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ARM: mx3/mx31moboard: properly allocate memory for mx3-camera 

It's not allowed to create an alias of system RAM for DMA.  So the memory
used must not be allocated using dma_alloc_coherent but has to be reserved
before using memblock routines.

There is no need to memzero the buffer because dma_alloc_coherent zeros
the memory for us.

LAKML-Reference: 1299271882-2130-4-git-send-email-u.kleine-koenig@pengutronix.de
Tested-by: Philippe Retornaz <philippe.retornaz@epfl.ch>
Acked-by: Philippe Retornaz <philippe.retornaz@epfl.ch>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Uwe Kleine-König 2011-03-03 14:21:53 +01:00 committed by Sascha Hauer
parent dca7c0b429
commit 031e912741
1 changed files with 17 additions and 16 deletions
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33
arch/arm/mach-mx3/mach-mx31moboard.c
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@ -27,6 +27,7 @@
#include <linux/mfd/mc13783.h>
#include <linux/spi/spi.h>
#include <linux/types.h>
#include <linux/memblock.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
@ -472,27 +473,17 @@ static struct mx3_camera_pdata camera_pdata = {
.mclk_10khz = 4800,
};
#define CAMERA_BUF_SIZE (4*1024*1024)
static phys_addr_t mx3_camera_base __initdata;
#define MX3_CAMERA_BUF_SIZE SZ_4M
static int __init mx31moboard_cam_alloc_dma(const size_t buf_size)
static int __init mx31moboard_cam_alloc_dma(void)
{
dma_addr_t dma_handle;
void *buf;
int dma;
if (buf_size < 2 * 1024 * 1024)
return -EINVAL;
buf = dma_alloc_coherent(NULL, buf_size, &dma_handle, GFP_KERNEL);
if (!buf) {
pr_err("%s: cannot allocate camera buffer-memory\n", __func__);
return -ENOMEM;
}
memset(buf, 0, buf_size);
dma = dma_declare_coherent_memory(&mx3_camera.dev,
dma_handle, dma_handle, buf_size,
mx3_camera_base, mx3_camera_base,
MX3_CAMERA_BUF_SIZE,
DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE);
/* The way we call dma_declare_coherent_memory only a malloc can fail */
@ -529,7 +520,7 @@ static void __init mx31moboard_init(void)
imx31_add_mxc_mmc(0, &sdhc1_pdata);
mxc_register_device(&mx3_ipu, &mx3_ipu_data);
if (!mx31moboard_cam_alloc_dma(CAMERA_BUF_SIZE))
if (!mx31moboard_cam_alloc_dma())
mxc_register_device(&mx3_camera, &camera_pdata);
usb_xcvr_reset();
@ -564,9 +555,19 @@ struct sys_timer mx31moboard_timer = {
.init = mx31moboard_timer_init,
};
static void __init mx31moboard_reserve(void)
{
/* reserve 4 MiB for mx3-camera */
mx3_camera_base = memblock_alloc(MX3_CAMERA_BUF_SIZE,
MX3_CAMERA_BUF_SIZE);
memblock_free(mx3_camera_base, MX3_CAMERA_BUF_SIZE);
memblock_remove(mx3_camera_base, MX3_CAMERA_BUF_SIZE);
}
MACHINE_START(MX31MOBOARD, "EPFL Mobots mx31moboard")
/* Maintainer: Valentin Longchamp, EPFL Mobots group */
.boot_params = MX3x_PHYS_OFFSET + 0x100,
.reserve = mx31moboard_reserve,
.map_io = mx31_map_io,
.init_early = imx31_init_early,
.init_irq = mx31_init_irq,