/*
* Special handling for DW core on Intel MID platform
*
- * Copyright (c) 2009, Intel Corporation.
+ * Copyright (c) 2009, 2014 Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/dma-mapping.h>
#include "spi-dw.h"
#ifdef CONFIG_SPI_DW_MID_DMA
-#include <linux/intel_mid_dma.h>
#include <linux/pci.h>
+#include <linux/platform_data/dma-dw.h>
-struct mid_dma {
- struct intel_mid_dma_slave dmas_tx;
- struct intel_mid_dma_slave dmas_rx;
-};
+#define RX_BUSY 0
+#define TX_BUSY 1
+
+static struct dw_dma_slave mid_dma_tx = { .dst_id = 1 };
+static struct dw_dma_slave mid_dma_rx = { .src_id = 0 };
static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param)
{
- struct dw_spi *dws = param;
+ struct dw_dma_slave *s = param;
- return dws->dmac && (&dws->dmac->dev == chan->device->dev);
+ if (s->dma_dev != chan->device->dev)
+ return false;
+
+ chan->private = s;
+ return true;
}
static int mid_spi_dma_init(struct dw_spi *dws)
{
- struct mid_dma *dw_dma = dws->dma_priv;
- struct intel_mid_dma_slave *rxs, *txs;
+ struct pci_dev *dma_dev;
+ struct dw_dma_slave *tx = dws->dma_tx;
+ struct dw_dma_slave *rx = dws->dma_rx;
dma_cap_mask_t mask;
/*
* Get pci device for DMA controller, currently it could only
- * be the DMA controller of either Moorestown or Medfield
+ * be the DMA controller of Medfield
*/
- dws->dmac = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0813, NULL);
- if (!dws->dmac)
- dws->dmac = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL);
+ dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL);
+ if (!dma_dev)
+ return -ENODEV;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
/* 1. Init rx channel */
- dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, dws);
+ rx->dma_dev = &dma_dev->dev;
+ dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, rx);
if (!dws->rxchan)
goto err_exit;
- rxs = &dw_dma->dmas_rx;
- rxs->hs_mode = LNW_DMA_HW_HS;
- rxs->cfg_mode = LNW_DMA_PER_TO_MEM;
- dws->rxchan->private = rxs;
+ dws->master->dma_rx = dws->rxchan;
/* 2. Init tx channel */
- dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, dws);
+ tx->dma_dev = &dma_dev->dev;
+ dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, tx);
if (!dws->txchan)
goto free_rxchan;
- txs = &dw_dma->dmas_tx;
- txs->hs_mode = LNW_DMA_HW_HS;
- txs->cfg_mode = LNW_DMA_MEM_TO_PER;
- dws->txchan->private = txs;
+ dws->master->dma_tx = dws->txchan;
dws->dma_inited = 1;
return 0;
free_rxchan:
dma_release_channel(dws->rxchan);
err_exit:
- return -1;
-
+ return -EBUSY;
}
static void mid_spi_dma_exit(struct dw_spi *dws)
dma_release_channel(dws->rxchan);
}
+static irqreturn_t dma_transfer(struct dw_spi *dws)
+{
+ u16 irq_status = dw_readl(dws, DW_SPI_ISR);
+
+ if (!irq_status)
+ return IRQ_NONE;
+
+ dw_readl(dws, DW_SPI_ICR);
+ spi_reset_chip(dws);
+
+ dev_err(&dws->master->dev, "%s: FIFO overrun/underrun\n", __func__);
+ dws->master->cur_msg->status = -EIO;
+ spi_finalize_current_transfer(dws->master);
+ return IRQ_HANDLED;
+}
+
+static bool mid_spi_can_dma(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct dw_spi *dws = spi_master_get_devdata(master);
+
+ if (!dws->dma_inited)
+ return false;
+
+ return xfer->len > dws->fifo_len;
+}
+
+static enum dma_slave_buswidth convert_dma_width(u32 dma_width) {
+ if (dma_width == 1)
+ return DMA_SLAVE_BUSWIDTH_1_BYTE;
+ else if (dma_width == 2)
+ return DMA_SLAVE_BUSWIDTH_2_BYTES;
+
+ return DMA_SLAVE_BUSWIDTH_UNDEFINED;
+}
+
/*
- * dws->dma_chan_done is cleared before the dma transfer starts,
- * callback for rx/tx channel will each increment it by 1.
- * Reaching 2 means the whole spi transaction is done.
+ * dws->dma_chan_busy is set before the dma transfer starts, callback for tx
+ * channel will clear a corresponding bit.
*/
-static void dw_spi_dma_done(void *arg)
+static void dw_spi_dma_tx_done(void *arg)
{
struct dw_spi *dws = arg;
- if (++dws->dma_chan_done != 2)
+ clear_bit(TX_BUSY, &dws->dma_chan_busy);
+ if (test_bit(RX_BUSY, &dws->dma_chan_busy))
return;
- dw_spi_xfer_done(dws);
+ spi_finalize_current_transfer(dws->master);
}
-static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
+static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws,
+ struct spi_transfer *xfer)
{
- struct dma_async_tx_descriptor *txdesc = NULL, *rxdesc = NULL;
- struct dma_chan *txchan, *rxchan;
- struct dma_slave_config txconf, rxconf;
- u16 dma_ctrl = 0;
+ struct dma_slave_config txconf;
+ struct dma_async_tx_descriptor *txdesc;
- /* 1. setup DMA related registers */
- if (cs_change) {
- spi_enable_chip(dws, 0);
- dw_writew(dws, DW_SPI_DMARDLR, 0xf);
- dw_writew(dws, DW_SPI_DMATDLR, 0x10);
- if (dws->tx_dma)
- dma_ctrl |= 0x2;
- if (dws->rx_dma)
- dma_ctrl |= 0x1;
- dw_writew(dws, DW_SPI_DMACR, dma_ctrl);
- spi_enable_chip(dws, 1);
- }
+ if (!xfer->tx_buf)
+ return NULL;
- dws->dma_chan_done = 0;
- txchan = dws->txchan;
- rxchan = dws->rxchan;
-
- /* 2. Prepare the TX dma transfer */
txconf.direction = DMA_MEM_TO_DEV;
txconf.dst_addr = dws->dma_addr;
- txconf.dst_maxburst = LNW_DMA_MSIZE_16;
+ txconf.dst_maxburst = 16;
txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- txconf.dst_addr_width = dws->dma_width;
+ txconf.dst_addr_width = convert_dma_width(dws->dma_width);
txconf.device_fc = false;
- txchan->device->device_control(txchan, DMA_SLAVE_CONFIG,
- (unsigned long) &txconf);
-
- memset(&dws->tx_sgl, 0, sizeof(dws->tx_sgl));
- dws->tx_sgl.dma_address = dws->tx_dma;
- dws->tx_sgl.length = dws->len;
+ dmaengine_slave_config(dws->txchan, &txconf);
- txdesc = dmaengine_prep_slave_sg(txchan,
- &dws->tx_sgl,
- 1,
+ txdesc = dmaengine_prep_slave_sg(dws->txchan,
+ xfer->tx_sg.sgl,
+ xfer->tx_sg.nents,
DMA_MEM_TO_DEV,
- DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_DEST_UNMAP);
- txdesc->callback = dw_spi_dma_done;
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!txdesc)
+ return NULL;
+
+ txdesc->callback = dw_spi_dma_tx_done;
txdesc->callback_param = dws;
- /* 3. Prepare the RX dma transfer */
+ return txdesc;
+}
+
+/*
+ * dws->dma_chan_busy is set before the dma transfer starts, callback for rx
+ * channel will clear a corresponding bit.
+ */
+static void dw_spi_dma_rx_done(void *arg)
+{
+ struct dw_spi *dws = arg;
+
+ clear_bit(RX_BUSY, &dws->dma_chan_busy);
+ if (test_bit(TX_BUSY, &dws->dma_chan_busy))
+ return;
+ spi_finalize_current_transfer(dws->master);
+}
+
+static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws,
+ struct spi_transfer *xfer)
+{
+ struct dma_slave_config rxconf;
+ struct dma_async_tx_descriptor *rxdesc;
+
+ if (!xfer->rx_buf)
+ return NULL;
+
rxconf.direction = DMA_DEV_TO_MEM;
rxconf.src_addr = dws->dma_addr;
- rxconf.src_maxburst = LNW_DMA_MSIZE_16;
+ rxconf.src_maxburst = 16;
rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
- rxconf.src_addr_width = dws->dma_width;
+ rxconf.src_addr_width = convert_dma_width(dws->dma_width);
rxconf.device_fc = false;
- rxchan->device->device_control(rxchan, DMA_SLAVE_CONFIG,
- (unsigned long) &rxconf);
-
- memset(&dws->rx_sgl, 0, sizeof(dws->rx_sgl));
- dws->rx_sgl.dma_address = dws->rx_dma;
- dws->rx_sgl.length = dws->len;
+ dmaengine_slave_config(dws->rxchan, &rxconf);
- rxdesc = dmaengine_prep_slave_sg(rxchan,
- &dws->rx_sgl,
- 1,
+ rxdesc = dmaengine_prep_slave_sg(dws->rxchan,
+ xfer->rx_sg.sgl,
+ xfer->rx_sg.nents,
DMA_DEV_TO_MEM,
- DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_DEST_UNMAP);
- rxdesc->callback = dw_spi_dma_done;
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!rxdesc)
+ return NULL;
+
+ rxdesc->callback = dw_spi_dma_rx_done;
rxdesc->callback_param = dws;
+ return rxdesc;
+}
+
+static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer)
+{
+ u16 dma_ctrl = 0;
+
+ dw_writel(dws, DW_SPI_DMARDLR, 0xf);
+ dw_writel(dws, DW_SPI_DMATDLR, 0x10);
+
+ if (xfer->tx_buf)
+ dma_ctrl |= SPI_DMA_TDMAE;
+ if (xfer->rx_buf)
+ dma_ctrl |= SPI_DMA_RDMAE;
+ dw_writel(dws, DW_SPI_DMACR, dma_ctrl);
+
+ /* Set the interrupt mask */
+ spi_umask_intr(dws, SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI);
+
+ dws->transfer_handler = dma_transfer;
+
+ return 0;
+}
+
+static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer)
+{
+ struct dma_async_tx_descriptor *txdesc, *rxdesc;
+
+ /* Prepare the TX dma transfer */
+ txdesc = dw_spi_dma_prepare_tx(dws, xfer);
+
+ /* Prepare the RX dma transfer */
+ rxdesc = dw_spi_dma_prepare_rx(dws, xfer);
+
/* rx must be started before tx due to spi instinct */
- rxdesc->tx_submit(rxdesc);
- txdesc->tx_submit(txdesc);
+ if (rxdesc) {
+ set_bit(RX_BUSY, &dws->dma_chan_busy);
+ dmaengine_submit(rxdesc);
+ dma_async_issue_pending(dws->rxchan);
+ }
+
+ if (txdesc) {
+ set_bit(TX_BUSY, &dws->dma_chan_busy);
+ dmaengine_submit(txdesc);
+ dma_async_issue_pending(dws->txchan);
+ }
+
return 0;
}
+static void mid_spi_dma_stop(struct dw_spi *dws)
+{
+ if (test_bit(TX_BUSY, &dws->dma_chan_busy)) {
+ dmaengine_terminate_all(dws->txchan);
+ clear_bit(TX_BUSY, &dws->dma_chan_busy);
+ }
+ if (test_bit(RX_BUSY, &dws->dma_chan_busy)) {
+ dmaengine_terminate_all(dws->rxchan);
+ clear_bit(RX_BUSY, &dws->dma_chan_busy);
+ }
+}
+
static struct dw_spi_dma_ops mid_dma_ops = {
.dma_init = mid_spi_dma_init,
.dma_exit = mid_spi_dma_exit,
+ .dma_setup = mid_spi_dma_setup,
+ .can_dma = mid_spi_can_dma,
.dma_transfer = mid_spi_dma_transfer,
+ .dma_stop = mid_spi_dma_stop,
};
#endif
-/* Some specific info for SPI0 controller on Moorestown */
+/* Some specific info for SPI0 controller on Intel MID */
-/* HW info for MRST CLk Control Unit, one 32b reg */
+/* HW info for MRST Clk Control Unit, 32b reg per controller */
#define MRST_SPI_CLK_BASE 100000000 /* 100m */
-#define MRST_CLK_SPI0_REG 0xff11d86c
+#define MRST_CLK_SPI_REG 0xff11d86c
#define CLK_SPI_BDIV_OFFSET 0
#define CLK_SPI_BDIV_MASK 0x00000007
#define CLK_SPI_CDIV_OFFSET 9
void __iomem *clk_reg;
u32 clk_cdiv;
- clk_reg = ioremap_nocache(MRST_CLK_SPI0_REG, 16);
+ clk_reg = ioremap_nocache(MRST_CLK_SPI_REG, 16);
if (!clk_reg)
return -ENOMEM;
- /* get SPI controller operating freq info */
- clk_cdiv = (readl(clk_reg) & CLK_SPI_CDIV_MASK) >> CLK_SPI_CDIV_OFFSET;
+ /* Get SPI controller operating freq info */
+ clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32));
+ clk_cdiv &= CLK_SPI_CDIV_MASK;
+ clk_cdiv >>= CLK_SPI_CDIV_OFFSET;
dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1);
- iounmap(clk_reg);
- dws->num_cs = 16;
+ iounmap(clk_reg);
#ifdef CONFIG_SPI_DW_MID_DMA
- dws->dma_priv = kzalloc(sizeof(struct mid_dma), GFP_KERNEL);
- if (!dws->dma_priv)
- return -ENOMEM;
+ dws->dma_tx = &mid_dma_tx;
+ dws->dma_rx = &mid_dma_rx;
dws->dma_ops = &mid_dma_ops;
#endif
return 0;