Jetpack/kernel/kernel-4.9/lib/check_signature.c

27 lines
599 B
C

#include <linux/io.h>
#include <linux/export.h>
/**
* check_signature - find BIOS signatures
* @io_addr: mmio address to check
* @signature: signature block
* @length: length of signature
*
* Perform a signature comparison with the mmio address io_addr. This
* address should have been obtained by ioremap.
* Returns 1 on a match.
*/
int check_signature(const volatile void __iomem *io_addr,
const unsigned char *signature, int length)
{
while (length--) {
if (readb(io_addr) != *signature)
return 0;
io_addr++;
signature++;
}
return 1;
}
EXPORT_SYMBOL(check_signature);