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Altera_Forum's avatar
Altera_Forum
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11 years ago

Very low speed of HPS after Preloader

I try insert next code for Altera examples in main(): volatile int i; for (i = 0; i < 800*1000*1000; i++) ; In SDRAM-variant work is greater than 2 min, in HelloWorld for FFFF0000-addresses ...
Altera_Forum's avatar
Altera_Forum
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11 years ago

At last I run my test on onboard Linux: add function code to HelloWorld example: 

void my_chk() {
  volatile int i = 0;
  for (; i < 800*1000*1000; i++) ;
}

On -o0 option a call has 8 seconds and 8 asm-commands in main cycle, on -o3 -- 7 sec and 6 "body" asm-commands.

The same code in Baremetal is runned 245 seconds, with -o3 optimisation slightly faster -- 230 sec.

Where in HWLIB is API to accelerate of HPS ? Which code may use ?