Re: [PATCH V2 0/2] mmc: sdhci-sprd: Add SD HS mode online tuning

From: Wenchao Chen
Date: Tue Aug 15 2023 - 06:56:15 EST


On Tue, Aug 15, 2023 at 6:37 PM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 15/08/23 13:29, Wenchao Chen wrote:
> > On Tue, Aug 15, 2023 at 2:21 PM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> >>
> >> On 15/08/23 04:40, Wenchao Chen wrote:
> >>> Change in v2:
> >>> - add mmc_sd_switch() and mmc_send_status() to the header file
> >>> - split up core changes from host driver changes
> >>> - Use pr_debug instead of dev_info and dev_dbg
> >>> - Optimize the best sampled value algorithm
> >>
> >> What about hooking ->set_ios() as Ulf suggested?
> >>
> >
> > I've tried that, but it's not a good way to do it.
> > We found that sdhci_runtime_resume_host() calls ->set_ios, but we
> > don't want to do that.
>
> Given that sdhci_sprd_runtime_resume() calls sdhci_runtime_resume_host(),
> it should be possible to determine when to tune, right?
>

You mean like this? For example:
static int sdhci_sprd_runtime_resume(struct device *dev)
{
...
sprd_host->need_hs_tuning = false;
sdhci_runtime_resume_host(host, 1);
sprd_host->need_hs_tuning = true;
...
}

> > We just need SD HS mode tuning at mmc_sd_init_card().
> >
> >>>
> >>> Wenchao Chen (2):
> >>> mmc: core: Add host specific tuning support for SD HS mode
> >>> mmc: sdhci-sprd: Add SD HS mode online tuning
> >>>
> >>> drivers/mmc/core/sd.c | 12 +++
> >>> drivers/mmc/core/sd_ops.c | 1 +
> >>> drivers/mmc/host/sdhci-sprd.c | 152 ++++++++++++++++++++++++++++++++++
> >>> include/linux/mmc/host.h | 8 ++
> >>> 4 files changed, 173 insertions(+)
> >>>
> >>
>