len0rd/rockbox
1
0
Fork 1
mirror of https://github.com/Rockbox/rockbox.git synced 2025-11-15 08:02:34 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

imx233: make sure dma descriptors are cache friendly

Browse source 
Because DMA descriptors needs to be committed and discarded from
the cache, if they are not cache aligned and/or if their size
is not a multiple of cache ligne, nasty side effects could occur
with adjacents data. The same applies to DMA buffers which are
still potentially broken. Add a macro to ensure that these
constraints will not break by error in the future.

Change-Id: I1dd69a5a9c29796c156d953eaa57c0d281e79846
This commit is contained in:
Amaury Pouly 2012-05-20 01:23:17 +02:00
parent 1adc474771
commit 1b6e8cba62
5 changed files with 34 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

19
firmware/target/arm/imx233/pcm-imx233.c
View file

@ -26,8 +26,17 @@
#include "pcm-internal.h"
#include "audioout-imx233.h"
struct pcm_dma_command_t
{
struct apb_dma_command_t dma;
/* padded to next multiple of cache line size (32 bytes) */
uint32_t pad[5];
} __attribute__((packed)) CACHEALIGN_ATTR;
__ENSURE_STRUCT_CACHE_FRIENDLY(struct pcm_dma_command_t)
static int locked = 0;
static struct apb_dma_command_t dac_dma;
static struct pcm_dma_command_t dac_dma;
static bool pcm_freezed = false;
/**
@ -37,14 +46,14 @@ static bool pcm_freezed = false;
static void play(const void *addr, size_t size)
{
dac_dma.next = NULL;
dac_dma.buffer = (void *)addr;
dac_dma.cmd = HW_APB_CHx_CMD__COMMAND__READ |
dac_dma.dma.next = NULL;
dac_dma.dma.buffer = (void *)addr;
dac_dma.dma.cmd = HW_APB_CHx_CMD__COMMAND__READ |
HW_APB_CHx_CMD__IRQONCMPLT |
HW_APB_CHx_CMD__SEMAPHORE |
size << HW_APB_CHx_CMD__XFER_COUNT_BP;
/* dma subsystem will make sure cached stuff is written to memory */
imx233_dma_start_command(APB_AUDIO_DAC, &dac_dma);
imx233_dma_start_command(APB_AUDIO_DAC, &dac_dma.dma);
}
void INT_DAC_DMA(void)