Re: [PATCH] mmc: host: dw-mmc-rockchip: avoid logspam when cd-broken

From: Peter Geis
Date: Tue Mar 01 2022 - 06:49:38 EST


On Tue, Mar 1, 2022 at 6:23 AM Robin Murphy <robin.murphy@xxxxxxx> wrote:
>
> On 2022-02-28 22:36, Peter Geis wrote:
> > The dw_mmc-rockchip driver drops a large amound of logspam constantly
> > when the cd-broken flag is enabled.
> > Set the warning to be debug ratelimited in this case.
>
> Isn't this just papering over some fundamental problem with the clock?
> If it's failing to set the expected rate for communicating with a card,
> then presumably that's an issue for correct operation in general? The
> fact that polling for a card makes a lot more of that communication
> happen seems unrelated :/

Good Morning,

This only happens when a card is not inserted, so communication cannot happen.
I found it while lighting off the SoQuartz module.
As it is pin compatible with the RPi CM4, and the CM4 does not have a
card detect line, sdmmc is non functional without cd-broken.
This led to the fun spew when there wasn't a card inserted as this
function is called every poll tick.

Thanks,
Peter

>
> Robin.
>
> > Signed-off-by: Peter Geis <pgwipeout@xxxxxxxxx>
> > ---
> > drivers/mmc/host/dw_mmc-rockchip.c | 9 +++++++--
> > 1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
> > index 95d0ec0f5f3a..d0ebf0afa42a 100644
> > --- a/drivers/mmc/host/dw_mmc-rockchip.c
> > +++ b/drivers/mmc/host/dw_mmc-rockchip.c
> > @@ -50,8 +50,13 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
> > cclkin = ios->clock * RK3288_CLKGEN_DIV;
> >
> > ret = clk_set_rate(host->ciu_clk, cclkin);
> > - if (ret)
> > - dev_warn(host->dev, "failed to set rate %uHz\n", ios->clock);
> > + if (ret) {
> > + /* this screams when card detection is broken */
> > + if (host->slot->mmc->caps & MMC_CAP_NEEDS_POLL)
> > + dev_dbg_ratelimited(host->dev, "failed to set rate %uHz\n", ios->clock);
> > + else
> > + dev_warn(host->dev, "failed to set rate %uHz\n", ios->clock);
> > + }
> >
> > bus_hz = clk_get_rate(host->ciu_clk) / RK3288_CLKGEN_DIV;
> > if (bus_hz != host->bus_hz) {