coreboot-kgpe-d16/src/arch/x86/cbmem.c

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/*
* This file is part of the coreboot project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <stdlib.h>
#include <cbmem.h>
#include <arch/acpi.h>
#if IS_ENABLED(CONFIG_LATE_CBMEM_INIT)
void __weak backup_top_of_low_cacheable(uintptr_t ramtop)
{
/* Do nothing. Chipset may have implementation to save ramtop in NVRAM.
*/
}
uintptr_t __weak restore_top_of_low_cacheable(void)
{
return 0;
}
#endif /* LATE_CBMEM_INIT */
#if IS_ENABLED(CONFIG_CBMEM_TOP_BACKUP)
static void *cbmem_top_backup;
void set_late_cbmem_top(uintptr_t ramtop)
{
backup_top_of_low_cacheable(ramtop);
if (ENV_RAMSTAGE)
cbmem_top_backup = (void *)ramtop;
}
/* Top of CBMEM is at highest usable DRAM address below 4GiB. */
uintptr_t __weak restore_cbmem_top(void)
{
if (IS_ENABLED(CONFIG_LATE_CBMEM_INIT) && ENV_ROMSTAGE)
if (!acpi_is_wakeup_s3())
return 0;
return restore_top_of_low_cacheable();
}
void *cbmem_top(void)
{
uintptr_t top_backup;
if (ENV_RAMSTAGE && cbmem_top_backup != NULL)
return cbmem_top_backup;
top_backup = restore_cbmem_top();
if (ENV_RAMSTAGE)
cbmem_top_backup = (void *)top_backup;
return (void *)top_backup;
}
#endif /* CBMEM_TOP_BACKUP */
/* Something went wrong, our high memory area got wiped */
void cbmem_fail_resume(void)
{
#if !defined(__PRE_RAM__) && IS_ENABLED(CONFIG_HAVE_ACPI_RESUME)
/* ACPI resume needs to be cleared in the fail-to-recover case, but that
* condition is only handled during ramstage. */
acpi_fail_wakeup();
#endif
}