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authorLinus Walleij <linus.walleij@stericsson.com>2011-01-24 15:22:13 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-01-24 15:23:00 +0000
commit8cb2815574278a1bf966f041cbfe5b7c91472dcd (patch)
tree540d5b544f8ffc401737c1938258d04e1c3eff57 /drivers/mmc/host/mmci.c
parent1bae4ce27c9c90344f23c65ea6966c50ffeae2f5 (diff)
downloadop-kernel-dev-8cb2815574278a1bf966f041cbfe5b7c91472dcd.zip
op-kernel-dev-8cb2815574278a1bf966f041cbfe5b7c91472dcd.tar.gz
ARM: 6632/3: mmci: stop using the blockend interrupts
Implement a suggestion from Russell to drop the use of blockend interrupts altogether and instead rely on the data counter. Tested with error-free cards on U300, U8500 and RealView PB1176. Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/mmc/host/mmci.c')
-rw-r--r--drivers/mmc/host/mmci.c98
1 files changed, 20 insertions, 78 deletions
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 5630228..2de12fe 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -46,10 +46,6 @@ static unsigned int fmax = 515633;
* is asserted (likewise for RX)
* @fifohalfsize: number of bytes that can be written when MCI_TXFIFOHALFEMPTY
* is asserted (likewise for RX)
- * @broken_blockend: the MCI_DATABLOCKEND is broken on the hardware
- * and will not work at all.
- * @broken_blockend_dma: the MCI_DATABLOCKEND is broken on the hardware when
- * using DMA.
* @sdio: variant supports SDIO
* @st_clkdiv: true if using a ST-specific clock divider algorithm
*/
@@ -59,8 +55,6 @@ struct variant_data {
unsigned int datalength_bits;
unsigned int fifosize;
unsigned int fifohalfsize;
- bool broken_blockend;
- bool broken_blockend_dma;
bool sdio;
bool st_clkdiv;
};
@@ -76,7 +70,6 @@ static struct variant_data variant_u300 = {
.fifohalfsize = 8 * 4,
.clkreg_enable = 1 << 13, /* HWFCEN */
.datalength_bits = 16,
- .broken_blockend_dma = true,
.sdio = true,
};
@@ -86,7 +79,6 @@ static struct variant_data variant_ux500 = {
.clkreg = MCI_CLK_ENABLE,
.clkreg_enable = 1 << 14, /* HWFCEN */
.datalength_bits = 24,
- .broken_blockend = true,
.sdio = true,
.st_clkdiv = true,
};
@@ -210,8 +202,6 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
host->data = data;
host->size = data->blksz * data->blocks;
host->data_xfered = 0;
- host->blockend = false;
- host->dataend = false;
mmci_init_sg(host, data);
@@ -288,21 +278,26 @@ static void
mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
unsigned int status)
{
- struct variant_data *variant = host->variant;
-
/* First check for errors */
if (status & (MCI_DATACRCFAIL|MCI_DATATIMEOUT|MCI_TXUNDERRUN|MCI_RXOVERRUN)) {
+ u32 remain, success;
+
+ /* Calculate how far we are into the transfer */
+ remain = readl(host->base + MMCIDATACNT) << 2;
+ success = data->blksz * data->blocks - remain;
+
dev_dbg(mmc_dev(host->mmc), "MCI ERROR IRQ (status %08x)\n", status);
- if (status & MCI_DATACRCFAIL)
+ if (status & MCI_DATACRCFAIL) {
+ /* Last block was not successful */
+ host->data_xfered = ((success / data->blksz) - 1 * data->blksz);
data->error = -EILSEQ;
- else if (status & MCI_DATATIMEOUT)
+ } else if (status & MCI_DATATIMEOUT) {
+ host->data_xfered = success;
data->error = -ETIMEDOUT;
- else if (status & (MCI_TXUNDERRUN|MCI_RXOVERRUN))
+ } else if (status & (MCI_TXUNDERRUN|MCI_RXOVERRUN)) {
+ host->data_xfered = success;
data->error = -EIO;
-
- /* Force-complete the transaction */
- host->blockend = true;
- host->dataend = true;
+ }
/*
* We hit an error condition. Ensure that any data
@@ -321,61 +316,14 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
}
}
- /*
- * On ARM variants in PIO mode, MCI_DATABLOCKEND
- * is always sent first, and we increase the
- * transfered number of bytes for that IRQ. Then
- * MCI_DATAEND follows and we conclude the transaction.
- *
- * On the Ux500 single-IRQ variant MCI_DATABLOCKEND
- * doesn't seem to immediately clear from the status,
- * so we can't use it keep count when only one irq is
- * used because the irq will hit for other reasons, and
- * then the flag is still up. So we use the MCI_DATAEND
- * IRQ at the end of the entire transfer because
- * MCI_DATABLOCKEND is broken.
- *
- * In the U300, the IRQs can arrive out-of-order,
- * e.g. MCI_DATABLOCKEND sometimes arrives after MCI_DATAEND,
- * so for this case we use the flags "blockend" and
- * "dataend" to make sure both IRQs have arrived before
- * concluding the transaction. (This does not apply
- * to the Ux500 which doesn't fire MCI_DATABLOCKEND
- * at all.) In DMA mode it suffers from the same problem
- * as the Ux500.
- */
- if (status & MCI_DATABLOCKEND) {
- /*
- * Just being a little over-cautious, we do not
- * use this progressive update if the hardware blockend
- * flag is unreliable: since it can stay high between
- * IRQs it will corrupt the transfer counter.
- */
- if (!variant->broken_blockend)
- host->data_xfered += data->blksz;
- host->blockend = true;
- }
-
- if (status & MCI_DATAEND)
- host->dataend = true;
+ if (status & MCI_DATABLOCKEND)
+ dev_err(mmc_dev(host->mmc), "stray MCI_DATABLOCKEND interrupt\n");
- /*
- * On variants with broken blockend we shall only wait for dataend,
- * on others we must sync with the blockend signal since they can
- * appear out-of-order.
- */
- if (host->dataend && (host->blockend || variant->broken_blockend)) {
+ if (status & MCI_DATAEND) {
mmci_stop_data(host);
- /* Reset these flags */
- host->blockend = false;
- host->dataend = false;
-
- /*
- * Variants with broken blockend flags need to handle the
- * end of the entire transfer here.
- */
- if (variant->broken_blockend && !data->error)
+ if (!data->error)
+ /* The error clause is handled above, success! */
host->data_xfered += data->blksz * data->blocks;
if (!data->stop) {
@@ -770,7 +718,6 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
struct variant_data *variant = id->data;
struct mmci_host *host;
struct mmc_host *mmc;
- unsigned int mask;
int ret;
/* must have platform data */
@@ -951,12 +898,7 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
goto irq0_free;
}
- mask = MCI_IRQENABLE;
- /* Don't use the datablockend flag if it's broken */
- if (variant->broken_blockend)
- mask &= ~MCI_DATABLOCKEND;
-
- writel(mask, host->base + MMCIMASK0);
+ writel(MCI_IRQENABLE, host->base + MMCIMASK0);
amba_set_drvdata(dev, mmc);
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