[v12,0/2] drm: add kms driver for loongson display controller

  Loongson display controller IP has been integrated in both Loongson north
bridge chipset(ls7a1000/ls7a2000) and Loongson SoCs(ls2k1000/ls2k2000), it
has been even included in Loongson self-made BMC products.

This display controller is a PCI device. It has two display pipes and each
display pipe support a primary plane and a cursor plane. For the DC in the
ls7a1000 and ls2k1000, each display pipe has a DVO output interface which
provide RGB888 signals, vertical & horizontal synchronisations and pixel
clock. Each CRTC is able to support 1920x1080@60Hz, the maximum resolution
of each display pipe is 2048x2048 according to the hardware spec.

For the DC in LS7A2000, each display pipe is equipped with a built-in HDMI
encoder which is compliant with the HDMI 1.4 specification, thus it support
3840x2160@30Hz. The first display pipe is also equipped with a transparent
vga encoder which is parallel with the HDMI encoder. The DC in LS7A2000 is
more complete compare with the one in old chips, besides above feature, it
has two hardware cursors, two hardware vblank counter and two scanout
position recorders unit. It also support tiled framebuffer format which
can be scanout the tiled framebuffer rendered by the LoongGPU directly.

v1 -> v2:
 1) Use hpd status reg when polling for ls7a2000
 2) Fix all warnings emerged when compile with W=1

v2 -> v3:
 1) Add COMPILE_TEST in Kconfig and make the driver off by default
 2) Alphabetical sorting headers (Thomas)
 3) Untangle register access functions as much as possible (Thomas)
 4) Switch to TTM based memory manager and prefer cached mapping
    for Loongson SoC (Thomas)
 5) Add chip id detection method, now all models are distinguishable.
 6) Revise builtin HDMI phy driver, nearly all main stream mode
    below 4K@30Hz is tested, this driver supported these mode very
    well including clone display mode and extend display mode.

v3 -> v4:
 1) Quickly fix a small mistake.

v4 -> v5:
 1) Drop potential support for Loongson 2K series SoC temporary,
    this part should be resend with the DT binding patch in the future.
 2) Add per display pipe debugfs support to the builtin HDMI encoder.
 3) Rewrite atomic_update() for hardware cursors plane(Thomas)
 4) Rewrite encoder and connector initialization part, untangle it
    according to the chip(Thomas).

v5 -> v6:
 1) Remove stray code which didn't get used, say lsdc_of_get_reserved_ram
 2) Fix all typos I could found, make sentences and code more readable
 3) Untangle lsdc_hdmi*_connector_detect() function according to the pipe
 4) After a serious consideration, we rename this driver as loongson.
    Because we also have drivers toward the LoongGPU IP in LS7A2000 and
    LS2K2000. Besides, there are also drivers about the external encoder,
    HDMI audio driver and vbios support etc. This patch only provide DC
    driver part, my teammate Li Yi believe that loongson will be more
    suitable for loongson graphics than lsdc in the long run.

    loongson.ko = LSDC + LoongGPU + encoders driver + vbios/DT ...

v6 -> v7:
 1) Add prime support, self-sharing is works. sharing buffer with etnaviv
    is also tested, and its works with limitation.
 2) Implement buffer objects tracking with list_head.
 3) S3(sleep to RAM) is tested on ls3a5000+ls7a2000 evb and it works.
 4) Rewrite lsdc_bo_move, since ttm core stop allocating resources
    during BO creation. Patch V1 ~ V6 of this series no longer works
    on latest kernel. Thus, we send V7 to revival them.

v7 -> v8:
 1) Zero a compile warnnings on 32-bit platform, compile with W=1
 2) Revise lsdc_bo_gpu_offset() and minor cleanup
 3) Pageflip tested on the virtual terminal with following commands

    modetest -M loongson -s 32:1920x1080 -v
    modetest -M loongson -s 34:1920x1080 -v -F tiles

   It works like a charm, when running pageflip test with dual screnn
   configuration, another two additional bo created by the modetest
   emerged, VRAM usage up to 40+MB, well we have at least 64MB, still
   enough.

   # cat bos

       bo[0000]: size:     8112kB VRAM
       bo[0001]: size:       16kB VRAM
       bo[0002]: size:       16kB VRAM
       bo[0003]: size:    16208kB VRAM
       bo[0004]: size:     8112kB VRAM
       bo[0005]: size:     8112kB VRAM

v8 -> v9:
 1) Select I2C and I2C_ALGOBIT in Kconfig and should depend on MMU.
 2) Using pci_get_domain_bus_and_slot to get the GPU device.
 3) Other minor improvements.

 Those patches are tested on ls3a5000 + ls7a1000 CRB, ls3a5000 + ls7a2000
 evb, and lemote a1901 board(ls3a4000 + ls7a1000). On loongson mips CPU,
 the write combine support should be enabled, to get a decent performance
 for writing framebuffer data to the VRAM.

v9 -> v10:
 1) Revise lsdc_drm_freeze() to implement S3 completely and correctly.
    I suddenly realized that pinned buffer can not move and VRAM lost
    power when sleep to RAM. Thus, the data in the buffer who is pinned
    in VRAM will get lost when resume. Yet it's not big problem because
    we are software rendering solution which relay on the CPU update the
    front framebuffer. We can see the garbage data when resume from S3,
    but the screen will show correct image as I move the cursor. This is
    due to the cpu repaint. v10 of this patch make S3 perfect by unpin
    all of BOs in VRAM, evict them all to system RAM.

v10 -> v11:
 1) On double screen case, the single giant framebuffer is referenced by
    two GEM object, hence, it will be pinned by prepare_fb() at lease two
    times. This cause its pin count > 1. V10 of this patch only unpin VRAM
    BOs once when suspend, which is not correct on double screen case. V11
    of this patch unpin BOs until its pin count reach to zero when suspend.
    Then, we make the S3 support complete finally. With v11, I can't see
    any garbage data after resume. Teste on both ls7a1000 and ls7a2000
    platform, with single screen and double screen configuration tested.
 2) Fix vblank wait timeout when disable CRTC.
 3) Test against IGT, at least fbdev test and kms_flip test of it passed,
    while most tests of it passed.
 4) Rewrite pixel PLL update function, magic numbers eliminated (Emil)
 5) Drop a few common hardware features description in lsdc_desc (Emil)
 6) Drop lsdc_mode_config_mode_valid(), instead add restrictions in dumb
    create function. (Emil)
 7) Untangle the ls7a1000 case and ls7a2000 case completely (Thomas)

v11 -> v12:
 none

Sui Jingfeng (2):
  MAINTAINERS: add maintainers for DRM LOONGSON driver
  drm: add kms driver for loongson display controller

 MAINTAINERS                                 |    7 +
 drivers/gpu/drm/Kconfig                     |    2 +
 drivers/gpu/drm/Makefile                    |    1 +
 drivers/gpu/drm/loongson/Kconfig            |   17 +
 drivers/gpu/drm/loongson/Makefile           |   19 +
 drivers/gpu/drm/loongson/ls7a1000_outputs.c |  160 +++
 drivers/gpu/drm/loongson/ls7a2000_outputs.c |  534 ++++++++++
 drivers/gpu/drm/loongson/lsdc_crtc.c        | 1064 +++++++++++++++++++
 drivers/gpu/drm/loongson/lsdc_debugfs.c     |   78 ++
 drivers/gpu/drm/loongson/lsdc_device.c      |  104 ++
 drivers/gpu/drm/loongson/lsdc_drv.c         |  484 +++++++++
 drivers/gpu/drm/loongson/lsdc_drv.h         |  485 +++++++++
 drivers/gpu/drm/loongson/lsdc_gem.c         |  319 ++++++
 drivers/gpu/drm/loongson/lsdc_gem.h         |   37 +
 drivers/gpu/drm/loongson/lsdc_gfxpll.c      |  199 ++++
 drivers/gpu/drm/loongson/lsdc_gfxpll.h      |   52 +
 drivers/gpu/drm/loongson/lsdc_i2c.c         |  179 ++++
 drivers/gpu/drm/loongson/lsdc_i2c.h         |   29 +
 drivers/gpu/drm/loongson/lsdc_irq.c         |   81 ++
 drivers/gpu/drm/loongson/lsdc_irq.h         |   16 +
 drivers/gpu/drm/loongson/lsdc_output.h      |   21 +
 drivers/gpu/drm/loongson/lsdc_pixpll.c      |  485 +++++++++
 drivers/gpu/drm/loongson/lsdc_pixpll.h      |   86 ++
 drivers/gpu/drm/loongson/lsdc_plane.c       |  639 +++++++++++
 drivers/gpu/drm/loongson/lsdc_probe.c       |   56 +
 drivers/gpu/drm/loongson/lsdc_probe.h       |   12 +
 drivers/gpu/drm/loongson/lsdc_regs.h        |  400 +++++++
 drivers/gpu/drm/loongson/lsdc_ttm.c         |  547 ++++++++++
 drivers/gpu/drm/loongson/lsdc_ttm.h         |   88 ++
 29 files changed, 6201 insertions(+)
 create mode 100644 drivers/gpu/drm/loongson/Kconfig
 create mode 100644 drivers/gpu/drm/loongson/Makefile
 create mode 100644 drivers/gpu/drm/loongson/ls7a1000_outputs.c
 create mode 100644 drivers/gpu/drm/loongson/ls7a2000_outputs.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_crtc.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_debugfs.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_device.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_output.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_plane.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_regs.h
 create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.c
 create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.h
  

Hi,



If there are bugs, We will take the responsibility to fix.

Is there any chance to merge this patch?

comments and review are also welcome, help please!


On 2023/5/4 16:04, Sui Jingfeng wrote:
> Loongson display controller IP has been integrated in both Loongson north
> bridge chipset(ls7a1000/ls7a2000) and Loongson SoCs(ls2k1000/ls2k2000), it
> has been even included in Loongson self-made BMC products.
>
> This display controller is a PCI device. It has two display pipes and each
> display pipe support a primary plane and a cursor plane. For the DC in the
> ls7a1000 and ls2k1000, each display pipe has a DVO output interface which
> provide RGB888 signals, vertical & horizontal synchronisations and pixel
> clock. Each CRTC is able to support 1920x1080@60Hz, the maximum resolution
> of each display pipe is 2048x2048 according to the hardware spec.
>
> For the DC in LS7A2000, each display pipe is equipped with a built-in HDMI
> encoder which is compliant with the HDMI 1.4 specification, thus it support
> 3840x2160@30Hz. The first display pipe is also equipped with a transparent
> vga encoder which is parallel with the HDMI encoder. The DC in LS7A2000 is
> more complete compare with the one in old chips, besides above feature, it
> has two hardware cursors, two hardware vblank counter and two scanout
> position recorders unit. It also support tiled framebuffer format which
> can be scanout the tiled framebuffer rendered by the LoongGPU directly.
>
> v1 -> v2:
>   1) Use hpd status reg when polling for ls7a2000
>   2) Fix all warnings emerged when compile with W=1
>
> v2 -> v3:
>   1) Add COMPILE_TEST in Kconfig and make the driver off by default
>   2) Alphabetical sorting headers (Thomas)
>   3) Untangle register access functions as much as possible (Thomas)
>   4) Switch to TTM based memory manager and prefer cached mapping
>      for Loongson SoC (Thomas)
>   5) Add chip id detection method, now all models are distinguishable.
>   6) Revise builtin HDMI phy driver, nearly all main stream mode
>      below 4K@30Hz is tested, this driver supported these mode very
>      well including clone display mode and extend display mode.
>
> v3 -> v4:
>   1) Quickly fix a small mistake.
>
> v4 -> v5:
>   1) Drop potential support for Loongson 2K series SoC temporary,
>      this part should be resend with the DT binding patch in the future.
>   2) Add per display pipe debugfs support to the builtin HDMI encoder.
>   3) Rewrite atomic_update() for hardware cursors plane(Thomas)
>   4) Rewrite encoder and connector initialization part, untangle it
>      according to the chip(Thomas).
>
> v5 -> v6:
>   1) Remove stray code which didn't get used, say lsdc_of_get_reserved_ram
>   2) Fix all typos I could found, make sentences and code more readable
>   3) Untangle lsdc_hdmi*_connector_detect() function according to the pipe
>   4) After a serious consideration, we rename this driver as loongson.
>      Because we also have drivers toward the LoongGPU IP in LS7A2000 and
>      LS2K2000. Besides, there are also drivers about the external encoder,
>      HDMI audio driver and vbios support etc. This patch only provide DC
>      driver part, my teammate Li Yi believe that loongson will be more
>      suitable for loongson graphics than lsdc in the long run.
>
>      loongson.ko = LSDC + LoongGPU + encoders driver + vbios/DT ...
>
> v6 -> v7:
>   1) Add prime support, self-sharing is works. sharing buffer with etnaviv
>      is also tested, and its works with limitation.
>   2) Implement buffer objects tracking with list_head.
>   3) S3(sleep to RAM) is tested on ls3a5000+ls7a2000 evb and it works.
>   4) Rewrite lsdc_bo_move, since ttm core stop allocating resources
>      during BO creation. Patch V1 ~ V6 of this series no longer works
>      on latest kernel. Thus, we send V7 to revival them.
>
> v7 -> v8:
>   1) Zero a compile warnnings on 32-bit platform, compile with W=1
>   2) Revise lsdc_bo_gpu_offset() and minor cleanup
>   3) Pageflip tested on the virtual terminal with following commands
>
>      modetest -M loongson -s 32:1920x1080 -v
>      modetest -M loongson -s 34:1920x1080 -v -F tiles
>
>     It works like a charm, when running pageflip test with dual screnn
>     configuration, another two additional bo created by the modetest
>     emerged, VRAM usage up to 40+MB, well we have at least 64MB, still
>     enough.
>
>     # cat bos
>
>         bo[0000]: size:     8112kB VRAM
>         bo[0001]: size:       16kB VRAM
>         bo[0002]: size:       16kB VRAM
>         bo[0003]: size:    16208kB VRAM
>         bo[0004]: size:     8112kB VRAM
>         bo[0005]: size:     8112kB VRAM
>
> v8 -> v9:
>   1) Select I2C and I2C_ALGOBIT in Kconfig and should depend on MMU.
>   2) Using pci_get_domain_bus_and_slot to get the GPU device.
>   3) Other minor improvements.
>
>   Those patches are tested on ls3a5000 + ls7a1000 CRB, ls3a5000 + ls7a2000
>   evb, and lemote a1901 board(ls3a4000 + ls7a1000). On loongson mips CPU,
>   the write combine support should be enabled, to get a decent performance
>   for writing framebuffer data to the VRAM.
>
> v9 -> v10:
>   1) Revise lsdc_drm_freeze() to implement S3 completely and correctly.
>      I suddenly realized that pinned buffer can not move and VRAM lost
>      power when sleep to RAM. Thus, the data in the buffer who is pinned
>      in VRAM will get lost when resume. Yet it's not big problem because
>      we are software rendering solution which relay on the CPU update the
>      front framebuffer. We can see the garbage data when resume from S3,
>      but the screen will show correct image as I move the cursor. This is
>      due to the cpu repaint. v10 of this patch make S3 perfect by unpin
>      all of BOs in VRAM, evict them all to system RAM.
>
> v10 -> v11:
>   1) On double screen case, the single giant framebuffer is referenced by
>      two GEM object, hence, it will be pinned by prepare_fb() at lease two
>      times. This cause its pin count > 1. V10 of this patch only unpin VRAM
>      BOs once when suspend, which is not correct on double screen case. V11
>      of this patch unpin BOs until its pin count reach to zero when suspend.
>      Then, we make the S3 support complete finally. With v11, I can't see
>      any garbage data after resume. Teste on both ls7a1000 and ls7a2000
>      platform, with single screen and double screen configuration tested.
>   2) Fix vblank wait timeout when disable CRTC.
>   3) Test against IGT, at least fbdev test and kms_flip test of it passed,
>      while most tests of it passed.
>   4) Rewrite pixel PLL update function, magic numbers eliminated (Emil)
>   5) Drop a few common hardware features description in lsdc_desc (Emil)
>   6) Drop lsdc_mode_config_mode_valid(), instead add restrictions in dumb
>      create function. (Emil)
>   7) Untangle the ls7a1000 case and ls7a2000 case completely (Thomas)
>
> v11 -> v12:
>   none
>
> Sui Jingfeng (2):
>    MAINTAINERS: add maintainers for DRM LOONGSON driver
>    drm: add kms driver for loongson display controller
>
>   MAINTAINERS                                 |    7 +
>   drivers/gpu/drm/Kconfig                     |    2 +
>   drivers/gpu/drm/Makefile                    |    1 +
>   drivers/gpu/drm/loongson/Kconfig            |   17 +
>   drivers/gpu/drm/loongson/Makefile           |   19 +
>   drivers/gpu/drm/loongson/ls7a1000_outputs.c |  160 +++
>   drivers/gpu/drm/loongson/ls7a2000_outputs.c |  534 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_crtc.c        | 1064 +++++++++++++++++++
>   drivers/gpu/drm/loongson/lsdc_debugfs.c     |   78 ++
>   drivers/gpu/drm/loongson/lsdc_device.c      |  104 ++
>   drivers/gpu/drm/loongson/lsdc_drv.c         |  484 +++++++++
>   drivers/gpu/drm/loongson/lsdc_drv.h         |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_gem.c         |  319 ++++++
>   drivers/gpu/drm/loongson/lsdc_gem.h         |   37 +
>   drivers/gpu/drm/loongson/lsdc_gfxpll.c      |  199 ++++
>   drivers/gpu/drm/loongson/lsdc_gfxpll.h      |   52 +
>   drivers/gpu/drm/loongson/lsdc_i2c.c         |  179 ++++
>   drivers/gpu/drm/loongson/lsdc_i2c.h         |   29 +
>   drivers/gpu/drm/loongson/lsdc_irq.c         |   81 ++
>   drivers/gpu/drm/loongson/lsdc_irq.h         |   16 +
>   drivers/gpu/drm/loongson/lsdc_output.h      |   21 +
>   drivers/gpu/drm/loongson/lsdc_pixpll.c      |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_pixpll.h      |   86 ++
>   drivers/gpu/drm/loongson/lsdc_plane.c       |  639 +++++++++++
>   drivers/gpu/drm/loongson/lsdc_probe.c       |   56 +
>   drivers/gpu/drm/loongson/lsdc_probe.h       |   12 +
>   drivers/gpu/drm/loongson/lsdc_regs.h        |  400 +++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.c         |  547 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.h         |   88 ++
>   29 files changed, 6201 insertions(+)
>   create mode 100644 drivers/gpu/drm/loongson/Kconfig
>   create mode 100644 drivers/gpu/drm/loongson/Makefile
>   create mode 100644 drivers/gpu/drm/loongson/ls7a1000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/ls7a2000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_crtc.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_debugfs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_device.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_output.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_plane.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_regs.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.h
>
  

This patch is tested against IGT,


1) fbdev test passed


IGT-Version: 1.27.1-gce91d123 (loongarch64) (Linux: 6.3.0+ loongarch64)
Starting subtest: info
Subtest info: SUCCESS (0.000s)
Starting subtest: pan
Subtest pan: SUCCESS (0.042s)
Starting subtest: read
Subtest read: SUCCESS (0.012s)
Starting subtest: unaligned-read
Subtest unaligned-read: SUCCESS (0.003s)
Starting subtest: write
Subtest write: SUCCESS (0.024s)
Starting subtest: unaligned-write
Subtest unaligned-write: SUCCESS (0.003s)
Starting subtest: eof
Subtest eof: SUCCESS (0.000s)
Starting subtest: nullptr
Subtest nullptr: SUCCESS (0.000s)


2) fbtest from geert also show good results:


Using drawops cfb32 (32 bpp packed pixels)
Available visuals:
   Monochrome
   Grayscale 256
   Truecolor 8:8:8:0
Using visops truecolor
Running all tests
test001: PASSED
test002: PASSED
test003: PASSED
test004: PASSED
test005: PASSED
test006: PASSED
test008: PASSED
test009: PASSED
test010: PASSED
Benchmarking... 10x10 squares: 461.49 Mpixels/s
Benchmarking... 20x20 squares: 984.74 Mpixels/s
Benchmarking... 50x50 squares: 2253.04 Mpixels/s
Benchmarking... 100x100 squares: 2218.78 Mpixels/s
Benchmarking... 200x200 squares: 2880.41 Mpixels/s
Benchmarking... 500x500 squares: 3642.36 Mpixels/s
Benchmarking... 1000x1000 squares: 3931.25 Mpixels/s
test012: PASSED
Benchmarking... R5 circles: 258.73 Mpixels/s
Benchmarking... R10 circles: 605.78 Mpixels/s
Benchmarking... R25 circles: 1513.02 Mpixels/s
Benchmarking... R50 circles: 1970.00 Mpixels/s
Benchmarking... R100 circles: 2481.70 Mpixels/s
Benchmarking... R250 circles: 3274.97 Mpixels/s
Benchmarking... R500 circles: 3722.24 Mpixels/s
test013: PASSED


On 2023/5/4 16:04, Sui Jingfeng wrote:
> Loongson display controller IP has been integrated in both Loongson north
> bridge chipset(ls7a1000/ls7a2000) and Loongson SoCs(ls2k1000/ls2k2000), it
> has been even included in Loongson self-made BMC products.
>
> This display controller is a PCI device. It has two display pipes and each
> display pipe support a primary plane and a cursor plane. For the DC in the
> ls7a1000 and ls2k1000, each display pipe has a DVO output interface which
> provide RGB888 signals, vertical & horizontal synchronisations and pixel
> clock. Each CRTC is able to support 1920x1080@60Hz, the maximum resolution
> of each display pipe is 2048x2048 according to the hardware spec.
>
> For the DC in LS7A2000, each display pipe is equipped with a built-in HDMI
> encoder which is compliant with the HDMI 1.4 specification, thus it support
> 3840x2160@30Hz. The first display pipe is also equipped with a transparent
> vga encoder which is parallel with the HDMI encoder. The DC in LS7A2000 is
> more complete compare with the one in old chips, besides above feature, it
> has two hardware cursors, two hardware vblank counter and two scanout
> position recorders unit. It also support tiled framebuffer format which
> can be scanout the tiled framebuffer rendered by the LoongGPU directly.
>
> v1 -> v2:
>   1) Use hpd status reg when polling for ls7a2000
>   2) Fix all warnings emerged when compile with W=1
>
> v2 -> v3:
>   1) Add COMPILE_TEST in Kconfig and make the driver off by default
>   2) Alphabetical sorting headers (Thomas)
>   3) Untangle register access functions as much as possible (Thomas)
>   4) Switch to TTM based memory manager and prefer cached mapping
>      for Loongson SoC (Thomas)
>   5) Add chip id detection method, now all models are distinguishable.
>   6) Revise builtin HDMI phy driver, nearly all main stream mode
>      below 4K@30Hz is tested, this driver supported these mode very
>      well including clone display mode and extend display mode.
>
> v3 -> v4:
>   1) Quickly fix a small mistake.
>
> v4 -> v5:
>   1) Drop potential support for Loongson 2K series SoC temporary,
>      this part should be resend with the DT binding patch in the future.
>   2) Add per display pipe debugfs support to the builtin HDMI encoder.
>   3) Rewrite atomic_update() for hardware cursors plane(Thomas)
>   4) Rewrite encoder and connector initialization part, untangle it
>      according to the chip(Thomas).
>
> v5 -> v6:
>   1) Remove stray code which didn't get used, say lsdc_of_get_reserved_ram
>   2) Fix all typos I could found, make sentences and code more readable
>   3) Untangle lsdc_hdmi*_connector_detect() function according to the pipe
>   4) After a serious consideration, we rename this driver as loongson.
>      Because we also have drivers toward the LoongGPU IP in LS7A2000 and
>      LS2K2000. Besides, there are also drivers about the external encoder,
>      HDMI audio driver and vbios support etc. This patch only provide DC
>      driver part, my teammate Li Yi believe that loongson will be more
>      suitable for loongson graphics than lsdc in the long run.
>
>      loongson.ko = LSDC + LoongGPU + encoders driver + vbios/DT ...
>
> v6 -> v7:
>   1) Add prime support, self-sharing is works. sharing buffer with etnaviv
>      is also tested, and its works with limitation.
>   2) Implement buffer objects tracking with list_head.
>   3) S3(sleep to RAM) is tested on ls3a5000+ls7a2000 evb and it works.
>   4) Rewrite lsdc_bo_move, since ttm core stop allocating resources
>      during BO creation. Patch V1 ~ V6 of this series no longer works
>      on latest kernel. Thus, we send V7 to revival them.
>
> v7 -> v8:
>   1) Zero a compile warnnings on 32-bit platform, compile with W=1
>   2) Revise lsdc_bo_gpu_offset() and minor cleanup
>   3) Pageflip tested on the virtual terminal with following commands
>
>      modetest -M loongson -s 32:1920x1080 -v
>      modetest -M loongson -s 34:1920x1080 -v -F tiles
>
>     It works like a charm, when running pageflip test with dual screnn
>     configuration, another two additional bo created by the modetest
>     emerged, VRAM usage up to 40+MB, well we have at least 64MB, still
>     enough.
>
>     # cat bos
>
>         bo[0000]: size:     8112kB VRAM
>         bo[0001]: size:       16kB VRAM
>         bo[0002]: size:       16kB VRAM
>         bo[0003]: size:    16208kB VRAM
>         bo[0004]: size:     8112kB VRAM
>         bo[0005]: size:     8112kB VRAM
>
> v8 -> v9:
>   1) Select I2C and I2C_ALGOBIT in Kconfig and should depend on MMU.
>   2) Using pci_get_domain_bus_and_slot to get the GPU device.
>   3) Other minor improvements.
>
>   Those patches are tested on ls3a5000 + ls7a1000 CRB, ls3a5000 + ls7a2000
>   evb, and lemote a1901 board(ls3a4000 + ls7a1000). On loongson mips CPU,
>   the write combine support should be enabled, to get a decent performance
>   for writing framebuffer data to the VRAM.
>
> v9 -> v10:
>   1) Revise lsdc_drm_freeze() to implement S3 completely and correctly.
>      I suddenly realized that pinned buffer can not move and VRAM lost
>      power when sleep to RAM. Thus, the data in the buffer who is pinned
>      in VRAM will get lost when resume. Yet it's not big problem because
>      we are software rendering solution which relay on the CPU update the
>      front framebuffer. We can see the garbage data when resume from S3,
>      but the screen will show correct image as I move the cursor. This is
>      due to the cpu repaint. v10 of this patch make S3 perfect by unpin
>      all of BOs in VRAM, evict them all to system RAM.
>
> v10 -> v11:
>   1) On double screen case, the single giant framebuffer is referenced by
>      two GEM object, hence, it will be pinned by prepare_fb() at lease two
>      times. This cause its pin count > 1. V10 of this patch only unpin VRAM
>      BOs once when suspend, which is not correct on double screen case. V11
>      of this patch unpin BOs until its pin count reach to zero when suspend.
>      Then, we make the S3 support complete finally. With v11, I can't see
>      any garbage data after resume. Teste on both ls7a1000 and ls7a2000
>      platform, with single screen and double screen configuration tested.
>   2) Fix vblank wait timeout when disable CRTC.
>   3) Test against IGT, at least fbdev test and kms_flip test of it passed,
>      while most tests of it passed.
>   4) Rewrite pixel PLL update function, magic numbers eliminated (Emil)
>   5) Drop a few common hardware features description in lsdc_desc (Emil)
>   6) Drop lsdc_mode_config_mode_valid(), instead add restrictions in dumb
>      create function. (Emil)
>   7) Untangle the ls7a1000 case and ls7a2000 case completely (Thomas)
>
> v11 -> v12:
>   none
>
> Sui Jingfeng (2):
>    MAINTAINERS: add maintainers for DRM LOONGSON driver
>    drm: add kms driver for loongson display controller
>
>   MAINTAINERS                                 |    7 +
>   drivers/gpu/drm/Kconfig                     |    2 +
>   drivers/gpu/drm/Makefile                    |    1 +
>   drivers/gpu/drm/loongson/Kconfig            |   17 +
>   drivers/gpu/drm/loongson/Makefile           |   19 +
>   drivers/gpu/drm/loongson/ls7a1000_outputs.c |  160 +++
>   drivers/gpu/drm/loongson/ls7a2000_outputs.c |  534 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_crtc.c        | 1064 +++++++++++++++++++
>   drivers/gpu/drm/loongson/lsdc_debugfs.c     |   78 ++
>   drivers/gpu/drm/loongson/lsdc_device.c      |  104 ++
>   drivers/gpu/drm/loongson/lsdc_drv.c         |  484 +++++++++
>   drivers/gpu/drm/loongson/lsdc_drv.h         |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_gem.c         |  319 ++++++
>   drivers/gpu/drm/loongson/lsdc_gem.h         |   37 +
>   drivers/gpu/drm/loongson/lsdc_gfxpll.c      |  199 ++++
>   drivers/gpu/drm/loongson/lsdc_gfxpll.h      |   52 +
>   drivers/gpu/drm/loongson/lsdc_i2c.c         |  179 ++++
>   drivers/gpu/drm/loongson/lsdc_i2c.h         |   29 +
>   drivers/gpu/drm/loongson/lsdc_irq.c         |   81 ++
>   drivers/gpu/drm/loongson/lsdc_irq.h         |   16 +
>   drivers/gpu/drm/loongson/lsdc_output.h      |   21 +
>   drivers/gpu/drm/loongson/lsdc_pixpll.c      |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_pixpll.h      |   86 ++
>   drivers/gpu/drm/loongson/lsdc_plane.c       |  639 +++++++++++
>   drivers/gpu/drm/loongson/lsdc_probe.c       |   56 +
>   drivers/gpu/drm/loongson/lsdc_probe.h       |   12 +
>   drivers/gpu/drm/loongson/lsdc_regs.h        |  400 +++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.c         |  547 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.h         |   88 ++
>   29 files changed, 6201 insertions(+)
>   create mode 100644 drivers/gpu/drm/loongson/Kconfig
>   create mode 100644 drivers/gpu/drm/loongson/Makefile
>   create mode 100644 drivers/gpu/drm/loongson/ls7a1000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/ls7a2000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_crtc.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_debugfs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_device.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_output.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_plane.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_regs.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.h
>
  

kms_flip test simple of IGT run finished,  a few tail lines of the full 
log is pasted here.

as following:


Dynamic subtest AB-HDMI-A1-HDMI-A2: FAIL (0.771s)
Subtest 2x-modeset-vs-vblank-race-interruptible: FAIL (0.771s)
Starting subtest: bo-too-big-interruptible
Starting dynamic subtest: A-HDMI-A1
Test requirement not met in function __run_test_on_crtc_set, file 
../tests/kms_flip.c:1356:
Test requirement: !(!is_i915_device(drm_fd))
Dynamic subtest A-HDMI-A1: SKIP (0.000s)
Starting dynamic subtest: B-HDMI-A2
Test requirement not met in function __run_test_on_crtc_set, file 
../tests/kms_flip.c:1356:
Test requirement: !(!is_i915_device(drm_fd))
Dynamic subtest B-HDMI-A2: SKIP (0.000s)
No dynamic tests executed.
Subtest bo-too-big-interruptible: SKIP (0.001s)
Starting subtest: flip-vs-suspend-interruptible
Starting dynamic subtest: A-HDMI-A1
   1920x1080 60 1920 2008 2052 2200 1080 1084 1089 1125 0x5 0x48 148500
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:20:16 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:20:45 2023
Dynamic subtest A-HDMI-A1: SUCCESS (12.293s)
Starting dynamic subtest: B-HDMI-A2
   1920x1080 60 1920 2008 2052 2100 1080 1084 1089 1125 0x5 0x48 141750
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:21:14 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:21:43 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:22:12 2023
Dynamic subtest B-HDMI-A2: SUCCESS (7.487s)
Subtest flip-vs-suspend-interruptible: SUCCESS (19.781s)
Starting subtest: 2x-flip-vs-suspend-interruptible
Starting dynamic subtest: AB-HDMI-A1-HDMI-A2
   1920x1080 60 1920 2008 2052 2200 1080 1084 1089 1125 0x5 0x48 148500
   1920x1080 60 1920 2008 2052 2100 1080 1084 1089 1125 0x5 0x48 141750
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:22:41 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:23:10 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:23:39 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:24:08 2023
[cmd] rtcwake: wakeup from "mem" using /dev/rtc0 at Mon May  8 03:24:37 2023
Dynamic subtest AB-HDMI-A1-HDMI-A2: SUCCESS (12.605s)
Subtest 2x-flip-vs-suspend-interruptible: SUCCESS (12.605s)


Compared with V10, No hang, no vblank wait timeout call trace happen.

suspend and resume is always successful, thus, V12 is far better than V10,

there still some test case failed,  but it seem that it is not relevant.

May I fix those problem after this patch landed?  the tests simple of 
IGT is heavy.


On 2023/5/4 16:04, Sui Jingfeng wrote:
> Loongson display controller IP has been integrated in both Loongson north
> bridge chipset(ls7a1000/ls7a2000) and Loongson SoCs(ls2k1000/ls2k2000), it
> has been even included in Loongson self-made BMC products.
>
> This display controller is a PCI device. It has two display pipes and each
> display pipe support a primary plane and a cursor plane. For the DC in the
> ls7a1000 and ls2k1000, each display pipe has a DVO output interface which
> provide RGB888 signals, vertical & horizontal synchronisations and pixel
> clock. Each CRTC is able to support 1920x1080@60Hz, the maximum resolution
> of each display pipe is 2048x2048 according to the hardware spec.
>
> For the DC in LS7A2000, each display pipe is equipped with a built-in HDMI
> encoder which is compliant with the HDMI 1.4 specification, thus it support
> 3840x2160@30Hz. The first display pipe is also equipped with a transparent
> vga encoder which is parallel with the HDMI encoder. The DC in LS7A2000 is
> more complete compare with the one in old chips, besides above feature, it
> has two hardware cursors, two hardware vblank counter and two scanout
> position recorders unit. It also support tiled framebuffer format which
> can be scanout the tiled framebuffer rendered by the LoongGPU directly.
>
> v1 -> v2:
>   1) Use hpd status reg when polling for ls7a2000
>   2) Fix all warnings emerged when compile with W=1
>
> v2 -> v3:
>   1) Add COMPILE_TEST in Kconfig and make the driver off by default
>   2) Alphabetical sorting headers (Thomas)
>   3) Untangle register access functions as much as possible (Thomas)
>   4) Switch to TTM based memory manager and prefer cached mapping
>      for Loongson SoC (Thomas)
>   5) Add chip id detection method, now all models are distinguishable.
>   6) Revise builtin HDMI phy driver, nearly all main stream mode
>      below 4K@30Hz is tested, this driver supported these mode very
>      well including clone display mode and extend display mode.
>
> v3 -> v4:
>   1) Quickly fix a small mistake.
>
> v4 -> v5:
>   1) Drop potential support for Loongson 2K series SoC temporary,
>      this part should be resend with the DT binding patch in the future.
>   2) Add per display pipe debugfs support to the builtin HDMI encoder.
>   3) Rewrite atomic_update() for hardware cursors plane(Thomas)
>   4) Rewrite encoder and connector initialization part, untangle it
>      according to the chip(Thomas).
>
> v5 -> v6:
>   1) Remove stray code which didn't get used, say lsdc_of_get_reserved_ram
>   2) Fix all typos I could found, make sentences and code more readable
>   3) Untangle lsdc_hdmi*_connector_detect() function according to the pipe
>   4) After a serious consideration, we rename this driver as loongson.
>      Because we also have drivers toward the LoongGPU IP in LS7A2000 and
>      LS2K2000. Besides, there are also drivers about the external encoder,
>      HDMI audio driver and vbios support etc. This patch only provide DC
>      driver part, my teammate Li Yi believe that loongson will be more
>      suitable for loongson graphics than lsdc in the long run.
>
>      loongson.ko = LSDC + LoongGPU + encoders driver + vbios/DT ...
>
> v6 -> v7:
>   1) Add prime support, self-sharing is works. sharing buffer with etnaviv
>      is also tested, and its works with limitation.
>   2) Implement buffer objects tracking with list_head.
>   3) S3(sleep to RAM) is tested on ls3a5000+ls7a2000 evb and it works.
>   4) Rewrite lsdc_bo_move, since ttm core stop allocating resources
>      during BO creation. Patch V1 ~ V6 of this series no longer works
>      on latest kernel. Thus, we send V7 to revival them.
>
> v7 -> v8:
>   1) Zero a compile warnnings on 32-bit platform, compile with W=1
>   2) Revise lsdc_bo_gpu_offset() and minor cleanup
>   3) Pageflip tested on the virtual terminal with following commands
>
>      modetest -M loongson -s 32:1920x1080 -v
>      modetest -M loongson -s 34:1920x1080 -v -F tiles
>
>     It works like a charm, when running pageflip test with dual screnn
>     configuration, another two additional bo created by the modetest
>     emerged, VRAM usage up to 40+MB, well we have at least 64MB, still
>     enough.
>
>     # cat bos
>
>         bo[0000]: size:     8112kB VRAM
>         bo[0001]: size:       16kB VRAM
>         bo[0002]: size:       16kB VRAM
>         bo[0003]: size:    16208kB VRAM
>         bo[0004]: size:     8112kB VRAM
>         bo[0005]: size:     8112kB VRAM
>
> v8 -> v9:
>   1) Select I2C and I2C_ALGOBIT in Kconfig and should depend on MMU.
>   2) Using pci_get_domain_bus_and_slot to get the GPU device.
>   3) Other minor improvements.
>
>   Those patches are tested on ls3a5000 + ls7a1000 CRB, ls3a5000 + ls7a2000
>   evb, and lemote a1901 board(ls3a4000 + ls7a1000). On loongson mips CPU,
>   the write combine support should be enabled, to get a decent performance
>   for writing framebuffer data to the VRAM.
>
> v9 -> v10:
>   1) Revise lsdc_drm_freeze() to implement S3 completely and correctly.
>      I suddenly realized that pinned buffer can not move and VRAM lost
>      power when sleep to RAM. Thus, the data in the buffer who is pinned
>      in VRAM will get lost when resume. Yet it's not big problem because
>      we are software rendering solution which relay on the CPU update the
>      front framebuffer. We can see the garbage data when resume from S3,
>      but the screen will show correct image as I move the cursor. This is
>      due to the cpu repaint. v10 of this patch make S3 perfect by unpin
>      all of BOs in VRAM, evict them all to system RAM.
>
> v10 -> v11:
>   1) On double screen case, the single giant framebuffer is referenced by
>      two GEM object, hence, it will be pinned by prepare_fb() at lease two
>      times. This cause its pin count > 1. V10 of this patch only unpin VRAM
>      BOs once when suspend, which is not correct on double screen case. V11
>      of this patch unpin BOs until its pin count reach to zero when suspend.
>      Then, we make the S3 support complete finally. With v11, I can't see
>      any garbage data after resume. Teste on both ls7a1000 and ls7a2000
>      platform, with single screen and double screen configuration tested.
>   2) Fix vblank wait timeout when disable CRTC.
>   3) Test against IGT, at least fbdev test and kms_flip test of it passed,
>      while most tests of it passed.
>   4) Rewrite pixel PLL update function, magic numbers eliminated (Emil)
>   5) Drop a few common hardware features description in lsdc_desc (Emil)
>   6) Drop lsdc_mode_config_mode_valid(), instead add restrictions in dumb
>      create function. (Emil)
>   7) Untangle the ls7a1000 case and ls7a2000 case completely (Thomas)
>
> v11 -> v12:
>   none
>
> Sui Jingfeng (2):
>    MAINTAINERS: add maintainers for DRM LOONGSON driver
>    drm: add kms driver for loongson display controller
>
>   MAINTAINERS                                 |    7 +
>   drivers/gpu/drm/Kconfig                     |    2 +
>   drivers/gpu/drm/Makefile                    |    1 +
>   drivers/gpu/drm/loongson/Kconfig            |   17 +
>   drivers/gpu/drm/loongson/Makefile           |   19 +
>   drivers/gpu/drm/loongson/ls7a1000_outputs.c |  160 +++
>   drivers/gpu/drm/loongson/ls7a2000_outputs.c |  534 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_crtc.c        | 1064 +++++++++++++++++++
>   drivers/gpu/drm/loongson/lsdc_debugfs.c     |   78 ++
>   drivers/gpu/drm/loongson/lsdc_device.c      |  104 ++
>   drivers/gpu/drm/loongson/lsdc_drv.c         |  484 +++++++++
>   drivers/gpu/drm/loongson/lsdc_drv.h         |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_gem.c         |  319 ++++++
>   drivers/gpu/drm/loongson/lsdc_gem.h         |   37 +
>   drivers/gpu/drm/loongson/lsdc_gfxpll.c      |  199 ++++
>   drivers/gpu/drm/loongson/lsdc_gfxpll.h      |   52 +
>   drivers/gpu/drm/loongson/lsdc_i2c.c         |  179 ++++
>   drivers/gpu/drm/loongson/lsdc_i2c.h         |   29 +
>   drivers/gpu/drm/loongson/lsdc_irq.c         |   81 ++
>   drivers/gpu/drm/loongson/lsdc_irq.h         |   16 +
>   drivers/gpu/drm/loongson/lsdc_output.h      |   21 +
>   drivers/gpu/drm/loongson/lsdc_pixpll.c      |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_pixpll.h      |   86 ++
>   drivers/gpu/drm/loongson/lsdc_plane.c       |  639 +++++++++++
>   drivers/gpu/drm/loongson/lsdc_probe.c       |   56 +
>   drivers/gpu/drm/loongson/lsdc_probe.h       |   12 +
>   drivers/gpu/drm/loongson/lsdc_regs.h        |  400 +++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.c         |  547 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.h         |   88 ++
>   29 files changed, 6201 insertions(+)
>   create mode 100644 drivers/gpu/drm/loongson/Kconfig
>   create mode 100644 drivers/gpu/drm/loongson/Makefile
>   create mode 100644 drivers/gpu/drm/loongson/ls7a1000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/ls7a2000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_crtc.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_debugfs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_device.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_output.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_plane.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_regs.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.h
>
  

ping ?

On 2023/5/4 16:04, Sui Jingfeng wrote:
> Loongson display controller IP has been integrated in both Loongson north
> bridge chipset(ls7a1000/ls7a2000) and Loongson SoCs(ls2k1000/ls2k2000), it
> has been even included in Loongson self-made BMC products.
>
> This display controller is a PCI device. It has two display pipes and each
> display pipe support a primary plane and a cursor plane. For the DC in the
> ls7a1000 and ls2k1000, each display pipe has a DVO output interface which
> provide RGB888 signals, vertical & horizontal synchronisations and pixel
> clock. Each CRTC is able to support 1920x1080@60Hz, the maximum resolution
> of each display pipe is 2048x2048 according to the hardware spec.
>
> For the DC in LS7A2000, each display pipe is equipped with a built-in HDMI
> encoder which is compliant with the HDMI 1.4 specification, thus it support
> 3840x2160@30Hz. The first display pipe is also equipped with a transparent
> vga encoder which is parallel with the HDMI encoder. The DC in LS7A2000 is
> more complete compare with the one in old chips, besides above feature, it
> has two hardware cursors, two hardware vblank counter and two scanout
> position recorders unit. It also support tiled framebuffer format which
> can be scanout the tiled framebuffer rendered by the LoongGPU directly.
>
> v1 -> v2:
>   1) Use hpd status reg when polling for ls7a2000
>   2) Fix all warnings emerged when compile with W=1
>
> v2 -> v3:
>   1) Add COMPILE_TEST in Kconfig and make the driver off by default
>   2) Alphabetical sorting headers (Thomas)
>   3) Untangle register access functions as much as possible (Thomas)
>   4) Switch to TTM based memory manager and prefer cached mapping
>      for Loongson SoC (Thomas)
>   5) Add chip id detection method, now all models are distinguishable.
>   6) Revise builtin HDMI phy driver, nearly all main stream mode
>      below 4K@30Hz is tested, this driver supported these mode very
>      well including clone display mode and extend display mode.
>
> v3 -> v4:
>   1) Quickly fix a small mistake.
>
> v4 -> v5:
>   1) Drop potential support for Loongson 2K series SoC temporary,
>      this part should be resend with the DT binding patch in the future.
>   2) Add per display pipe debugfs support to the builtin HDMI encoder.
>   3) Rewrite atomic_update() for hardware cursors plane(Thomas)
>   4) Rewrite encoder and connector initialization part, untangle it
>      according to the chip(Thomas).
>
> v5 -> v6:
>   1) Remove stray code which didn't get used, say lsdc_of_get_reserved_ram
>   2) Fix all typos I could found, make sentences and code more readable
>   3) Untangle lsdc_hdmi*_connector_detect() function according to the pipe
>   4) After a serious consideration, we rename this driver as loongson.
>      Because we also have drivers toward the LoongGPU IP in LS7A2000 and
>      LS2K2000. Besides, there are also drivers about the external encoder,
>      HDMI audio driver and vbios support etc. This patch only provide DC
>      driver part, my teammate Li Yi believe that loongson will be more
>      suitable for loongson graphics than lsdc in the long run.
>
>      loongson.ko = LSDC + LoongGPU + encoders driver + vbios/DT ...
>
> v6 -> v7:
>   1) Add prime support, self-sharing is works. sharing buffer with etnaviv
>      is also tested, and its works with limitation.
>   2) Implement buffer objects tracking with list_head.
>   3) S3(sleep to RAM) is tested on ls3a5000+ls7a2000 evb and it works.
>   4) Rewrite lsdc_bo_move, since ttm core stop allocating resources
>      during BO creation. Patch V1 ~ V6 of this series no longer works
>      on latest kernel. Thus, we send V7 to revival them.
>
> v7 -> v8:
>   1) Zero a compile warnnings on 32-bit platform, compile with W=1
>   2) Revise lsdc_bo_gpu_offset() and minor cleanup
>   3) Pageflip tested on the virtual terminal with following commands
>
>      modetest -M loongson -s 32:1920x1080 -v
>      modetest -M loongson -s 34:1920x1080 -v -F tiles
>
>     It works like a charm, when running pageflip test with dual screnn
>     configuration, another two additional bo created by the modetest
>     emerged, VRAM usage up to 40+MB, well we have at least 64MB, still
>     enough.
>
>     # cat bos
>
>         bo[0000]: size:     8112kB VRAM
>         bo[0001]: size:       16kB VRAM
>         bo[0002]: size:       16kB VRAM
>         bo[0003]: size:    16208kB VRAM
>         bo[0004]: size:     8112kB VRAM
>         bo[0005]: size:     8112kB VRAM
>
> v8 -> v9:
>   1) Select I2C and I2C_ALGOBIT in Kconfig and should depend on MMU.
>   2) Using pci_get_domain_bus_and_slot to get the GPU device.
>   3) Other minor improvements.
>
>   Those patches are tested on ls3a5000 + ls7a1000 CRB, ls3a5000 + ls7a2000
>   evb, and lemote a1901 board(ls3a4000 + ls7a1000). On loongson mips CPU,
>   the write combine support should be enabled, to get a decent performance
>   for writing framebuffer data to the VRAM.
>
> v9 -> v10:
>   1) Revise lsdc_drm_freeze() to implement S3 completely and correctly.
>      I suddenly realized that pinned buffer can not move and VRAM lost
>      power when sleep to RAM. Thus, the data in the buffer who is pinned
>      in VRAM will get lost when resume. Yet it's not big problem because
>      we are software rendering solution which relay on the CPU update the
>      front framebuffer. We can see the garbage data when resume from S3,
>      but the screen will show correct image as I move the cursor. This is
>      due to the cpu repaint. v10 of this patch make S3 perfect by unpin
>      all of BOs in VRAM, evict them all to system RAM.
>
> v10 -> v11:
>   1) On double screen case, the single giant framebuffer is referenced by
>      two GEM object, hence, it will be pinned by prepare_fb() at lease two
>      times. This cause its pin count > 1. V10 of this patch only unpin VRAM
>      BOs once when suspend, which is not correct on double screen case. V11
>      of this patch unpin BOs until its pin count reach to zero when suspend.
>      Then, we make the S3 support complete finally. With v11, I can't see
>      any garbage data after resume. Teste on both ls7a1000 and ls7a2000
>      platform, with single screen and double screen configuration tested.
>   2) Fix vblank wait timeout when disable CRTC.
>   3) Test against IGT, at least fbdev test and kms_flip test of it passed,
>      while most tests of it passed.
>   4) Rewrite pixel PLL update function, magic numbers eliminated (Emil)
>   5) Drop a few common hardware features description in lsdc_desc (Emil)
>   6) Drop lsdc_mode_config_mode_valid(), instead add restrictions in dumb
>      create function. (Emil)
>   7) Untangle the ls7a1000 case and ls7a2000 case completely (Thomas)
>
> v11 -> v12:
>   none
>
> Sui Jingfeng (2):
>    MAINTAINERS: add maintainers for DRM LOONGSON driver
>    drm: add kms driver for loongson display controller
>
>   MAINTAINERS                                 |    7 +
>   drivers/gpu/drm/Kconfig                     |    2 +
>   drivers/gpu/drm/Makefile                    |    1 +
>   drivers/gpu/drm/loongson/Kconfig            |   17 +
>   drivers/gpu/drm/loongson/Makefile           |   19 +
>   drivers/gpu/drm/loongson/ls7a1000_outputs.c |  160 +++
>   drivers/gpu/drm/loongson/ls7a2000_outputs.c |  534 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_crtc.c        | 1064 +++++++++++++++++++
>   drivers/gpu/drm/loongson/lsdc_debugfs.c     |   78 ++
>   drivers/gpu/drm/loongson/lsdc_device.c      |  104 ++
>   drivers/gpu/drm/loongson/lsdc_drv.c         |  484 +++++++++
>   drivers/gpu/drm/loongson/lsdc_drv.h         |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_gem.c         |  319 ++++++
>   drivers/gpu/drm/loongson/lsdc_gem.h         |   37 +
>   drivers/gpu/drm/loongson/lsdc_gfxpll.c      |  199 ++++
>   drivers/gpu/drm/loongson/lsdc_gfxpll.h      |   52 +
>   drivers/gpu/drm/loongson/lsdc_i2c.c         |  179 ++++
>   drivers/gpu/drm/loongson/lsdc_i2c.h         |   29 +
>   drivers/gpu/drm/loongson/lsdc_irq.c         |   81 ++
>   drivers/gpu/drm/loongson/lsdc_irq.h         |   16 +
>   drivers/gpu/drm/loongson/lsdc_output.h      |   21 +
>   drivers/gpu/drm/loongson/lsdc_pixpll.c      |  485 +++++++++
>   drivers/gpu/drm/loongson/lsdc_pixpll.h      |   86 ++
>   drivers/gpu/drm/loongson/lsdc_plane.c       |  639 +++++++++++
>   drivers/gpu/drm/loongson/lsdc_probe.c       |   56 +
>   drivers/gpu/drm/loongson/lsdc_probe.h       |   12 +
>   drivers/gpu/drm/loongson/lsdc_regs.h        |  400 +++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.c         |  547 ++++++++++
>   drivers/gpu/drm/loongson/lsdc_ttm.h         |   88 ++
>   29 files changed, 6201 insertions(+)
>   create mode 100644 drivers/gpu/drm/loongson/Kconfig
>   create mode 100644 drivers/gpu/drm/loongson/Makefile
>   create mode 100644 drivers/gpu/drm/loongson/ls7a1000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/ls7a2000_outputs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_crtc.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_debugfs.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_device.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_drv.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gem.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_gfxpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_i2c.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_irq.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_output.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_pixpll.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_plane.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_probe.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_regs.h
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.c
>   create mode 100644 drivers/gpu/drm/loongson/lsdc_ttm.h
>