diff options
author | Ying-Chun Liu (PaulLiu) <paulliu@debian.org> | 2019-02-12 22:41:06 +0800 |
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committer | Ying-Chun Liu (PaulLiu) <paulliu@debian.org> | 2019-02-27 01:06:57 +0800 |
commit | 2c8ef2ae6b8103da5b6b82b2252877d61c2522bf (patch) | |
tree | bea32a4d9767a86df3e41b09ee0ad36055f8aabe /drivers | |
parent | ab3d22473df279c61ed4d4873d26b072dcf887e8 (diff) | |
download | trusted-firmware-a-2c8ef2ae6b8103da5b6b82b2252877d61c2522bf.tar.gz |
rpi3: sdhost: SDHost driver improvement
This commit improves the SDHost driver for RPi3 as following:
* Unblock MMC_CMD(17). Using MMC_CMD(17) is more efficient on
block reading.
* In some low probability that SEND_OP_COND might results CRC7
error. We can consider that the command runs correctly. We don't
need to retry this command so removing the code for retry.
* Using MMC_BUS_WIDTH_1 as MMC default value to improve the stability.
* Increase the clock to 50Mhz in data mode to speed up the io.
* Change the pull resistors configuration to gain more stability.
Signed-off-by: Ying-Chun Liu (PaulLiu) <paulliu@debian.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/rpi3/sdhost/rpi3_sdhost.c | 50 |
1 files changed, 20 insertions, 30 deletions
diff --git a/drivers/rpi3/sdhost/rpi3_sdhost.c b/drivers/rpi3/sdhost/rpi3_sdhost.c index efcd6dbb0e..c4b6fcafec 100644 --- a/drivers/rpi3/sdhost/rpi3_sdhost.c +++ b/drivers/rpi3/sdhost/rpi3_sdhost.c @@ -272,8 +272,6 @@ static int rpi3_sdhost_send_cmd(struct mmc_cmd *cmd) } cmd_idx = cmd->cmd_idx & HC_CMD_COMMAND_MASK; - if (cmd_idx == MMC_CMD(17)) - cmd_idx = MMC_CMD(18); cmd_arg = cmd->cmd_arg; if (cmd_idx == MMC_ACMD(51)) { @@ -364,8 +362,12 @@ static int rpi3_sdhost_send_cmd(struct mmc_cmd *cmd) mmio_write_32(reg_base + HC_HOSTSTATUS, HC_HSTST_MASK_ERROR_ALL); + /* + * If the command SEND_OP_COND returns with CRC7 error, + * it can be considered as having completed successfully. + */ if (!(sdhsts & HC_HSTST_ERROR_CRC7) - || (cmd_idx != MMC_ACMD(51))) { + || (cmd_idx != MMC_CMD(1))) { if (sdhsts & HC_HSTST_TIMEOUT_CMD) { ERROR("rpi3_sdhost: timeout status 0x%x\n", sdhsts); @@ -533,21 +535,6 @@ static int rpi3_sdhost_read(int lba, uintptr_t buf, size_t size) if (rpi3_sdhost_params.current_cmd == MMC_CMD(18)) send_command_decorated(MMC_CMD(12), 0); - if (err == -(EILSEQ)) { - const int max_retries = 20; - int r; - - rpi3_sdhost_params.crc_err_retries++; - if (rpi3_sdhost_params.crc_err_retries < max_retries) { - /* retries if there's an CRC error */ - r = rpi3_sdhost_prepare(lba, buf, size); - send_command_decorated(MMC_CMD(18), lba); - r = rpi3_sdhost_read(lba, buf, size); - if (r == 0) - err = 0; - } - } - return err; } @@ -617,16 +604,20 @@ void rpi3_sdhost_init(struct rpi3_sdhost_params *params, } /* setting pull resistors for 48 to 53. - * GPIO 48 (SD_CLK) to GPIO_PULL_UP - * GPIO 49 (SD_CMD) to GPIO_PULL_NONE - * GPIO 50 (SD_D0) to GPIO_PULL_NONE - * GPIO 51 (SD_D1) to GPIO_PULL_NONE - * GPIO 52 (SD_D2) to GPIO_PULL_NONE - * GPIO 53 (SD_D3) to GPIO_PULL_NONE + * It is debatable to set SD_CLK to UP or NONE. We massively + * tested different brands of SD Cards and found NONE works + * most stable. + * + * GPIO 48 (SD_CLK) to GPIO_PULL_NONE + * GPIO 49 (SD_CMD) to GPIO_PULL_UP + * GPIO 50 (SD_D0) to GPIO_PULL_UP + * GPIO 51 (SD_D1) to GPIO_PULL_UP + * GPIO 52 (SD_D2) to GPIO_PULL_UP + * GPIO 53 (SD_D3) to GPIO_PULL_UP */ - gpio_set_pull(48, GPIO_PULL_UP); + gpio_set_pull(48, GPIO_PULL_NONE); for (int i = 49; i <= 53; i++) - gpio_set_pull(i, GPIO_PULL_NONE); + gpio_set_pull(i, GPIO_PULL_UP); /* Set pin 48-53 to alt-0. It means route SDHOST to card slot */ for (int i = 48; i <= 53; i++) @@ -675,15 +666,14 @@ void rpi3_sdhost_stop(void) rpi3_sdhost_params.gpio48_pinselect[i-48]); } - /* Must reset the pull resistors for u-boot to work. - * GPIO 48 (SD_CLK) to GPIO_PULL_NONE + /* Reset the pull resistors before entering BL33. + * GPIO 48 (SD_CLK) to GPIO_PULL_UP * GPIO 49 (SD_CMD) to GPIO_PULL_UP * GPIO 50 (SD_D0) to GPIO_PULL_UP * GPIO 51 (SD_D1) to GPIO_PULL_UP * GPIO 52 (SD_D2) to GPIO_PULL_UP * GPIO 53 (SD_D3) to GPIO_PULL_UP */ - gpio_set_pull(48, GPIO_PULL_NONE); - for (int i = 49; i <= 53; i++) + for (int i = 48; i <= 53; i++) gpio_set_pull(i, GPIO_PULL_UP); } |