1 | // SPDX-License-Identifier: GPL-2.0 |
---|---|
2 | #include <linux/init.h> |
3 | #include <linux/module.h> |
4 | #include <linux/sizes.h> |
5 | #include <asm/page.h> |
6 | #include <asm/addrspace.h> |
7 | |
8 | /* |
9 | * This is the offset of the uncached section from its cached alias. |
10 | * |
11 | * Legacy platforms handle trivial transitions between cached and |
12 | * uncached segments by making use of the 1:1 mapping relationship in |
13 | * 512MB lowmem, others via a special uncached mapping. |
14 | * |
15 | * Default value only valid in 29 bit mode, in 32bit mode this will be |
16 | * updated by the early PMB initialization code. |
17 | */ |
18 | unsigned long cached_to_uncached = SZ_512M; |
19 | unsigned long uncached_size = SZ_512M; |
20 | unsigned long uncached_start, uncached_end; |
21 | EXPORT_SYMBOL(uncached_start); |
22 | EXPORT_SYMBOL(uncached_end); |
23 | |
24 | int virt_addr_uncached(unsigned long kaddr) |
25 | { |
26 | return (kaddr >= uncached_start) && (kaddr < uncached_end); |
27 | } |
28 | EXPORT_SYMBOL(virt_addr_uncached); |
29 | |
30 | void __init uncached_init(void) |
31 | { |
32 | #if defined(CONFIG_29BIT) || !defined(CONFIG_MMU) |
33 | uncached_start = P2SEG; |
34 | #else |
35 | uncached_start = memory_end; |
36 | #endif |
37 | uncached_end = uncached_start + uncached_size; |
38 | } |
39 | |
40 | void __init uncached_resize(unsigned long size) |
41 | { |
42 | uncached_size = size; |
43 | uncached_end = uncached_start + uncached_size; |
44 | } |
45 |