Commit 42e748a0 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: memalloc: Add non-cached buffer type 



In some cases (mainly for x86), we need the DMA coherent buffer with
non-cached pages.  Although this has been done in each driver side
like HD-audio and intel8x0, it can be done cleaner in the core memory
allocator.

This patch adds the new types, SNDRV_DMA_TYPE_DEV_UC and
SNDRV_DMA_TYPE_DEV_UC_SG, for allocating such non-cached buffer
pages.  On non-x86 architectures, they work as same as the standard
SNDRV_DMA_TYPE_DEV and *_SG.

One additional change by this move is that we can assure to pass the
non-cached pgprot to the vmapped buffer, too.  It eventually fixes the
case like non-snoop mode without mmap access on HD-audio.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 28f3f4f6

include/sound/memalloc.h

+3 −0
Original line number Diff line number Diff line
@@ -47,10 +47,13 @@ struct snd_dma_device { 
#define SNDRV_DMA_TYPE_UNKNOWN		0	/* not defined */

#define SNDRV_DMA_TYPE_CONTINUOUS	1	/* continuous no-DMA memory */

#define SNDRV_DMA_TYPE_DEV		2	/* generic device continuous */

#define SNDRV_DMA_TYPE_DEV_UC		5	/* continuous non-cahced */

#ifdef CONFIG_SND_DMA_SGBUF

#define SNDRV_DMA_TYPE_DEV_SG		3	/* generic device SG-buffer */

#define SNDRV_DMA_TYPE_DEV_UC_SG	6	/* SG non-cached */

#else

#define SNDRV_DMA_TYPE_DEV_SG	SNDRV_DMA_TYPE_DEV /* no SG-buf support */

#define SNDRV_DMA_TYPE_DEV_UC_SG	SNDRV_DMA_TYPE_DEV_UC

#endif

#ifdef CONFIG_GENERIC_ALLOCATOR

#define SNDRV_DMA_TYPE_DEV_IRAM		4	/* generic device iram-buffer */

sound/core/memalloc.c

+17 −0
Original line number Diff line number Diff line
@@ -25,6 +25,9 @@ 
#include <linux/mm.h>

#include <linux/dma-mapping.h>

#include <linux/genalloc.h>

#ifdef CONFIG_X86

#include <asm/set_memory.h>

#endif

#include <sound/memalloc.h>



/*
@@ -92,11 +95,21 @@ static void snd_malloc_dev_pages(struct snd_dma_buffer *dmab, size_t size) 
		| __GFP_NOWARN; /* no stack trace print - this call is non-critical */

	dmab->area = dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr,

					gfp_flags);

#ifdef CONFIG_X86

	if (dmab->area && dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)

		set_memory_wc((unsigned long)dmab->area,

			      PAGE_ALIGN(size) >> PAGE_SHIFT);

#endif

}



/* free the coherent DMA pages */

static void snd_free_dev_pages(struct snd_dma_buffer *dmab)

{

#ifdef CONFIG_X86

	if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)

		set_memory_wb((unsigned long)dmab->area,

			      PAGE_ALIGN(dmab->bytes) >> PAGE_SHIFT);

#endif

	dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);

}
@@ -191,11 +204,13 @@ int snd_dma_alloc_pages(int type, struct device *device, size_t size, 
		dmab->dev.type = SNDRV_DMA_TYPE_DEV;

#endif /* CONFIG_GENERIC_ALLOCATOR */

	case SNDRV_DMA_TYPE_DEV:

	case SNDRV_DMA_TYPE_DEV_UC:

		snd_malloc_dev_pages(dmab, size);

		break;

#endif

#ifdef CONFIG_SND_DMA_SGBUF

	case SNDRV_DMA_TYPE_DEV_SG:

	case SNDRV_DMA_TYPE_DEV_UC_SG:

		snd_malloc_sgbuf_pages(device, size, dmab, NULL);

		break;

#endif
@@ -266,11 +281,13 @@ void snd_dma_free_pages(struct snd_dma_buffer *dmab) 
		break;

#endif /* CONFIG_GENERIC_ALLOCATOR */

	case SNDRV_DMA_TYPE_DEV:

	case SNDRV_DMA_TYPE_DEV_UC:

		snd_free_dev_pages(dmab);

		break;

#endif

#ifdef CONFIG_SND_DMA_SGBUF

	case SNDRV_DMA_TYPE_DEV_SG:

	case SNDRV_DMA_TYPE_DEV_UC_SG:

		snd_free_sgbuf_pages(dmab);

		break;

#endif

sound/core/sgbuf.c

+13 −2
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 
#include <linux/mm.h>

#include <linux/vmalloc.h>

#include <linux/export.h>

#include <asm/pgtable.h>

#include <sound/memalloc.h>
@@ -43,6 +44,8 @@ int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab) 
	dmab->area = NULL;



	tmpb.dev.type = SNDRV_DMA_TYPE_DEV;

	if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC_SG)

		tmpb.dev.type = SNDRV_DMA_TYPE_DEV_UC;

	tmpb.dev.dev = sgbuf->dev;

	for (i = 0; i < sgbuf->pages; i++) {

		if (!(sgbuf->table[i].addr & ~PAGE_MASK))
@@ -72,12 +75,20 @@ void *snd_malloc_sgbuf_pages(struct device *device, 
	struct snd_dma_buffer tmpb;

	struct snd_sg_page *table;

	struct page **pgtable;

	int type = SNDRV_DMA_TYPE_DEV;

	pgprot_t prot = PAGE_KERNEL;



	dmab->area = NULL;

	dmab->addr = 0;

	dmab->private_data = sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);

	if (! sgbuf)

		return NULL;

	if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC_SG) {

		type = SNDRV_DMA_TYPE_DEV_UC;

#ifdef pgprot_noncached

		prot = pgprot_noncached(PAGE_KERNEL);

#endif

	}

	sgbuf->dev = device;

	pages = snd_sgbuf_aligned_pages(size);

	sgbuf->tblsize = sgbuf_align_table(pages);
@@ -98,7 +109,7 @@ void *snd_malloc_sgbuf_pages(struct device *device, 
		if (chunk > maxpages)

			chunk = maxpages;

		chunk <<= PAGE_SHIFT;

		if (snd_dma_alloc_pages_fallback(SNDRV_DMA_TYPE_DEV, device,

		if (snd_dma_alloc_pages_fallback(type, device,

						 chunk, &tmpb) < 0) {

			if (!sgbuf->pages)

				goto _failed;
@@ -125,7 +136,7 @@ void *snd_malloc_sgbuf_pages(struct device *device, 
	}



	sgbuf->size = size;

	dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, PAGE_KERNEL);

	dmab->area = vmap(sgbuf->page_table, sgbuf->pages, VM_MAP, prot);

	if (! dmab->area)

		goto _failed;

	if (res_size)

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