Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) /* SPDX-License-Identifier: GPL-2.0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) #ifndef __UM_FIXMAP_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) #define __UM_FIXMAP_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <asm/processor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <asm/kmap_types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <asm/archparam.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <asm/page.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/threads.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  * Here we define all the compile-time 'special' virtual
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  * addresses. The point is to have a constant address at
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  * compile time, but to set the physical address only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)  * in the boot process. We allocate these special  addresses
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)  * from the end of virtual memory (0xfffff000) backwards.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * Also this lets us do fail-safe vmalloc(), we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  * can guarantee that these special addresses and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)  * vmalloc()-ed addresses never overlap.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)  * these 'compile-time allocated' memory buffers are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)  * fixed-size 4k pages. (or larger if used with an increment
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)  * highger than 1) use fixmap_set(idx,phys) to associate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)  * physical memory with fixmap indices.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)  * TLB entries of such buffers will not be flushed across
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)  * task switches.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)  * on UP currently we will have no trace of the fixmap mechanizm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)  * no page table allocations, etc. This might change in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)  * future, say framebuffers for the console driver(s) could be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)  * fix-mapped?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) enum fixed_addresses {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	__end_of_fixed_addresses
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) extern void __set_fixmap (enum fixed_addresses idx,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 			  unsigned long phys, pgprot_t flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)  * used by vmalloc.c.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)  * Leave one empty page between vmalloc'ed areas and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)  * the start of the fixmap, and leave one page empty
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)  * at the top of mem..
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) #define FIXADDR_TOP	(TASK_SIZE - 2 * PAGE_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) #define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) #define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) #include <asm-generic/fixmap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) #endif