coreboot-kgpe-d16/payloads/libpayload/arch/x86/boot_media.c

19 lines
568 B
C

/* SPDX-License-Identifier: BSD-3-Clause */
#include <arch/virtual.h>
#include <boot_device.h>
#include <commonlib/bsd/cb_err.h>
#include <stddef.h>
#include <string.h>
#include <sysinfo.h>
__attribute__((weak)) ssize_t boot_device_read(void *buf, size_t offset, size_t size)
{
/* Memory-mapping usually only works for the top 16MB. */
if (!lib_sysinfo.boot_media_size || lib_sysinfo.boot_media_size - offset > 16 * MiB)
return CB_ERR_ARG;
const void *const ptr = phys_to_virt(0 - lib_sysinfo.boot_media_size + offset);
memcpy(buf, ptr, size);
return size;
}