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Subject[PATCH 2/2] spi_topcliff_pch: DMA support
Date
This patch enables this SPI driver works with DMA mode.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
---
drivers/spi/spi_topcliff_pch.c | 612 ++++++++++++++++++++++++++++++++--------
1 files changed, 492 insertions(+), 120 deletions(-)
diff --git a/drivers/spi/spi_topcliff_pch.c b/drivers/spi/spi_topcliff_pch.c
index 88bd472..f543ff6 100644
--- a/drivers/spi/spi_topcliff_pch.c
+++ b/drivers/spi/spi_topcliff_pch.c
@@ -28,6 +28,9 @@
#include <linux/device.h>
#include <linux/platform_device.h>

+#include <linux/dmaengine.h>
+#include <linux/pch_dma.h>
+
/* Register offsets */
#define PCH_SPCR 0x00 /* SPI control register */
#define PCH_SPBRR 0x04 /* SPI baud rate register */
@@ -36,7 +39,7 @@
#define PCH_SPDRR 0x10 /* SPI read data register */
#define PCH_SSNXCR 0x18 /* SSN Expand Control Register */
#define PCH_SRST 0x1C /* SPI reset register */
-#define PCH_SPI_ADDRESS_SIZE 0x20
+#define PCH_ADDRESS_SIZE 0x20

#define PCH_SPSR_TFD 0x000007C0
#define PCH_SPSR_RFD 0x0000F800
@@ -54,8 +57,6 @@
#define STATUS_EXITING 2
#define PCH_SLEEP_TIME 10

-#define PCH_ADDRESS_SIZE 0x20
-
#define SSN_LOW 0x02U
#define SSN_NO_CONTROL 0x00U
#define PCH_MAX_CS 0xFF
@@ -75,6 +76,7 @@
#define SPSR_TFI_BIT (1 << 0)
#define SPSR_RFI_BIT (1 << 1)
#define SPSR_FI_BIT (1 << 2)
+#define SPSR_ORF_BIT (1 << 3)
#define SPBRR_SIZE_BIT (1 << 10)

#define PCH_ALL (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
@@ -83,10 +85,9 @@
#define SPCR_RFIC_FIELD 20
#define SPCR_TFIC_FIELD 16

-#define SPSR_INT_BITS 0x1F
-#define MASK_SPBRR_SPBR_BITS (~((1 << 10) - 1))
-#define MASK_RFIC_SPCR_BITS (~(0xf << 20))
-#define MASK_TFIC_SPCR_BITS (~(0xf000f << 12))
+#define MASK_SPBRR_SPBR_BITS ((1 << 10) - 1)
+#define MASK_RFIC_SPCR_BITS (0xf << SPCR_RFIC_FIELD)
+#define MASK_TFIC_SPCR_BITS (0xf << SPCR_TFIC_FIELD)

#define PCH_CLOCK_HZ 50000000
#define PCH_MAX_SPBR 1023
@@ -102,6 +103,28 @@
*/
#define PCH_SPI_MAX_DEV 2

+#define PCH_BUF_SIZE 4096
+#define PCH_DMA_TRANS_SIZE 12
+
+static int use_dma = 1;
+
+struct pch_spi_dma_ctrl {
+ struct dma_async_tx_descriptor *desc_tx;
+ struct dma_async_tx_descriptor *desc_rx;
+ struct pch_dma_slave param_tx;
+ struct pch_dma_slave param_rx;
+ struct dma_chan *chan_tx;
+ struct dma_chan *chan_rx;
+ struct scatterlist *sg_tx_p;
+ struct scatterlist *sg_rx_p;
+ struct scatterlist sg_tx;
+ struct scatterlist sg_rx;
+ int nent;
+ void *tx_buf_virt;
+ void *rx_buf_virt;
+ dma_addr_t tx_buf_dma;
+ dma_addr_t rx_buf_dma;
+};
/**
* struct pch_spi_data - Holds the SPI channel specific details
* @io_remap_addr: The remapped PCI base address
@@ -140,6 +163,7 @@
*/
struct pch_spi_data {
void __iomem *io_remap_addr;
+ unsigned long io_base_addr;
struct spi_master *master;
struct work_struct work;
struct workqueue_struct *wk;
@@ -162,6 +186,8 @@ struct pch_spi_data {
struct pch_spi_board_data *board_dat;
struct platform_device *plat_dev;
int ch;
+ struct pch_spi_dma_ctrl dma;
+ int use_dma;
u8 irq_reg_sts;
};

@@ -273,10 +299,10 @@ static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */

/* reset rx threshold */
- reg_spcr_val &= MASK_RFIC_SPCR_BITS;
+ reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
- iowrite32(((reg_spcr_val) &= (~(SPCR_RFIE_BIT))),
- (io_remap_addr + PCH_SPCR));
+
+ iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
}

/* update counts */
@@ -287,12 +313,15 @@ static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,

/* if transfer complete interrupt */
if (reg_spsr_val & SPSR_FI_BIT) {
- /* disable FI & RFI interrupts */
- pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
- SPCR_FIE_BIT | SPCR_RFIE_BIT);
+ if (tx_index < bpw_len)
+ dev_err(&data->master->dev,
+ "%s : Transfer is not completed", __func__);
+ /* disable interrupts */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);

/* transfer is completed;inform pch_spi_process_messages */
data->transfer_complete = true;
+ data->transfer_active = false;
wake_up(&data->wait);
}
}
@@ -316,11 +345,16 @@ static irqreturn_t pch_spi_handler(int irq, void *dev_id)
"%s returning due to suspend\n", __func__);
return IRQ_NONE;
}
+ if (data->use_dma)
+ return IRQ_NONE;

io_remap_addr = data->io_remap_addr;
spsr = io_remap_addr + PCH_SPSR;
reg_spsr_val = ioread32(spsr);

+ if (reg_spsr_val & SPSR_ORF_BIT)
+ dev_err(&board_dat->pdev->dev, "%s Over run error", __func__);
+
/* Check if the interrupt is for SPI device */
if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
@@ -346,7 +380,7 @@ static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
if (n_spbr > PCH_MAX_SPBR)
n_spbr = PCH_MAX_SPBR;

- pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, ~MASK_SPBRR_SPBR_BITS);
+ pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
}

/**
@@ -454,26 +488,27 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
dev_dbg(&pspi->dev, "%s Transfer List not empty. "
"Transfer Speed is set.\n", __func__);

+ spin_lock_irqsave(&data->lock, flags);
/* validate Tx/Rx buffers and Transfer length */
list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
if (!transfer->tx_buf && !transfer->rx_buf) {
dev_err(&pspi->dev,
"%s Tx and Rx buffer NULL\n", __func__);
retval = -EINVAL;
- goto err_out;
+ goto err_return_spinlock;
}

if (!transfer->len) {
dev_err(&pspi->dev, "%s Transfer length invalid\n",
__func__);
retval = -EINVAL;
- goto err_out;
+ goto err_return_spinlock;
}

dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
" valid\n", __func__);

- /* if baud rate hs been specified validate the same */
+ /* if baud rate has been specified validate the same */
if (transfer->speed_hz > PCH_MAX_BAUDRATE)
transfer->speed_hz = PCH_MAX_BAUDRATE;

@@ -484,25 +519,24 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
retval = -EINVAL;
dev_err(&pspi->dev,
"%s Invalid bits per word\n", __func__);
- goto err_out;
+ goto err_return_spinlock;
}
}
}
-
- spin_lock_irqsave(&data->lock, flags);
+ spin_unlock_irqrestore(&data->lock, flags);

/* We won't process any messages if we have been asked to terminate */
if (data->status == STATUS_EXITING) {
dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
retval = -ESHUTDOWN;
- goto err_return_spinlock;
+ goto err_out;
}

/* If suspended ,return -EINVAL */
if (data->board_dat->suspend_sts) {
dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
retval = -EINVAL;
- goto err_return_spinlock;
+ goto err_out;
}

/* set status of message */
@@ -510,9 +544,11 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);

pmsg->status = -EINPROGRESS;
-
+ spin_lock_irqsave(&data->lock, flags);
/* add message to queue */
list_add_tail(&pmsg->queue, &data->queue);
+ spin_unlock_irqrestore(&data->lock, flags);
+
dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);

/* schedule work queue to run */
@@ -521,11 +557,13 @@ static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)

retval = 0;

-err_return_spinlock:
- spin_unlock_irqrestore(&data->lock, flags);
err_out:
dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
return retval;
+err_return_spinlock:
+ dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
+ spin_unlock_irqrestore(&data->lock, flags);
+ return retval;
}

static inline void pch_spi_select_chip(struct pch_spi_data *data,
@@ -546,8 +584,7 @@ static inline void pch_spi_select_chip(struct pch_spi_data *data,
pch_spi_setup_transfer(pspi);
}

-static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
- struct spi_message **ppmsg)
+static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
{
int size;
u32 n_writes;
@@ -556,8 +593,6 @@ static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
const u8 *tx_buf;
const u16 *tx_sbuf;

- pmsg = *ppmsg;
-
/* set baud rate if needed */
if (data->cur_trans->speed_hz) {
dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
@@ -566,8 +601,8 @@ static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,

/* set bits per word if needed */
if (data->cur_trans->bits_per_word &&
- (data->current_msg->spi->bits_per_word !=\
- data->cur_trans->bits_per_word)) {
+ (data->current_msg->spi->bits_per_word !=\
+ data->cur_trans->bits_per_word)) {
dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
pch_spi_set_bits_per_word(data->master,
data->cur_trans->bits_per_word);
@@ -641,9 +676,9 @@ static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
data->transfer_active = true;
}

-static void pch_spi_nomore_transfer(struct pch_spi_data *data,
- struct spi_message *pmsg)
+static void pch_spi_nomore_transfer(struct pch_spi_data *data)
{
+ struct spi_message *pmsg;
dev_dbg(&data->master->dev, "%s called\n", __func__);
/* Invoke complete callback
* [To the spi core..indicating end of transfer] */
@@ -694,30 +729,21 @@ static void pch_spi_nomore_transfer(struct pch_spi_data *data,

static void pch_spi_set_ir(struct pch_spi_data *data)
{
- /* enable interrupts */
- if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
+ /* enable interrupts, set threshold, enable SPI */
+ if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
/* set receive threshold to PCH_RX_THOLD */
pch_spi_setclr_reg(data->master, PCH_SPCR,
- PCH_RX_THOLD << SPCR_RFIC_FIELD,
- ~MASK_RFIC_SPCR_BITS);
- /* enable FI and RFI interrupts */
- pch_spi_setclr_reg(data->master, PCH_SPCR,
- SPCR_RFIE_BIT | SPCR_FIE_BIT, 0);
- } else {
+ PCH_RX_THOLD << SPCR_RFIC_FIELD |
+ SPCR_FIE_BIT | SPCR_RFIE_BIT |
+ SPCR_ORIE_BIT | SPCR_SPE_BIT,
+ MASK_RFIC_SPCR_BITS | PCH_ALL);
+ else
/* set receive threshold to maximum */
pch_spi_setclr_reg(data->master, PCH_SPCR,
- PCH_RX_THOLD_MAX << SPCR_TFIC_FIELD,
- ~MASK_TFIC_SPCR_BITS);
- /* enable FI interrupt */
- pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_FIE_BIT, 0);
- }
-
- dev_dbg(&data->master->dev,
- "%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
-
- /* SPI set enable */
- pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, SPCR_SPE_BIT,
- 0);
+ PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
+ SPCR_FIE_BIT | SPCR_ORIE_BIT |
+ SPCR_SPE_BIT,
+ MASK_RFIC_SPCR_BITS | PCH_ALL);

/* Wait until the transfer completes; go to sleep after
initiating the transfer. */
@@ -730,15 +756,13 @@ static void pch_spi_set_ir(struct pch_spi_data *data)
dev_dbg(&data->master->dev,
"%s:no more control over SSN-writing 0 to SSNXCR.", __func__);

- data->transfer_active = false;
- dev_dbg(&data->master->dev,
- "%s set data->transfer_active = false\n", __func__);
-
/* clear all interrupts */
pch_spi_writereg(data->master, PCH_SPSR,
pch_spi_readreg(data->master, PCH_SPSR));
- /* disable interrupts */
- pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
+ /* Disable interrupts and SPI transfer */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
+ /* clear FIFO */
+ pch_spi_clear_fifo(data->master);
}

static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
@@ -762,6 +786,328 @@ static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
}
}

+static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
+{
+ int j;
+ u8 *rx_buf;
+ u16 *rx_sbuf;
+ const u8 *rx_dma_buf;
+ const u16 *rx_dma_sbuf;
+
+ /* copy Rx Data */
+ if (!data->cur_trans->rx_buf)
+ return;
+
+ if (bpw == 8) {
+ rx_buf = data->cur_trans->rx_buf;
+ rx_dma_buf = data->dma.rx_buf_virt;
+ for (j = 0; j < data->bpw_len; j++)
+ *rx_buf++ = *rx_dma_buf++ & 0xFF;
+ } else {
+ rx_sbuf = data->cur_trans->rx_buf;
+ rx_dma_sbuf = data->dma.rx_buf_virt;
+ for (j = 0; j < data->bpw_len; j++)
+ *rx_sbuf++ = *rx_dma_sbuf++;
+ }
+}
+
+static void pch_spi_start_transfer(struct pch_spi_data *data)
+{
+ struct pch_spi_dma_ctrl *dma;
+ unsigned long flags;
+
+ dma = &data->dma;
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ /* disable interrupts, SPI set enable */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ /* Wait until the transfer completes; go to sleep after
+ initiating the transfer. */
+ dev_dbg(&data->master->dev,
+ "%s:waiting for transfer to get over\n", __func__);
+ wait_event_interruptible(data->wait, data->transfer_complete);
+
+ dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
+ DMA_FROM_DEVICE);
+ async_tx_ack(dma->desc_rx);
+ async_tx_ack(dma->desc_tx);
+ kfree(dma->sg_tx_p);
+ kfree(dma->sg_rx_p);
+
+ spin_lock_irqsave(&data->lock, flags);
+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
+ dev_dbg(&data->master->dev,
+ "%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
+
+ /* clear fifo threshold, disable interrupts, disable SPI transfer */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
+ MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
+ SPCR_SPE_BIT);
+ /* clear all interrupts */
+ pch_spi_writereg(data->master, PCH_SPSR,
+ pch_spi_readreg(data->master, PCH_SPSR));
+ /* clear FIFO */
+ pch_spi_clear_fifo(data->master);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static void pch_dma_rx_complete(void *arg)
+{
+ struct pch_spi_data *data = arg;
+
+ /* transfer is completed;inform pch_spi_process_messages_dma */
+ data->transfer_complete = true;
+ wake_up_interruptible(&data->wait);
+}
+
+static bool pch_spi_filter(struct dma_chan *chan, void *slave)
+{
+ struct pch_dma_slave *param = slave;
+
+ if ((chan->chan_id == param->chan_id) &&
+ (param->dma_dev == chan->device->dev)) {
+ chan->private = param;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
+{
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+ struct pci_dev *dma_dev;
+ struct pch_dma_slave *param;
+ struct pch_spi_dma_ctrl *dma;
+ unsigned int width;
+
+ if (bpw == 8)
+ width = PCH_DMA_WIDTH_1_BYTE;
+ else
+ width = PCH_DMA_WIDTH_2_BYTES;
+
+ dma = &data->dma;
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ /* Get DMA's dev information */
+ dma_dev = pci_get_bus_and_slot(2, PCI_DEVFN(12, 0));
+
+ /* Set Tx DMA */
+ param = &dma->param_tx;
+ param->dma_dev = &dma_dev->dev;
+ param->chan_id = data->master->bus_num * 2; /* Tx = 0, 2 */
+ param->tx_reg = data->io_base_addr + PCH_SPDWR;
+ param->width = width;
+ chan = dma_request_channel(mask, pch_spi_filter, param);
+ if (!chan) {
+ dev_err(&data->master->dev,
+ "ERROR: dma_request_channel FAILS(Tx)\n");
+ data->use_dma = 0;
+ return;
+ }
+ dma->chan_tx = chan;
+
+ /* Set Rx DMA */
+ param = &dma->param_rx;
+ param->dma_dev = &dma_dev->dev;
+ param->chan_id = data->master->bus_num * 2 + 1; /* Rx = Tx + 1 */
+ param->rx_reg = data->io_base_addr + PCH_SPDRR;
+ param->width = width;
+ chan = dma_request_channel(mask, pch_spi_filter, param);
+ if (!chan) {
+ dev_err(&data->master->dev,
+ "ERROR: dma_request_channel FAILS(Rx)\n");
+ dma_release_channel(dma->chan_tx);
+ dma->chan_tx = NULL;
+ data->use_dma = 0;
+ return;
+ }
+ dma->chan_rx = chan;
+}
+
+static void pch_spi_release_dma(struct pch_spi_data *data)
+{
+ struct pch_spi_dma_ctrl *dma;
+
+ dma = &data->dma;
+ if (dma->chan_tx) {
+ dma_release_channel(dma->chan_tx);
+ dma->chan_tx = NULL;
+ }
+ if (dma->chan_rx) {
+ dma_release_channel(dma->chan_rx);
+ dma->chan_rx = NULL;
+ }
+ return;
+}
+
+static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
+{
+ const u8 *tx_buf;
+ const u16 *tx_sbuf;
+ u8 *tx_dma_buf;
+ u16 *tx_dma_sbuf;
+ struct scatterlist *sg;
+ struct dma_async_tx_descriptor *desc_tx;
+ struct dma_async_tx_descriptor *desc_rx;
+ int num;
+ int i;
+ int size;
+ int rem;
+ unsigned long flags;
+ struct pch_spi_dma_ctrl *dma;
+
+ dma = &data->dma;
+
+ /* set baud rate if needed */
+ if (data->cur_trans->speed_hz) {
+ dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
+ spin_lock_irqsave(&data->lock, flags);
+ pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
+ spin_unlock_irqrestore(&data->lock, flags);
+ }
+
+ /* set bits per word if needed */
+ if (data->cur_trans->bits_per_word &&
+ (data->current_msg->spi->bits_per_word !=
+ data->cur_trans->bits_per_word)) {
+ dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
+ spin_lock_irqsave(&data->lock, flags);
+ pch_spi_set_bits_per_word(data->master,
+ data->cur_trans->bits_per_word);
+ spin_unlock_irqrestore(&data->lock, flags);
+ *bpw = data->cur_trans->bits_per_word;
+ } else {
+ *bpw = data->current_msg->spi->bits_per_word;
+ }
+ data->bpw_len = data->cur_trans->len / (*bpw / 8);
+
+ /* copy Tx Data */
+ if (data->cur_trans->tx_buf != NULL) {
+ if (*bpw == 8) {
+ tx_buf = data->cur_trans->tx_buf;
+ tx_dma_buf = dma->tx_buf_virt;
+ for (i = 0; i < data->bpw_len; i++)
+ *tx_dma_buf++ = *tx_buf++;
+ } else {
+ tx_sbuf = data->cur_trans->tx_buf;
+ tx_dma_sbuf = dma->tx_buf_virt;
+ for (i = 0; i < data->bpw_len; i++)
+ *tx_dma_sbuf++ = *tx_sbuf++;
+ }
+ }
+ if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
+ num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+ size = PCH_DMA_TRANS_SIZE;
+ rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
+ } else {
+ num = 1;
+ size = data->bpw_len;
+ rem = data->bpw_len;
+ }
+ dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
+ __func__, num, size, rem);
+ spin_lock_irqsave(&data->lock, flags);
+
+ /* set receive fifo threshold and transmit fifo threshold */
+ pch_spi_setclr_reg(data->master, PCH_SPCR,
+ ((size - 1) << SPCR_RFIC_FIELD) |
+ ((PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE) <<
+ SPCR_TFIC_FIELD),
+ MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ /* RX */
+ dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
+ sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
+ /* offset, length setting */
+ sg = dma->sg_rx_p;
+ for (i = 0; i < num; i++, sg++) {
+ if (i == 0) {
+ sg->offset = 0;
+ sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
+ sg->offset);
+ sg_dma_len(sg) = rem;
+ } else {
+ sg->offset = rem + size * (i - 1);
+ sg->offset = sg->offset * (*bpw / 8);
+ sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
+ sg->offset);
+ sg_dma_len(sg) = size;
+ }
+ sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
+ }
+ sg = dma->sg_rx_p;
+ desc_rx = dma->chan_rx->device->device_prep_slave_sg(dma->chan_rx, sg,
+ num, DMA_FROM_DEVICE,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc_rx) {
+ dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
+ __func__);
+ return;
+ }
+ dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
+ desc_rx->callback = pch_dma_rx_complete;
+ desc_rx->callback_param = data;
+ dma->nent = num;
+ dma->desc_rx = desc_rx;
+
+ /* TX */
+ dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
+ sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
+ /* offset, length setting */
+ sg = dma->sg_tx_p;
+ for (i = 0; i < num; i++, sg++) {
+ if (i == 0) {
+ sg->offset = 0;
+ sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
+ sg->offset);
+ sg_dma_len(sg) = rem;
+ } else {
+ sg->offset = rem + size * (i - 1);
+ sg->offset = sg->offset * (*bpw / 8);
+ sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
+ sg->offset);
+ sg_dma_len(sg) = size;
+ }
+ sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
+ }
+ sg = dma->sg_tx_p;
+ desc_tx = dma->chan_tx->device->device_prep_slave_sg(dma->chan_tx,
+ sg, num, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc_tx) {
+ dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
+ __func__);
+ return;
+ }
+ dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
+ desc_tx->callback = NULL;
+ desc_tx->callback_param = data;
+ dma->nent = num;
+ dma->desc_tx = desc_tx;
+
+ dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
+ "0x2 to SSNXCR\n", __func__);
+
+ spin_lock_irqsave(&data->lock, flags);
+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
+ desc_rx->tx_submit(desc_rx);
+ desc_tx->tx_submit(desc_tx);
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ /* reset transfer complete flag */
+ data->transfer_complete = false;
+}
+
static void pch_spi_process_messages(struct work_struct *pwork)
{
struct spi_message *pmsg;
@@ -772,30 +1118,23 @@ static void pch_spi_process_messages(struct work_struct *pwork)
dev_dbg(&data->master->dev, "%s data initialized\n", __func__);

spin_lock(&data->lock);
-
/* check if suspend has been initiated;if yes flush queue */
if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
- dev_dbg(&data->master->dev,
- "%s suspend/remove initiated,flushing queue\n",
- __func__);
-
+ dev_dbg(&data->master->dev, "%s suspend/remove initiated,"
+ "flushing queue\n", __func__);
list_for_each_entry(pmsg, data->queue.next, queue) {
pmsg->status = -EIO;
-
if (pmsg->complete != 0) {
spin_unlock(&data->lock);
pmsg->complete(pmsg->context);
spin_lock(&data->lock);
}
-
/* delete from queue */
list_del_init(&pmsg->queue);
}
-
spin_unlock(&data->lock);
return;
}
-
data->bcurrent_msg_processing = true;
dev_dbg(&data->master->dev,
"%s Set data->bcurrent_msg_processing= true\n", __func__);
@@ -803,62 +1142,47 @@ static void pch_spi_process_messages(struct work_struct *pwork)
/* Get the message from the queue and delete it from there. */
data->current_msg = list_entry(data->queue.next, struct spi_message,
queue);
-
list_del_init(&data->current_msg->queue);
-
data->current_msg->status = 0;
-
pch_spi_select_chip(data, data->current_msg->spi);
-
spin_unlock(&data->lock);

+ if (data->use_dma)
+ pch_spi_request_dma(data,
+ data->current_msg->spi->bits_per_word);
do {
/* If we are already processing a message get the next
transfer structure from the message otherwise retrieve
the 1st transfer request from the message. */
spin_lock(&data->lock);
-
if (data->cur_trans == NULL) {
data->cur_trans =
- list_entry(data->current_msg->transfers.
- next, struct spi_transfer,
- transfer_list);
- dev_dbg(&data->master->dev,
- "%s :Getting 1st transfer message\n", __func__);
+ list_entry(data->current_msg->transfers.next,
+ struct spi_transfer, transfer_list);
+ dev_dbg(&data->master->dev, "%s "
+ ":Getting 1st transfer message\n", __func__);
} else {
data->cur_trans =
- list_entry(data->cur_trans->transfer_list.next,
- struct spi_transfer,
- transfer_list);
- dev_dbg(&data->master->dev,
- "%s :Getting next transfer message\n",
- __func__);
+ list_entry(data->cur_trans->transfer_list.next,
+ struct spi_transfer, transfer_list);
+ dev_dbg(&data->master->dev, "%s "
+ ":Getting next transfer message\n", __func__);
}
-
spin_unlock(&data->lock);

- pch_spi_set_tx(data, &bpw, &pmsg);
-
- /* Control interrupt*/
- pch_spi_set_ir(data);
-
- /* Disable SPI transfer */
- pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, 0,
- SPCR_SPE_BIT);
-
- /* clear FIFO */
- pch_spi_clear_fifo(data->master);
-
- /* copy Rx Data */
- pch_spi_copy_rx_data(data, bpw);
-
- /* free memory */
- kfree(data->pkt_rx_buff);
- data->pkt_rx_buff = NULL;
-
- kfree(data->pkt_tx_buff);
- data->pkt_tx_buff = NULL;
-
+ if (data->use_dma) {
+ pch_spi_handle_dma(data, &bpw);
+ pch_spi_start_transfer(data);
+ pch_spi_copy_rx_data_for_dma(data, bpw);
+ } else {
+ pch_spi_set_tx(data, &bpw);
+ pch_spi_set_ir(data);
+ pch_spi_copy_rx_data(data, bpw);
+ kfree(data->pkt_rx_buff);
+ data->pkt_rx_buff = NULL;
+ kfree(data->pkt_tx_buff);
+ data->pkt_tx_buff = NULL;
+ }
/* increment message count */
data->current_msg->actual_length += data->cur_trans->len;

@@ -875,16 +1199,17 @@ static void pch_spi_process_messages(struct work_struct *pwork)
}

spin_lock(&data->lock);
-
/* No more transfer in this message. */
if ((data->cur_trans->transfer_list.next) ==
&(data->current_msg->transfers)) {
- pch_spi_nomore_transfer(data, pmsg);
+ pch_spi_nomore_transfer(data);
}
-
spin_unlock(&data->lock);

} while (data->cur_trans != NULL);
+
+ if (data->use_dma)
+ pch_spi_release_dma(data);
}

static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
@@ -911,6 +1236,7 @@ static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,

/* create workqueue */
data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
+
if (!data->wk) {
dev_err(&board_dat->pdev->dev,
"%s create_singlet hread_workqueue failed\n", __func__);
@@ -937,6 +1263,35 @@ err_return:
return retval;
}

+static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
+ struct pch_spi_data *data)
+{
+ struct pch_spi_dma_ctrl *dma;
+
+ dma = &data->dma;
+ if (dma->tx_buf_dma)
+ dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
+ dma->tx_buf_virt, dma->tx_buf_dma);
+ if (dma->rx_buf_dma)
+ dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
+ dma->rx_buf_virt, dma->rx_buf_dma);
+ return;
+}
+
+static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
+ struct pch_spi_data *data)
+{
+ struct pch_spi_dma_ctrl *dma;
+
+ dma = &data->dma;
+ /* Get Consistent memory for Tx DMA */
+ dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
+ PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
+ /* Get Consistent memory for Rx DMA */
+ dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
+ PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
+}
+
static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
{
int ret;
@@ -944,6 +1299,8 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
struct pch_spi_data *data;

+ dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
+
master = spi_alloc_master(&board_dat->pdev->dev,
sizeof(struct pch_spi_data));
if (!master) {
@@ -957,9 +1314,11 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)

platform_set_drvdata(plat_dev, data);

- /* baseaddress + 0x20(offset) */
+ /* baseaddress + address offset) */
+ data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
+ PCH_ADDRESS_SIZE * plat_dev->id;
data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0) +
- 0x20 * plat_dev->id;
+ PCH_ADDRESS_SIZE * plat_dev->id;
if (!data->io_remap_addr) {
dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
ret = -ENOMEM;
@@ -980,6 +1339,7 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
data->n_curnt_chip = 255;
data->status = STATUS_RUNNING;
data->ch = plat_dev->id;
+ data->use_dma = use_dma;

INIT_LIST_HEAD(&data->queue);
spin_lock_init(&data->lock);
@@ -1010,6 +1370,11 @@ static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
goto err_spi_register_master;
}

+ if (use_dma) {
+ dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
+ pch_alloc_dma_buf(board_dat, data);
+ }
+
return 0;

err_spi_register_master:
@@ -1029,22 +1394,27 @@ static int __devexit pch_spi_pd_remove(struct platform_device *plat_dev)
struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
struct pch_spi_data *data = platform_get_drvdata(plat_dev);
int count;
+ unsigned long flags;

dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
__func__, plat_dev->id, board_dat->pdev->irq);
+
+ if (use_dma)
+ pch_free_dma_buf(board_dat, data);
+
/* check for any pending messages; no action is taken if the queue
* is still full; but at least we tried. Unload anyway */
count = 500;
- spin_lock(&data->lock);
+ spin_lock_irqsave(&data->lock, flags);
data->status = STATUS_EXITING;
while ((list_empty(&data->queue) == 0) && --count) {
dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
__func__);
- spin_unlock(&data->lock);
+ spin_unlock_irqrestore(&data->lock, flags);
msleep(PCH_SLEEP_TIME);
- spin_lock(&data->lock);
+ spin_lock_irqsave(&data->lock, flags);
}
- spin_unlock(&data->lock);
+ spin_unlock_irqrestore(&data->lock, flags);

pch_spi_free_resources(board_dat, data);
/* disable interrupts & free IRQ */
@@ -1081,8 +1451,8 @@ static int pch_spi_pd_suspend(struct platform_device *pd_dev,
/* check if the current message is processed:
Only after thats done the transfer will be suspended */
count = 255;
- while ((--count) > 0)
- if (!(data->bcurrent_msg_processing)) {
+ while ((--count) > 0) {
+ if (!(data->bcurrent_msg_processing))
break;
msleep(PCH_SLEEP_TIME);
}
@@ -1123,7 +1493,6 @@ static int pch_spi_pd_resume(struct platform_device *pd_dev)
"%s request_irq failed\n", __func__);
return retval;
}
-
/* reset PCH SPI h/w */
pch_spi_reset(data->master);
pch_spi_set_master_mode(data->master);
@@ -1213,7 +1582,6 @@ static int __devinit pch_spi_probe(struct pci_dev *pdev,
}

pci_set_drvdata(pdev, pd_dev_save);
-
return 0;

err_platform_device:
@@ -1326,5 +1694,9 @@ static void __exit pch_spi_exit(void)
}
module_exit(pch_spi_exit);

+module_param(use_dma, int, 0644);
+MODULE_PARM_DESC(use_dma,
+ "to use DMA for data transfers pass 1 else 0; default 1");
+
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Intel EG20T PCH/OKI SEMICONDUCTOR ML7213 IOH SPI Driver");
--
1.7.4


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  Last update: 2011-04-27 04:25    [from the cache]
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