Re: [RESEND PATCHv1 7/8] mmc: sdhci-msm: Make HS400 tuning follow as per recommeneded HW sequence

Adrian Hunter
2017-01-19T10:24:21Z

On 10/01/17 09:00, Ritesh Harjani wrote:
> During tuning execution for HS400 mode, HW sequence recommends
> to select MCLK_SEL/2(0x3) in VENDOR_SPEC & sdhc msm clock at GCC
> to be 400MHZ (nearest supported clk). Add this change in tuning
> sequence during HS400 tuning.
>
> Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>

You may need to re-base this if you make changes as per patch 6, but otherwise:

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
> drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 84d29dd..fa9bce3 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -151,7 +151,8 @@ static unsigned int msm_get_clock_rate_for_bus_mode(struct sdhci_host *host,
> */
> if (ios.timing == MMC_TIMING_UHS_DDR50 ||
> ios.timing == MMC_TIMING_MMC_DDR52 ||
> - ios.timing == MMC_TIMING_MMC_HS400)
> + ios.timing == MMC_TIMING_MMC_HS400 ||
> + host->flags & SDHCI_HS400_TUNING)
> clock *= 2;
> return clock;
> }
> @@ -611,7 +612,8 @@ void sdhci_msm_hc_select_mode(struct sdhci_host *host)
> {
> struct mmc_ios ios = host->mmc->ios;
>
> - if (ios.timing == MMC_TIMING_MMC_HS400)
> + if (ios.timing == MMC_TIMING_MMC_HS400 ||
> + host->flags & SDHCI_HS400_TUNING)
> msm_hc_select_hs400(host);
> else
> msm_hc_select_default(host);
> @@ -831,6 +833,16 @@ static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
> ios.timing == MMC_TIMING_UHS_SDR104))
> return 0;
>
> + /*
> + * For HS400 tuning in HS200 timing requires:
> + * - select MCLK/2 in VENDOR_SPEC
> + * - program MCLK to 400MHz (or nearest supported) in GCC
> + */
> + if (host->flags & SDHCI_HS400_TUNING) {
> + sdhci_msm_hc_select_mode(host);
> + msm_set_clock_rate_for_bus_mode(host, ios.clock);
> + }
> +
> retry:
> /* First of all reset the tuning block */
> rc = msm_init_cm_dll(host);
>