[PATCH] mmci: fixup broken_blockend variant patch v2
Linus Walleij
linus.walleij at stericsson.com
Mon Jan 17 09:37:51 EST 2011
From: Ulf Hansson <ulf.hansson at stericsson.com>
host->last_blockend flag is now set only for the last
MCI_DATABLOCKEND, the previous code would just react to
any blockend, which was buggy. Consolidate Ux500 and U300
bug flags to a single one and use only the MCI_DATAEND irq
on U300 as well, it turns out it was broken just like the
Ux500.
Also make sure the MCI_DATABLOCKENDMASK is set only when
needed, instead of being set always and then masked off.
Tested successfully on Ux500, U300 and ARM RealView
PB1176.
Cc: Sebastian Rasmussen <sebastian.rasmussen at stericsson.com>
Cc: Rabin Vincent <rabin.vincent at stericsson.com>
Signed-off-by: Ulf Hansson <ulf.hansson at stericsson.com>
[Tweaking and adding err message]
Signed-off-by: Linus Walleij <linus.walleij at stericsson.com>
---
v2: also updated the comment.
---
drivers/mmc/host/mmci.c | 93 +++++++++++++++++++++++++----------------------
drivers/mmc/host/mmci.h | 4 +-
2 files changed, 52 insertions(+), 45 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 0b4a5bf..7e0d38c 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -48,8 +48,6 @@ static unsigned int fmax = 515633;
* 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
*/
@@ -60,7 +58,6 @@ struct variant_data {
unsigned int fifosize;
unsigned int fifohalfsize;
bool broken_blockend;
- bool broken_blockend_dma;
bool sdio;
bool st_clkdiv;
};
@@ -76,7 +73,7 @@ static struct variant_data variant_u300 = {
.fifohalfsize = 8 * 4,
.clkreg_enable = 1 << 13, /* HWFCEN */
.datalength_bits = 16,
- .broken_blockend_dma = true,
+ .broken_blockend = true,
.sdio = true,
};
@@ -199,7 +196,7 @@ static void mmci_init_sg(struct mmci_host *host, struct mmc_data *data)
static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
{
struct variant_data *variant = host->variant;
- unsigned int datactrl, timeout, irqmask;
+ unsigned int datactrl, timeout, irqmask0, irqmask1;
unsigned long long clks;
void __iomem *base;
int blksz_bits;
@@ -210,7 +207,7 @@ 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->last_blockend = false;
host->dataend = false;
mmci_init_sg(host, data);
@@ -230,20 +227,20 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
datactrl = MCI_DPSM_ENABLE | blksz_bits << 4;
if (data->flags & MMC_DATA_READ) {
datactrl |= MCI_DPSM_DIRECTION;
- irqmask = MCI_RXFIFOHALFFULLMASK;
+ irqmask1 = MCI_RXFIFOHALFFULLMASK;
/*
* If we have less than a FIFOSIZE of bytes to transfer,
* trigger a PIO interrupt as soon as any data is available.
*/
if (host->size < variant->fifosize)
- irqmask |= MCI_RXDATAAVLBLMASK;
+ irqmask1 |= MCI_RXDATAAVLBLMASK;
} else {
/*
* We don't actually need to include "FIFO empty" here
* since its implicit in "FIFO half empty".
*/
- irqmask = MCI_TXFIFOHALFEMPTYMASK;
+ irqmask1 = MCI_TXFIFOHALFEMPTYMASK;
}
/* The ST Micro variants has a special bit to enable SDIO */
@@ -252,8 +249,14 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
datactrl |= MCI_ST_DPSM_SDIOEN;
writel(datactrl, base + MMCIDATACTRL);
- writel(readl(base + MMCIMASK0) & ~MCI_DATAENDMASK, base + MMCIMASK0);
- mmci_set_mask1(host, irqmask);
+ irqmask0 = readl(base + MMCIMASK0);
+ if (variant->broken_blockend)
+ irqmask0 &= ~MCI_DATABLOCKENDMASK;
+ else
+ irqmask0 |= MCI_DATABLOCKENDMASK;
+ irqmask0 &= ~MCI_DATAENDMASK;
+ writel(irqmask0, base + MMCIMASK0);
+ mmci_set_mask1(host, irqmask1);
}
static void
@@ -301,7 +304,7 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
data->error = -EIO;
/* Force-complete the transaction */
- host->blockend = true;
+ host->last_blockend = true;
host->dataend = true;
/*
@@ -322,27 +325,18 @@ 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 ARM variants in PIO mode, MCI_DATABLOCKEND is always sent first,
+ * and we increase the transfered number of bytes for that IRQ. Repeat
+ * for the number of blocks in the transfer. 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.
+ * On the U300 and Ux500 a few to many MCI_DATABLOCKEND interrupts
+ * are usually missing, so the data counter is not properly increased.
+ * This is likely because new block arrive while the IRQ is being
+ * processed without the transfers being held back, and ACK:in the
+ * interrupt will only clear the very last block and intermediate
+ * blockend interrupts get lost. So we simply mask of the blockend
+ * interrupt on these and only use the dataend interrupt.
*/
if (status & MCI_DATABLOCKEND) {
/*
@@ -353,22 +347,41 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
*/
if (!variant->broken_blockend)
host->data_xfered += data->blksz;
- host->blockend = true;
+ if (host->data_xfered == data->blksz * data->blocks)
+ host->last_blockend = true;
}
- if (status & MCI_DATAEND)
+ if (status & MCI_DATAEND) {
+ if (!host->last_blockend && !variant->broken_blockend &&
+ !data->error) {
+ /*
+ * This typically occur on hardware with broken
+ * blockend reporting, which will fire less blockend
+ * IRQs than would be expected. Print an error and
+ * repair the situation, but the hardware should
+ * really be flagged as broken so this IRQ is not used
+ * at all.
+ */
+ dev_err(mmc_dev(host->mmc),
+ "missing %d block interrupts!\n",
+ (data->blksz * data->blocks - host->data_xfered) / data->blksz);
+ host->data_xfered = data->blksz * data->blocks;
+ host->last_blockend = true;
+ }
host->dataend = true;
+ }
/*
* 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 (host->dataend &&
+ (host->last_blockend || variant->broken_blockend)) {
mmci_stop_data(host);
/* Reset these flags */
- host->blockend = false;
+ host->last_blockend = false;
host->dataend = false;
/*
@@ -770,7 +783,6 @@ 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 +963,7 @@ 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);
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index df06f01..7ac8c4d 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -137,7 +137,7 @@
#define MCI_IRQENABLE \
(MCI_CMDCRCFAILMASK|MCI_DATACRCFAILMASK|MCI_CMDTIMEOUTMASK| \
MCI_DATATIMEOUTMASK|MCI_TXUNDERRUNMASK|MCI_RXOVERRUNMASK| \
- MCI_CMDRESPENDMASK|MCI_CMDSENTMASK|MCI_DATABLOCKENDMASK)
+ MCI_CMDRESPENDMASK|MCI_CMDSENTMASK)
/* These interrupts are directed to IRQ1 when two IRQ lines are available */
#define MCI_IRQ1MASK \
@@ -177,7 +177,7 @@ struct mmci_host {
struct timer_list timer;
unsigned int oldstat;
- bool blockend;
+ bool last_blockend;
bool dataend;
/* pio stuff */
--
1.7.3.2
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