raspberry3_bare/hello.c

#include "fb.h"
#include "mbox.h"
#include "uart.h"
#include "utils.h"

struct fbst fb;
int kernelmain(void)
{
  init_uart();
  if (init_fb(&fb) == 0){
    puts("Fail to init framebuffer");
  }
  mbox[0] = 8 * 4;
  mbox[1] = MBOX_REQUEST;
  mbox[2] = MBOX_TAG_GETVCOREMEM;
  mbox[3] = 8;
  mbox[4] = 0;
  mbox[5] = 0;
  mbox[6] = 0;
  mbox[7] = MBOX_TAG_LAST;

  if (mbox_call(MBOX_CH_PROP, mbox)) {
    puts("videocore start at 0x");
    printhex(mbox[5]);
    puts(" - ");
    int mem = mbox[6] / 1024 / 1024;
    printdec(mem);
    puts(" Mo\n");
  } else {
    puts("Error getting videocore mem\n");
  }

    unsigned char *ptr=fb.fbp;

    for(int y=0; y<fb.height; y++) {
        for(int x=0; x<fb.width; x++) {
            if(y%60==0)
                *((unsigned int*)ptr)=0x00FF0000;
            else if (y%40==0)
                *((unsigned int*)ptr)=0x0000FF00;
            else if (y%20==0)
                *((unsigned int*)ptr)=0x000000FF;
            else
                *((unsigned int*)ptr)=0x00000000;
            ptr+=4;
        }
    }
  return 0;
}