mmc: Allow host drivers to specify max block count
Many controllers have an upper limit on the number of blocks that can be
transferred in one request. Allow the host drivers to specify this and make
sure we avoid hitting this limit.
Also change the max_sectors field to avoid confusion. This makes it map
less directly to the block layer limits, but as they didn't apply directly
on MMC cards anyway, this isn't a great loss.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/at91_mci.c b/drivers/mmc/at91_mci.c
index e28850d..2ce50f3 100644
--- a/drivers/mmc/at91_mci.c
+++ b/drivers/mmc/at91_mci.c
@@ -824,6 +824,7 @@
mmc->caps = MMC_CAP_BYTEBLOCK;
mmc->max_blk_size = 4095;
+ mmc->max_blk_count = mmc->max_req_size;
host = mmc_priv(mmc);
host->mmc = mmc;
diff --git a/drivers/mmc/au1xmmc.c b/drivers/mmc/au1xmmc.c
index 74e6ac0..b834be2 100644
--- a/drivers/mmc/au1xmmc.c
+++ b/drivers/mmc/au1xmmc.c
@@ -923,6 +923,7 @@
mmc->max_phys_segs = AU1XMMC_DESCRIPTOR_COUNT;
mmc->max_blk_size = 2048;
+ mmc->max_blk_count = 512;
mmc->ocr_avail = AU1XMMC_OCR;
diff --git a/drivers/mmc/imxmmc.c b/drivers/mmc/imxmmc.c
index 2107f8a..b060d4b 100644
--- a/drivers/mmc/imxmmc.c
+++ b/drivers/mmc/imxmmc.c
@@ -958,9 +958,10 @@
/* MMC core transfer sizes tunable parameters */
mmc->max_hw_segs = 64;
mmc->max_phys_segs = 64;
- mmc->max_sectors = 64; /* default 1 << (PAGE_CACHE_SHIFT - 9) */
mmc->max_seg_size = 64*512; /* default PAGE_CACHE_SIZE */
+ mmc->max_req_size = 64*512; /* default PAGE_CACHE_SIZE */
mmc->max_blk_size = 2048;
+ mmc->max_blk_count = 65535;
host = mmc_priv(mmc);
host->mmc = mmc;
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 9bda3fd..fb04bdd 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -109,6 +109,9 @@
mrq->cmd->mrq = mrq;
if (mrq->data) {
BUG_ON(mrq->data->blksz > host->max_blk_size);
+ BUG_ON(mrq->data->blocks > host->max_blk_count);
+ BUG_ON(mrq->data->blocks * mrq->data->blksz >
+ host->max_req_size);
mrq->cmd->data = mrq->data;
mrq->data->error = 0;
@@ -1605,10 +1608,11 @@
*/
host->max_hw_segs = 1;
host->max_phys_segs = 1;
- host->max_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
host->max_seg_size = PAGE_CACHE_SIZE;
+ host->max_req_size = PAGE_CACHE_SIZE;
host->max_blk_size = 512;
+ host->max_blk_count = PAGE_CACHE_SIZE / 512;
}
return host;
diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c
index 5a4eaca..19ccfed 100644
--- a/drivers/mmc/mmc_block.c
+++ b/drivers/mmc/mmc_block.c
@@ -242,10 +242,12 @@
brq.cmd.arg <<= 9;
brq.cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
brq.data.blksz = 1 << md->block_bits;
- brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
brq.stop.opcode = MMC_STOP_TRANSMISSION;
brq.stop.arg = 0;
brq.stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
+ brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
+ if (brq.data.blocks > card->host->max_blk_count)
+ brq.data.blocks = card->host->max_blk_count;
mmc_set_data_timeout(&brq.data, card, rq_data_dir(req) != READ);
diff --git a/drivers/mmc/mmc_queue.c b/drivers/mmc/mmc_queue.c
index 3e35a43..c27e426 100644
--- a/drivers/mmc/mmc_queue.c
+++ b/drivers/mmc/mmc_queue.c
@@ -147,7 +147,7 @@
blk_queue_prep_rq(mq->queue, mmc_prep_request);
blk_queue_bounce_limit(mq->queue, limit);
- blk_queue_max_sectors(mq->queue, host->max_sectors);
+ blk_queue_max_sectors(mq->queue, host->max_req_size / 512);
blk_queue_max_phys_segments(mq->queue, host->max_phys_segs);
blk_queue_max_hw_segments(mq->queue, host->max_hw_segs);
blk_queue_max_segment_size(mq->queue, host->max_seg_size);
diff --git a/drivers/mmc/mmci.c b/drivers/mmc/mmci.c
index 5d48e00..5941dd9 100644
--- a/drivers/mmc/mmci.c
+++ b/drivers/mmc/mmci.c
@@ -524,21 +524,25 @@
/*
* Since we only have a 16-bit data length register, we must
* ensure that we don't exceed 2^16-1 bytes in a single request.
- * Choose 64 (512-byte) sectors as the limit.
*/
- mmc->max_sectors = 64;
+ mmc->max_req_size = 65535;
/*
* Set the maximum segment size. Since we aren't doing DMA
* (yet) we are only limited by the data length register.
*/
- mmc->max_seg_size = mmc->max_sectors << 9;
+ mmc->max_seg_size = mmc->max_req_size;
/*
* Block size can be up to 2048 bytes, but must be a power of two.
*/
mmc->max_blk_size = 2048;
+ /*
+ * No limit on the number of blocks transferred.
+ */
+ mmc->max_blk_count = mmc->max_req_size;
+
spin_lock_init(&host->lock);
writel(0, host->base + MMCIMASK0);
diff --git a/drivers/mmc/omap.c b/drivers/mmc/omap.c
index fa69a0d..1e96a2f 100644
--- a/drivers/mmc/omap.c
+++ b/drivers/mmc/omap.c
@@ -1100,8 +1100,9 @@
mmc->max_phys_segs = 32;
mmc->max_hw_segs = 32;
mmc->max_blk_size = 2048; /* BLEN is 11 bits (+1) */
- mmc->max_sectors = 256; /* NBLK max 11-bits, OMAP also limited by DMA */
- mmc->max_seg_size = mmc->max_sectors * 512;
+ mmc->max_blk_count = 2048; /* NBLK is 11 bits (+1) */
+ mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
+ mmc->max_seg_size = mmc->max_req_size;
if (host->power_pin >= 0) {
if ((ret = omap_request_gpio(host->power_pin)) != 0) {
diff --git a/drivers/mmc/pxamci.c b/drivers/mmc/pxamci.c
index 9fc9aed..9774fc6 100644
--- a/drivers/mmc/pxamci.c
+++ b/drivers/mmc/pxamci.c
@@ -455,6 +455,11 @@
*/
mmc->max_blk_size = 1023;
+ /*
+ * Block count register is 16 bits.
+ */
+ mmc->max_blk_count = 65535;
+
host = mmc_priv(mmc);
host->mmc = mmc;
host->dma = -1;
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 155aafe..99f1db9 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -1333,15 +1333,15 @@
/*
* Maximum number of sectors in one transfer. Limited by DMA boundary
- * size (512KiB), which means (512 KiB/512=) 1024 entries.
+ * size (512KiB).
*/
- mmc->max_sectors = 1024;
+ mmc->max_req_size = 524288;
/*
* Maximum segment size. Could be one segment with the maximum number
- * of sectors.
+ * of bytes.
*/
- mmc->max_seg_size = mmc->max_sectors * 512;
+ mmc->max_seg_size = mmc->max_req_size;
/*
* Maximum block size. This varies from controller to controller and
@@ -1357,6 +1357,11 @@
mmc->max_blk_size = 512 << mmc->max_blk_size;
/*
+ * Maximum block count.
+ */
+ mmc->max_blk_count = 65535;
+
+ /*
* Init tasklets.
*/
tasklet_init(&host->card_tasklet,
diff --git a/drivers/mmc/tifm_sd.c b/drivers/mmc/tifm_sd.c
index bdfad15..7e607b7 100644
--- a/drivers/mmc/tifm_sd.c
+++ b/drivers/mmc/tifm_sd.c
@@ -885,10 +885,13 @@
mmc->f_max = 24000000;
mmc->max_hw_segs = 1;
mmc->max_phys_segs = 1;
- mmc->max_sectors = 127;
- //2k maximum hw block length
- mmc->max_seg_size = mmc->max_sectors << 11;
+ // limited by DMA counter - it's safer to stick with
+ // block counter has 11 bits though
+ mmc->max_blk_count = 256;
+ // 2k maximum hw block length
mmc->max_blk_size = 2048;
+ mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
+ mmc->max_seg_size = mmc->max_req_size;
sock->signal_irq = tifm_sd_signal_irq;
rc = tifm_sd_initialize_host(host);
diff --git a/drivers/mmc/wbsd.c b/drivers/mmc/wbsd.c
index 5711bee..cf16e44 100644
--- a/drivers/mmc/wbsd.c
+++ b/drivers/mmc/wbsd.c
@@ -1343,16 +1343,15 @@
mmc->max_phys_segs = 128;
/*
- * Maximum number of sectors in one transfer. Also limited by 64kB
- * buffer.
+ * Maximum request size. Also limited by 64KiB buffer.
*/
- mmc->max_sectors = 128;
+ mmc->max_req_size = 65536;
/*
* Maximum segment size. Could be one segment with the maximum number
- * of segments.
+ * of bytes.
*/
- mmc->max_seg_size = mmc->max_sectors * 512;
+ mmc->max_seg_size = mmc->max_req_size;
/*
* Maximum block size. We have 12 bits (= 4095) but have to subtract
@@ -1360,6 +1359,12 @@
*/
mmc->max_blk_size = 4087;
+ /*
+ * Maximum block count. There is no real limit so the maximum
+ * request size will be the only restriction.
+ */
+ mmc->max_blk_count = mmc->max_req_size;
+
dev_set_drvdata(dev, mmc);
return 0;
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 2da0c91..913e575 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -92,9 +92,10 @@
unsigned int max_seg_size; /* see blk_queue_max_segment_size */
unsigned short max_hw_segs; /* see blk_queue_max_hw_segments */
unsigned short max_phys_segs; /* see blk_queue_max_phys_segments */
- unsigned short max_sectors; /* see blk_queue_max_sectors */
unsigned short unused;
+ unsigned int max_req_size; /* maximum number of bytes in one req */
unsigned int max_blk_size; /* maximum size of one mmc block */
+ unsigned int max_blk_count; /* maximum number of blocks in one req */
/* private data */
struct mmc_ios ios; /* current io bus settings */