[PATCH] SDHC driver for PowerPC QoriQ

[Sebastian Huber]

On 26/07/16 03:17, Nickolay Kolchin wrote:
> 1. We were not aware about existing SDHC driver. We always considered 
> rtems-libbsd an experiment. Is it ready for production use?

Yes, its definitely ready for production use. Its documentation and 
configuration is currently the weak point.

I would prefer to get the SD/MMC card support improved in libbsd instead 
of adding more and more BSP-specific drivers each with its own basic 
support code.

>
> 2. Driver was developed for Kontron P2020 board. Existing errata for 
> this chip (P1020), mentions only "inability to detect sdcard at startup".

For the SDHC you have to be careful with erratas, a good reference is 
the Linux driver "drivers/mmc/host/sdhci-of-esdhc.c". I had trouble to 
get a stable DMA support on the P1020.

>
> On Mon, Jul 25, 2016 at 8:48 AM, Sebastian Huber 
> <sebastian.huber at embedded-brains.de 
> <mailto:sebastian.huber at embedded-brains.de>> wrote:
>
>     Hello Nickolay,
>
>     the sources must have a proper license header. Is there a
>     particular reason why you didn't use the standard SDHC driver:
>
>     https://git.rtems.org/rtems-libbsd/tree/freebsd/sys/dev/sdhci/sdhci.c
>
>     It depends a bit on your QorIQ variant, some have nasty silicon
>     bugs in the SDHC area.
>
>     Please don't use rtems_disk_create_phys() for new code, use
>     rtems_blkdev_create() instead.
>
>     On 25/07/16 03:47, Nickolay Semyonov wrote:
>
>         From: Nickolay Semyonov <snob at wolpike.com
>         <mailto:snob at wolpike.com>>
>
>         Heavily tested with iozone.
>
>
>     -- 
>     Sebastian Huber, embedded brains GmbH
>
>     Address : Dornierstr. 4, D-82178 Puchheim, Germany
>     Phone   : +49 89 189 47 41-16
>     Fax     : +49 89 189 47 41-09
>     E-Mail  : sebastian.huber at embedded-brains.de
>     <mailto:sebastian.huber at embedded-brains.de>
>     PGP     : Public key available on request.
>
>     Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>
>

-- 
Sebastian Huber, embedded brains GmbH

Address : Dornierstr. 4, D-82178 Puchheim, Germany
Phone   : +49 89 189 47 41-16
Fax     : +49 89 189 47 41-09
E-Mail  : sebastian.huber at embedded-brains.de
PGP     : Public key available on request.

Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.