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Diffstat (limited to 'arch/x86/include/asm/cmos_layout.h')
| -rw-r--r-- | arch/x86/include/asm/cmos_layout.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cmos_layout.h b/arch/x86/include/asm/cmos_layout.h new file mode 100644 index 0000000000..0a0a51e72d --- /dev/null +++ b/arch/x86/include/asm/cmos_layout.h @@ -0,0 +1,31 @@ +/* + * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __CMOS_LAYOUT_H +#define __CMOS_LAYOUT_H + +/* + * The RTC internal registers and RAM is organized as two banks of 128 bytes + * each, called the standard and extended banks. The first 14 bytes of the + * standard bank contain the RTC time and date information along with four + * registers, A - D, that are used for configuration of the RTC. The extended + * bank contains a full 128 bytes of battery backed SRAM. + * + * For simplicity in U-Boot we only support CMOS in the standard bank, and + * its base address starts from offset 0x10, which leaves us 112 bytes space. + */ +#define CMOS_BASE 0x10 + +/* + * The file records all offsets off CMOS_BASE that is currently used by + * U-Boot for various reasons. It is put in such a unified place in order + * to be consistent across platforms. + */ + +/* stack address for S3 boot in a FSP configuration, 4 bytes */ +#define CMOS_FSP_STACK_ADDR CMOS_BASE + +#endif /* __CMOS_LAYOUT_H */ |