Hi Sascha, Alexander, On Tue, Sep 13, 2016 at 09:06:04AM +0200, Sascha Hauer wrote: > On Mon, Sep 12, 2016 at 10:17:18AM +0200, Alexander Kurz wrote: > > On Mon, 12 Sep 2016, Sascha Hauer wrote: > > > On Fri, Sep 09, 2016 at 05:43:39PM +0200, Alexander Kurz wrote: > > > > Signed-off-by: Alexander Kurz <akurz@xxxxxxxx> > > > > --- > > > > Documentation/boards/imx.rst | 1 + > > > > arch/arm/mach-imx/include/mach/generic.h | 13 +++++++++++++ > > > > arch/arm/mach-imx/include/mach/imx_cpu_types.h | 1 + > > > > 3 files changed, 15 insertions(+) > > > > > > Seems to be straight forward to add i.MX50 support. I have nothing to > > > add, except: Applied, thanks > > > > > > Out of curiosity: What device do you use with i.MX50? Is it some E-Book > > > reader again? > > The imx50 has a build-in e-ink driver, so it is more or less a SOC > > tailored on e-books. It is used in some already outdated e-books like the > > 4th and 5th generation Kindles, some Kobos and Tolinos. > > The successor for the imx50 became the e-ink driver equiped variants > > of the imx6sl, which is used in most current generation e-book readers. > > > > While the current patchsets will enable barebox to run on different > > e-books e.g. when beeing booted via an installed bootloader, there is > > still an open issue: RAM initialization. > > Freescale used a "DRAMMC" which seems to be very unique to this SOC. > > Documentation on it is available in the Reference Manual, but it covers > > some details quite briefly. > > Related on barebox: > > it is not clear, whether DRAMMC initialization via imximg-DCD is possible > > at all. All existing bootloaders I have seen so far used some > > imximg-plugin code (which is currently not supported by barebox). > > A two-stage bootloader implementation via xload may be an alternative. > > Yes, that could work. How I understand it the plugin image is > responsible for initializing SDRAM and for loading the final image. > Then the job of the ROM is done anyway, so normally I do not see a > reason for plugin images. The only usecase seems to be HAB when the > final image is checked by the HAB code when returning to ROM. So, I found my Sandisk Connect WMD (Wireless Media Drive) and I also re-located the open source dump by Sandisk [1]. The first problem I need to solve is the DDR training code. The device shipped with U-boot, and the training code seems to be in flash_header.S [2]. There's a large number of lines preceded by comments of the form /* setmem /32 0x140000f8 = 0x00010101 */ which lends itself to a conversion into .imxcfg format. However, there's quite a bit of code that doesn't appear to be doing simple writes. Additionally, there's a lowlevel_init.S in the same directory. There is a linker script putting flash_header.o at the beginning of the binary image. Is it easier to just do that, bypassing imx-image? Or, is there a conversion utility my google fu isn't pulling up? thx, Jason. [1] https://github.com/SanDisk-Open-Source/wireless-media-drive [2] https://github.com/SanDisk-Open-Source/wireless-media-drive/blob/master/u-boot-2009.08/board/freescale/mx50_rdp/flash_header.S _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
