forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
56 lines
1.6 KiB
56 lines
1.6 KiB
/* SPDX-License-Identifier: GPL-2.0 */ |
|
#ifndef __UM_FIXMAP_H |
|
#define __UM_FIXMAP_H |
|
|
|
#include <asm/processor.h> |
|
#include <asm/archparam.h> |
|
#include <asm/page.h> |
|
#include <linux/threads.h> |
|
|
|
/* |
|
* 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. |
|
*/ |
|
|
|
/* |
|
* on UP currently we will have no trace of the fixmap mechanizm, |
|
* no page table allocations, etc. This might change in the |
|
* future, say framebuffers for the console driver(s) could be |
|
* fix-mapped? |
|
*/ |
|
enum fixed_addresses { |
|
__end_of_fixed_addresses |
|
}; |
|
|
|
extern void __set_fixmap (enum fixed_addresses idx, |
|
unsigned long phys, pgprot_t flags); |
|
|
|
/* |
|
* used by vmalloc.c. |
|
* |
|
* Leave one empty page between vmalloc'ed areas and |
|
* the start of the fixmap, and leave one page empty |
|
* at the top of mem.. |
|
*/ |
|
|
|
#define FIXADDR_TOP (TASK_SIZE - 2 * PAGE_SIZE) |
|
#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) |
|
#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) |
|
|
|
#include <asm-generic/fixmap.h> |
|
|
|
#endif
|
|
|