Lately, i use i.MX RT1052 to develpe a product, i use cache to improve performance.But when i use the speed_test() function to test the cache performance,the code is executed in ITCM,i find that when i enable D-cache with the adram (0x80000000,2MB)memory default configuration cacheable/WT(no WA),the speed is the faster than i disable the cache.According to my understanding,WT is a write updates both the cache and the external memory system,enable and disable the cache does not affect data access speed,so why?when i enable the D-cache,i configure the adram (0x80000000,2MB)memory cache/WB(no WA),i find the cache/WT(no WA) and cache/WB(no WA) speed is same.so why?
uint32_t AudioInData = 0;
void speed_test(void)
{
uint32_t i = 0 , j = 0;
for(i=0;i<30000;i++)
{
for(j=0;j<30000;j++)
{
AudioInData += 0xA5A5;
}
}
}
,
