[U-Boot] [PATCH 4/4] USB:gadget:designware Fix memory nonalignment issue

[Amit Virdi]

Dear Marek,

On 3/5/2012 11:51 PM, Marek Vasut wrote:
> Dear Amit Virdi,
>
>> From: Shiraz Hashim<shiraz.hashim at st.com>
>>
>> While receiving packets from FIFO sometimes the buffer provided was
>> nonaligned. Fix this by taking a temporary aligned buffer and then
>> copying the content to nonaligned buffer.
>>
>> Signed-off-by: Shiraz Hashim<shiraz.hashim at st.com>
>> Signed-off-by: Amit Virdi<amit.virdi at st.com>
>> ---
>>   drivers/usb/gadget/designware_udc.c |   15 ++++++++++++++-
>>   1 files changed, 14 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/usb/gadget/designware_udc.c
>> b/drivers/usb/gadget/designware_udc.c index d4b53a2..878123c 100644
>> --- a/drivers/usb/gadget/designware_udc.c
>> +++ b/drivers/usb/gadget/designware_udc.c
>> @@ -202,6 +202,7 @@ static int usbgetpckfromfifo(int epNum, u8 *bufp, u32
>> len) u32 i, nw, nb;
>>   	u32 *wrdp;
>>   	u8 *bytp;
>> +	u32 tmp[128];
>>
>>   	if (readl(&udc_regs_p->dev_stat)&  DEV_STAT_RXFIFO_EMPTY)
>>   		return -1;
>> @@ -209,7 +210,12 @@ static int usbgetpckfromfifo(int epNum, u8 *bufp, u32
>> len) nw = len / sizeof(u32);
>>   	nb = len % sizeof(u32);
>>
>> -	wrdp = (u32 *)bufp;
>> +	/* use tmp buf if bufp is not word aligned */
>> +	if ((int)bufp&  0x3)
>> +		wrdp = (u32 *)&tmp[0];
>> +	else
>> +		wrdp = (u32 *)bufp;
>> +
>>   	for (i = 0; i<  nw; i++) {
>>   		writel(readl(fifo_ptr), wrdp);
>>   		wrdp++;
>> @@ -223,6 +229,13 @@ static int usbgetpckfromfifo(int epNum, u8 *bufp, u32
>> len) }
>>   	readl(&outep_regs_p[epNum].write_done);
>>
>> +	/* copy back tmp buffer to bufp if bufp is not word aligned */
>> +	if ((int)bufp&  0x3) {
>> +		bytp = (u8 *)&tmp[0];
>> +		for (i = 0; i<  len; i++)
>> +			bufp[i] = bytp[i];
>> +	}
>> +
>>   	return 0;
>>   }
>
> This addresses EHCI cache problem, that's why you need bounce buffer, right?
>

No. The problem was we were copying data word-by-word to a non-word 
aligned memory in the USB gadget. So, this is different from the USB 
host controller issue.


Thanks n Regards
Amit Virdi

> This is the patch from Puneet, can you give it a go and tell me if EHCI works
> for you without 4/4 patch from your series or do you still see issues?
>
> http://permalink.gmane.org/gmane.comp.boot-loaders.u-boot/126447
>
> Thanks in advance!
>
> Best regards,
> Marek Vasut
> .
>