linux-mips
[Top] [All Lists]

[PATCH 4/5] ALSA: pcm - fix page conversion on non-coherent PPC arch

To: alsa-devel@alsa-project.org
Subject: [PATCH 4/5] ALSA: pcm - fix page conversion on non-coherent PPC arch
From: Takashi Iwai <tiwai@suse.de>
Date: Thu, 26 Nov 2009 16:13:07 +0100
Cc: Ralf Baechle <ralf@linux-mips.org>, Wu Zhangjin <wuzhangjin@gmail.com>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, linux-mips@linux-mips.org, Benjamin Herrenschmidt <benh@kernel.crashing.org>, Kumar Gala <galak@gate.crashing.org>, Becky Bruce <beckyb@kernel.crashing.org>, Takashi Iwai <tiwai@suse.de>
In-reply-to: <1259248388-20095-4-git-send-email-tiwai@suse.de>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <1259248388-20095-1-git-send-email-tiwai@suse.de> <1259248388-20095-2-git-send-email-tiwai@suse.de> <1259248388-20095-3-git-send-email-tiwai@suse.de> <1259248388-20095-4-git-send-email-tiwai@suse.de>
Sender: linux-mips-bounce@linux-mips.org
The non-cohernet PPC arch doesn't give the correct address by a simple
virt_to_page() for pages allocated via dma_alloc_coherent().
This patch adds a hack to fix the conversion similarly like MIPS.

Note that this doesn't fix perfectly: the pages should be marked with
proper pgprot value.  This will be done in a future implementation like
the conversion to dma_mmap_coherent().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/core/pcm_native.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index e48c5f6..76eb763 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3070,6 +3070,16 @@ snd_pcm_default_page_ops(struct snd_pcm_substream 
*substream, unsigned long ofs)
        if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
                return virt_to_page(CAC_ADDR(vaddr));
 #endif
+#if defined(CONFIG_PPC32) && defined(CONFIG_NOT_COHERENT_CACHE)
+       if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) {
+               dma_addr_t addr = substream->runtime->dma_addr + ofs;
+               addr -= get_dma_offset(substream->dma_buffer.dev.dev);
+               /* assume dma_handle set via pfn_to_phys() in
+                * mm/dma-noncoherent.c
+                */
+               return pfn_to_page(dma_handle >> PAGE_SHIFT);
+       }
+#endif
        return virt_to_page(vaddr);
 }
 
-- 
1.6.5.3


<Prev in Thread] Current Thread [Next in Thread>