linuxdebug/arch/parisc/include/asm/fixmap.h

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2024-07-16 15:50:57 +02:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_FIXMAP_H
#define _ASM_FIXMAP_H
/*
* This file defines the locations of the fixed mappings on parisc.
*
* All of the values in this file are machine virtual addresses.
*
* All of the values in this file must be <4GB (because of assembly
* loading restrictions). If you place this region anywhere above
* __PAGE_OFFSET, you must adjust the memory map accordingly
*/
/*
* The tmpalias region is used in kernel space to copy/clear/flush data
* from pages congruently mapped with user space. It is comprised of
* a pair regions. The size of these regions is determined by the largest
* cache aliasing boundary for machines that support equivalent aliasing.
*
* The c3750 with PA8700 processor returns an alias value of 11. This
* indicates that it has an alias boundary of 4 MB. It also supports
* non-equivalent aliasing without a performance penalty.
*
* Machines with PA8800/PA8900 processors return an alias value of 0.
* This indicates the alias boundary is unknown and may be larger than
* 16 MB. Non-equivalent aliasing is not supported.
*
* Here we assume the maximum alias boundary is 4 MB.
*/
#define TMPALIAS_SIZE_BITS 22 /* 4 MB */
#define TMPALIAS_MAP_START ((__PAGE_OFFSET) - (2 << TMPALIAS_SIZE_BITS))
#define FIXMAP_SIZE (FIX_BITMAP_COUNT << PAGE_SHIFT)
#define FIXMAP_START (TMPALIAS_MAP_START - FIXMAP_SIZE)
/* This is the kernel area for all maps (vmalloc, dma etc.) most
* usually, it extends up to TMPALIAS_MAP_START. Virtual addresses
* 0..GATEWAY_PAGE_SIZE are reserved for the gateway page */
#define KERNEL_MAP_START (GATEWAY_PAGE_SIZE)
#define KERNEL_MAP_END (FIXMAP_START)
#ifndef __ASSEMBLY__
enum fixed_addresses {
/* Support writing RO kernel text via kprobes, jump labels, etc. */
FIX_TEXT_POKE0,
FIX_TEXT_KEXEC,
FIX_BITMAP_COUNT
};
extern void *parisc_vmalloc_start;
#define PCXL_DMA_MAP_SIZE (8*1024*1024)
#define VMALLOC_START ((unsigned long)parisc_vmalloc_start)
#define VMALLOC_END (KERNEL_MAP_END)
#define __fix_to_virt(_x) (FIXMAP_START + ((_x) << PAGE_SHIFT))
void set_fixmap(enum fixed_addresses idx, phys_addr_t phys);
void clear_fixmap(enum fixed_addresses idx);
#endif /*__ASSEMBLY__*/
#endif /*_ASM_FIXMAP_H*/