xref: /linux/arch/m68k/include/asm/io_no.h (revision b7019ac550eb3916f34d79db583e9b7ea2524afa)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _M68KNOMMU_IO_H
3 #define _M68KNOMMU_IO_H
4 
5 /*
6  * Convert a physical memory address into a IO memory address.
7  * For us this is trivially a type cast.
8  */
9 #define iomem(a)	((void __iomem *) (a))
10 
11 /*
12  * The non-MMU m68k and ColdFire IO and memory mapped hardware access
13  * functions have always worked in CPU native endian. We need to define
14  * that behavior here first before we include asm-generic/io.h.
15  */
16 #define __raw_readb(addr) \
17     ({ unsigned char __v = (*(volatile unsigned char *) (addr)); __v; })
18 #define __raw_readw(addr) \
19     ({ unsigned short __v = (*(volatile unsigned short *) (addr)); __v; })
20 #define __raw_readl(addr) \
21     ({ unsigned int __v = (*(volatile unsigned int *) (addr)); __v; })
22 
23 #define __raw_writeb(b, addr) (void)((*(volatile unsigned char *) (addr)) = (b))
24 #define __raw_writew(b, addr) (void)((*(volatile unsigned short *) (addr)) = (b))
25 #define __raw_writel(b, addr) (void)((*(volatile unsigned int *) (addr)) = (b))
26 
27 #if defined(CONFIG_COLDFIRE)
28 /*
29  * For ColdFire platforms we may need to do some extra checks for what
30  * type of address range we are accessing. Include the ColdFire platform
31  * definitions so we can figure out if need to do something special.
32  */
33 #include <asm/byteorder.h>
34 #include <asm/coldfire.h>
35 #include <asm/mcfsim.h>
36 #endif /* CONFIG_COLDFIRE */
37 
38 #if defined(IOMEMBASE)
39 /*
40  * The ColdFire SoC internal peripherals are mapped into virtual address
41  * space using the ACR registers of the cache control unit. This means we
42  * are using a 1:1 physical:virtual mapping for them. We can quickly
43  * determine if we are accessing an internal peripheral device given the
44  * physical or vitrual address using the same range check. This check logic
45  * applies just the same of there is no MMU but something like a PCI bus
46  * is present.
47  */
48 static int __cf_internalio(unsigned long addr)
49 {
50 	return (addr >= IOMEMBASE) && (addr <= IOMEMBASE + IOMEMSIZE - 1);
51 }
52 
53 static int cf_internalio(const volatile void __iomem *addr)
54 {
55 	return __cf_internalio((unsigned long) addr);
56 }
57 
58 /*
59  * We need to treat built-in peripherals and bus based address ranges
60  * differently. Local built-in peripherals (and the ColdFire SoC parts
61  * have quite a lot of them) are always native endian - which is big
62  * endian on m68k/ColdFire. Bus based address ranges, like the PCI bus,
63  * are accessed little endian - so we need to byte swap those.
64  */
65 #define readw readw
66 static inline u16 readw(const volatile void __iomem *addr)
67 {
68 	if (cf_internalio(addr))
69 		return __raw_readw(addr);
70 	return __le16_to_cpu(__raw_readw(addr));
71 }
72 
73 #define readl readl
74 static inline u32 readl(const volatile void __iomem *addr)
75 {
76 	if (cf_internalio(addr))
77 		return __raw_readl(addr);
78 	return __le32_to_cpu(__raw_readl(addr));
79 }
80 
81 #define writew writew
82 static inline void writew(u16 value, volatile void __iomem *addr)
83 {
84 	if (cf_internalio(addr))
85 		__raw_writew(value, addr);
86 	else
87 		__raw_writew(__cpu_to_le16(value), addr);
88 }
89 
90 #define writel writel
91 static inline void writel(u32 value, volatile void __iomem *addr)
92 {
93 	if (cf_internalio(addr))
94 		__raw_writel(value, addr);
95 	else
96 		__raw_writel(__cpu_to_le32(value), addr);
97 }
98 
99 #else
100 
101 #define readb __raw_readb
102 #define readw __raw_readw
103 #define readl __raw_readl
104 #define writeb __raw_writeb
105 #define writew __raw_writew
106 #define writel __raw_writel
107 
108 #endif /* IOMEMBASE */
109 
110 #if defined(CONFIG_PCI)
111 /*
112  * Support for PCI bus access uses the asm-generic access functions.
113  * We need to supply the base address and masks for the normal memory
114  * and IO address space mappings.
115  */
116 #define PCI_MEM_PA	0xf0000000		/* Host physical address */
117 #define PCI_MEM_BA	0xf0000000		/* Bus physical address */
118 #define PCI_MEM_SIZE	0x08000000		/* 128 MB */
119 #define PCI_MEM_MASK	(PCI_MEM_SIZE - 1)
120 
121 #define PCI_IO_PA	0xf8000000		/* Host physical address */
122 #define PCI_IO_BA	0x00000000		/* Bus physical address */
123 #define PCI_IO_SIZE	0x00010000		/* 64k */
124 #define PCI_IO_MASK	(PCI_IO_SIZE - 1)
125 
126 #define HAVE_ARCH_PIO_SIZE
127 #define PIO_OFFSET	0
128 #define PIO_MASK	0xffff
129 #define PIO_RESERVED	0x10000
130 #define PCI_IOBASE	((void __iomem *) PCI_IO_PA)
131 #define PCI_SPACE_LIMIT	PCI_IO_MASK
132 #endif /* CONFIG_PCI */
133 
134 #include <asm/kmap.h>
135 #include <asm/virtconvert.h>
136 
137 #endif /* _M68KNOMMU_IO_H */
138