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/commit/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
