[U-Boot] [PATCH] usb: dwc2: Reduce data buffer size to 16kB

[Marek Vasut]

On 02/21/2018 10:48 AM, Alexey Brodkin wrote:
> If we use hardware with very small RAM (let's consider just a couple
> of hundreds of kB but not megabytes) it is not super convenient to lose
> 64kB for statically allocated bufer which most probably won't be used
> as big as it is. Typically we'll have much shorter data packages to
> excahnge and in the worst case longer packets will be split on separate
> transactions.
> 
> Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
> Cc: Marek Vasut <marex at denx.de>

I think it does make sense to make this configurable with 64 kiB as
default and tweak your platform to 16 kiB in it's defconfig.

> ---
>  drivers/usb/host/dwc2.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
> index 0efe645044c5..20cd4a6d3d55 100644
> --- a/drivers/usb/host/dwc2.c
> +++ b/drivers/usb/host/dwc2.c
> @@ -25,7 +25,7 @@ DECLARE_GLOBAL_DATA_PTR;
>  #define DWC2_HC_CHANNEL			0
>  
>  #define DWC2_STATUS_BUF_SIZE		64
> -#define DWC2_DATA_BUF_SIZE		(64 * 1024)
> +#define DWC2_DATA_BUF_SIZE		(16 * 1024)
>  
>  #define MAX_DEVICE			16
>  #define MAX_ENDPOINT			16
> 


-- 
Best regards,
Marek Vasut