[U-Boot] [PATCH 0/17] tegra: Add display driver and LCD support for Seaboard

[Simon Glass]

+Tom, Stephen

On Tue, Jul 17, 2012 at 5:11 PM, Thierry Reding
<thierry.reding at avionic-design.de> wrote:
> On Sat, Jul 14, 2012 at 10:03:31AM +0200, Simon Glass wrote:
>> Hi Christian,
>>
>> On Thu, Apr 19, 2012 at 2:41 PM, Christian Kroehnert
>> <christian.kroehnert at avionic-design.de> wrote:
>> > On 15.01.2012 01:47, Simon Glass wrote:
>> >>
>> >> This series adds support for the Tegra2x's display peripheral. This
>> >> supports the LCD display on Seaboard and we use this to enable console
>> >> output in U-Boot on the LCD.
>> >>
>> >> Configuration is via the device tree. Proposed bindings are included
>> >> in this series.
>> >>
>> >> To improve performance two optimisations are offered:
>> >>
>> >> 1. The LCD frame buffer is cached, with the cache being flushed after
>> >> each call puts(). This dramatically increases performance (around 10x).
>> >> This requires a few additions to the ARM cache support.
>> >>
>> >> 2. The console supports scrolling in steps of more than 1 line. This
>> >> speeds up scrolling output considerably, particularly commands like
>> >> 'printenv' which display a lot of output. This requires a new CONFIG
>> >> and a change to the console_scrollup() function.
>> >>
>> >>
>> >> Mayuresh Kulkarni (1):
>> >>    tegra: Enable display/lcd support on Seaboard
>> >>
>> >> Simon Glass (15):
>> >>    fdt: Add function to look up a phandle's register address
>> >>    fdt: Add header guard to fdtdec.h
>> >>    fdt: Correct GPIO name access in fdtdec
>> >>    tegra: Add display support to funcmux
>> >>    tegra: fdt: Add LCD definitions for Tegra
>> >>    tegra: Add support for PWFM
>> >>    tegra: Add LCD driver
>> >>    tegra: Add LCD support to Nvidia boards
>> >>    arm: Add control over cachability of memory regions
>> >>    lcd: Add CONFIG_ALIGN_LCD_TO_SECTION to align lcd for MMU
>> >>    lcd: Add support for flushing LCD fb from dcache after update
>> >>    tegra: Align LCD frame buffer to section boundary
>> >>    tegra: Support control of cache settings for LCD
>> >>    tegra: fdt: Add LCD definitions for Seaboard
>> >>    lcd: Add CONSOLE_SCROLL_LINES option to speed console
>> >>
>> >> Wei Ni (1):
>> >>    tegra: Add SOC support for display/lcd
>> >>
>> >>   README                                          |   16 +
>> >>   arch/arm/cpu/armv7/cache_v7.c                   |   11 +
>> >>   arch/arm/cpu/armv7/tegra2/Makefile              |    1 +
>> >>   arch/arm/cpu/armv7/tegra2/display.c             |  271 +++++++++++
>> >>   arch/arm/cpu/armv7/tegra2/funcmux.c             |   39 ++
>> >>   arch/arm/cpu/armv7/tegra2/pwfm.c                |   40 ++
>> >>   arch/arm/dts/tegra20.dtsi                       |   25 +
>> >>   arch/arm/include/asm/arch-tegra2/dc.h           |  544
>> >> +++++++++++++++++++++++
>> >>   arch/arm/include/asm/arch-tegra2/display.h      |  133 ++++++
>> >>   arch/arm/include/asm/arch-tegra2/pwfm.h         |   54 +++
>> >>   arch/arm/include/asm/system.h                   |   30 ++
>> >>   arch/arm/lib/cache-cp15.c                       |   62 +++-
>> >>   board/nvidia/common/board.c                     |   21 +-
>> >>   board/nvidia/dts/tegra2-seaboard.dts            |   21 +
>> >>   common/cmd_echo.c                               |    3 +-
>> >>   common/lcd.c                                    |   85 +++-
>> >>   doc/device-tree-bindings/video/nvidia-video.txt |   92 ++++
>> >>   drivers/video/Makefile                          |    1 +
>> >>   drivers/video/tegra.c                           |  388 ++++++++++++++++
>> >>   include/configs/seaboard.h                      |   12 +-
>> >>   include/configs/tegra2-common.h                 |    1 +
>> >>   include/fdtdec.h                                |   17 +
>> >>   include/lcd.h                                   |   11 +
>> >>   lib/fdtdec.c                                    |   15 +-
>> >>   24 files changed, 1862 insertions(+), 31 deletions(-)
>> >>   create mode 100644 arch/arm/cpu/armv7/tegra2/display.c
>> >>   create mode 100644 arch/arm/cpu/armv7/tegra2/pwfm.c
>> >>   create mode 100644 arch/arm/include/asm/arch-tegra2/dc.h
>> >>   create mode 100644 arch/arm/include/asm/arch-tegra2/display.h
>> >>   create mode 100644 arch/arm/include/asm/arch-tegra2/pwfm.h
>> >>   create mode 100644 doc/device-tree-bindings/video/nvidia-video.txt
>> >>   create mode 100644 drivers/video/tegra.c
>> >>
>> >
>> > Hi Simon,
>> >
>> > I have added your patch sources manually into the "Prepare v2012.04-rc1
>> > release", because I got errors at apply. Also I added a device tree source
>> > file for Harmony.
>> >
>> > I tested the device tree source file for Harmony and your patch sources on
>> > our Harmony hardware and generated a new patch file:
>> >
>> > http://poeggi.dotsec.net/nvidia/uboot-lvds-init-patch/0001-Add-display-driver-and-LCD-support-for-Harmony-board.patch
>> >
>> > I hope it's all okay, this my first patch release.
>> >
>> > In the display.c source file I implemented a bug fix, because I get garbled
>> > images on the LCD without this fix.
>>
>> I see this code:
>>
>>       u32 m_value;
>>
>>       m_value = readl(0x54202e04);
>>       m_value &= ~0x2;
>>       writel(m_value, 0x54202e04);
>>
>> What register are you actually writing here? I can't find it in my
>> manual, but maybe I just haven't seen that address.
>
> At the time I did look for that register as well but couldn't find
> anything. But I believe that we saw the garbled display issue that
> has been mentioned in another thread. If I remember correctly this
> particular register write was the fix for it.
>
> But I wasn't very much involved at the time, so maybe Christian can
> clarify. However I was going to test your newest version of the LCD
> patch series on our hardware and see if the issue is still there.

Does anyone know what this register is for? I am reluctant to add this
code to the patch without at least a comment.

>
> Thierry

Regards,
Simon