arch/mips/au1000/common/dma.c - maze/linux - Git at Google

 /*
  *
  * BRIEF MODULE DESCRIPTION
  *      A DMA channel allocator for Au1000. API is modeled loosely off of
  *      linux/kernel/dma.c.
  *
  * Copyright 2000 MontaVista Software Inc.
  * Author: MontaVista Software, Inc.
  *         	stevel@mvista.com or source@mvista.com
  * Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
  *
  *  This program is free software; you can redistribute  it and/or modify it
  *  under  the terms of  the GNU General  Public License as published by the
  *  Free Software Foundation;  either version 2 of the  License, or (at your
  *  option) any later version.
  *
  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  *  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.,
  *  675 Mass Ave, Cambridge, MA 02139, USA.
  *
  */
 #include <linux/config.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <asm/system.h>
 #include <asm/mach-au1x00/au1000.h>
 #include <asm/mach-au1x00/au1000_dma.h>

 #if defined(CONFIG_SOC_AU1000) || defined(CONFIG_SOC_AU1500) || defined(CONFIG_SOC_AU1100)
 /*
  * A note on resource allocation:
  *
  * All drivers needing DMA channels, should allocate and release them
  * through the public routines `request_dma()' and `free_dma()'.
  *
  * In order to avoid problems, all processes should allocate resources in
  * the same sequence and release them in the reverse order.
  *
  * So, when allocating DMAs and IRQs, first allocate the DMA, then the IRQ.
  * When releasing them, first release the IRQ, then release the DMA. The
  * main reason for this order is that, if you are requesting the DMA buffer
  * done interrupt, you won't know the irq number until the DMA channel is
  * returned from request_dma.
  */


 DEFINE_SPINLOCK(au1000_dma_spin_lock);

 struct dma_chan au1000_dma_table[NUM_AU1000_DMA_CHANNELS] = {
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,},
       {.dev_id = -1,}
 };
 EXPORT_SYMBOL(au1000_dma_table);

 // Device FIFO addresses and default DMA modes
 static const struct dma_dev {
 	unsigned int fifo_addr;
 	unsigned int dma_mode;
 } dma_dev_table[DMA_NUM_DEV] = {
 	{UART0_ADDR + UART_TX, 0},
 	{UART0_ADDR + UART_RX, 0},
 	{0, 0},
 	{0, 0},
 	{AC97C_DATA, DMA_DW16 },          // coherent
 	{AC97C_DATA, DMA_DR | DMA_DW16 }, // coherent
 	{UART3_ADDR + UART_TX, DMA_DW8 | DMA_NC},
 	{UART3_ADDR + UART_RX, DMA_DR | DMA_DW8 | DMA_NC},
 	{USBD_EP0RD, DMA_DR | DMA_DW8 | DMA_NC},
 	{USBD_EP0WR, DMA_DW8 | DMA_NC},
 	{USBD_EP2WR, DMA_DW8 | DMA_NC},
 	{USBD_EP3WR, DMA_DW8 | DMA_NC},
 	{USBD_EP4RD, DMA_DR | DMA_DW8 | DMA_NC},
 	{USBD_EP5RD, DMA_DR | DMA_DW8 | DMA_NC},
 	{I2S_DATA, DMA_DW32 | DMA_NC},
 	{I2S_DATA, DMA_DR | DMA_DW32 | DMA_NC}
 };

 int au1000_dma_read_proc(char *buf, char **start, off_t fpos,
 			 int length, int *eof, void *data)
 {
 	int i, len = 0;
 	struct dma_chan *chan;

 	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
 		if ((chan = get_dma_chan(i)) != NULL) {
 			len += sprintf(buf + len, "%2d: %s\n",
 				       i, chan->dev_str);
 		}
 	}

 	if (fpos >= len) {
 		*start = buf;
 		*eof = 1;
 		return 0;
 	}
 	*start = buf + fpos;
 	if ((len -= fpos) > length)
 		return length;
 	*eof = 1;
 	return len;
 }

 // Device FIFO addresses and default DMA modes - 2nd bank
 static const struct dma_dev dma_dev_table_bank2[DMA_NUM_DEV_BANK2] = {
 	{SD0_XMIT_FIFO, DMA_DS | DMA_DW8},		// coherent
 	{SD0_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8},	// coherent
 	{SD1_XMIT_FIFO, DMA_DS | DMA_DW8},		// coherent
 	{SD1_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8}	// coherent
 };

 void dump_au1000_dma_channel(unsigned int dmanr)
 {
 	struct dma_chan *chan;

 	if (dmanr >= NUM_AU1000_DMA_CHANNELS)
 		return;
 	chan = &au1000_dma_table[dmanr];

 	printk(KERN_INFO "Au1000 DMA%d Register Dump:\n", dmanr);
 	printk(KERN_INFO "  mode = 0x%08x\n",
 	       au_readl(chan->io + DMA_MODE_SET));
 	printk(KERN_INFO "  addr = 0x%08x\n",
 	       au_readl(chan->io + DMA_PERIPHERAL_ADDR));
 	printk(KERN_INFO "  start0 = 0x%08x\n",
 	       au_readl(chan->io + DMA_BUFFER0_START));
 	printk(KERN_INFO "  start1 = 0x%08x\n",
 	       au_readl(chan->io + DMA_BUFFER1_START));
 	printk(KERN_INFO "  count0 = 0x%08x\n",
 	       au_readl(chan->io + DMA_BUFFER0_COUNT));
 	printk(KERN_INFO "  count1 = 0x%08x\n",
 	       au_readl(chan->io + DMA_BUFFER1_COUNT));
 }


 /*
  * Finds a free channel, and binds the requested device to it.
  * Returns the allocated channel number, or negative on error.
  * Requests the DMA done IRQ if irqhandler != NULL.
  */
 int request_au1000_dma(int dev_id, const char *dev_str,
 		       irqreturn_t (*irqhandler)(int, void *, struct pt_regs *),
 		       unsigned long irqflags,
 		       void *irq_dev_id)
 {
 	struct dma_chan *chan;
 	const struct dma_dev *dev;
 	int i, ret;

 #if defined(CONFIG_SOC_AU1100)
 	if (dev_id < 0 || dev_id >= (DMA_NUM_DEV + DMA_NUM_DEV_BANK2))
 		return -EINVAL;
 #else
  	if (dev_id < 0 || dev_id >= DMA_NUM_DEV)
  		return -EINVAL;
 #endif

 	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
 		if (au1000_dma_table[i].dev_id < 0)
 			break;
 	}
 	if (i == NUM_AU1000_DMA_CHANNELS)
 		return -ENODEV;

 	chan = &au1000_dma_table[i];

 	if (dev_id >= DMA_NUM_DEV) {
 		dev_id -= DMA_NUM_DEV;
 		dev = &dma_dev_table_bank2[dev_id];
 	} else {
 		dev = &dma_dev_table[dev_id];
 	}

 	if (irqhandler) {
 		chan->irq = AU1000_DMA_INT_BASE + i;
 		chan->irq_dev = irq_dev_id;
 		if ((ret = request_irq(chan->irq, irqhandler, irqflags,
 				       dev_str, chan->irq_dev))) {
 			chan->irq = 0;
 			chan->irq_dev = NULL;
 			return ret;
 		}
 	} else {
 		chan->irq = 0;
 		chan->irq_dev = NULL;
 	}

 	// fill it in
 	chan->io = DMA_CHANNEL_BASE + i * DMA_CHANNEL_LEN;
 	chan->dev_id = dev_id;
 	chan->dev_str = dev_str;
 	chan->fifo_addr = dev->fifo_addr;
 	chan->mode = dev->dma_mode;

 	/* initialize the channel before returning */
 	init_dma(i);

 	return i;
 }
 EXPORT_SYMBOL(request_au1000_dma);

 void free_au1000_dma(unsigned int dmanr)
 {
 	struct dma_chan *chan = get_dma_chan(dmanr);
 	if (!chan) {
 		printk("Trying to free DMA%d\n", dmanr);
 		return;
 	}

 	disable_dma(dmanr);
 	if (chan->irq)
 		free_irq(chan->irq, chan->irq_dev);

 	chan->irq = 0;
 	chan->irq_dev = NULL;
 	chan->dev_id = -1;
 }
 EXPORT_SYMBOL(free_au1000_dma);

 #endif // AU1000 AU1500 AU1100
	/*
	*
	* BRIEF MODULE DESCRIPTION
	* A DMA channel allocator for Au1000. API is modeled loosely off of
	* linux/kernel/dma.c.
	*
	* Copyright 2000 MontaVista Software Inc.
	* Author: MontaVista Software, Inc.
	* stevel@mvista.com or source@mvista.com
	* Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License as published by the
	* Free Software Foundation; either version 2 of the License, or (at your
	* option) any later version.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
	* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
	* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	* 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.,
	* 675 Mass Ave, Cambridge, MA 02139, USA.
	*
	*/
	#include <linux/config.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/sched.h>
	#include <linux/spinlock.h>
	#include <linux/string.h>
	#include <linux/delay.h>
	#include <linux/interrupt.h>
	#include <asm/system.h>
	#include <asm/mach-au1x00/au1000.h>
	#include <asm/mach-au1x00/au1000_dma.h>

	#if defined(CONFIG_SOC_AU1000) \|\| defined(CONFIG_SOC_AU1500) \|\| defined(CONFIG_SOC_AU1100)
	/*
	* A note on resource allocation:
	*
	* All drivers needing DMA channels, should allocate and release them
	* through the public routines `request_dma()' and `free_dma()'.
	*
	* In order to avoid problems, all processes should allocate resources in
	* the same sequence and release them in the reverse order.
	*
	* So, when allocating DMAs and IRQs, first allocate the DMA, then the IRQ.
	* When releasing them, first release the IRQ, then release the DMA. The
	* main reason for this order is that, if you are requesting the DMA buffer
	* done interrupt, you won't know the irq number until the DMA channel is
	* returned from request_dma.
	*/


	DEFINE_SPINLOCK(au1000_dma_spin_lock);

	struct dma_chan au1000_dma_table[NUM_AU1000_DMA_CHANNELS] = {
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,},
	{.dev_id = -1,}
	};
	EXPORT_SYMBOL(au1000_dma_table);

	// Device FIFO addresses and default DMA modes
	static const struct dma_dev {
	unsigned int fifo_addr;
	unsigned int dma_mode;
	} dma_dev_table[DMA_NUM_DEV] = {
	{UART0_ADDR + UART_TX, 0},
	{UART0_ADDR + UART_RX, 0},
	{0, 0},
	{0, 0},
	{AC97C_DATA, DMA_DW16 }, // coherent
	{AC97C_DATA, DMA_DR \| DMA_DW16 }, // coherent
	{UART3_ADDR + UART_TX, DMA_DW8 \| DMA_NC},
	{UART3_ADDR + UART_RX, DMA_DR \| DMA_DW8 \| DMA_NC},
	{USBD_EP0RD, DMA_DR \| DMA_DW8 \| DMA_NC},
	{USBD_EP0WR, DMA_DW8 \| DMA_NC},
	{USBD_EP2WR, DMA_DW8 \| DMA_NC},
	{USBD_EP3WR, DMA_DW8 \| DMA_NC},
	{USBD_EP4RD, DMA_DR \| DMA_DW8 \| DMA_NC},
	{USBD_EP5RD, DMA_DR \| DMA_DW8 \| DMA_NC},
	{I2S_DATA, DMA_DW32 \| DMA_NC},
	{I2S_DATA, DMA_DR \| DMA_DW32 \| DMA_NC}
	};

	int au1000_dma_read_proc(char buf, char *start, off_t fpos,
	int length, int eof, void data)
	{
	int i, len = 0;
	struct dma_chan *chan;

	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
	if ((chan = get_dma_chan(i)) != NULL) {
	len += sprintf(buf + len, "%2d: %s\n",
	i, chan->dev_str);
	}
	}

	if (fpos >= len) {
	*start = buf;
	*eof = 1;
	return 0;
	}
	*start = buf + fpos;
	if ((len -= fpos) > length)
	return length;
	*eof = 1;
	return len;
	}

	// Device FIFO addresses and default DMA modes - 2nd bank
	static const struct dma_dev dma_dev_table_bank2[DMA_NUM_DEV_BANK2] = {
	{SD0_XMIT_FIFO, DMA_DS \| DMA_DW8}, // coherent
	{SD0_RECV_FIFO, DMA_DS \| DMA_DR \| DMA_DW8}, // coherent
	{SD1_XMIT_FIFO, DMA_DS \| DMA_DW8}, // coherent
	{SD1_RECV_FIFO, DMA_DS \| DMA_DR \| DMA_DW8} // coherent
	};

	void dump_au1000_dma_channel(unsigned int dmanr)
	{
	struct dma_chan *chan;

	if (dmanr >= NUM_AU1000_DMA_CHANNELS)
	return;
	chan = &au1000_dma_table[dmanr];

	printk(KERN_INFO "Au1000 DMA%d Register Dump:\n", dmanr);
	printk(KERN_INFO " mode = 0x%08x\n",
	au_readl(chan->io + DMA_MODE_SET));
	printk(KERN_INFO " addr = 0x%08x\n",
	au_readl(chan->io + DMA_PERIPHERAL_ADDR));
	printk(KERN_INFO " start0 = 0x%08x\n",
	au_readl(chan->io + DMA_BUFFER0_START));
	printk(KERN_INFO " start1 = 0x%08x\n",
	au_readl(chan->io + DMA_BUFFER1_START));
	printk(KERN_INFO " count0 = 0x%08x\n",
	au_readl(chan->io + DMA_BUFFER0_COUNT));
	printk(KERN_INFO " count1 = 0x%08x\n",
	au_readl(chan->io + DMA_BUFFER1_COUNT));
	}


	/*
	* Finds a free channel, and binds the requested device to it.
	* Returns the allocated channel number, or negative on error.
	* Requests the DMA done IRQ if irqhandler != NULL.
	*/
	int request_au1000_dma(int dev_id, const char *dev_str,
	irqreturn_t (irqhandler)(int, void , struct pt_regs *),
	unsigned long irqflags,
	void *irq_dev_id)
	{
	struct dma_chan *chan;
	const struct dma_dev *dev;
	int i, ret;

	#if defined(CONFIG_SOC_AU1100)
	if (dev_id < 0 \|\| dev_id >= (DMA_NUM_DEV + DMA_NUM_DEV_BANK2))
	return -EINVAL;
	#else
	if (dev_id < 0 \|\| dev_id >= DMA_NUM_DEV)
	return -EINVAL;
	#endif

	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
	if (au1000_dma_table[i].dev_id < 0)
	break;
	}
	if (i == NUM_AU1000_DMA_CHANNELS)
	return -ENODEV;

	chan = &au1000_dma_table[i];

	if (dev_id >= DMA_NUM_DEV) {
	dev_id -= DMA_NUM_DEV;
	dev = &dma_dev_table_bank2[dev_id];
	} else {
	dev = &dma_dev_table[dev_id];
	}

	if (irqhandler) {
	chan->irq = AU1000_DMA_INT_BASE + i;
	chan->irq_dev = irq_dev_id;
	if ((ret = request_irq(chan->irq, irqhandler, irqflags,
	dev_str, chan->irq_dev))) {
	chan->irq = 0;
	chan->irq_dev = NULL;
	return ret;
	}
	} else {
	chan->irq = 0;
	chan->irq_dev = NULL;
	}

	// fill it in
	chan->io = DMA_CHANNEL_BASE + i * DMA_CHANNEL_LEN;
	chan->dev_id = dev_id;
	chan->dev_str = dev_str;
	chan->fifo_addr = dev->fifo_addr;
	chan->mode = dev->dma_mode;

	/* initialize the channel before returning */
	init_dma(i);

	return i;
	}
	EXPORT_SYMBOL(request_au1000_dma);

	void free_au1000_dma(unsigned int dmanr)
	{
	struct dma_chan *chan = get_dma_chan(dmanr);
	if (!chan) {
	printk("Trying to free DMA%d\n", dmanr);
	return;
	}

	disable_dma(dmanr);
	if (chan->irq)
	free_irq(chan->irq, chan->irq_dev);

	chan->irq = 0;
	chan->irq_dev = NULL;
	chan->dev_id = -1;
	}
	EXPORT_SYMBOL(free_au1000_dma);

	#endif // AU1000 AU1500 AU1100