[U-Boot] [PATCH v5 3/7] dfu: mmc: file buffer: remove static allocation

[Lukasz Majewski <l.majewski@samsung.com>]

Hi Przemyslaw,

> For writing files, DFU implementation requires the file buffer
> with the len at least of file size. For big files it requires
> the same big buffer.
> 
> Previously the file buffer was allocated as a static variable,
> so it was a part of U-Boot .bss section. For 32MiB len of buffer
> we have 32MiB of additional space, required for this section.
> 
> The .bss needs to be cleared after the relocation.
> This introduces an additional boot delay at every start, but usually
> the dfu feature is not required at the standard boot, so the buffer
> should be allocated only if required.
> 
> This patch removes the static allocation of this buffer,
> and alloc it with memalign after first call of function:
> - dfu_fill_entity_mmc()
> and the buffer is freed on dfu_free_entity() call.
> 
> This was tested on Trats2.
> A quick test with trace. Boot time from start to main_loop() entry:
> - ~888ms - before this change (arch memset enabled for .bss clear)
> - ~464ms - after this change
> 
> Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> Cc: Lukasz Majewski <l.majewski@samsung.com>
> Cc: Stephen Warren <swarren@nvidia.com>
> Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
> Cc: Tom Rini <trini@ti.com>
> Cc: Marek Vasut <marek.vasut@gmail.com>
> 
> ---
> Changes V3, V4, V5
> - none
> ---
>  drivers/dfu/dfu_mmc.c | 25 ++++++++++++++++++++++---
>  1 file changed, 22 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/dfu/dfu_mmc.c b/drivers/dfu/dfu_mmc.c
> index 62d72fe..fd865e1 100644
> --- a/drivers/dfu/dfu_mmc.c
> +++ b/drivers/dfu/dfu_mmc.c
> @@ -16,8 +16,7 @@
>  #include <fat.h>
>  #include <mmc.h>
>  
> -static unsigned char __aligned(CONFIG_SYS_CACHELINE_SIZE)
> -
> dfu_file_buf[CONFIG_SYS_DFU_MAX_FILE_SIZE]; +static unsigned char
> *dfu_file_buf; static long dfu_file_buf_len;
>  
>  static int mmc_access_part(struct dfu_entity *dfu, struct mmc *mmc,
> int part) @@ -211,7 +210,7 @@ int dfu_flush_medium_mmc(struct
> dfu_entity *dfu) 
>  	if (dfu->layout != DFU_RAW_ADDR) {
>  		/* Do stuff here. */
> -		ret = mmc_file_op(DFU_OP_WRITE, dfu, &dfu_file_buf,
> +		ret = mmc_file_op(DFU_OP_WRITE, dfu, dfu_file_buf,
>  				&dfu_file_buf_len);
>  
>  		/* Now that we're done */
> @@ -263,6 +262,14 @@ int dfu_read_medium_mmc(struct dfu_entity *dfu,
> u64 offset, void *buf, return ret;
>  }
>  
> +void dfu_free_entity_mmc(struct dfu_entity *dfu)
> +{
> +	if (dfu_file_buf) {
> +		free(dfu_file_buf);
> +		dfu_file_buf = NULL;
> +	}
> +}
> +
>  /*
>   * @param s Parameter string containing space-separated arguments:
>   *	1st:
> @@ -370,6 +377,18 @@ int dfu_fill_entity_mmc(struct dfu_entity *dfu,
> char *devstr, char *s) dfu->write_medium = dfu_write_medium_mmc;
>  	dfu->flush_medium = dfu_flush_medium_mmc;
>  	dfu->inited = 0;
> +	dfu->free_entity = dfu_free_entity_mmc;
> +
> +	/* Check if file buffer is ready */
> +	if (!dfu_file_buf) {
> +		dfu_file_buf = memalign(CONFIG_SYS_CACHELINE_SIZE,
> +
> CONFIG_SYS_DFU_MAX_FILE_SIZE);
> +		if (!dfu_file_buf) {
> +			error("Could not memalign 0x%x bytes",
> +			      CONFIG_SYS_DFU_MAX_FILE_SIZE);
> +			return -ENOMEM;
> +		}
> +	}
>  
>  	return 0;
>  }

Acked-by: Lukasz Majewski <l.majewski@samsung.com>

-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group