Subject: [PATCH 1/2] ARM: mx27_3ds: Reserve memory for camera usage

From: [email-masked] (Gaëtan Carlier)
Date: Wed, 10 Oct 2012 08:51:00 +0200

Hi Fabio,
On 10/10/2012 05:29 AM, Fabio Estevam wrote:
> From: Fabio Estevam <[email-masked]>
>
> Reserve dedicated memory block for camera usage.
Why camera need to have a dedicated memory block reserved in the 
platform file ?
>
> Signed-off-by: Fabio Estevam <[email-masked]>
> ---
>   arch/arm/mach-imx/mach-mx27_3ds.c |   32 +++++++++++++++++++++++++++++++-
>   1 file changed, 31 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/mach-imx/mach-mx27_3ds.c b/arch/arm/mach-imx/mach-mx27_3ds.c
> index 05996f3..d3b9a60 100644
> --- a/arch/arm/mach-imx/mach-mx27_3ds.c
> +++ b/arch/arm/mach-imx/mach-mx27_3ds.c
> @@ -30,6 +30,7 @@
>   #include <linux/spi/spi.h>
>   #include <linux/regulator/machine.h>
>   #include <linux/spi/l4f00242t03.h>
> +#include <asm/memblock.h>
>
>   #include <media/soc_camera.h>
>
> @@ -165,6 +166,9 @@ static const int mx27pdk_pins[] __initconst = {
>   	PC19_PF_SSI4_CLK,
>   };
>
> +static phys_addr_t mx2_camera_base __initdata;
> +#define MX27PDK_CAM_BUF_SIZE	SZ_8M
> +
>   static struct gpio mx27_3ds_camera_gpios[] = {
>   	{ CSI_PWRDWN, GPIOF_OUT_INIT_HIGH, "camera-power" },
>   	{ CSI_RESET, GPIOF_OUT_INIT_HIGH, "camera-reset" },
> @@ -478,6 +482,24 @@ static const struct mx2_camera_platform_data mx27_3ds_cam_pdata __initconst = {
>   	.clk = 26000000,
>   };
>
> +static void __init mx27pdk_init_camera(void)
> +{
> +	struct platform_device *pdev;
> +	int dma;
> +
> +	pdev = imx27_add_mx2_camera(&mx27_3ds_cam_pdata);
> +
> +	if (IS_ERR(pdev))
> +		return;
> +
> +	dma = dma_declare_coherent_memory(&pdev->dev,
> +				mx2_camera_base, mx2_camera_base,
> +				MX27PDK_CAM_BUF_SIZE,
> +				DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE);
> +	if (!(dma & DMA_MEMORY_MAP))
> +		return;
> +}
> +
>   static const struct imxi2c_platform_data mx27_3ds_i2c0_data __initconst = {
>   	.bitrate = 100000,
>   };
> @@ -527,7 +549,7 @@ static void __init mx27pdk_init(void)
>   		iclink_ov2640.power = NULL;
>   	}
>
> -	imx27_add_mx2_camera(&mx27_3ds_cam_pdata);
> +	mx27pdk_init_camera();
>   	imx27_add_imx_ssi(0, &mx27_3ds_ssi_pdata);
>
>   	imx_add_platform_device("imx_mc13783", 0, NULL, 0, NULL, 0);
> @@ -542,6 +564,13 @@ static struct sys_timer mx27pdk_timer = {
>   	.init	= mx27pdk_timer_init,
>   };
>
> +static void __init mx27pdk_reserve(void)
> +{
> +	/* reserve MX27_3DS_CAMERA_BUF_SIZE bytes for mx2-camera */
> +	mx2_camera_base = arm_memblock_steal(MX27PDK_CAM_BUF_SIZE,
> +						MX27PDK_CAM_BUF_SIZE);
> +}
> +
>   MACHINE_START(MX27_3DS, "Freescale MX27PDK")
>   	/* maintainer: Freescale Semiconductor, Inc. */
>   	.atag_offset = 0x100,
> @@ -551,5 +580,6 @@ MACHINE_START(MX27_3DS, "Freescale MX27PDK")
>   	.handle_irq = imx27_handle_irq,
>   	.timer = &mx27pdk_timer,
>   	.init_machine = mx27pdk_init,
> +	.reserve = mx27pdk_reserve,
>   	.restart	= mxc_restart,
>   MACHINE_END
>
Thank you.
Best regards,
Ga?tan Carlier.