[U-Boot] [UBOOT RFC PATCH 13/13] dwc3: core: Change the bounce buffer size to 4096

Kishon Vijay Abraham I
2014-08-22T11:02:10Z

Hi,

On Tuesday 19 August 2014 09:57 PM, Felipe Balbi wrote:
> On Tue, Aug 19, 2014 at 09:45:11PM +0530, Kishon Vijay Abraham I wrote:
>> Hi,
>>
>> On Monday 18 August 2014 08:11 PM, Felipe Balbi wrote:
>>> On Mon, Aug 18, 2014 at 07:58:35PM +0530, Kishon Vijay Abraham I wrote:
>>>> Bounce buffer is used for transferring requests which is not maxpacket
>>>> aligned. In the case of DFU the requests can be upto 4096 bytes.
>>>>
>>>> While the actual fix for this should be using two chained TRBs to handle
>>>> the transfer, this can be used as a temporary fix.
>>>
>>> Did you manage to trigger this fault ? Was the size larger than 512 ?
>>
>> yeah.. transferring any kernel image resulted in a size larger than 512.
>
> but it's also larger than 4KiB :-)

Yeah. But the DFU specifies the maximum transfer size in wTransferSize (DFU
function descriptor) to the host which is 4096 bytes (DFU_USB_BUFSIZ).

So the max size will be only 4KB.

Thanks
Kishon