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authorPierre Ossman <drzeus@drzeus.cx>2008-07-21 00:32:11 +0200
committerPierre Ossman <drzeus@drzeus.cx>2008-07-23 14:42:09 +0200
commit7659150c60839a2bd31f74e866374abb9be17e43 (patch)
tree76c07d0b7ea4c329930fad3d0ea9ed0341bb40eb /drivers/mmc
parent137d3edb48425f82a6a4226b664f90ed5e42eea5 (diff)
sdhci: highmem capable PIO routines
Improve the PIO handling so that it can service highmem pages. Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Diffstat (limited to 'drivers/mmc')
-rw-r--r--drivers/mmc/host/sdhci.c163
-rw-r--r--drivers/mmc/host/sdhci.h7
2 files changed, 75 insertions, 95 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 8b1f412144c..c3a5db72ddd 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -173,119 +173,95 @@ static void sdhci_led_control(struct led_classdev *led,
* *
\*****************************************************************************/
-static inline char* sdhci_sg_to_buffer(struct sdhci_host* host)
-{
- return sg_virt(host->cur_sg);
-}
-
-static inline int sdhci_next_sg(struct sdhci_host* host)
-{
- /*
- * Skip to next SG entry.
- */
- host->cur_sg++;
- host->num_sg--;
-
- /*
- * Any entries left?
- */
- if (host->num_sg > 0) {
- host->offset = 0;
- host->remain = host->cur_sg->length;
- }
-
- return host->num_sg;
-}
-
static void sdhci_read_block_pio(struct sdhci_host *host)
{
- int blksize, chunk_remain;
- u32 data;
- char *buffer;
- int size;
+ unsigned long flags;
+ size_t blksize, len, chunk;
+ u32 scratch;
+ u8 *buf;
DBG("PIO reading\n");
blksize = host->data->blksz;
- chunk_remain = 0;
- data = 0;
+ chunk = 0;
- buffer = sdhci_sg_to_buffer(host) + host->offset;
+ local_irq_save(flags);
while (blksize) {
- if (chunk_remain == 0) {
- data = readl(host->ioaddr + SDHCI_BUFFER);
- chunk_remain = min(blksize, 4);
- }
+ if (!sg_miter_next(&host->sg_miter))
+ BUG();
- size = min(host->remain, chunk_remain);
+ len = min(host->sg_miter.length, blksize);
- chunk_remain -= size;
- blksize -= size;
- host->offset += size;
- host->remain -= size;
+ blksize -= len;
+ host->sg_miter.consumed = len;
- while (size) {
- *buffer = data & 0xFF;
- buffer++;
- data >>= 8;
- size--;
- }
+ buf = host->sg_miter.addr;
- if (host->remain == 0) {
- if (sdhci_next_sg(host) == 0) {
- BUG_ON(blksize != 0);
- return;
+ while (len) {
+ if (chunk == 0) {
+ scratch = readl(host->ioaddr + SDHCI_BUFFER);
+ chunk = 4;
}
- buffer = sdhci_sg_to_buffer(host);
+
+ *buf = scratch & 0xFF;
+
+ buf++;
+ scratch >>= 8;
+ chunk--;
+ len--;
}
}
+
+ sg_miter_stop(&host->sg_miter);
+
+ local_irq_restore(flags);
}
static void sdhci_write_block_pio(struct sdhci_host *host)
{
- int blksize, chunk_remain;
- u32 data;
- char *buffer;
- int bytes, size;
+ unsigned long flags;
+ size_t blksize, len, chunk;
+ u32 scratch;
+ u8 *buf;
DBG("PIO writing\n");
blksize = host->data->blksz;
- chunk_remain = 4;
- data = 0;
+ chunk = 0;
+ scratch = 0;
- bytes = 0;
- buffer = sdhci_sg_to_buffer(host) + host->offset;
+ local_irq_save(flags);
while (blksize) {
- size = min(host->remain, chunk_remain);
-
- chunk_remain -= size;
- blksize -= size;
- host->offset += size;
- host->remain -= size;
-
- while (size) {
- data >>= 8;
- data |= (u32)*buffer << 24;
- buffer++;
- size--;
- }
+ if (!sg_miter_next(&host->sg_miter))
+ BUG();
- if (chunk_remain == 0) {
- writel(data, host->ioaddr + SDHCI_BUFFER);
- chunk_remain = min(blksize, 4);
- }
+ len = min(host->sg_miter.length, blksize);
+
+ blksize -= len;
+ host->sg_miter.consumed = len;
+
+ buf = host->sg_miter.addr;
- if (host->remain == 0) {
- if (sdhci_next_sg(host) == 0) {
- BUG_ON(blksize != 0);
- return;
+ while (len) {
+ scratch |= (u32)*buf << (chunk * 8);
+
+ buf++;
+ chunk++;
+ len--;
+
+ if ((chunk == 4) || ((len == 0) && (blksize == 0))) {
+ writel(scratch, host->ioaddr + SDHCI_BUFFER);
+ chunk = 0;
+ scratch = 0;
}
- buffer = sdhci_sg_to_buffer(host);
}
}
+
+ sg_miter_stop(&host->sg_miter);
+
+ local_irq_restore(flags);
}
static void sdhci_transfer_pio(struct sdhci_host *host)
@@ -294,7 +270,7 @@ static void sdhci_transfer_pio(struct sdhci_host *host)
BUG_ON(!host->data);
- if (host->num_sg == 0)
+ if (host->blocks == 0)
return;
if (host->data->flags & MMC_DATA_READ)
@@ -308,7 +284,8 @@ static void sdhci_transfer_pio(struct sdhci_host *host)
else
sdhci_write_block_pio(host);
- if (host->num_sg == 0)
+ host->blocks--;
+ if (host->blocks == 0)
break;
}
@@ -713,11 +690,9 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
}
if (!(host->flags & SDHCI_REQ_USE_DMA)) {
- host->cur_sg = data->sg;
- host->num_sg = data->sg_len;
-
- host->offset = 0;
- host->remain = host->cur_sg->length;
+ sg_miter_start(&host->sg_miter,
+ data->sg, data->sg_len, SG_MITER_ATOMIC);
+ host->blocks = data->blocks;
}
/* We do not handle DMA boundaries, so set it to max (512 KiB) */
@@ -1583,9 +1558,15 @@ int sdhci_add_host(struct sdhci_host *host)
}
}
- /* XXX: Hack to get MMC layer to avoid highmem */
- if (!(host->flags & SDHCI_USE_DMA))
- mmc_dev(host->mmc)->dma_mask = NULL;
+ /*
+ * If we use DMA, then it's up to the caller to set the DMA
+ * mask, but PIO does not need the hw shim so we set a new
+ * mask here in that case.
+ */
+ if (!(host->flags & SDHCI_USE_DMA)) {
+ host->dma_mask = DMA_BIT_MASK(64);
+ mmc_dev(host->mmc)->dma_mask = &host->dma_mask;
+ }
host->max_clk =
(caps & SDHCI_CLOCK_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 5bb35528176..a06bf8b8934 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -212,6 +212,7 @@ struct sdhci_host {
/* Internal data */
struct mmc_host *mmc; /* MMC structure */
+ u64 dma_mask; /* custom DMA mask */
#ifdef CONFIG_LEDS_CLASS
struct led_classdev led; /* LED control */
@@ -238,10 +239,8 @@ struct sdhci_host {
struct mmc_data *data; /* Current data request */
unsigned int data_early:1; /* Data finished before cmd */
- struct scatterlist *cur_sg; /* We're working on this */
- int num_sg; /* Entries left */
- int offset; /* Offset into current sg */
- int remain; /* Bytes left in current */
+ struct sg_mapping_iter sg_miter; /* SG state for PIO */
+ unsigned int blocks; /* remaining PIO blocks */
int sg_count; /* Mapped sg entries */