On 03/01/24 10:03:38, Adrian Hunter wrote: > Thanks for doing that! That seems to explain the mystery. > > You could hack the test to get an idea of how many successful > iterations there are before getting an error. > > For SDHCI, one difference between tuning and re-tuning is the > setting of bit-7 "Sampling Clock Select" of "Host Control 2 Register". > It is initially 0 and then set to 1 after the successful tuning. > Essentially, leaving it set to 1 is meant to speed up the re-tuning. > You could try setting it to zero instead, and see if that helps. > e.g. > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index c79f73459915..714d8cc39709 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -2732,6 +2732,7 @@ void sdhci_start_tuning(struct sdhci_host *host) > ctrl |= SDHCI_CTRL_EXEC_TUNING; > if (host->quirks2 & SDHCI_QUIRK2_TUNING_WORK_AROUND) > ctrl |= SDHCI_CTRL_TUNED_CLK; > + ctrl &= ~SDHCI_CTRL_TUNED_CLK; > sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); > > /* > Yes with that change, the re-tuning reliability test does pass. root@uz3cg-dwg-sec:/sys/kernel/debug/mmc0# echo 52 > /sys/kernel/debug/mmc0/mmc0\:0001/test [ 237.833585] mmc0: Starting tests of card mmc0:0001... [ 237.838759] mmc0: Test case 52. Re-tuning reliability... [ 267.845403] mmc0: Result: OK [ 267.848365] mmc0: Tests completed. Unfortunately I still see the error when looping on RPMB reads. For instance with this test script $ while true; do rpmb_read m4hash; usleep 300; done I can see the error triggering on the serial port after a minute or so. [ 151.682907] sdhci-arasan ff160000.mmc: __mmc_blk_ioctl_cmd: data error -84 Causing OP-TEE to panic since the RPMB read returns an error E/TC:? 0 E/TC:? 0 TA panicked with code 0xffff0000 E/LD: Status of TA 22250a54-0bf1-48fe-8002-7b20f1c9c9b1 E/LD: arch: aarch64 [...] if anything else springs to your mind I am happy to test of course - there are so many tunnables in this subsystem that experience is this area has exponential value (and I dont have much). Would it make sense if re-tuning requests are rejected unless a minimum number of jiffies have passed? should I try that as a change? or maybe delay a bit longer the RPMB access after a retune request?
