/*
 * fixmap.h: compile-time virtual memory allocation
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1998 Ingo Molnar
 *
 * Copyright 2008 Freescale Semiconductor Inc.
 *   Port to powerpc added by Kumar Gala
 */

#ifndef _ASM_FIXMAP_H
#define _ASM_FIXMAP_H

#ifndef __ASSEMBLER__
#include <linux/sizes.h>
#include <linux/pgtable.h>
#include <asm/page.h>
#ifdef CONFIG_HIGHMEM
#include <linux/threads.h>
#include <asm/kmap_size.h>
#endif

/*
 * 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. We allocate these special addresses
 * from the end of virtual memory (0xfffff000) backwards.
 * Also this lets us do fail-safe vmalloc(), we
 * can guarantee that these special addresses and
 * vmalloc()-ed addresses never overlap.
 *
 * these 'compile-time allocated' memory buffers are
 * fixed-size 4k pages. (or larger if used with an increment
 * highger than 1) use fixmap_set(idx,phys) to associate
 * physical memory with fixmap indices.
 *
 * TLB entries of such buffers will not be flushed across
 * task switches.
 */
enum fixed_addresses {
        FIX_HOLE,
#ifdef CONFIG_PPC32
        /* reserve the top 128K for early debugging purposes */
        FIX_EARLY_DEBUG_TOP = FIX_HOLE,
        FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+(ALIGN(SZ_128K, PAGE_SIZE)/PAGE_SIZE)-1,
#ifdef CONFIG_HIGHMEM
        FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
        FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
#endif
#ifdef CONFIG_PPC_8xx
        /* For IMMR we need an aligned 512K area */
#define FIX_IMMR_SIZE   (512 * 1024 / PAGE_SIZE)
        FIX_IMMR_START,
        FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
                       FIX_IMMR_SIZE,
#endif
#ifdef CONFIG_PPC_83xx
        /* For IMMR we need an aligned 2M area */
#define FIX_IMMR_SIZE   (SZ_2M / PAGE_SIZE)
        FIX_IMMR_START,
        FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
                       FIX_IMMR_SIZE,
#endif
        /* FIX_PCIE_MCFG, */
#endif /* CONFIG_PPC32 */
        __end_of_permanent_fixed_addresses,

#define NR_FIX_BTMAPS           (SZ_256K / PAGE_SIZE)
#define FIX_BTMAPS_SLOTS        16
#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 __FIXADDR_SIZE  (__end_of_fixed_addresses << PAGE_SHIFT)
#define FIXADDR_START           (FIXADDR_TOP - __FIXADDR_SIZE)

#define FIXMAP_ALIGNED_SIZE     (ALIGN(FIXADDR_TOP, PGDIR_SIZE) - \
                                 ALIGN_DOWN(FIXADDR_START, PGDIR_SIZE))
#define FIXMAP_PTE_SIZE (FIXMAP_ALIGNED_SIZE / PGDIR_SIZE * PTE_TABLE_SIZE)

#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG
#define FIXMAP_PAGE_IO  PAGE_KERNEL_NCG

#include <asm-generic/fixmap.h>

static inline void __set_fixmap(enum fixed_addresses idx,
                                phys_addr_t phys, pgprot_t flags)
{
        BUILD_BUG_ON(IS_ENABLED(CONFIG_PPC64) && __FIXADDR_SIZE > FIXADDR_SIZE);

        if (__builtin_constant_p(idx))
                BUILD_BUG_ON(idx >= __end_of_fixed_addresses);
        else if (WARN_ON(idx >= __end_of_fixed_addresses))
                return;
        if (pgprot_val(flags))
                map_kernel_page(__fix_to_virt(idx), phys, flags);
        else
                unmap_kernel_page(__fix_to_virt(idx));
}

#define __early_set_fixmap      __set_fixmap

#ifdef CONFIG_PPC_8xx
#define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE))
#endif

#endif /* !__ASSEMBLER__ */
#endif