Addy, On Tue, Dec 2, 2014 at 7:16 PM, Addy Ke <addy.ke@xxxxxxxxxxxxxx> wrote: > This patch add a new quirk to add a s/w timer to notify the driver > to terminate current transfer and report a data timeout to the core, > if DTO interrupt does NOT come within the given time. > > dw_mmc call mmc_request_done func to finish transfer depends on > DTO interrupt. If DTO interrupt does not come in sending data state, > the current transfer will be blocked. > > But this case really exists, when driver reads tuning data from > card on RK3288-pink2 board. I measured waveforms by oscilloscope > and found that card clock was always on and data lines were always > holded high level in sending data state. > > We got the reply from synopsys: > There are two counters but both use the same value of [31:8] bits. > Data timeout counter doesn't wait for stop clock and you should get > DRTO even when the clock is not stopped. > Host Starvation timeout counter is triggered with stop clock condition. > > This means that host should get DRTO and DTO interrupt. > > But we really don't get any data-related interrupt in RK3X SoCs. > And driver can't get data transfer state, it can do nothing but wait for. > > We don't know why we have this problem, but we need it to fix this problem now. > And I will post a follow up change when we find the root cause. > > Signed-off-by: Addy Ke <addy.ke@xxxxxxxxxxxxxx> > --- > Changes in v2: > - fix some typo. > - remove extra timeout value (250ms). > - remove dw_mci_dto_start_monitor func. > - use "broken-dto" for new quirk and change Subject for it. > > Changes in v3: > - Remove dts for broken-dto, just add this quirk in dw_mci_rockchip_init > > drivers/mmc/host/dw_mmc-rockchip.c | 3 +++ > drivers/mmc/host/dw_mmc.c | 41 +++++++++++++++++++++++++++++++++++++- > include/linux/mmc/dw_mmc.h | 5 +++++ > 3 files changed, 48 insertions(+), 1 deletion(-) This seems reasonable to me. I do hope that you can get to a root cause, but I don't think this is a terrible bit of code to carry. Obviously it's up to the folks who maintain dw_mmc and the mmc subsystem, but: Reviewed-by: Doug Anderson <dianders@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
