Hi Wolfram,
On Tue, Sep 17, 2019 at 9:46 PM Wolfram Sang
<wsa+renesas@xxxxxxxxxxxxxxxxxxxx> wrote:
> PM has been reworked, so eMMC gets now detected on R-Car H3 ES1.0 and
> 2.0 as well as M3-N without the workaround. Card detect and write
> protect also still work. Remove the workaround.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> --- a/drivers/mmc/host/tmio_mmc_core.c
> +++ b/drivers/mmc/host/tmio_mmc_core.c
> @@ -1208,15 +1208,6 @@ int tmio_mmc_host_probe(struct tmio_mmc_host *_host)
> if (!_host->reset)
> _host->reset = tmio_mmc_reset;
>
> - /*
> - * On Gen2+, eMMC with NONREMOVABLE currently fails because native
> - * hotplug gets disabled. It seems RuntimePM related yet we need further
> - * research. Since we are planning a PM overhaul anyway, let's enforce
> - * for now the device being active by enabling native hotplug always.
> - */
> - if (pdata->flags & TMIO_MMC_MIN_RCAR2)
> - _host->native_hotplug = true;
> -
> /*
> * While using internal tmio hardware logic for card detection, we need
> * to ensure it stays powered for it to work.
On Salvator-XS with R-Car M3-N, this causes lock ups during early userspace
boot up (Debian 9 nfsroot), usually after:
[ OK ] Started D-Bus System Message Bus.
At first I suspected systemd. Then I noticed the kernel had locked up
completely, and no longer responded to ping requests.
Interestingly, this patch has been part of renesas-drivers since the
2019-10-15-v5.4-rc3 release, without real issues.
The first time I saw the issue was last week. Then it happened only after I
had disabled a debug print, which probably caused a timing difference in
Runtime PM disablement (and was fully reproducible).
Today, it was fairly reproducible, so I managed to bisect it to commit
7a7dab237027939c ("mmc: tmio: remove workaround for NON_REMOVABLE") in
mmc/next. Reverting this commit fixes the issue.
The issue can also be fixed by:
1. enabling the hs400_4taps and/or hs400_disabled quirks in
sdhi_quirks_match[], OR
2. forcing use_4tap = true in renesas_sdhi_check_scc_error().
Salvator-X(S) with R-Car H3 ES1.0 & ES2.0, or M3-W ES1.0, the issue
does not show up (probably because of sdhi_quirks_match[]).
Do you have a clue?
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
