diff options
author | Che-Liang Chiou <clchiou@chromium.org> | 2012-11-28 15:21:13 (GMT) |
---|---|---|
committer | Andy Fleming <afleming@freescale.com> | 2013-05-06 21:12:38 (GMT) |
commit | e95504497ecac46907204b0ee3460b708a2981ac (patch) | |
tree | c59e230a6096b5883c83d3399717a3408f601355 /drivers | |
parent | 5ed6f447af60aabd2669d913f673793c1ce48f47 (diff) | |
download | u-boot-fsl-qoriq-e95504497ecac46907204b0ee3460b708a2981ac.tar.xz |
mmc: Split device init to decouple OCR-polling delay
Most of time that MMC driver spends on initializing a device is polling
OCR (operation conditions register). To decouple this polling loop,
device init is split into two parts: The first part fires the OCR query
command, and the second part polls the result. So the caller is now no
longer bound to the OCR-polling delay; he may fire the query, go
somewhere and then come back later for the result.
To use this, call mmc_set_preinit() on any device which needs this.
This can save significant amounts of time on boot (e.g. 200ms) by
hiding the MMC init time behind other init.
Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/mmc/mmc.c | 137 |
1 files changed, 105 insertions, 32 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 2590f1b..0a2f535 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -524,48 +524,70 @@ static int sd_send_op_cond(struct mmc *mmc) return 0; } -static int mmc_send_op_cond(struct mmc *mmc) +/* We pass in the cmd since otherwise the init seems to fail */ +static int mmc_send_op_cond_iter(struct mmc *mmc, struct mmc_cmd *cmd, + int use_arg) { - int timeout = 10000; - struct mmc_cmd cmd; int err; + cmd->cmdidx = MMC_CMD_SEND_OP_COND; + cmd->resp_type = MMC_RSP_R3; + cmd->cmdarg = 0; + if (use_arg && !mmc_host_is_spi(mmc)) { + cmd->cmdarg = + (mmc->voltages & + (mmc->op_cond_response & OCR_VOLTAGE_MASK)) | + (mmc->op_cond_response & OCR_ACCESS_MODE); + + if (mmc->host_caps & MMC_MODE_HC) + cmd->cmdarg |= OCR_HCS; + } + err = mmc_send_cmd(mmc, cmd, NULL); + if (err) + return err; + mmc->op_cond_response = cmd->response[0]; + return 0; +} + +int mmc_send_op_cond(struct mmc *mmc) +{ + struct mmc_cmd cmd; + int err, i; + /* Some cards seem to need this */ mmc_go_idle(mmc); /* Asking to the card its capabilities */ - cmd.cmdidx = MMC_CMD_SEND_OP_COND; - cmd.resp_type = MMC_RSP_R3; - cmd.cmdarg = 0; - - err = mmc_send_cmd(mmc, &cmd, NULL); + mmc->op_cond_pending = 1; + for (i = 0; i < 2; i++) { + err = mmc_send_op_cond_iter(mmc, &cmd, i != 0); + if (err) + return err; - if (err) - return err; + /* exit if not busy (flag seems to be inverted) */ + if (mmc->op_cond_response & OCR_BUSY) + return 0; + } + return IN_PROGRESS; +} - udelay(1000); +int mmc_complete_op_cond(struct mmc *mmc) +{ + struct mmc_cmd cmd; + int timeout = 1000; + uint start; + int err; + mmc->op_cond_pending = 0; + start = get_timer(0); do { - cmd.cmdidx = MMC_CMD_SEND_OP_COND; - cmd.resp_type = MMC_RSP_R3; - cmd.cmdarg = (mmc_host_is_spi(mmc) ? 0 : - (mmc->voltages & - (cmd.response[0] & OCR_VOLTAGE_MASK)) | - (cmd.response[0] & OCR_ACCESS_MODE)); - - if (mmc->host_caps & MMC_MODE_HC) - cmd.cmdarg |= OCR_HCS; - - err = mmc_send_cmd(mmc, &cmd, NULL); - + err = mmc_send_op_cond_iter(mmc, &cmd, 1); if (err) return err; - - udelay(1000); - } while (!(cmd.response[0] & OCR_BUSY) && timeout--); - - if (timeout <= 0) - return UNUSABLE_ERR; + if (get_timer(start) > timeout) + return UNUSABLE_ERR; + udelay(100); + } while (!(mmc->op_cond_response & OCR_BUSY)); if (mmc_host_is_spi(mmc)) { /* read OCR for spi */ cmd.cmdidx = MMC_CMD_SPI_READ_OCR; @@ -1274,7 +1296,7 @@ block_dev_desc_t *mmc_get_dev(int dev) } #endif -int mmc_init(struct mmc *mmc) +int mmc_start_init(struct mmc *mmc) { int err; @@ -1314,17 +1336,48 @@ int mmc_init(struct mmc *mmc) if (err == TIMEOUT) { err = mmc_send_op_cond(mmc); - if (err) { + if (err && err != IN_PROGRESS) { printf("Card did not respond to voltage select!\n"); return UNUSABLE_ERR; } } - err = mmc_startup(mmc); + if (err == IN_PROGRESS) + mmc->init_in_progress = 1; + + return err; +} + +static int mmc_complete_init(struct mmc *mmc) +{ + int err = 0; + + if (mmc->op_cond_pending) + err = mmc_complete_op_cond(mmc); + + if (!err) + err = mmc_startup(mmc); if (err) mmc->has_init = 0; else mmc->has_init = 1; + mmc->init_in_progress = 0; + return err; +} + +int mmc_init(struct mmc *mmc) +{ + int err = IN_PROGRESS; + unsigned start = get_timer(0); + + if (mmc->has_init) + return 0; + if (!mmc->init_in_progress) + err = mmc_start_init(mmc); + + if (!err || err == IN_PROGRESS) + err = mmc_complete_init(mmc); + debug("%s: %d, time %lu\n", __func__, err, get_timer(start)); return err; } @@ -1362,6 +1415,25 @@ int get_mmc_num(void) return cur_dev_num; } +void mmc_set_preinit(struct mmc *mmc, int preinit) +{ + mmc->preinit = preinit; +} + +static void do_preinit(void) +{ + struct mmc *m; + struct list_head *entry; + + list_for_each(entry, &mmc_devices) { + m = list_entry(entry, struct mmc, link); + + if (m->preinit) + mmc_start_init(m); + } +} + + int mmc_initialize(bd_t *bis) { INIT_LIST_HEAD (&mmc_devices); @@ -1372,5 +1444,6 @@ int mmc_initialize(bd_t *bis) print_mmc_devices(','); + do_preinit(); return 0; } |