diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-topcliff-pch.c | 594 |
1 files changed, 488 insertions, 106 deletions
diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c index be84e3a36406..1b8030bc24b7 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); } } @@ -316,12 +345,17 @@ 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); @@ -347,7 +381,7 @@ 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); } /** @@ -456,26 +490,27 @@ 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; @@ -486,25 +521,24 @@ 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 */ @@ -512,9 +546,11 @@ 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 */ @@ -523,11 +559,13 @@ 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, @@ -548,8 +586,7 @@ 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; @@ -558,8 +595,6 @@ 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__); @@ -642,10 +677,9 @@ 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] */ @@ -696,29 +730,21 @@ 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. */ @@ -731,15 +757,13 @@ 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) @@ -763,6 +787,327 @@ 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) { @@ -774,13 +1119,10 @@ 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; @@ -814,53 +1156,42 @@ static void pch_spi_process_messages(struct work_struct *pwork) 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; @@ -881,12 +1212,15 @@ static void pch_spi_process_messages(struct work_struct *pwork) /* 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, @@ -939,6 +1273,35 @@ 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; @@ -946,6 +1309,8 @@ 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) { @@ -959,9 +1324,11 @@ 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; @@ -982,6 +1349,7 @@ 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); @@ -1012,6 +1380,11 @@ 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: @@ -1031,22 +1404,27 @@ 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 */ @@ -1083,8 +1461,8 @@ 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); } @@ -1328,5 +1706,9 @@ 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"); |