> -----Original Message----- > From: Adrian Hunter <adrian.hunter@xxxxxxxxx> > Sent: Tuesday, August 9, 2022 2:37 PM > To: Seunghui Lee <sh043.lee@xxxxxxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx > Cc: 'DooHyun Hwang' <dh0421.hwang@xxxxxxxxxxx> > Subject: Re: [PATCH] mmc: sd: Remove the patch that fix signal voltage > when there is no power cycle > > On 8/08/22 11:24, Seunghui Lee wrote: > >> -----Original Message----- > >> From: Adrian Hunter <adrian.hunter@xxxxxxxxx> > >> Sent: Tuesday, July 26, 2022 7:57 PM > >> To: Seunghui Lee <sh043.lee@xxxxxxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx; > >> adrian.hunter@xxxxxxxxx > >> Cc: 'DooHyun Hwang' <dh0421.hwang@xxxxxxxxxxx> > >> Subject: Re: [PATCH] mmc: sd: Remove the patch that fix signal > >> voltage when there is no power cycle > >> > >> On 26/07/22 05:56, Seunghui Lee wrote: > >>>> -----Original Message----- > >>>> From: Seunghui Lee <sh043.lee@xxxxxxxxxxx> > >>>> Sent: Thursday, July 21, 2022 2:59 PM > >>>> To: ulf.hansson@xxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; > >>>> adrian.hunter@xxxxxxxxx > >>>> Cc: Seunghui Lee <sh043.lee@xxxxxxxxxxx>; DooHyun Hwang > >>>> <dh0421.hwang@xxxxxxxxxxx> > >>>> Subject: [PATCH] mmc: sd: Remove the patch that fix signal voltage > >>>> when there is no power cycle > >>>> > >>>> At first, all error flow of mmc_set_uhs_voltage() has power cycle > >>>> except R1_ERROR and no start_signal_voltage_switch() func pointer. > >>>> > >>>> There is the performance regression issue of SDR104 SD card from > >>>> the market VOC. Normally, once a SDR104 SD card fails to switch > >>>> voltage, it works HS mode. > >>>> And then it initializes SDR104 mode after system resume or error > >> handling. > >>>> > >>>> However, with below patch, > >>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ > >>>> co > >>>> mmit/ > >>>> drivers/mmc/core/sd.c?id=6a11fc47f175c8d87018e89cb58e2d36c66534cb > >>>> Once a SD card does, it initializes SDR25 mode forever after system > >>>> resume or error handling(re-initialized). > >>>> Host updates sd3_bus_mode by calling mmc_read_switch(), the value > >>>> of sd3_bus_mode doesn't set for SDR104, SDR50 and DDR50 mode. > >>>> > >>>> So, if host doesn't update sd3_bus_mode, the SD card works SDR104 > >>>> mode after system resume or error-handling. > >>>> > >>>> Here is an example. > >>>> > >>>> AS-IS : test log > >>>> // normal case : sd3_bus_mode = 0x1F, sd_bus_speed = SDR104, clock > >> 208MHz > >>>> [ 111.907789] [1: kworker/1:3: 772] [TEST] mmc_sd_init_card: 1119: > >>>> caps=0x407f020f, sd3_bus_mode=0x1f, v18_fixup_failed false, > >>>> signal_voltage =0x1. > >>>> [ 111.907824] [1: kworker/1:3: 772] [TEST] mmc_sd_init_card: 1149: > >> rocr > >>>> 0xc1ff8000, S18A, uhs. > >>>> [ 111.908707] [1: kworker/1:3: 772] [TEST] > sd_update_bus_speed_mode: > >>>> caps 0x407f020f, sd3_bus_mode = 0x1f, sd_bus_speed = 3, card->ocr = > >>>> 0x40000. > >>>> [ 111.912484] [1: kworker/1:3: 772] [TEST] sd_set_bus_speed_mode: > >>>> sd_bus_speed=3, timing=6, uhs_max_dtr=208000000, card->ocr=0x40000. > >>>> // resume : issue occurs : SDcard doesn't release busy for checking > >>>> 10 times > >>>> [ 112.096550] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1040: > >>>> card->ocr 0x40000. > >>>> [ 112.096560] [5: kworker/5:2: 207] [TEST] mmc_sd_get_cid: ocr > >>>> 0x40000(pocr 0x40000), retries 10. > >>>> ... > >>>> [ 114.531129] [5: kworker/5:2: 207] [TEST] mmc_power_cycle. > >>>> [ 114.579500] [5: kworker/5:2: 207] [TEST] mmc_sd_get_cid: ocr > >>>> 0x41040000(pocr 0x40000), retries 0. > >>>> [ 114.579506] [5: kworker/5:2: 207] mmc0: Skipping voltage switch > >>>> [ 114.757575] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1119: > >>>> caps=0x407f020f, sd3_bus_mode=0x1f, v18_fixup_failed false, > >>>> signal_voltage =0x0. > >>>> [ 114.757583] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1128: > >>>> switch with oldcard. > >>>> [ 114.759742] [5: kworker/5:2: 207] [TEST] mmc_read_switch: > >> sd_switch > >>>> ret 0, sd3_bus_mode=3. > >>>> // sd3_bus_mode = 0x3 supports HS, SDR25 and SDR12 > >>>> [ 114.759750] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1157: > >>>> switch hs. > >>>> // next resume : the SDcard initializes to SDR25(HS) > >>>> mode(sd_bus_speed = 1) by sd3_bus_mode setting with clk 50MHz > >>>> [ 114.968346] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1040: > >>>> card->ocr 0x40000. > >>>> [ 114.968359] [5: kworker/5:2: 207] [TEST] mmc_sd_get_cid: ocr > >>>> 0x40000(pocr 0x40000), retries 10. > >>>> [ 115.167346] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1119: > >>>> caps=0x407f020f, sd3_bus_mode=0x3, v18_fixup_failed false, > >>>> signal_voltage =0x1. > >>>> [ 115.167366] [5: kworker/5:2: 207] [TEST] mmc_sd_init_card: 1149: > >> rocr > >>>> 0xc1ff8000, S18A, uhs. > >>>> [ 115.168041] [5: kworker/5:2: 207] [TEST] mmc_sd_init_uhs_card: > >> before > >>>> update: caps 0x407f020f, sd3_bus_mode = 3, sd_bus_speed = 3, > >>>> card->ocr = 0x40000. > >>>> [ 115.168051] [5: kworker/5:2: 207] [TEST] > sd_update_bus_speed_mode: > >>>> caps 0x407f020f, sd3_bus_mode = 3, sd_bus_speed = 1, card->ocr = > >> 0x40000. > >>>> [ 115.169176] [5: kworker/5:2: 207] [TEST] sd_set_bus_speed_mode: > >>>> sd_bus_speed=1, timing=4, uhs_max_dtr=50000000, card->ocr=0x40000. > >>>> > >>>> TO-BE : TEST log with this commit > >>>> // resume : issue occurs : SDcard doesn't release busy for checking > >>>> 10 times > >>>> [ 1843.594805] [4: kworker/4:5:21512] [TEST] mmc_sd_get_cid: ocr > >>>> 0x41040000(pocr 0x40000), retries 0. > >>>> [ 1843.594812] [4: kworker/4:5:21512] mmc0: Skipping voltage switch > >>>> [ 1843.772555] [4: kworker/4:5:21512] [TEST] mmc_sd_init_card: 1122: > >>>> caps=0x407f020f, sd3_bus_mode=0x1f, v18_fixup_failed false, > >>>> signal_voltage =0x0. > >>>> // no update sd3_bus_mode value > >>>> [ 1843.772563] [4: kworker/4:5:21512] [TEST] mmc_sd_init_card: 1164: > >>>> switch hs. > >>>> // next resume : the SDcard initializes to SDR104 > >>>> [ 1844.191295] [5: kworker/5:93: 2282] [TEST] mmc_sd_init_card: > 1122: > >>>> caps=0x407f020f, sd3_bus_mode=0x1f, v18_fixup_failed false, > >>>> signal_voltage =0x1. > >>>> [ 1844.191315] [5: kworker/5:93: 2282] [TEST] mmc_sd_init_card: > 1154: > >>>> rocr 0xc1ff8000, S18A, uhs. > >>>> [ 1844.192175] [5: kworker/5:93: 2282] [TEST] mmc_sd_init_uhs_card: > >>>> before update: caps 0x407f020f, sd3_bus_mode = 0x1f, sd_bus_speed = > >>>> 3, > >>>> card->ocr = 0x40000. > >>>> [ 1844.192187] [5: kworker/5:93: 2282] [TEST] > >> sd_update_bus_speed_mode: > >>>> caps 0x407f020f, sd3_bus_mode = 0x1f, sd_bus_speed = 3, card->ocr = > >>>> 0x40000. > >>>> [ 1844.198697] [5: kworker/5:93: 2282] [TEST] sd_set_bus_speed_mode: > >>>> sd_bus_speed=3, timing=6, uhs_max_dtr=208000000, card->ocr=0x40000. > >>>> > >>>> Signed-off-by: Seunghui Lee <sh043.lee@xxxxxxxxxxx> > >>>> Tested-by: DooHyun Hwang <dh0421.hwang@xxxxxxxxxxx> > >>>> --- > >>>> drivers/mmc/core/sd.c | 47 > >>>> ++----------------------------------------- > >>>> 1 file changed, 2 insertions(+), 45 deletions(-) > >>>> > >>>> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index > >>>> cee4c0b59f43..4e3d39956185 100644 > >>>> --- a/drivers/mmc/core/sd.c > >>>> +++ b/drivers/mmc/core/sd.c > >>>> @@ -1001,18 +1001,6 @@ unsigned mmc_sd_get_max_clock(struct > >>>> mmc_card > >> *card) > >>>> return max_dtr; > >>>> } > >>>> > >>>> -static bool mmc_sd_card_using_v18(struct mmc_card *card) -{ > >>>> - /* > >>>> - * According to the SD spec., the Bus Speed Mode (function group 1) > >>>> bits > >>>> - * 2 to 4 are zero if the card is initialized at 3.3V signal level. > >>>> Thus > >>>> - * they can be used to determine if the card has already switched > >>>> to > >>>> - * 1.8V signaling. > >>>> - */ > >>>> - return card->sw_caps.sd3_bus_mode & > >>>> - (SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR104 | SD_MODE_UHS_DDR50); > >>>> -} > >>>> - > >>>> static int sd_write_ext_reg(struct mmc_card *card, u8 fno, u8 > >>>> page, > >>>> u16 offset, > >>>> u8 reg_data) > >>>> { > >>>> @@ -1400,10 +1388,9 @@ static int mmc_sd_init_card(struct mmc_host > >>>> *host, > >>>> u32 ocr, > >>>> int err; > >>>> u32 cid[4]; > >>>> u32 rocr = 0; > >>>> - bool v18_fixup_failed = false; > >>>> > >>>> WARN_ON(!host->claimed); > >>>> -retry: > >>>> + > >>>> err = mmc_sd_get_cid(host, ocr, cid, &rocr); > >>>> if (err) > >>>> return err; > >>>> @@ -1472,36 +1459,6 @@ static int mmc_sd_init_card(struct mmc_host > >>>> *host, > >>>> u32 ocr, > >>>> if (err) > >>>> goto free_card; > >>>> > >>>> - /* > >>>> - * If the card has not been power cycled, it may still be using > >>>> 1.8V > >>>> - * signaling. Detect that situation and try to initialize a UHS-I > >>>> (1.8V) > >>>> - * transfer mode. > >>>> - */ > >>>> - if (!v18_fixup_failed && !mmc_host_is_spi(host) && > >>>> mmc_host_uhs(host) && > >>>> - mmc_sd_card_using_v18(card) && > >>>> - host->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_180) { > >>>> - /* > >>>> - * Re-read switch information in case it has changed since > >>>> - * oldcard was initialized. > >>>> - */ > >>>> - if (oldcard) { > >>>> - err = mmc_read_switch(card); > >>>> - if (err) > >>>> - goto free_card; > >>>> - } > >>>> - if (mmc_sd_card_using_v18(card)) { > >>>> - if (mmc_host_set_uhs_voltage(host) || > >>>> - mmc_sd_init_uhs_card(card)) { > >>>> - v18_fixup_failed = true; > >>>> - mmc_power_cycle(host, ocr); > >>>> - if (!oldcard) > >>>> - mmc_remove_card(card); > >>>> - goto retry; > >>>> - } > >>>> - goto done; > >>>> - } > >>>> - } > >>>> - > >>>> /* Initialization sequence for UHS-I cards */ > >>>> if (rocr & SD_ROCR_S18A && mmc_host_uhs(host)) { > >>>> err = mmc_sd_init_uhs_card(card); @@ -1566,7 +1523,7 @@ > static > >>>> int mmc_sd_init_card(struct mmc_host *host, > >>>> u32 ocr, > >>>> err = -EINVAL; > >>>> goto free_card; > >>>> } > >>>> -done: > >>>> + > >>>> host->card = card; > >>>> return 0; > >>>> > >>>> -- > >>>> 2.29.0 > >>> > >>> Dear All, > >>> > >>> Please review this commit. > >> > >> I have started to look at it, but my time is limited at the moment. > >> > >> Note the original patch is 5 years old and fixes a real problem, so > >> we don't want to just throw it away. > >> > > > > Dear Mr. hunter, > > > > Could you check this with below patch? > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/com > > mit/drivers/mmc/core/core.c?id=147186f531ae49c18b7a9091a2c40e83b3d9564 > > 9 > > > > In the mmc_set_uhs_voltaga func(), > > once it occurs error, it has power_cycle except R1_ERROR with CMD11. > > So, When mmc_set_uhs_voltage() return error, host and card can't leave > > 1.8V voltage. > > > > Regards, > > > >>> > >>> Once the SDR104 SD card fails to switch voltage, there is no chance > >>> to work SDR104 bus speed again due to update sd3_bus_mode. > >>> > >>> To fix this regression issue, do not update sd3_bus_mode. > >>> And then it has the chance to work SDR104 again. > >>> > >>> AS-IS: > >>> voltage_switch fail -> mmc_read_switch() -> HS mode next system > >>> resume voltage switch success -> SDR25 mode > >>> > >>> TO-BE: > >>> Voltage switch fail -> HS mode > >>> Next system resume > >>> Voltage switch success -> SDR104 mode > >>> > >>> And plus, mmc_set_uhs_voltage() has power_cycle now. > >>> It means that if voltage switch fails, the card initializes 3.3V > >>> signal level. > >>> > >>> Regards, > >>> Seunghui Lee. > >>> > > > > > > Does this help? > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index > cee4c0b59f43..1abe8af48bfc 100644 > --- a/drivers/mmc/core/sd.c > +++ b/drivers/mmc/core/sd.c > @@ -949,15 +949,15 @@ int mmc_sd_setup_card(struct mmc_host *host, struct > mmc_card *card, > > /* Erase init depends on CSD and SSR */ > mmc_init_erase(card); > - > - /* > - * Fetch switch information from card. > - */ > - err = mmc_read_switch(card); > - if (err) > - return err; > } > > + /* > + * Fetch switch information from card. > + */ > + err = mmc_read_switch(card); > + if (err) > + return err; > + > /* > * For SPI, enable CRC as appropriate. > * This CRC enable is located AFTER the reading of the Dear Mr.Hunter, Your suggestion works well :) I've tested and verified the sd3_bus_mode's value updated. So, May I update your suggestion as patch v2? Or Would you like to your patch to contribute? Regards, Here is the test log. [ 2347.726601] [4: kworker/4:98: 2227] [TEST] mmc_sd_get_cid: ocr 0x41040000(pocr 0x40000), retries 0. [ 2347.726608] [4: kworker/4:98: 2227] mmc0: Skipping voltage switch [ 2347.932495] [4: kworker/4:98: 2227] [TEST] mmc_read_switch: sd_switch ret 0, sd3_bus_mode=0x3. [ 2347.932508] [4: kworker/4:98: 2227] [TEST] mmc_sd_init_card: 1116: caps=0x407f020f, sd3_bus_mode=0x3, v18_fixup_failed false, signal_voltage =0x0. -> sd3_bus_mode is 0x3. [ 2347.932514] [4: kworker/4:98: 2227] [TEST] mmc_sd_init_card: 1154: switch hs. [ 2347.936315] [4: kworker/4:98: 2227] [TEST] mmc_sd_init_card: 1198: card->ocr 0x40000. * next resume [ 2348.156021] [0: kworker/0:6:26086] [TEST] mmc_sd_init_card: 1037: card->ocr 0x40000. [ 2348.156065] [0: kworker/0:6:26086] [TEST] mmc_sd_get_cid: ocr 0x40000(pocr 0x40000), retries 10. [ 2348.387214] [0: kworker/0:6:26086] [TEST] mmc_read_switch: sd_switch ret 0, sd3_bus_mode=0x1f. -> sd3_bus_mode is 0x1f [ 2348.387253] [0: kworker/0:6:26086] [TEST] mmc_sd_init_card: 1116: caps=0x407f020f, sd3_bus_mode=0x1f, v18_fixup_failed false, signal_voltage =0x1. [ 2348.387273] [0: kworker/0:6:26086] [TEST] mmc_sd_init_card: 1146: rocr 0xc1ff8000, S18A, uhs. [ 2348.388399] [0: kworker/0:6:26086] [TEST] mmc_sd_init_uhs_card: before update: caps 0x407f020f, sd3_bus_mode = 0x1f, sd_bus_speed = 3, card->ocr = 0x40000. [ 2348.388427] [0: kworker/0:6:26086] [TEST] sd_update_bus_speed_mode: caps 0x407f020f, sd3_bus_mode = 0x1f, sd_bus_speed = 3, card->ocr = 0x40000. [ 2348.390614] [0: kworker/0:6:26086] [TEST] sd_set_bus_speed_mode: sd_bus_speed=3, timing=6, uhs_max_dtr=208000000, card->ocr=0x40000. [ 2348.393757] [0: kworker/0:6:26086] [TEST] mmc_sd_init_card: 1198: card->ocr 0x40000.
