| Message ID | 20230531070049.11806-1-wsa+renesas@sang-engineering.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [RFC/RFT] mmc: renesas_sdhi: add delay between tuning cmds | expand |
On Wed, May 31, 2023 at 2:00 AM Wolfram Sang <wsa+renesas@sang-engineering.com> wrote: > > Some SD cards failed to tune SDR104 occasionally. Adding a delay between > tuning commands makes the cards work although it is not yet known why. > It seems to be host dependent, only a few need such a delay (I found AMD > SDHCI and Freescale eSDHC so far). 25us is not enough, 50us never failed > up to now, so let's double that value until we know what is going on. > Extra thank you to Adam for sending me a problematic SD card to test. > > Reported-by: Adam Ford <aford173@gmail.com> > Closes: https://lore.kernel.org/all/CAHCN7xK_fr_gREVsOzN=atcS08mwufr-=7q1JAN=CCyVk_k-dA@mail.gmail.com/ > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> > --- > > This is one of the patches which look simple but took quite a while to > come up with. Part of it was identifying the issue, part of it was > trying to understand the issue. But I am stuck now, so I need help: > > @Adam: could you kindly test this patch with your setup? First, we need > to make sure it helps your case as well. I am testing this on a 5.10 kernel based on the Renesas RZ linux kernel branch. The good news is that the card doesn't hang like it used to on the older 4.19 kernel, but it still does not enumerate to SDR104 speeds. [ 5.222863] mmc0: tuning execution failed: -5 [ 5.308026] mmc0: new high speed SDHC card at address 59b4 [ 5.314397] mmcblk0: mmc0:59b4 USD00 29.5 GiB [ 5.320745] mmcblk0: p1 p2 # cat /sys/kernel/debug/mmc0/ios clock: 50000000 Hz actual clock: 49999998 Hz vdd: 21 (3.3 ~ 3.4 V) bus mode: 2 (push-pull) chip select: 0 (don't care) power mode: 2 (on) bus width: 2 (4 bits) timing spec: 2 (sd high-speed) signal voltage: 0 (3.30 V) driver type: 0 (driver type B) On other platforms, this same card registers 200MHz at SDR104 speeds. I'll try again on the latest 6.4 RC branch to see if there is some progress there. adam > > @Shimoda: If it helps for Adam's case, maybe we could ask the HW team if > they see a reason for this delay? I already scanned the SD/MMC/SDHI specs > without finding any trace, Marek helped as well. My gut feeling says it > is host controller specific. But first, let's hope it works for Adam. > > drivers/mmc/host/renesas_sdhi_core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c > index 345934e4f59e..6088cf94e1d3 100644 > --- a/drivers/mmc/host/renesas_sdhi_core.c > +++ b/drivers/mmc/host/renesas_sdhi_core.c > @@ -711,6 +711,9 @@ static int renesas_sdhi_execute_tuning(struct mmc_host *mmc, u32 opcode) > > if (cmd_error) > mmc_send_abort_tuning(mmc, opcode); > + > + /* FIXME: Needed for some SD cards. The reason is not known yet */ > + usleep_range(100, 250); > } > > ret = renesas_sdhi_select_tuning(host); > -- > 2.30.2 >
> I am testing this on a 5.10 kernel based on the Renesas RZ linux > kernel branch. The good news is that the card doesn't hang like it > used to on the older 4.19 kernel, but it still does not enumerate to > SDR104 speeds. U-Boot has a 1ms delay. Could you increase the delay to 1ms, please?
On Wed, May 31, 2023 at 12:45 PM Wolfram Sang <wsa+renesas@sang-engineering.com> wrote: > > > > I am testing this on a 5.10 kernel based on the Renesas RZ linux > > kernel branch. The good news is that the card doesn't hang like it > > used to on the older 4.19 kernel, but it still does not enumerate to > > SDR104 speeds. > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? Sorry for the delay, but I increased this to usleep_range(1000, 2500) and it still hangs. I don't know if the issue is dependent on the variant. For what it's worth, I am testing an RZ/G2M, but I can do the same thing on an RZ/G2N or RZ/G2H if you want. adam >
Hi Adam, > -----Original Message----- > From: Adam Ford <aford173@gmail.com> > Sent: Friday, June 16, 2023 3:35 PM > To: Wolfram Sang <wsa+renesas@sang-engineering.com>; Adam Ford > <aford173@gmail.com>; linux-mmc@vger.kernel.org; linux-renesas- > soc@vger.kernel.org; Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > Subject: Re: [RFC/RFT PATCH] mmc: renesas_sdhi: add delay between tuning > cmds > > On Wed, May 31, 2023 at 12:45 PM Wolfram Sang <wsa+renesas@sang- > engineering.com> wrote: > > > > > > > I am testing this on a 5.10 kernel based on the Renesas RZ linux > > > kernel branch. The good news is that the card doesn't hang like it > > > used to on the older 4.19 kernel, but it still does not enumerate to > > > SDR104 speeds. > > > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? > > Sorry for the delay, but I increased this to usleep_range(1000, 2500) and > it still hangs. > > I don't know if the issue is dependent on the variant. For what it's > worth, I am testing an RZ/G2M, but I can do the same thing on an RZ/G2N or > RZ/G2H if you want. I am doing 6.1.y testing[1] with all RZ board variants, [1] https://git.kernel.org/pub/scm/linux/kernel/git/cip/linux-cip.git/log/?h=linux-6.1.y-cip I have done SDHI testing with RZ/G2M 1.3 HiHope board and I didn't face this issue. Can you please let me know how to reproduce this issue? Cheers, Biju
On Fri, Jun 16, 2023 at 9:39 AM Biju Das <biju.das.jz@bp.renesas.com> wrote: > > Hi Adam, > > > -----Original Message----- > > From: Adam Ford <aford173@gmail.com> > > Sent: Friday, June 16, 2023 3:35 PM > > To: Wolfram Sang <wsa+renesas@sang-engineering.com>; Adam Ford > > <aford173@gmail.com>; linux-mmc@vger.kernel.org; linux-renesas- > > soc@vger.kernel.org; Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > > Subject: Re: [RFC/RFT PATCH] mmc: renesas_sdhi: add delay between tuning > > cmds > > > > On Wed, May 31, 2023 at 12:45 PM Wolfram Sang <wsa+renesas@sang- > > engineering.com> wrote: > > > > > > > > > > I am testing this on a 5.10 kernel based on the Renesas RZ linux > > > > kernel branch. The good news is that the card doesn't hang like it > > > > used to on the older 4.19 kernel, but it still does not enumerate to > > > > SDR104 speeds. > > > > > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? > > > > Sorry for the delay, but I increased this to usleep_range(1000, 2500) and > > it still hangs. > > > > I don't know if the issue is dependent on the variant. For what it's > > worth, I am testing an RZ/G2M, but I can do the same thing on an RZ/G2N or > > RZ/G2H if you want. > > I am doing 6.1.y testing[1] with all RZ board variants, > [1] https://git.kernel.org/pub/scm/linux/kernel/git/cip/linux-cip.git/log/?h=linux-6.1.y-cip > > I have done SDHI testing with RZ/G2M 1.3 HiHope board and I didn't face this issue. > > Can you please let me know how to reproduce this issue? It's not easy to reproduce, and it only happens on a small subset of cards. I sent one to Wolfram sometime last year. I can also take these same cards that hang when booting Linux, and they enumerate just fine in U-Boot at SRD104 speeds. I can use the same RZ/G2 board with other cards, and other cards work fine. I then tested these same 'failing' cards on other platforms and they work fine, so it seems like there is a tuning combination in Linux that is different from U-Boot that is unique to these certain cards which prevents them from working. adam > > Cheers, > Biju
Hi Adam, > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? > > Sorry for the delay, but I increased this to usleep_range(1000, 2500) > and it still hangs. Sigh, back to the drawing board... But still thanks for trying! I'll try to come up with something better after EOSS in Prague (will you be there by any chance?) Happy hacking, Wolfram
On Mon, Jun 19, 2023 at 1:02 AM Wolfram Sang <wsa+renesas@sang-engineering.com> wrote: > > Hi Adam, > > > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? > > > > Sorry for the delay, but I increased this to usleep_range(1000, 2500) > > and it still hangs. > > Sigh, back to the drawing board... But still thanks for trying! I'll try > to come up with something better after EOSS in Prague (will you be there > by any chance?) I really tried to go, but my employer declined this time. I was going to go on my own, butI didn't have enough personal time off available to fly out there. adam > > Happy hacking, > > Wolfram >
On Mon, Jun 19, 2023 at 5:39 AM Adam Ford <aford173@gmail.com> wrote: > > On Mon, Jun 19, 2023 at 1:02 AM Wolfram Sang > <wsa+renesas@sang-engineering.com> wrote: > > > > Hi Adam, > > > > > > U-Boot has a 1ms delay. Could you increase the delay to 1ms, please? > > > > > > Sorry for the delay, but I increased this to usleep_range(1000, 2500) > > > and it still hangs. > > > > Sigh, back to the drawing board... But still thanks for trying! I'll try > > to come up with something better after EOSS in Prague (will you be there > > by any chance?) Wolfram, I wanted to test the 6.7-rc1 on the microSD cards to see if there has been any improvement. In the process, I found yet another card which appears to have a similar issue where U-Boot can initialize a microSD card in SDR104 mode, but Linux fails. I think this brings the total to 3 cards. These same cards work on other platforms, so I don't think there is anything wrong with the cards, especially since they work on this platform in U-Boot. I added some debug code to indicate when when the priv->taps and priv->smpcmp bits are set when executing the timing command. FWICT, the priv-taps never get set, and smpcmp appears to always be successful. [ 3.741462] priv->smpcmp set bit 0 [ 3.747404] mmc_send_tuning opcode 19 [ 3.751173] priv->smpcmp set bit 1 [ 3.757129] mmc_send_tuning opcode 19 [ 3.760860] priv->smpcmp set bit 2 [ 3.766815] mmc_send_tuning opcode 19 [ 3.770564] priv->smpcmp set bit 3 [ 3.776514] mmc_send_tuning opcode 19 [ 3.780262] priv->smpcmp set bit 4 [ 3.786213] mmc_send_tuning opcode 19 [ 3.789966] priv->smpcmp set bit 5 [ 3.795915] mmc_send_tuning opcode 19 [ 3.799662] priv->smpcmp set bit 6 [ 3.805611] mmc_send_tuning opcode 19 [ 3.809364] priv->smpcmp set bit 7 [ 3.815294] mmc_send_tuning opcode 19 [ 3.819040] priv->smpcmp set bit 8 [ 3.824988] mmc_send_tuning opcode 19 [ 3.828735] priv->smpcmp set bit 9 [ 3.834685] mmc_send_tuning opcode 19 [ 3.838432] priv->smpcmp set bit 10 [ 3.844466] mmc_send_tuning opcode 19 [ 3.848214] priv->smpcmp set bit 11 [ 3.854251] mmc_send_tuning opcode 19 [ 3.857997] priv->smpcmp set bit 12 [ 3.864032] mmc_send_tuning opcode 19 [ 3.867778] priv->smpcmp set bit 13 [ 3.873820] mmc_send_tuning opcode 19 [ 3.877566] priv->smpcmp set bit 14 [ 3.883582] mmc_send_tuning opcode 19 [ 3.887328] priv->smpcmp set bit 15 [ 3.893361] priv->tap_num = 8 [ 3.896332] taps_size = 16 [ 3.899059] tap_cnt = 0 [ 3.901518] min_tap_row = 3 [ 3.904312] renesas_sdhi_select_tuning failed [ 3.908732] mmc1: tuning execution failed: -5 When I compare the values of taps and smpcmp in U-Boot vs linux, I get U-Boot Shows: taps = dfdf priv->smpcmp = dfdf Sometimes, priv->smpcmp = df9f Linux shows: priv->taps = 0 priv->smpcmp = ffff And the Linux values are consistent. Another thing that is interesting to me is that U-Boot explicitly forces PIO when tuning and it only happens when executing "ret = mmc_send_tuning(mmc, opcode, NULL);" Is there a proper way to temporarily switch to PIO in the Linux driver to see if I can accomplish the same thing? If I eject the card before it's mounted, it waits for the card to be inserted. If I insert the card, it enumerates: [ 3.701926] renesas_sdhi_start_signal_voltage_switch: 0 [ 3.869834] renesas_sdhi_start_signal_voltage_switch: 1 [ 3.898030] mmc_send_tuning opcode 19 [ 3.907006] priv->taps set bit 0 [ 3.910232] priv->smpcmp set bit 0 [ 3.916160] mmc_send_tuning opcode 19 [ 3.919901] priv->taps set bit 1 [ 3.923142] priv->smpcmp set bit 1 [ 3.929054] mmc_send_tuning opcode 19 [ 3.932793] priv->taps set bit 2 [ 3.936034] priv->smpcmp set bit 2 [ 3.941953] mmc_send_tuning opcode 19 [ 3.945697] priv->taps set bit 3 [ 3.948938] priv->smpcmp set bit 3 [ 3.954857] mmc_send_tuning opcode 19 [ 3.958596] priv->taps set bit 4 [ 3.961836] priv->smpcmp set bit 4 [ 3.967756] mmc_send_tuning opcode 19 [ 3.974009] mmc_send_tuning opcode 19 [ 3.977749] priv->taps set bit 6 [ 3.980987] priv->smpcmp set bit 6 [ 3.986910] mmc_send_tuning opcode 19 [ 3.990636] priv->taps set bit 7 [ 3.993876] priv->smpcmp set bit 7 [ 3.999797] mmc_send_tuning opcode 19 [ 4.003535] priv->taps set bit 8 [ 4.006760] priv->smpcmp set bit 8 [ 4.012688] mmc_send_tuning opcode 19 [ 4.016427] priv->taps set bit 9 [ 4.019668] priv->smpcmp set bit 9 [ 4.025587] mmc_send_tuning opcode 19 [ 4.029326] priv->taps set bit 10 [ 4.032654] priv->smpcmp set bit 10 [ 4.038689] mmc_send_tuning opcode 19 [ 4.042422] priv->taps set bit 11 [ 4.045745] priv->smpcmp set bit 11 [ 4.051748] mmc_send_tuning opcode 19 [ 4.055484] priv->taps set bit 12 [ 4.058795] priv->smpcmp set bit 12 [ 4.064803] mmc_send_tuning opcode 19 [ 4.071044] mmc_send_tuning opcode 19 [ 4.074752] priv->taps set bit 14 [ 4.078075] priv->smpcmp set bit 14 [ 4.084077] mmc_send_tuning opcode 19 [ 4.087832] priv->taps set bit 15 [ 4.091157] priv->smpcmp set bit 15 [ 4.097152] priv->tap_num = 8 [ 4.100127] taps_size = 16 [ 4.102828] priv->taps = dfdf [ 4.105800] priv->smpcmp = dfdf [ 4.108947] tap_cnt = 7 [ 4.111395] min_tap_row = 3 [ 4.116003] mmc1: new ultra high speed SDR104 SDHC card at address 59b4 [ 4.123361] mmcblk1: mmc1:59b4 USD00 29.5 GiB [ 4.129577] mmcblk1: p1 p2 Is there some sort of reset or power-cycle that needs to be better configured? thanks, adam > > I really tried to go, but my employer declined this time. I was going > to go on my own, butI didn't have enough personal time off available > to fly out there. > > adam > > > > Happy hacking, > > > > Wolfram > >
diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c index 345934e4f59e..6088cf94e1d3 100644 --- a/drivers/mmc/host/renesas_sdhi_core.c +++ b/drivers/mmc/host/renesas_sdhi_core.c @@ -711,6 +711,9 @@ static int renesas_sdhi_execute_tuning(struct mmc_host *mmc, u32 opcode) if (cmd_error) mmc_send_abort_tuning(mmc, opcode); + + /* FIXME: Needed for some SD cards. The reason is not known yet */ + usleep_range(100, 250); } ret = renesas_sdhi_select_tuning(host);
Some SD cards failed to tune SDR104 occasionally. Adding a delay between tuning commands makes the cards work although it is not yet known why. It seems to be host dependent, only a few need such a delay (I found AMD SDHCI and Freescale eSDHC so far). 25us is not enough, 50us never failed up to now, so let's double that value until we know what is going on. Extra thank you to Adam for sending me a problematic SD card to test. Reported-by: Adam Ford <aford173@gmail.com> Closes: https://lore.kernel.org/all/CAHCN7xK_fr_gREVsOzN=atcS08mwufr-=7q1JAN=CCyVk_k-dA@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- This is one of the patches which look simple but took quite a while to come up with. Part of it was identifying the issue, part of it was trying to understand the issue. But I am stuck now, so I need help: @Adam: could you kindly test this patch with your setup? First, we need to make sure it helps your case as well. @Shimoda: If it helps for Adam's case, maybe we could ask the HW team if they see a reason for this delay? I already scanned the SD/MMC/SDHI specs without finding any trace, Marek helped as well. My gut feeling says it is host controller specific. But first, let's hope it works for Adam. drivers/mmc/host/renesas_sdhi_core.c | 3 +++ 1 file changed, 3 insertions(+)