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spi: qup: Setup DMA mode correctly 

To operate in DMA mode, the buffer should be aligned and
the size of the transfer should be a multiple of block size
(for v1). And the no. of words being transferred should
be programmed in the count registers appropriately.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
hifive-unleashed-5.1
Varadarajan Narayanan 2017-07-28 12:22:49 +05:30 committed by Mark Brown
parent b702b9fb39
commit 32ecab999f
1 changed files with 56 additions and 64 deletions
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120
drivers/spi/spi-qup.c
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@ -149,11 +149,18 @@ struct spi_qup {
int rx_bytes;
int qup_v1;
int use_dma;
int mode;
struct dma_slave_config rx_conf;
struct dma_slave_config tx_conf;
};
static inline bool spi_qup_is_dma_xfer(int mode)
{
if (mode == QUP_IO_M_MODE_DMOV || mode == QUP_IO_M_MODE_BAM)
return true;
return false;
}
static inline bool spi_qup_is_valid_state(struct spi_qup *controller)
{
@ -424,7 +431,7 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id)
error = -EIO;
}
if (!controller->use_dma) {
if (!spi_qup_is_dma_xfer(controller->mode)) {
if (opflags & QUP_OP_IN_SERVICE_FLAG)
spi_qup_fifo_read(controller, xfer);
@ -443,34 +450,11 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id)
return IRQ_HANDLED;
}
static u32
spi_qup_get_mode(struct spi_master *master, struct spi_transfer *xfer)
{
struct spi_qup *qup = spi_master_get_devdata(master);
u32 mode;
qup->w_size = 4;
if (xfer->bits_per_word <= 8)
qup->w_size = 1;
else if (xfer->bits_per_word <= 16)
qup->w_size = 2;
qup->n_words = xfer->len / qup->w_size;
if (qup->n_words <= (qup->in_fifo_sz / sizeof(u32)))
mode = QUP_IO_M_MODE_FIFO;
else
mode = QUP_IO_M_MODE_BLOCK;
return mode;
}
/* set clock freq ... bits per word */
static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
{
struct spi_qup *controller = spi_master_get_devdata(spi->master);
u32 config, iomode, mode, control;
u32 config, iomode, control;
int ret, n_words;
if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) {
@ -491,25 +475,30 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
return -EIO;
}
mode = spi_qup_get_mode(spi->master, xfer);
controller->w_size = DIV_ROUND_UP(xfer->bits_per_word, 8);
controller->n_words = xfer->len / controller->w_size;
n_words = controller->n_words;
if (mode == QUP_IO_M_MODE_FIFO) {
if (n_words <= (controller->in_fifo_sz / sizeof(u32))) {
controller->mode = QUP_IO_M_MODE_FIFO;
writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT);
writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT);
/* must be zero for FIFO */
writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT);
writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
} else if (!controller->use_dma) {
} else if (spi->master->can_dma &&
spi->master->can_dma(spi->master, spi, xfer) &&
spi->master->cur_msg_mapped) {
controller->mode = QUP_IO_M_MODE_BAM;
writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
/* must be zero for BLOCK and BAM */
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
} else {
mode = QUP_IO_M_MODE_BAM;
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
if (!controller->qup_v1) {
void __iomem *input_cnt;
@ -528,19 +517,28 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
}
} else {
controller->mode = QUP_IO_M_MODE_BLOCK;
writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
/* must be zero for BLOCK and BAM */
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
}
iomode = readl_relaxed(controller->base + QUP_IO_M_MODES);
/* Set input and output transfer mode */
iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK);
if (!controller->use_dma)
if (!spi_qup_is_dma_xfer(controller->mode))
iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN);
else
iomode |= QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN;
iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT);
iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT);
iomode |= (controller->mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT);
iomode |= (controller->mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT);
writel_relaxed(iomode, controller->base + QUP_IO_M_MODES);
@ -581,7 +579,7 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
config |= xfer->bits_per_word - 1;
config |= QUP_CONFIG_SPI_MODE;
if (controller->use_dma) {
if (spi_qup_is_dma_xfer(controller->mode)) {
if (!xfer->tx_buf)
config |= QUP_CONFIG_NO_OUTPUT;
if (!xfer->rx_buf)
@ -599,7 +597,7 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
* status change in BAM mode
*/
if (mode == QUP_IO_M_MODE_BAM)
if (spi_qup_is_dma_xfer(controller->mode))
mask = QUP_OP_IN_SERVICE_FLAG | QUP_OP_OUT_SERVICE_FLAG;
writel_relaxed(mask, controller->base + QUP_OPERATIONAL_MASK);
@ -633,7 +631,7 @@ static int spi_qup_transfer_one(struct spi_master *master,
controller->tx_bytes = 0;
spin_unlock_irqrestore(&controller->lock, flags);
if (controller->use_dma)
if (spi_qup_is_dma_xfer(controller->mode))
ret = spi_qup_do_dma(master, xfer);
else
ret = spi_qup_do_pio(master, xfer);
@ -641,14 +639,6 @@ static int spi_qup_transfer_one(struct spi_master *master,
if (ret)
goto exit;
if (spi_qup_set_state(controller, QUP_STATE_RUN)) {
dev_warn(controller->dev, "cannot set EXECUTE state\n");
goto exit;
}
if (!wait_for_completion_timeout(&controller->done, timeout))
ret = -ETIMEDOUT;
exit:
spi_qup_set_state(controller, QUP_STATE_RESET);
spin_lock_irqsave(&controller->lock, flags);
@ -657,7 +647,7 @@ exit:
ret = controller->error;
spin_unlock_irqrestore(&controller->lock, flags);
if (ret && controller->use_dma)
if (ret && spi_qup_is_dma_xfer(controller->mode))
spi_qup_dma_terminate(master, xfer);
return ret;
@ -668,26 +658,28 @@ static bool spi_qup_can_dma(struct spi_master *master, struct spi_device *spi,
{
struct spi_qup *qup = spi_master_get_devdata(master);
size_t dma_align = dma_get_cache_alignment();
u32 mode;
int n_words;
qup->use_dma = 0;
if (xfer->rx_buf) {
if (!IS_ALIGNED((size_t)xfer->rx_buf, dma_align) ||
IS_ERR_OR_NULL(master->dma_rx))
return false;
if (qup->qup_v1 && (xfer->len % qup->in_blk_sz))
return false;
}
if (xfer->rx_buf && (xfer->len % qup->in_blk_sz ||
IS_ERR_OR_NULL(master->dma_rx) ||
!IS_ALIGNED((size_t)xfer->rx_buf, dma_align)))
if (xfer->tx_buf) {
if (!IS_ALIGNED((size_t)xfer->tx_buf, dma_align) ||
IS_ERR_OR_NULL(master->dma_tx))
return false;
if (qup->qup_v1 && (xfer->len % qup->out_blk_sz))
return false;
}
n_words = xfer->len / DIV_ROUND_UP(xfer->bits_per_word, 8);
if (n_words <= (qup->in_fifo_sz / sizeof(u32)))
return false;
if (xfer->tx_buf && (xfer->len % qup->out_blk_sz ||
IS_ERR_OR_NULL(master->dma_tx) ||
!IS_ALIGNED((size_t)xfer->tx_buf, dma_align)))
return false;
mode = spi_qup_get_mode(master, xfer);
if (mode == QUP_IO_M_MODE_FIFO)
return false;
qup->use_dma = 1;
return true;
}