On 20 November 2017 at 05:50, Park Huijin <bbang.huijin.park@xxxxxxxxx> wrote: > 2017-11-15 18:13 GMT+09:00 Ulf Hansson <ulf.hansson@xxxxxxxxxx>: >> >> On 14 November 2017 at 03:48, Huijin Park <huijin.park@xxxxxxxxxxx> wrote: >> > Some eMMC products keep busy time a little longer intermittently. >> > (eg. prepare free blocks, garbage collection...) >> > In this case, we recommend to wait a little longer than fail. >> >> Is this an rpmb specific problem, because the code seems only to change that. >> >> Is it write and read or only write? > Yes. It's rpmb specific problem. > RPMB R/W use same flow. but only 'write' case makes the problem(long > busy state) sometimes. > When I test it, the 5~25ms is not enough although there is not max > busy time in the spec. As a matter of fact this isn't specific to RPMB writes at all but to all data writes. That's why we call card_busy_detect() after a data write. > >> >> > >> > Signed-off-by: Huijin Park <huijin.park@xxxxxxxxxxx> >> > --- >> > drivers/mmc/core/block.c | 2 +- >> > 1 file changed, 1 insertion(+), 1 deletion(-) >> > >> > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >> > index ea80ff4..b5b0fe6 100644 >> > --- a/drivers/mmc/core/block.c >> > +++ b/drivers/mmc/core/block.c >> > @@ -584,7 +584,7 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, >> > * Ensure RPMB command has completed by polling CMD13 >> > * "Send Status". >> > */ >> > - err = ioctl_rpmb_card_status_poll(card, &status, 5); >> > + err = ioctl_rpmb_card_status_poll(card, &status, 50); >> >> First, you are changing "re-tries" not a timeout value, which would >> seem like a better approach. > I will modify it. Thanks. > >> >> Second, it seems like we should remove the >> ioctl_rpmb_card_status_poll() function altogether and instead make use >> of the more generic card_busy_detect() function here. >> >> Then if card_busy_detect() needs to be adopted to suite rpmb, then we >> should do that instead. > I agree that. But the two function are different a little. > 'ioctl_rpmb_card_status_poll()' has interval(1~5ms) that prevent to > poll too frequently. Well, polling too frequently is then already a problem for the general data writes. Isn't it? Or you think RPMB may differ a bit in this regards? > So I suggest to improve 'card_busy_detect()' about interval time in > another patch. Okay. However, I don't think it's a stopper, you should be able to convert RPMB to use card_busy_detect() as is. Then you can fix the polling interval time on top. What you do need to fix is that card_busy_detect() takes an struct request *req as in-parameter, and uses it to print the disk_name. I suggest to change the in-parameter to be the disk_name instead, that way it would work for RPMB as well. > Then the 'ioctl_rpmb_card_status_poll()' can replaced by 'card_busy_detect()' Great! [...] Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
