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

[Marek Szyprowski]

Hi Jagan,

On 22.11.2021 15:21, Jagan Teki 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?

This log is from the TM2e board 
(arch/arm64/boot/dts/exynos/exynos5433-tm2e.dts) with a normal DSI panel 
and Exynos MIC bridge between Exynos Decon and Exynos DSI.

Best regards

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