_dsi_component_ops): -22
> >>>>> Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
> >>>>> Modules linked in:
> >>>>> CPU: 2 PID: 74 Comm: kworker/u16:1 Not tainted 5.16.0-rc1+ #4141
> >>>>> Hardware name: Samsung TM2E board (DT)
> >>>>> Workqueue: events_unbound deferred_probe_work_func
> >>>>> pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >>>>> pc : decon_atomic_disable+0x58/0xd4
> >>>>> lr : decon_atomic_disable+0x28/0xd4
> >>>>> sp : ffff80001390b940
> >>>>> x29: ffff80001390b940 x28: ffff80001259a000 x27: ffff000027f39e80
> >>>>> input: stmfts as
> >>>>> /devices/platform/soc at 0/14ed0000.hsi2c/i2c-3/3-0049/input/input0
> >>>>> x26: 00000000ffffffea x25: ffff000025a40280 x24: 0000000000000001
> >>>>> x23: ffff800011b55f98 x22: ffff0000315dc000 x21: ffff00002695d100
> >>>>> x20: ffff000027e7a080 x19: ffff0000315e6000 x18: 0000000000000000
> >>>>> x17: 645f736f6e797865 x16: 2073706f28206973 x15: 0000000000028ee0
> >>>>> x14: 0000000000000028 x13: 0000000000000001 x12: 0000000000000040
> >>>>> x11: ffff000023c18920 x10: ffff000023c18922 x9 : ffff8000126352f0
> >>>>> x8 : ffff000023c00270 x7 : 0000000000000000 x6 : ffff000023c00268
> >>>>> x5 : ffff000027e7a3a0 x4 : 0000000000000001 x3 : ffff000027e7a080
> >>>>> x2 : 0000000000000024 x1 : ffff800013bc8024 x0 : ffff0000246117c0
> >>>>> Call trace:
> >>>>>    decon_atomic_disable+0x58/0xd4
> >>>>>    decon_unbind+0x1c/0x3c
> >>>>>    component_unbind+0x38/0x60
> >>>>>    component_bind_all+0x16c/0x25c
> >>>>>    exynos_drm_bind+0x104/0x1bc
> >>>>>    try_to_bring_up_master+0x164/0x1d0
> >>>>>    __component_add+0xa8/0x174
> >>>>>    component_add+0x14/0x20
> >>>>>    hdmi_probe+0x438/0x710
> >>>>>    platform_probe+0x68/0xe0
> >>>>>    really_probe.part.0+0x9c/0x31c
> >>>>>    __driver_probe_device+0x98/0x144
> >>>>>    driver_probe_device+0xc8/0x160
> >>>>>    __device_attach_driver+0xb8/0x120
> >>>>>    bus_for_each_drv+0x78/0xd0
> >>>>>    __device_attach+0xd8/0x180
> >>>>>    device_initial_probe+0x14/0x20
> >>>>>    bus_probe_device+0x9c/0xa4
> >>>>>    deferred_probe_work_func+0x88/0xc4
> >>>>>    process_one_work+0x288/0x6f0
> >>>>>    worker_thread+0x74/0x470
> >>>>>    kthread+0x188/0x194
> >>>>>    ret_from_fork+0x10/0x20
> >>>>> Code: 11002042 f9481c61 531e7442 8b020021 (88dffc21)
> >>>>> ---[ end trace d73aff585b108954 ]---
> >>>>> Kernel panic - not syncing: synchronous external abort: Fatal
> >>>>> exception
> >>>>> SMP: stopping secondary CPUs
> >>>>> Kernel Offset: disabled
> >>>>> CPU features: 0x2,300071c2,00000846
> >>>>> Memory Limit: none
> >>>>> ---[ end Kernel panic - not syncing: synchronous external abort:
> >>>>> Fatal
> >>>>> exception ]---
> >>>> Is this with Bridge or normal DSI panel?
> >>> Can you apply this patch and check?
> >>> https://protect2.fireeye.com/v1/url?k=aad62f08-f54d1627-aad7a447-0cc47a31cdf8-ea5858ddb7f0ecfe&q=1&e=2d730862-2c56-4988-a252-8febd02da578&u=https%3A%2F%2Fgithub.com%2Fopenedev%2Flinux%2Fcommit%2F412f226acd774356e8188c9e62b653672926ee0d
> >>>
> >> Any news on this? just asking in case if you missed it.
> >
> > It is somehow better. System doesn't crash, but the DRM is not bound:
> >
> > # cat /sys/kernel/debug/device_component/exynos-drm
> > master name                                            status
> > -------------------------------------------------------------
> > exynos-drm                                          not bound
> >
> > device name                                            status
> > -------------------------------------------------------------
> > 13800000.decon                                      not bound
> > 13880000.decon                                      not bound
> > 13930000.mic                                        not bound
> > (unknown)                                      not registered
> > (unknown)                                      not registered
> >
> Well, I also checked a much simpler case, the Samsung Trats board
> (arch/arm/boot/dts/exynos4210-trats.dts). It has only Exynos FIMD
> (CRTC), Exynos DSI (encoder) and s6e8aa0 panel. No bridges at all. With
> only the $subject patch applied I got the following errors:
>
> exynos4-fb 11c00000.fimd: Adding to iommu group 0
> OF: graph: no port node found in /soc/fimd at 11c00000
> [drm] Exynos DRM: using 11c00000.fimd device for DMA mapping operations
> exynos-drm exynos-drm: bound 11c00000.fimd (ops fimd_component_ops)
> [drm:drm_bridge_attach] *ERROR* failed to attach bridge
> /soc/dsi at 11c80000 to encoder TMDS-50: -22
> exynos-drm exynos-drm: failed to bind 11c80000.dsi (ops
> exynos_dsi_component_ops): -22
> exynos-drm exynos-drm: master bind failed: -22
> exynos-drm: probe of exynos-drm failed with error -22
> lima 13000000.gpu: gp - mali400 version major 1 minor 1
> lima 13000000.gpu: pp0 - mali400 version major 1 minor 1
> lima 13000000.gpu: pp1 - mali400 version major 1 minor 1
> lima 13000000.gpu: pp2 - mali400 version major 1 minor 1
> lima 13000000.gpu: pp3 - mali400 version major 1 minor 1
> lima 13000000.gpu: l2 cache 128K, 4-way, 64byte cache line, 64bit
> external bus
> lima 13000000.gpu: bus rate = 200000000
> lima 13000000.gpu: mod rate = 100000000
> lima 13000000.gpu: dev_pm_opp_set_regulators: no regulator (mali) found: -19
> [drm] Initialized lima 1.1.0 20191231 for 13000000.gpu on minor 0
>
>
> After applying "drm: exynos: dsi: Add component only once DSI device
> attached" the Exynos DRM is not even tried to bind:
>
> # dmesg | grep drm
> [    2.495898] [drm] Initialized lima 1.1.0 20191231 for 13000000.gpu on
> minor 0

I can see this patch is merged in drm-misc [1], not sure why? because
we are in v4 of this series[2] and this patch certainly broke the
exynos DSI  Let me know what I need to do for next version to send-up?

[1] https://cgit.freedesktop.org/drm/drm-misc/commit/?id=92e794fab87af0793403d5e4a547f0be94a0e656
[2] https://patchwork.kernel.org/project/dri-devel/cover/20211215101534.45003-1-jagan@amarulasolutions.com/

Thanks,
Jagan.


More information about the dri-devel mailing list