On 03/05/2014 06:21 PM, Lukasz Majewski wrote: > Hi Beomho, > >> This patch set for use dw mmc controller. >> First, add dw mmc controller initialization. >> And then, change exynos4 mmc gpio configuration. >> Additionally, I have removed exynos4x12_set_mmc_clk function. >> Because samsung_get_base_clock() (exynos4x12/ exynos4) return same >> value. > > Thank you for supporting the DW_MMC on Trats2. > > I've got following comments: > > 1. Piotr Wilczek (added to CC) is moving the Trats/Trats2 board to > support configuration via device tree. From device tree it is easier to > seamlessly enable support for DW_MMC (SDMMC4 controller) - at least we > would avoid adding new #ifdefs. The way to enable it is almost > identical to Exynos5250 (board "snow"). > > Now the v4 has been sent, so please look (and probably rebase your work) > on them: > > "[PATCH V4 00/12] Exynos4: add support for device tree" > http://article.gmane.org/gmane.comp.boot-loaders.u-boot/181576/match=exynos4+add+support+device+tree Ok. It will be change to use the dt file.
> > > 2. We did some rough tests for the DW_MMC implementation on Trats2 (with > clock phase settings similar to the one in the kernel) and it turned > out that SDHCI is faster. > > Two possible explanations: > - DDR is not supported by memory embedded on Trats2 > - We did something wrong, so as a result the DDR mode for > DW_MMC/eMMC memory was not working properly. DDR mode didn't implement at u-boot. It need to update code for DDR mode. If you want to use DDR mode, then i will implement it. > > However, I still believe, that DW_MMC with properly enabled DDR could > outperform SDHCI. Right, If DW-mmc is used with DDR mode, then it's more better than SDHCI. there is no reason that we didn't use the dw-mmc controller at trats2 board. > > Why this speedup is important? > > We struggle to reduce time needed for flashing large images (like > rootfs - e.g. 400 MiB in size). > > Any help is more than welcome :-). > > > 3. u-boot general advice: > > When you alter things related to a particular board (like > trats2 in this case) it is welcome to add the board's maintainer to CC. > You can find them at boards.cfg. Maybe, need to add Samsung-SoC maintainer, and base on SoC repository. Best Regards, Jaehoon Chung > >> >> This patch set is tested on Trats2 board. >> >> Beomho Seo (3): >> board: samsung: trats2: Add DW MMC controller initialization >> arm: exynos: pinmux: Add sdmmc4 gpio confifuration >> arm: exynos: clock: Remove exynos4x12_set_mmc_clk function >> >> arch/arm/cpu/armv7/exynos/clock.c | 29 >> +---------------------------- arch/arm/cpu/armv7/exynos/pinmux.c | >> 20 +++++++++++++++----- board/samsung/trats2/trats2.c | 31 >> +++++++++++++++++++++---------- 3 files changed, 37 insertions(+), 43 >> deletions(-) > > > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
