diff --git a/uboot-compiler/shmbuffer/main b/uboot-compiler/shmbuffer/main new file mode 100755 index 0000000000000000000000000000000000000000..d1a549d6ca963e6a11aeb791da7697669ee3c981 Binary files /dev/null and b/uboot-compiler/shmbuffer/main differ diff --git a/uboot-compiler/shmbuffer/main.c b/uboot-compiler/shmbuffer/main.c new file mode 100644 index 0000000000000000000000000000000000000000..0aadcad4556e27fc1e811633093028f0ad685a81 --- /dev/null +++ b/uboot-compiler/shmbuffer/main.c @@ -0,0 +1,31 @@ +#include<stdio.h> +#include<stddef.h> +#include<sys/mman.h> +#include<fcntl.h> + +#define SHMADDR 0x3F000000 + +int main(int argc, char *argv[]) +{ + int fd; + int * memaddr; + + fd = open("/dev/mem", O_RDWR); + + if (fd == -1) + { + printf("can not access /dev/mem\n" ); + return -1; + } + + memaddr = + (int*)mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, fd, SHMADDR); + if (memaddr == MAP_FAILED) + { + printf("mmap failed\n" ); + return -1; + } + printf("value=%d\n", *memaddr); + + +} \ No newline at end of file