Hi Ulf,
On 18:50 Tue 22 Oct , Ulf Hansson wrote:
> > And this is after the patch has been applied:
> > KB reclen write rewrite read reread
> > 51200 4 251 990 3280 3244
> > 51200 8 460 1545 4460 4463
> > 51200 16 878 2633 7023 7028
> > 51200 32 1380 4394 9802 9832
> > 51200 64 2457 6216 12314 12314
> > 51200 128 3667 7894 14087 14088
> > 51200 256 6422 5916 15085 15086
> > 51200 512 5536 10994 12571 15659
> > 51200 1024 9112 9499 16203 16205
> > 51200 2048 10197 10502 16363 16368
> > 51200 4096 10524 10238 8850 16309
> > 51200 8192 9615 10456 16528 16529
> > 51200 16384 10553 10428 16803 16803
>
> Hi Oskar,
>
> The numbers were not that impressing from the beginning, so that could
> be why you don't see any impact.
> What kind of card are you using, eMMC/SD? In what speed mode are the
> card operating in?
The test was run on an Beagleboard with sdcard. I will try to find another
board with
eMMC support and rerun the tests.
> >> > + /*
> >> > + * Try to get card status which indicates the card state after
> >> > + * command execution. If the first attempt fails, we can't be
> >> > + * sure the returned status is for the r/w command.
> >> > + */
> >> > + for (retries = 2; retries >= 0; retries--) {
> >> > + err = get_card_status(card, &status, 0);
> >> > + if (!err)
> >> > + break;
> >> > +
> >> > + status_valid = false;
> >> > + pr_err("%s: error %d sending status command, %sing\n",
> >> > + req->rq_disk->disk_name, err,
> >> > + retries ? "retry" : "abort");
> >> > + }
> >>
> >> Do we have to issue a CMD13 (get_card_status), even if we are using
> >> the open-ended transmission sequence? In other words, could we make
> >> use of the response from CMD12 (stop transmission) instead?
> >
> > That's probably a good idea. Do you know of a way to check if CMD12 has been
> > sent or not?
>
> Have a look for "mmc_host_cmd23", which gets translated into
> "MMC_BLK_CMD23" for the mmc block layer. This will give you some hints
> of were to look.
Thanks! We will revise the patch according to your comments.
-Oskar
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