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

[Marek Szyprowski]

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

Best regards

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