[FYI 1/4] mmci: fixup broken_blockend variant patch

From: Per Forlin
Date: Wed Jan 12 2011 - 13:20:30 EST


From: Ulf Hansson <ulf.hansson@xxxxxxxxxxxxxx>

NOT to be mainlined, only sets the base for the double
buffer example implementation. The DMA implemenation for
MMCI is under development.

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, this is faster anyway.

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.
---
drivers/mmc/host/mmci.c | 45 ++++++++++++++++++++++-----------------------
drivers/mmc/host/mmci.h | 4 ++--
2 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 5630228..aafede4 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;

/*
@@ -337,7 +340,7 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
*
* 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
+ * so for this case we use the flags "last_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
@@ -353,7 +356,8 @@ 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)
@@ -364,11 +368,12 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
* 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 +775,6 @@ 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 +955,7 @@ 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 */
--
1.7.1

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