[U-Boot] [PATCH] ARM926ejs: Add routines to invalidate D-Cache

Hong Xu
2011-08-09T01:57:41Z

Hi Marek Vasut,

On 08/09/2011 01:34 AM, Marek Vasut wrote:
> On Monday, August 08, 2011 10:01:19 AM Albert ARIBAUD wrote:
>> Hi Hong Xu,
>>
>> Le 08/08/2011 05:20, Hong Xu a ?crit :
>>> After DMA operation, we need to maintain D-Cache coherency.
>>> So that the DCache must be invalidated (hence CPU will fetch
>>> data written by DMA controller from RAM).
>>>
>>> Tested on AT91SAM9261EK with Peripheral DMA controller.
>>>
>>> Signed-off-by: Hong Xu<hong.xu@atmel.com>
>>> Tested-by: Elen Song<elen.song@atmel.com>
>>> CC: Albert Aribaud<albert.u.boot@aribaud.net>
>>> CC: Aneesh V<aneesh@ti.com>
>>> CC: Reinhard Meyer<u-boot@emk-elektronik.de>
>>> CC: Heiko Schocher<hs@denx.de>
>>> ---
>>>
>>> V2:
>>> Per Albert's suggestion, add invalidate_dcache_range
>>>
>>> V3:
>>> invalidate_dcache_range emits warning when detecting unaligned buffer
>>>
>>> invalidate_dcache_range won't clean any adjacent cache line when
>>> detecting unaligned buffer and only round up/down the buffer address
>>>
>>> + mva = start;
>>> + if ((mva& (cache_line_len - 1)) != 0) {
>>> + printf("WARNING: %s - unaligned buffer detected, starting "
>>
>> I'd rather have a message about "cache", not "buffer", e.g.
>>
>> printf("WARNING: %s - start address %x is not aligned\n"
>> __FUNCTION__, start);
>
> __func__ is prefered in linux kernel :-)

__func__ is C99 standard. __FUNCTION__ appears more in U-Boot. ;-)
GCC manual says some older GCC only recognize __FUNCTION__ .
If we rely on GCC, it looks __FUNCTION__ will reduce troubles.

BR,
Eric

>>
>>> + mva&= ~(cache_line_len - 1);
>>> + }
>>> + if ((stop& (cache_line_len - 1)) != 0) {
>>> + printf("WARNING: %s - unaligned buffer detected, ending "
>>> + "address: 0x%08x\n", __FUNCTION__, stop);
>>
>> Ditto.
>
> Ditto.
> …