xref: /openbmc/linux/arch/loongarch/include/asm/io.h (revision bbaf1ff0)
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 #define ARCH_HAS_IOREMAP_WC
9 
10 #include <linux/kernel.h>
11 #include <linux/types.h>
12 
13 #include <asm/addrspace.h>
14 #include <asm/cpu.h>
15 #include <asm/page.h>
16 #include <asm/pgtable-bits.h>
17 #include <asm/string.h>
18 
19 /*
20  * Change "struct page" to physical address.
21  */
22 #define page_to_phys(page)	((phys_addr_t)page_to_pfn(page) << PAGE_SHIFT)
23 
24 extern void __init __iomem *early_ioremap(u64 phys_addr, unsigned long size);
25 extern void __init early_iounmap(void __iomem *addr, unsigned long size);
26 
27 #define early_memremap early_ioremap
28 #define early_memunmap early_iounmap
29 
30 #ifdef CONFIG_ARCH_IOREMAP
31 
32 static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
33 					 unsigned long prot_val)
34 {
35 	if (prot_val & _CACHE_CC)
36 		return (void __iomem *)(unsigned long)(CACHE_BASE + offset);
37 	else
38 		return (void __iomem *)(unsigned long)(UNCACHE_BASE + offset);
39 }
40 
41 #define ioremap(offset, size)		\
42 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL_SUC))
43 
44 #define iounmap(addr) 			((void)(addr))
45 
46 #endif
47 
48 /*
49  * On LoongArch, ioremap() has two variants, ioremap_wc() and ioremap_cache().
50  * They map bus memory into CPU space, the mapped memory is marked uncachable
51  * (_CACHE_SUC), uncachable but accelerated by write-combine (_CACHE_WUC) and
52  * cachable (_CACHE_CC) respectively for CPU access.
53  *
54  * @offset:    bus address of the memory
55  * @size:      size of the resource to map
56  */
57 extern pgprot_t pgprot_wc;
58 
59 #define ioremap_wc(offset, size)	\
60 	ioremap_prot((offset), (size), pgprot_val(pgprot_wc))
61 
62 #define ioremap_cache(offset, size)	\
63 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL))
64 
65 #define mmiowb() asm volatile ("dbar 0" ::: "memory")
66 
67 /*
68  * String version of I/O memory access operations.
69  */
70 extern void __memset_io(volatile void __iomem *dst, int c, size_t count);
71 extern void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count);
72 extern void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count);
73 #define memset_io(c, v, l)     __memset_io((c), (v), (l))
74 #define memcpy_fromio(a, c, l) __memcpy_fromio((a), (c), (l))
75 #define memcpy_toio(c, a, l)   __memcpy_toio((c), (a), (l))
76 
77 #include <asm-generic/io.h>
78 
79 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
80 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
81 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
82 
83 #endif /* _ASM_IO_H */
84