[ALSA] hda-intel - Use SG buffer

Use SG buffers for the HD-audio instead of linear buffers.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 18475de..b38a5a7 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -206,8 +206,9 @@
 #define MAX_AZX_DEV		16
 
 /* max number of fragments - we may use more if allocating more pages for BDL */
-#define BDL_SIZE		PAGE_ALIGN(8192)
-#define AZX_MAX_FRAG		(BDL_SIZE / (MAX_AZX_DEV * 16))
+#define BDL_SIZE		4096
+#define AZX_MAX_BDL_ENTRIES	(BDL_SIZE / 16)
+#define AZX_MAX_FRAG		32
 /* max buffer size - no h/w limit, you can increase as you like */
 #define AZX_MAX_BUF_SIZE	(1024*1024*1024)
 /* max number of PCM devics per card */
@@ -282,12 +283,10 @@
  */
 
 struct azx_dev {
-	u32 *bdl;		/* virtual address of the BDL */
-	dma_addr_t bdl_addr;	/* physical address of the BDL */
+	struct snd_dma_buffer bdl; /* BDL buffer */
 	u32 *posbuf;		/* position buffer pointer */
 
 	unsigned int bufsize;	/* size of the play buffer in bytes */
-	unsigned int fragsize;	/* size of each period in bytes */
 	unsigned int frags;	/* number for period in the play buffer */
 	unsigned int fifo_size;	/* FIFO size */
 
@@ -358,8 +357,7 @@
 	struct azx_rb corb;
 	struct azx_rb rirb;
 
-	/* BDL, CORB/RIRB and position buffers */
-	struct snd_dma_buffer bdl;
+	/* CORB/RIRB and position buffers */
 	struct snd_dma_buffer rb;
 	struct snd_dma_buffer posbuf;
 
@@ -962,30 +960,57 @@
 /*
  * set up BDL entries
  */
-static void azx_setup_periods(struct azx_dev *azx_dev)
+static int azx_setup_periods(struct snd_pcm_substream *substream,
+			     struct azx_dev *azx_dev)
 {
-	u32 *bdl = azx_dev->bdl;
-	dma_addr_t dma_addr = azx_dev->substream->runtime->dma_addr;
-	int idx;
+	struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
+	u32 *bdl;
+	int i, ofs, periods, period_bytes;
 
 	/* reset BDL address */
 	azx_sd_writel(azx_dev, SD_BDLPL, 0);
 	azx_sd_writel(azx_dev, SD_BDLPU, 0);
 
+	period_bytes = snd_pcm_lib_period_bytes(substream);
+	periods = azx_dev->bufsize / period_bytes;
+
 	/* program the initial BDL entries */
-	for (idx = 0; idx < azx_dev->frags; idx++) {
-		unsigned int off = idx << 2; /* 4 dword step */
-		dma_addr_t addr = dma_addr + idx * azx_dev->fragsize;
-		/* program the address field of the BDL entry */
-		bdl[off] = cpu_to_le32((u32)addr);
-		bdl[off+1] = cpu_to_le32(upper_32bit(addr));
-
-		/* program the size field of the BDL entry */
-		bdl[off+2] = cpu_to_le32(azx_dev->fragsize);
-
-		/* program the IOC to enable interrupt when buffer completes */
-		bdl[off+3] = cpu_to_le32(0x01);
+	bdl = (u32 *)azx_dev->bdl.area;
+	ofs = 0;
+	azx_dev->frags = 0;
+	for (i = 0; i < periods; i++) {
+		int size, rest;
+		if (i >= AZX_MAX_BDL_ENTRIES) {
+			snd_printk(KERN_ERR "Too many BDL entries: "
+				   "buffer=%d, period=%d\n",
+				   azx_dev->bufsize, period_bytes);
+			/* reset */
+			azx_sd_writel(azx_dev, SD_BDLPL, 0);
+			azx_sd_writel(azx_dev, SD_BDLPU, 0);
+			return -EINVAL;
+		}
+		rest = period_bytes;
+		do {
+			dma_addr_t addr = snd_pcm_sgbuf_get_addr(sgbuf, ofs);
+			/* program the address field of the BDL entry */
+			bdl[0] = cpu_to_le32((u32)addr);
+			bdl[1] = cpu_to_le32(upper_32bit(addr));
+			/* program the size field of the BDL entry */
+			size = PAGE_SIZE - (ofs % PAGE_SIZE);
+			if (rest < size)
+				size = rest;
+			bdl[2] = cpu_to_le32(size);
+			/* program the IOC to enable interrupt
+			 * only when the whole fragment is processed
+			 */
+			rest -= size;
+			bdl[3] = rest ? 0 : cpu_to_le32(0x01);
+			bdl += 4;
+			azx_dev->frags++;
+			ofs += size;
+		} while (rest > 0);
 	}
+	return 0;
 }
 
 /*
@@ -1034,9 +1059,9 @@
 
 	/* program the BDL address */
 	/* lower BDL address */
-	azx_sd_writel(azx_dev, SD_BDLPL, (u32)azx_dev->bdl_addr);
+	azx_sd_writel(azx_dev, SD_BDLPL, (u32)azx_dev->bdl.addr);
 	/* upper BDL address */
-	azx_sd_writel(azx_dev, SD_BDLPU, upper_32bit(azx_dev->bdl_addr));
+	azx_sd_writel(azx_dev, SD_BDLPU, upper_32bit(azx_dev->bdl.addr));
 
 	/* enable the position buffer */
 	if (!(azx_readl(chip, DPLBASE) & ICH6_DPLBASE_ENABLE))
@@ -1272,8 +1297,6 @@
 	struct snd_pcm_runtime *runtime = substream->runtime;
 
 	azx_dev->bufsize = snd_pcm_lib_buffer_bytes(substream);
-	azx_dev->fragsize = snd_pcm_lib_period_bytes(substream);
-	azx_dev->frags = azx_dev->bufsize / azx_dev->fragsize;
 	azx_dev->format_val = snd_hda_calc_stream_format(runtime->rate,
 							 runtime->channels,
 							 runtime->format,
@@ -1288,7 +1311,8 @@
 	snd_printdd("azx_pcm_prepare: bufsize=0x%x, fragsize=0x%x, "
 		    "format=0x%x\n",
 		    azx_dev->bufsize, azx_dev->fragsize, azx_dev->format_val);
-	azx_setup_periods(azx_dev);
+	if (azx_setup_periods(substream, azx_dev) < 0)
+		return -EINVAL;
 	azx_setup_controller(chip, azx_dev);
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		azx_dev->fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE) + 1;
@@ -1375,6 +1399,7 @@
 	.prepare = azx_pcm_prepare,
 	.trigger = azx_pcm_trigger,
 	.pointer = azx_pcm_pointer,
+	.page = snd_pcm_sgbuf_ops_page,
 };
 
 static void azx_pcm_free(struct snd_pcm *pcm)
@@ -1417,7 +1442,7 @@
 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &azx_pcm_ops);
 	if (cpcm->stream[1].substreams)
 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &azx_pcm_ops);
-	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV_SG,
 					      snd_dma_pci_data(chip->pci),
 					      1024 * 64, 1024 * 1024);
 	chip->pcm[cpcm->device] = pcm;
@@ -1507,10 +1532,7 @@
 	 * and initialize
 	 */
 	for (i = 0; i < chip->num_streams; i++) {
-		unsigned int off = sizeof(u32) * (i * AZX_MAX_FRAG * 4);
 		struct azx_dev *azx_dev = &chip->azx_dev[i];
-		azx_dev->bdl = (u32 *)(chip->bdl.area + off);
-		azx_dev->bdl_addr = chip->bdl.addr + off;
 		azx_dev->posbuf = (u32 __iomem *)(chip->posbuf.area + i * 8);
 		/* offset: SDI0=0x80, SDI1=0xa0, ... SDO3=0x160 */
 		azx_dev->sd_addr = chip->remap_addr + (0x20 * i + 0x80);
@@ -1646,8 +1668,9 @@
  */
 static int azx_free(struct azx *chip)
 {
+	int i;
+
 	if (chip->initialized) {
-		int i;
 		for (i = 0; i < chip->num_streams; i++)
 			azx_stream_stop(chip, &chip->azx_dev[i]);
 		azx_stop_chip(chip);
@@ -1662,8 +1685,11 @@
 	if (chip->remap_addr)
 		iounmap(chip->remap_addr);
 
-	if (chip->bdl.area)
-		snd_dma_free_pages(&chip->bdl);
+	if (chip->azx_dev) {
+		for (i = 0; i < chip->num_streams; i++)
+			if (chip->azx_dev[i].bdl.area)
+				snd_dma_free_pages(&chip->azx_dev[i].bdl);
+	}
 	if (chip->rb.area)
 		snd_dma_free_pages(&chip->rb);
 	if (chip->posbuf.area)
@@ -1745,7 +1771,7 @@
 				struct azx **rchip)
 {
 	struct azx *chip;
-	int err;
+	int i, err;
 	unsigned short gcap;
 	static struct snd_device_ops ops = {
 		.dev_free = azx_dev_free,
@@ -1857,13 +1883,15 @@
 		goto errout;
 	}
 
-	/* allocate memory for the BDL for each stream */
-	err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
-				  snd_dma_pci_data(chip->pci),
-				  BDL_SIZE, &chip->bdl);
-	if (err < 0) {
-		snd_printk(KERN_ERR SFX "cannot allocate BDL\n");
-		goto errout;
+	for (i = 0; i < chip->num_streams; i++) {
+		/* allocate memory for the BDL for each stream */
+		err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
+					  snd_dma_pci_data(chip->pci),
+					  BDL_SIZE, &chip->azx_dev[i].bdl);
+		if (err < 0) {
+			snd_printk(KERN_ERR SFX "cannot allocate BDL\n");
+			goto errout;
+		}
 	}
 	/* allocate memory for the position buffer */
 	err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,