Atish Patra 6262f661ff
RISC-V: Add early ioremap support
UEFI uses early IO or memory mappings for runtime services before
normal ioremap() is usable. Add the necessary fixmap bindings and
pmd mappings for generic ioremap support to work.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-10-02 14:31:03 -07:00

60 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
*/
#ifndef _ASM_RISCV_FIXMAP_H
#define _ASM_RISCV_FIXMAP_H
#include <linux/kernel.h>
#include <linux/sizes.h>
#include <linux/pgtable.h>
#include <asm/page.h>
#ifdef CONFIG_MMU
/*
* Here we define all the compile-time 'special' virtual addresses.
* The point is to have a constant address at compile time, but to
* set the physical address only in the boot process.
*
* These 'compile-time allocated' memory buffers are page-sized. Use
* set_fixmap(idx,phys) to associate physical memory with fixmap indices.
*/
enum fixed_addresses {
FIX_HOLE,
FIX_PTE,
FIX_PMD,
FIX_TEXT_POKE1,
FIX_TEXT_POKE0,
FIX_EARLYCON_MEM_BASE,
__end_of_permanent_fixed_addresses,
/*
* Temporary boot-time mappings, used by early_ioremap(),
* before ioremap() is functional.
*/
#define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE)
#define FIX_BTMAPS_SLOTS 7
#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
__end_of_fixed_addresses
};
#define FIXMAP_PAGE_IO PAGE_KERNEL
#define __early_set_fixmap __set_fixmap
#define __late_set_fixmap __set_fixmap
#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
extern void __set_fixmap(enum fixed_addresses idx,
phys_addr_t phys, pgprot_t prot);
#include <asm-generic/fixmap.h>
#endif /* CONFIG_MMU */
#endif /* _ASM_RISCV_FIXMAP_H */