diff options
| author | Pierre Ossman <drzeus@drzeus.cx> | 2006-06-18 14:34:37 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2006-09-07 13:18:40 +0100 |
| commit | 385e3227d4d83ab13d7767c4bb3593b0256bf246 (patch) | |
| tree | 91f532e07753c44a905116f5a7d0e3bdcfca7f0a /drivers/mmc/mmc_block.c | |
| parent | f57b225e432d80ee46f48536cc55ea6cf62c5570 (diff) | |
[MMC] Fix SD timeout calculation
Secure Digital cards use a different algorithm to calculate the timeout
for data transfers. Using the MMC one works often, but not always.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/mmc/mmc_block.c')
| -rw-r--r-- | drivers/mmc/mmc_block.c | 44 |
1 files changed, 36 insertions, 8 deletions
diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c index 115cc21094b..515fb227eba 100644 --- a/drivers/mmc/mmc_block.c +++ b/drivers/mmc/mmc_block.c @@ -30,6 +30,7 @@ #include <linux/mutex.h> #include <linux/mmc/card.h> +#include <linux/mmc/host.h> #include <linux/mmc/protocol.h> #include <asm/system.h> @@ -171,8 +172,6 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) brq.cmd.arg = req->sector << 9; brq.cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC; - brq.data.timeout_ns = card->csd.tacc_ns * 10; - brq.data.timeout_clks = card->csd.tacc_clks * 10; brq.data.blksz_bits = md->block_bits; brq.data.blksz = 1 << md->block_bits; brq.data.blocks = req->nr_sectors >> (md->block_bits - 9); @@ -180,6 +179,41 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) brq.stop.arg = 0; brq.stop.flags = MMC_RSP_R1B | MMC_CMD_AC; + brq.data.timeout_ns = card->csd.tacc_ns * 10; + brq.data.timeout_clks = card->csd.tacc_clks * 10; + + /* + * Scale up the timeout by the r2w factor + */ + if (rq_data_dir(req) == WRITE) { + brq.data.timeout_ns <<= card->csd.r2w_factor; + brq.data.timeout_clks <<= card->csd.r2w_factor; + } + + /* + * SD cards use a 100 multiplier and has a upper limit + */ + if (mmc_card_sd(card)) { + unsigned int limit_us, timeout_us; + + brq.data.timeout_ns *= 10; + brq.data.timeout_clks *= 10; + + if (rq_data_dir(req) == READ) + limit_us = 100000; + else + limit_us = 250000; + + timeout_us = brq.data.timeout_ns / 1000; + timeout_us += brq.data.timeout_clks * 1000 / + (card->host->ios.clock / 1000); + + if (timeout_us > limit_us) { + brq.data.timeout_ns = limit_us * 1000; + brq.data.timeout_clks = 0; + } + } + if (rq_data_dir(req) == READ) { brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK; brq.data.flags |= MMC_DATA_READ; @@ -187,12 +221,6 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) brq.cmd.opcode = MMC_WRITE_BLOCK; brq.data.flags |= MMC_DATA_WRITE; brq.data.blocks = 1; - - /* - * Scale up the timeout by the r2w factor - */ - brq.data.timeout_ns <<= card->csd.r2w_factor; - brq.data.timeout_clks <<= card->csd.r2w_factor; } if (brq.data.blocks > 1) { |