[PATCH 0/8] Add and implement gen_pool_dma_alloc()

[PATCH 0/8] Add and implement gen_pool_dma_alloc()

[Nicolin Chen]

Previously, we don't have a specific gen_pool_alloc() for DMA usage;
Instead, we need to use gen_pool_virt_to_phys() to convert the addr
returned from gen_pool_alloc(). So each implementation of this has
duplicated code. Thus add new helper function -- gen_pool_dma_alloc().

After gen_pool_dma_alloc() is introduced, we can replace the original
combination of gen_pool_alloc()+gen_pool_virt_to_phys() with this new
helper function. Thus this patch implement the helper function to all
the current drivers which use gen_pool_virt_to_phys().

!!-------------------important------------------!!

The later 7 patches need all related driver owner to test. We can
here define a simple rule:
1, If one driver owner or maintainer doesn't like the mofication
   to his/her driver, just let me know. I would drop that patch.
2, If there's a bug and issue found after patch-testing, please
   reply the mail so that I can fix and refine the patch.
3, If one driver owner or maintainer is too busy and doesn't have
   bandwidth to test the patch, I would drop that patch from this
   series. We can reimplement it till there's someone test it.

!!-------------------current progress-----------!!

  lib/genalloc: [Okay]
  ARM: davinci: [Untested]
  dma: mmp_tdma: [Untested]
  [media] coda: [Untested]
  uio: uio_pruss: [Untested]
  ALSA: memalloc: [Tested] by Nicolin Chen with i.MX6Q SabreSD
  ASoC: davinci: [Untested]
  ASoC: pxa: use [Untested]


Nicolin Chen (8):
  lib/genalloc: add a helper function for DMA buffer allocation
  ARM: davinci: use gen_pool_dma_alloc() to sram.c
  dma: mmp_tdma: use gen_pool_dma_alloc() to allocate descriptor
  [media] coda: use gen_pool_dma_alloc() to allocate iram buffer
  uio: uio_pruss: use gen_pool_dma_alloc() to allocate sram memory
  ALSA: memalloc: use gen_pool_dma_alloc() to allocate iram buffer
  ASoC: davinci: use gen_pool_dma_alloc() in davinci-pcm.c
  ASoC: pxa: use gen_pool_dma_alloc() to allocate dma buffer

 arch/arm/mach-davinci/sram.c    |  9 +--------
 drivers/dma/mmp_tdma.c          |  7 +------
 drivers/media/platform/coda.c   |  5 ++---
 drivers/uio/uio_pruss.c         |  6 ++----
 include/linux/genalloc.h        |  2 ++
 lib/genalloc.c                  | 28 ++++++++++++++++++++++++++++
 sound/core/memalloc.c           |  6 +-----
 sound/soc/davinci/davinci-pcm.c |  3 +--
 sound/soc/pxa/mmp-pcm.c         |  3 +--
 9 files changed, 39 insertions(+), 30 deletions(-)

-- 
1.8.4

[PATCH 1/8] lib/genalloc: add a helper function for DMA buffer allocation

[Nicolin Chen]

When using pool space for DMA buffer, there might be duplicated calling
of gen_pool_alloc() and gen_pool_virt_to_phys() in each implementation.

Thus it's better to add a simple helper function, a compatible one to
the common dma_alloc_coherent(), to save some code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 include/linux/genalloc.h |  2 ++
 lib/genalloc.c           | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index f8d41cb..1eda33d 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -94,6 +94,8 @@ static inline int gen_pool_add(struct gen_pool *pool, unsigned long addr,
 }
 extern void gen_pool_destroy(struct gen_pool *);
 extern unsigned long gen_pool_alloc(struct gen_pool *, size_t);
+extern void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size,
+		dma_addr_t *dma);
 extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
 extern void gen_pool_for_each_chunk(struct gen_pool *,
 	void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 26cf20b..dda3116 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -313,6 +313,34 @@ retry:
 EXPORT_SYMBOL(gen_pool_alloc);
 
 /**
+ * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: dma-view physical address
+ *
+ * Allocate the requested number of bytes from the specified pool.
+ * Uses the pool allocation function (with first-fit algorithm by default).
+ * Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ */
+void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
+{
+	unsigned long vaddr;
+
+	if (!pool)
+		return NULL;
+
+	vaddr = gen_pool_alloc(pool, size);
+	if (!vaddr)
+		return NULL;
+
+	*dma = gen_pool_virt_to_phys(pool, vaddr);
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc);
+
+/**
  * gen_pool_free - free allocated special memory back to the pool
  * @pool: pool to free to
  * @addr: starting address of memory to free back to pool
-- 
1.8.4

[PATCH 2/8] ARM: davinci: use gen_pool_dma_alloc() to sram.c

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 arch/arm/mach-davinci/sram.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/arm/mach-davinci/sram.c b/arch/arm/mach-davinci/sram.c
index f18928b..8540ddd 100644
--- a/arch/arm/mach-davinci/sram.c
+++ b/arch/arm/mach-davinci/sram.c
@@ -25,7 +25,6 @@ struct gen_pool *sram_get_gen_pool(void)
 
 void *sram_alloc(size_t len, dma_addr_t *dma)
 {
-	unsigned long vaddr;
 	dma_addr_t dma_base = davinci_soc_info.sram_dma;
 
 	if (dma)
@@ -33,13 +32,7 @@ void *sram_alloc(size_t len, dma_addr_t *dma)
 	if (!sram_pool || (dma && !dma_base))
 		return NULL;
 
-	vaddr = gen_pool_alloc(sram_pool, len);
-	if (!vaddr)
-		return NULL;
-
-	if (dma)
-		*dma = gen_pool_virt_to_phys(sram_pool, vaddr);
-	return (void *)vaddr;
+	return gen_pool_dma_alloc(sram_pool, len, dma);
 
 }
 EXPORT_SYMBOL(sram_alloc);
-- 
1.8.4

[PATCH 3/8] dma: mmp_tdma: use gen_pool_dma_alloc() to allocate descriptor

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 drivers/dma/mmp_tdma.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/dma/mmp_tdma.c b/drivers/dma/mmp_tdma.c
index 2b4026d..3ddacc1 100644
--- a/drivers/dma/mmp_tdma.c
+++ b/drivers/dma/mmp_tdma.c
@@ -378,12 +378,7 @@ struct mmp_tdma_desc *mmp_tdma_alloc_descriptor(struct mmp_tdma_chan *tdmac)
 	if (!gpool)
 		return NULL;
 
-	tdmac->desc_arr = (void *)gen_pool_alloc(gpool, size);
-	if (!tdmac->desc_arr)
-		return NULL;
-
-	tdmac->desc_arr_phys = gen_pool_virt_to_phys(gpool,
-			(unsigned long)tdmac->desc_arr);
+	tdmac->desc_arr = gen_pool_dma_alloc(gpool, size, &tdmac->desc_arr_phys);
 
 	return tdmac->desc_arr;
 }
-- 
1.8.4

[PATCH 4/8] [media] coda: use gen_pool_dma_alloc() to allocate iram buffer

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 drivers/media/platform/coda.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/coda.c b/drivers/media/platform/coda.c
index ed4998c..bd72fb9 100644
--- a/drivers/media/platform/coda.c
+++ b/drivers/media/platform/coda.c
@@ -3298,13 +3298,12 @@ static int coda_probe(struct platform_device *pdev)
 		dev->iram_size = CODA7_IRAM_SIZE;
 		break;
 	}
-	dev->iram_vaddr = gen_pool_alloc(dev->iram_pool, dev->iram_size);
+	dev->iram_vaddr = (unsigned long)gen_pool_dma_alloc(dev->iram_pool,
+			dev->iram_size, (dma_addr_t *)&dev->iram_paddr);
 	if (!dev->iram_vaddr) {
 		dev_err(&pdev->dev, "unable to alloc iram\n");
 		return -ENOMEM;
 	}
-	dev->iram_paddr = gen_pool_virt_to_phys(dev->iram_pool,
-						dev->iram_vaddr);
 
 	platform_set_drvdata(pdev, dev);
 
-- 
1.8.4

[PATCH 5/8] uio: uio_pruss: use gen_pool_dma_alloc() to allocate sram memory

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 drivers/uio/uio_pruss.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/uio/uio_pruss.c b/drivers/uio/uio_pruss.c
index f519da9..96c4a19 100644
--- a/drivers/uio/uio_pruss.c
+++ b/drivers/uio/uio_pruss.c
@@ -158,14 +158,12 @@ static int pruss_probe(struct platform_device *dev)
 	if (pdata->sram_pool) {
 		gdev->sram_pool = pdata->sram_pool;
 		gdev->sram_vaddr =
-			gen_pool_alloc(gdev->sram_pool, sram_pool_sz);
+			(unsigned long)gen_pool_dma_alloc(gdev->sram_pool,
+					sram_pool_sz, &gdev->sram_paddr);
 		if (!gdev->sram_vaddr) {
 			dev_err(&dev->dev, "Could not allocate SRAM pool\n");
 			goto out_free;
 		}
-		gdev->sram_paddr =
-			gen_pool_virt_to_phys(gdev->sram_pool,
-					      gdev->sram_vaddr);
 	}
 
 	gdev->ddr_vaddr = dma_alloc_coherent(&dev->dev, extram_pool_sz,
-- 
1.8.4

[PATCH 6/8] ALSA: memalloc: use gen_pool_dma_alloc() to allocate iram buffer

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 sound/core/memalloc.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c
index 9d93f02..5e1c7bc 100644
--- a/sound/core/memalloc.c
+++ b/sound/core/memalloc.c
@@ -184,11 +184,7 @@ static void snd_malloc_dev_iram(struct snd_dma_buffer *dmab, size_t size)
 	/* Assign the pool into private_data field */
 	dmab->private_data = pool;
 
-	dmab->area = (void *)gen_pool_alloc(pool, size);
-	if (!dmab->area)
-		return;
-
-	dmab->addr = gen_pool_virt_to_phys(pool, (unsigned long)dmab->area);
+	dmab->area = gen_pool_dma_alloc(pool, size, &dmab->addr);
 }
 
 /**
-- 
1.8.4

[PATCH 7/8] ASoC: davinci: use gen_pool_dma_alloc() in davinci-pcm.c

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 sound/soc/davinci/davinci-pcm.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/sound/soc/davinci/davinci-pcm.c b/sound/soc/davinci/davinci-pcm.c
index 84a63c6..fa64cd8 100644
--- a/sound/soc/davinci/davinci-pcm.c
+++ b/sound/soc/davinci/davinci-pcm.c
@@ -267,10 +267,9 @@ static int allocate_sram(struct snd_pcm_substream *substream,
 		return 0;
 
 	ppcm->period_bytes_max = size;
-	iram_virt = (void *)gen_pool_alloc(sram_pool, size);
+	iram_virt = gen_pool_dma_alloc(sram_pool, size, &iram_phys);
 	if (!iram_virt)
 		goto exit1;
-	iram_phys = gen_pool_virt_to_phys(sram_pool, (unsigned)iram_virt);
 	iram_dma = kzalloc(sizeof(*iram_dma), GFP_KERNEL);
 	if (!iram_dma)
 		goto exit2;
-- 
1.8.4

[PATCH 8/8] ASoC: pxa: use gen_pool_dma_alloc() to allocate dma buffer

[Nicolin Chen]

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.

Signed-off-by: Nicolin Chen <b42378@freescale.com>
---
 sound/soc/pxa/mmp-pcm.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/sound/soc/pxa/mmp-pcm.c b/sound/soc/pxa/mmp-pcm.c
index 8235e23..7929e19 100644
--- a/sound/soc/pxa/mmp-pcm.c
+++ b/sound/soc/pxa/mmp-pcm.c
@@ -201,10 +201,9 @@ static int mmp_pcm_preallocate_dma_buffer(struct snd_pcm_substream *substream,
 	if (!gpool)
 		return -ENOMEM;
 
-	buf->area = (unsigned char *)gen_pool_alloc(gpool, size);
+	buf->area = gen_pool_dma_alloc(gpool, size, &buf->addr);
 	if (!buf->area)
 		return -ENOMEM;
-	buf->addr = gen_pool_virt_to_phys(gpool, (unsigned long)buf->area);
 	buf->bytes = size;
 	return 0;
 }
-- 
1.8.4