pmac.c

linux 内核源代码

/*
 * PMac DBDMA lowlevel functions
 *
 * Copyright (c) by Takashi Iwai <[e-mail]>
 * code based on dmasound.c.
 *
 *   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 program is distributed in the hope that it will be useful,
 *   but WITHOUT 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */


#include <sound/driver.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include "pmac.h"
#include <sound/pcm_params.h>
#include <asm/pmac_feature.h>
#include <asm/pci-bridge.h>


/* fixed frequency table for awacs, screamer, burgundy, DACA (44100 max) */
static int awacs_freqs[8] = {
	44100, 29400, 22050, 17640, 14700, 11025, 8820, 7350
};
/* fixed frequency table for tumbler */
static int tumbler_freqs[1] = {
	44100
};

/*
 * allocate DBDMA command arrays
 */
static int snd_pmac_dbdma_alloc(struct snd_pmac *chip, struct pmac_dbdma *rec, int size)
{
	unsigned int rsize = sizeof(struct dbdma_cmd) * (size + 1);

	rec->space = dma_alloc_coherent(&chip->pdev->dev, rsize,
					&rec->dma_base, GFP_KERNEL);
	if (rec->space == NULL)
		return -ENOMEM;
	rec->size = size;
	memset(rec->space, 0, rsize);
	rec->cmds = (void __iomem *)DBDMA_ALIGN(rec->space);
	rec->addr = rec->dma_base + (unsigned long)((char *)rec->cmds - (char *)rec->space);

	return 0;
}

static void snd_pmac_dbdma_free(struct snd_pmac *chip, struct pmac_dbdma *rec)
{
	if (rec->space) {
		unsigned int rsize = sizeof(struct dbdma_cmd) * (rec->size + 1);

		dma_free_coherent(&chip->pdev->dev, rsize, rec->space, rec->dma_base);
	}
}


/*
 * pcm stuff
 */

/*
 * look up frequency table
 */

unsigned int snd_pmac_rate_index(struct snd_pmac *chip, struct pmac_stream *rec, unsigned int rate)
{
	int i, ok, found;

	ok = rec->cur_freqs;
	if (rate > chip->freq_table[0])
		return 0;
	found = 0;
	for (i = 0; i < chip->num_freqs; i++, ok >>= 1) {
		if (! (ok & 1)) continue;
		found = i;
		if (rate >= chip->freq_table[i])
			break;
	}
	return found;
}

/*
 * check whether another stream is active
 */
static inline int another_stream(int stream)
{
	return (stream == SNDRV_PCM_STREAM_PLAYBACK) ?
		SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
}

/*
 * allocate buffers
 */
static int snd_pmac_pcm_hw_params(struct snd_pcm_substream *subs,
				  struct snd_pcm_hw_params *hw_params)
{
	return snd_pcm_lib_malloc_pages(subs, params_buffer_bytes(hw_params));
}

/*
 * release buffers
 */
static int snd_pmac_pcm_hw_free(struct snd_pcm_substream *subs)
{
	snd_pcm_lib_free_pages(subs);
	return 0;
}

/*
 * get a stream of the opposite direction
 */
static struct pmac_stream *snd_pmac_get_stream(struct snd_pmac *chip, int stream)
{
	switch (stream) {
	case SNDRV_PCM_STREAM_PLAYBACK:
		return &chip->playback;
	case SNDRV_PCM_STREAM_CAPTURE:
		return &chip->capture;
	default:
		snd_BUG();
		return NULL;
	}
}

/*
 * wait while run status is on
 */
static inline void
snd_pmac_wait_ack(struct pmac_stream *rec)
{
	int timeout = 50000;
	while ((in_le32(&rec->dma->status) & RUN) && timeout-- > 0)
		udelay(1);
}

/*
 * set the format and rate to the chip.
 * call the lowlevel function if defined (e.g. for AWACS).
 */
static void snd_pmac_pcm_set_format(struct snd_pmac *chip)
{
	/* set up frequency and format */
	out_le32(&chip->awacs->control, chip->control_mask | (chip->rate_index << 8));
	out_le32(&chip->awacs->byteswap, chip->format == SNDRV_PCM_FORMAT_S16_LE ? 1 : 0);
	if (chip->set_format)
		chip->set_format(chip);
}

/*
 * stop the DMA transfer
 */
static inline void snd_pmac_dma_stop(struct pmac_stream *rec)
{
	out_le32(&rec->dma->control, (RUN|WAKE|FLUSH|PAUSE) << 16);
	snd_pmac_wait_ack(rec);
}

/*
 * set the command pointer address
 */
static inline void snd_pmac_dma_set_command(struct pmac_stream *rec, struct pmac_dbdma *cmd)
{
	out_le32(&rec->dma->cmdptr, cmd->addr);
}

/*
 * start the DMA
 */
static inline void snd_pmac_dma_run(struct pmac_stream *rec, int status)
{
	out_le32(&rec->dma->control, status | (status << 16));
}


/*
 * prepare playback/capture stream
 */
static int snd_pmac_pcm_prepare(struct snd_pmac *chip, struct pmac_stream *rec, struct snd_pcm_substream *subs)
{
	int i;
	volatile struct dbdma_cmd __iomem *cp;
	struct snd_pcm_runtime *runtime = subs->runtime;
	int rate_index;
	long offset;
	struct pmac_stream *astr;
	
	rec->dma_size = snd_pcm_lib_buffer_bytes(subs);
	rec->period_size = snd_pcm_lib_period_bytes(subs);
	rec->nperiods = rec->dma_size / rec->period_size;
	rec->cur_period = 0;
	rate_index = snd_pmac_rate_index(chip, rec, runtime->rate);

	/* set up constraints */
	astr = snd_pmac_get_stream(chip, another_stream(rec->stream));
	if (! astr)
		return -EINVAL;
	astr->cur_freqs = 1 << rate_index;
	astr->cur_formats = 1 << runtime->format;
	chip->rate_index = rate_index;
	chip->format = runtime->format;

	/* We really want to execute a DMA stop command, after the AWACS
	 * is initialized.
	 * For reasons I don't understand, it stops the hissing noise
	 * common to many PowerBook G3 systems and random noise otherwise
	 * captured on iBook2's about every third time. -ReneR
	 */
	spin_lock_irq(&chip->reg_lock);
	snd_pmac_dma_stop(rec);
	st_le16(&chip->extra_dma.cmds->command, DBDMA_STOP);
	snd_pmac_dma_set_command(rec, &chip->extra_dma);
	snd_pmac_dma_run(rec, RUN);
	spin_unlock_irq(&chip->reg_lock);
	mdelay(5);
	spin_lock_irq(&chip->reg_lock);
	/* continuous DMA memory type doesn't provide the physical address,
	 * so we need to resolve the address here...
	 */
	offset = runtime->dma_addr;
	for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++) {
		st_le32(&cp->phy_addr, offset);
		st_le16(&cp->req_count, rec->period_size);
		/*st_le16(&cp->res_count, 0);*/
		st_le16(&cp->xfer_status, 0);
		offset += rec->period_size;
	}
	/* make loop */
	st_le16(&cp->command, DBDMA_NOP + BR_ALWAYS);
	st_le32(&cp->cmd_dep, rec->cmd.addr);

	snd_pmac_dma_stop(rec);
	snd_pmac_dma_set_command(rec, &rec->cmd);
	spin_unlock_irq(&chip->reg_lock);

	return 0;
}


/*
 * PCM trigger/stop
 */
static int snd_pmac_pcm_trigger(struct snd_pmac *chip, struct pmac_stream *rec,
				struct snd_pcm_substream *subs, int cmd)
{
	volatile struct dbdma_cmd __iomem *cp;
	int i, command;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		if (rec->running)
			return -EBUSY;
		command = (subs->stream == SNDRV_PCM_STREAM_PLAYBACK ?
			   OUTPUT_MORE : INPUT_MORE) + INTR_ALWAYS;
		spin_lock(&chip->reg_lock);
		snd_pmac_beep_stop(chip);
		snd_pmac_pcm_set_format(chip);
		for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++)
			out_le16(&cp->command, command);
		snd_pmac_dma_set_command(rec, &rec->cmd);
		(void)in_le32(&rec->dma->status);
		snd_pmac_dma_run(rec, RUN|WAKE);
		rec->running = 1;
		spin_unlock(&chip->reg_lock);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		spin_lock(&chip->reg_lock);
		rec->running = 0;
		/*printk("stopped!!\n");*/
		snd_pmac_dma_stop(rec);
		for (i = 0, cp = rec->cmd.cmds; i < rec->nperiods; i++, cp++)
			out_le16(&cp->command, DBDMA_STOP);
		spin_unlock(&chip->reg_lock);
		break;

	default:
		return -EINVAL;
	}

	return 0;
}

/*
 * return the current pointer
 */
inline
static snd_pcm_uframes_t snd_pmac_pcm_pointer(struct snd_pmac *chip,
					      struct pmac_stream *rec,
					      struct snd_pcm_substream *subs)
{
	int count = 0;

#if 1 /* hmm.. how can we get the current dma pointer?? */
	int stat;
	volatile struct dbdma_cmd __iomem *cp = &rec->cmd.cmds[rec->cur_period];
	stat = ld_le16(&cp->xfer_status);
	if (stat & (ACTIVE|DEAD)) {
		count = in_le16(&cp->res_count);
		if (count)
			count = rec->period_size - count;
	}
#endif
	count += rec->cur_period * rec->period_size;
	/*printk("pointer=%d\n", count);*/
	return bytes_to_frames(subs->runtime, count);
}

/*
 * playback
 */

static int snd_pmac_playback_prepare(struct snd_pcm_substream *subs)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_prepare(chip, &chip->playback, subs);
}

static int snd_pmac_playback_trigger(struct snd_pcm_substream *subs,
				     int cmd)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_trigger(chip, &chip->playback, subs, cmd);
}

static snd_pcm_uframes_t snd_pmac_playback_pointer(struct snd_pcm_substream *subs)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_pointer(chip, &chip->playback, subs);
}


/*
 * capture
 */

static int snd_pmac_capture_prepare(struct snd_pcm_substream *subs)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_prepare(chip, &chip->capture, subs);
}

static int snd_pmac_capture_trigger(struct snd_pcm_substream *subs,
				    int cmd)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_trigger(chip, &chip->capture, subs, cmd);
}

static snd_pcm_uframes_t snd_pmac_capture_pointer(struct snd_pcm_substream *subs)
{
	struct snd_pmac *chip = snd_pcm_substream_chip(subs);
	return snd_pmac_pcm_pointer(chip, &chip->capture, subs);
}


/*
 * update playback/capture pointer from interrupts
 */
static void snd_pmac_pcm_update(struct snd_pmac *chip, struct pmac_stream *rec)
{
	volatile struct dbdma_cmd __iomem *cp;
	int c;
	int stat;

	spin_lock(&chip->reg_lock);
	if (rec->running) {
		cp = &rec->cmd.cmds[rec->cur_period];
		for (c = 0; c < rec->nperiods; c++) { /* at most all fragments */
			stat = ld_le16(&cp->xfer_status);
			if (! (stat & ACTIVE))
				break;
			/*printk("update frag %d\n", rec->cur_period);*/
			st_le16(&cp->xfer_status, 0);
			st_le16(&cp->req_count, rec->period_size);
			/*st_le16(&cp->res_count, 0);*/
			rec->cur_period++;
			if (rec->cur_period >= rec->nperiods) {
				rec->cur_period = 0;
				cp = rec->cmd.cmds;
			} else
				cp++;
			spin_unlock(&chip->reg_lock);
			snd_pcm_period_elapsed(rec->substream);
			spin_lock(&chip->reg_lock);
		}
	}
	spin_unlock(&chip->reg_lock);
}


/*
 * hw info
 */

static struct snd_pcm_hardware snd_pmac_playback =
{
	.info =			(SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_MMAP |
				 SNDRV_PCM_INFO_MMAP_VALID |
				 SNDRV_PCM_INFO_RESUME),
	.formats =		SNDRV_PCM_FMTBIT_S16_BE | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_8000_44100,
	.rate_min =		7350,
	.rate_max =		44100,
	.channels_min =		2,
	.channels_max =		2,
	.buffer_bytes_max =	131072,
	.period_bytes_min =	256,
	.period_bytes_max =	16384,
	.periods_min =		3,
	.periods_max =		PMAC_MAX_FRAGS,
};

static struct snd_pcm_hardware snd_pmac_capture =
{
	.info =			(SNDRV_PCM_INFO_INTERLEAVED |
				 SNDRV_PCM_INFO_MMAP |