[Lenny400] [Letux-kernel] JZ4730/Minibook framebuffer driver updates

Daniel Glöckner daniel-gl at gmx.net
Sun Sep 10 19:55:18 CEST 2017


On Sun, Sep 10, 2017 at 07:31:44PM +0200, H. Nikolaus Schaller wrote:
> Let's think about where limitations could be...
> 1. the total card size may be limited by file system but FAT and ext can
>    handle big file systems
> 2. the raw MMC driver treats the card as single big file with partitions
>     - but there I am not aware of limits
> 3. the partition manager might ot be able to handle big partitions - but
>    this works well on ARM - why should MIPS be different?
> 4. there might be a limit in the MMC controller inside the JZ4730 and the
>    raw MMC driver that it can't send big block addresses automatically.
>    It would only a problem if the MMC controller has e.g. a 16 or 24 bit
>    register for block address and there is a "read block" command and
>    everything else is done by DMA. Then, an old controller can never send
>    "extended" addresses going beyond the card's capabilities to the card.

5. The U-Boot that we don't dare to replace might be too old to load the
   kernel from an SDHC card.

I've been following the recent activities on this mailing list and I really
hope it will lead to mainline support for this device. But did I understand
correctly that all of the work so far has been done without booting the new

Best regards,


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