> -----Original Message----- > From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] > Sent: Friday, June 1, 2018 2:38 PM > To: Y.b. Lu <yangbo.lu@xxxxxxx> > Cc: Yinbo Zhu <yinbo.zhu@xxxxxxx>; Adrian Hunter > <adrian.hunter@xxxxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx; Xiaobo Xie > <xiaobo.xie@xxxxxxx> > Subject: Re: [PATCH v2] mmc: sdhci-of-esdhc: modify the sd clock in > soc_device_match way > > On 1 June 2018 at 08:31, Y.b. Lu <yangbo.lu@xxxxxxx> wrote: > >> -----Original Message----- > >> From: Yinbo Zhu > >> Sent: Monday, May 28, 2018 5:58 PM > >> To: Adrian Hunter <adrian.hunter@xxxxxxxxx>; Y.b. Lu > >> <yangbo.lu@xxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx > >> Cc: Xiaobo Xie <xiaobo.xie@xxxxxxx> > >> Subject: RE: [PATCH v2] mmc: sdhci-of-esdhc: modify the sd clock in > >> soc_device_match way > >> > >> > >> > >> -----Original Message----- > >> From: Adrian Hunter [mailto:adrian.hunter@xxxxxxxxx] > >> Sent: 2018年5月24日 16:58 > >> To: Yinbo Zhu <yinbo.zhu@xxxxxxx>; Y.b. Lu <yangbo.lu@xxxxxxx>; > >> linux-mmc@xxxxxxxxxxxxxxx > >> Cc: Xiaobo Xie <xiaobo.xie@xxxxxxx> > >> Subject: Re: [PATCH v2] mmc: sdhci-of-esdhc: modify the sd clock in > >> soc_device_match way > >> > >> On 22/05/18 15:06, Yinbo Zhu wrote: > > [...] > >> > + switch (host->mmc->ios.timing) { > >> > + case MMC_TIMING_LEGACY: > >> > + fixup = esdhc->clk_fixup->ds; > >> > + clock = esdhc_clock_fixup(clock, FULL_SPEED_MAX_DTR, > fixup); > >> > + fixup = esdhc->clk_fixup->mmc_ds; > >> > + clock = esdhc_clock_fixup(clock, MMC_HIGH_26_MAX_DTR, > fixup); > >> > + break; > >> > + case MMC_TIMING_SD_HS: > >> > + fixup = esdhc->clk_fixup->hs; > >> > + clock = esdhc_clock_fixup(clock, HIGH_SPEED_MAX_DTR, > fixup); > >> > + break; > >> > + case MMC_TIMING_MMC_HS: > >> > + fixup = esdhc->clk_fixup->mmc_hs; > >> > + clock = esdhc_clock_fixup(clock, MMC_HIGH_52_MAX_DTR, > fixup); > >> > + break; > >> > + case MMC_TIMING_UHS_SDR104: > >> > + fixup = esdhc->clk_fixup->sdr104; > >> > + clock = esdhc_clock_fixup(clock, UHS_SDR104_MAX_DTR, > fixup); > >> > + break; > >> > + case MMC_TIMING_MMC_HS200: > >> > + fixup = esdhc->clk_fixup->hs200; > >> > + clock = esdhc_clock_fixup(clock, MMC_HS200_MAX_DTR, > fixup); > >> > + break; > >> > + default: > >> > + break; > >> > >> >This logic looks fragile. I would expect to see something that > >> >looks more > >> like: > >> > >> > max_clk = esdhc->clk_fixup[host->mmc->ios.timing]; > >> > if (max_clk && clock > max_clk) > >> > clock = max_CLK; > >> Hi Adrian Hunter, > >> > >> Thanks your advice, your way will make code logic more clearly, but > >> MMC default max clock is 26MHz, SD default max clock is 25MHz, they > >> all use the same ios.timing in public code, If use array, There will > >> be a conflict, Do you have any good ways to resolve the conflict. > >> Thanks. > >> > >> Regards, > >> Yinbo > >> > > > > [Y.b. Lu] The MMC core driver used the timing MMC_TIMING_LEGACY for > both MMC and SD/SDIO at card initialization. > > However, the timing was different between MMC and SD/SDIO at > initialization. MMC was at legacy speed mode (up to 26MHz) while SD/SDIO > was at default speed mode (up to 25MHz). > > Actually I think we should define MMC_TIMING_MMC_LEGACY and > MMC_TIMING_SD_DEFAULT for MMC and SD/SDIO initializing timing. > > And use the right timing at the beginning in mmc_attach_sd/sdio/mmc(). > > Any suggestion? Adrian and Uffe :) > > I am fine with that. However, you need to make sure all host drivers can cope > with changing this. > > Perhaps, it's also sufficient to introduce MMC_TIMING_DEFAULT (used for SD) > and keep MMC_TIMING_LEGACY (for MMC). [Y.b. Lu] Great. It's safe to just introduce MMC_TIMING_DEFAULT. Thanks. > > > > > #define MMC_TIMING_LEGACY 0 > > #define MMC_TIMING_MMC_LEGACY 1 > > #define MMC_TIMING_SD_DEFAULT 2 > > #define MMC_TIMING_MMC_HS 3 > > #define MMC_TIMING_SD_HS 4 > > #define MMC_TIMING_UHS_SDR12 5 > > #define MMC_TIMING_UHS_SDR25 6 > > #define MMC_TIMING_UHS_SDR50 7 > > #define MMC_TIMING_UHS_SDR104 8 > > #define MMC_TIMING_UHS_DDR50 9 > > #define MMC_TIMING_MMC_DDR52 10 > > #define MMC_TIMING_MMC_HS200 11 > > #define MMC_TIMING_MMC_HS400 12 > > > > Kind regards > Uffe ��.n��������+%������w��{.n�����{��i��)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
