xref: /openbmc/linux/arch/loongarch/include/asm/io.h (revision ac191bcb)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #ifndef _ASM_IO_H
6 #define _ASM_IO_H
7 
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 
11 #include <asm/addrspace.h>
12 #include <asm/cpu.h>
13 #include <asm/page.h>
14 #include <asm/pgtable-bits.h>
15 #include <asm/string.h>
16 
17 /*
18  * Change "struct page" to physical address.
19  */
20 #define page_to_phys(page)	((phys_addr_t)page_to_pfn(page) << PAGE_SHIFT)
21 
22 extern void __init __iomem *early_ioremap(u64 phys_addr, unsigned long size);
23 extern void __init early_iounmap(void __iomem *addr, unsigned long size);
24 
25 #define early_memremap early_ioremap
26 #define early_memunmap early_iounmap
27 
28 #ifdef CONFIG_ARCH_IOREMAP
29 
30 static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
31 					 unsigned long prot_val)
32 {
33 	if (prot_val & _CACHE_CC)
34 		return (void __iomem *)(unsigned long)(CACHE_BASE + offset);
35 	else
36 		return (void __iomem *)(unsigned long)(UNCACHE_BASE + offset);
37 }
38 
39 #define ioremap(offset, size)		\
40 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL_SUC))
41 
42 #define iounmap(addr) 			((void)(addr))
43 
44 #endif
45 
46 /*
47  * On LoongArch, ioremap() has two variants, ioremap_wc() and ioremap_cache().
48  * They map bus memory into CPU space, the mapped memory is marked uncachable
49  * (_CACHE_SUC), uncachable but accelerated by write-combine (_CACHE_WUC) and
50  * cachable (_CACHE_CC) respectively for CPU access.
51  *
52  * @offset:    bus address of the memory
53  * @size:      size of the resource to map
54  */
55 #define ioremap_wc(offset, size)	\
56 	ioremap_prot((offset), (size),	\
57 		pgprot_val(wc_enabled ? PAGE_KERNEL_WUC : PAGE_KERNEL_SUC))
58 
59 #define ioremap_cache(offset, size)	\
60 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL))
61 
62 #define mmiowb() wmb()
63 
64 /*
65  * String version of I/O memory access operations.
66  */
67 extern void __memset_io(volatile void __iomem *dst, int c, size_t count);
68 extern void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count);
69 extern void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count);
70 #define memset_io(c, v, l)     __memset_io((c), (v), (l))
71 #define memcpy_fromio(a, c, l) __memcpy_fromio((a), (c), (l))
72 #define memcpy_toio(c, a, l)   __memcpy_toio((c), (a), (l))
73 
74 #define __io_aw() mmiowb()
75 
76 #include <asm-generic/io.h>
77 
78 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
79 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
80 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
81 
82 #endif /* _ASM_IO_H */
83