xref: /openbmc/linux/arch/s390/include/asm/pci_io.h (revision 4f3db074)
1 #ifndef _ASM_S390_PCI_IO_H
2 #define _ASM_S390_PCI_IO_H
3 
4 #ifdef CONFIG_PCI
5 
6 #include <linux/kernel.h>
7 #include <linux/slab.h>
8 #include <asm/pci_insn.h>
9 
10 /* I/O Map */
11 #define ZPCI_IOMAP_MAX_ENTRIES		0x7fff
12 #define ZPCI_IOMAP_ADDR_BASE		0x8000000000000000ULL
13 #define ZPCI_IOMAP_ADDR_IDX_MASK	0x7fff000000000000ULL
14 #define ZPCI_IOMAP_ADDR_OFF_MASK	0x0000ffffffffffffULL
15 
16 struct zpci_iomap_entry {
17 	u32 fh;
18 	u8 bar;
19 	u16 count;
20 };
21 
22 extern struct zpci_iomap_entry *zpci_iomap_start;
23 
24 #define ZPCI_IDX(addr)								\
25 	(((__force u64) addr & ZPCI_IOMAP_ADDR_IDX_MASK) >> 48)
26 #define ZPCI_OFFSET(addr)							\
27 	((__force u64) addr & ZPCI_IOMAP_ADDR_OFF_MASK)
28 
29 #define ZPCI_CREATE_REQ(handle, space, len)					\
30 	((u64) handle << 32 | space << 16 | len)
31 
32 #define zpci_read(LENGTH, RETTYPE)						\
33 static inline RETTYPE zpci_read_##RETTYPE(const volatile void __iomem *addr)	\
34 {										\
35 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
36 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
37 	u64 data;								\
38 	int rc;									\
39 										\
40 	rc = zpci_load(&data, req, ZPCI_OFFSET(addr));				\
41 	if (rc)									\
42 		data = -1ULL;							\
43 	return (RETTYPE) data;							\
44 }
45 
46 #define zpci_write(LENGTH, VALTYPE)						\
47 static inline void zpci_write_##VALTYPE(VALTYPE val,				\
48 					const volatile void __iomem *addr)	\
49 {										\
50 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
51 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
52 	u64 data = (VALTYPE) val;						\
53 										\
54 	zpci_store(data, req, ZPCI_OFFSET(addr));				\
55 }
56 
57 zpci_read(8, u64)
58 zpci_read(4, u32)
59 zpci_read(2, u16)
60 zpci_read(1, u8)
61 zpci_write(8, u64)
62 zpci_write(4, u32)
63 zpci_write(2, u16)
64 zpci_write(1, u8)
65 
66 static inline int zpci_write_single(u64 req, const u64 *data, u64 offset, u8 len)
67 {
68 	u64 val;
69 
70 	switch (len) {
71 	case 1:
72 		val = (u64) *((u8 *) data);
73 		break;
74 	case 2:
75 		val = (u64) *((u16 *) data);
76 		break;
77 	case 4:
78 		val = (u64) *((u32 *) data);
79 		break;
80 	case 8:
81 		val = (u64) *((u64 *) data);
82 		break;
83 	default:
84 		val = 0;		/* let FW report error */
85 		break;
86 	}
87 	return zpci_store(val, req, offset);
88 }
89 
90 static inline int zpci_read_single(u64 req, u64 *dst, u64 offset, u8 len)
91 {
92 	u64 data;
93 	int cc;
94 
95 	cc = zpci_load(&data, req, offset);
96 	if (cc)
97 		goto out;
98 
99 	switch (len) {
100 	case 1:
101 		*((u8 *) dst) = (u8) data;
102 		break;
103 	case 2:
104 		*((u16 *) dst) = (u16) data;
105 		break;
106 	case 4:
107 		*((u32 *) dst) = (u32) data;
108 		break;
109 	case 8:
110 		*((u64 *) dst) = (u64) data;
111 		break;
112 	}
113 out:
114 	return cc;
115 }
116 
117 static inline int zpci_write_block(u64 req, const u64 *data, u64 offset)
118 {
119 	return zpci_store_block(data, req, offset);
120 }
121 
122 static inline u8 zpci_get_max_write_size(u64 src, u64 dst, int len, int max)
123 {
124 	int count = len > max ? max : len, size = 1;
125 
126 	while (!(src & 0x1) && !(dst & 0x1) && ((size << 1) <= count)) {
127 		dst = dst >> 1;
128 		src = src >> 1;
129 		size = size << 1;
130 	}
131 	return size;
132 }
133 
134 static inline int zpci_memcpy_fromio(void *dst,
135 				     const volatile void __iomem *src,
136 				     unsigned long n)
137 {
138 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(src)];
139 	u64 req, offset = ZPCI_OFFSET(src);
140 	int size, rc = 0;
141 
142 	while (n > 0) {
143 		size = zpci_get_max_write_size((u64 __force) src,
144 					       (u64) dst, n, 8);
145 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
146 		rc = zpci_read_single(req, dst, offset, size);
147 		if (rc)
148 			break;
149 		offset += size;
150 		dst += size;
151 		n -= size;
152 	}
153 	return rc;
154 }
155 
156 static inline int zpci_memcpy_toio(volatile void __iomem *dst,
157 				   const void *src, unsigned long n)
158 {
159 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(dst)];
160 	u64 req, offset = ZPCI_OFFSET(dst);
161 	int size, rc = 0;
162 
163 	if (!src)
164 		return -EINVAL;
165 
166 	while (n > 0) {
167 		size = zpci_get_max_write_size((u64 __force) dst,
168 					       (u64) src, n, 128);
169 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
170 
171 		if (size > 8) /* main path */
172 			rc = zpci_write_block(req, src, offset);
173 		else
174 			rc = zpci_write_single(req, src, offset, size);
175 		if (rc)
176 			break;
177 		offset += size;
178 		src += size;
179 		n -= size;
180 	}
181 	return rc;
182 }
183 
184 static inline int zpci_memset_io(volatile void __iomem *dst,
185 				 unsigned char val, size_t count)
186 {
187 	u8 *src = kmalloc(count, GFP_KERNEL);
188 	int rc;
189 
190 	if (src == NULL)
191 		return -ENOMEM;
192 	memset(src, val, count);
193 
194 	rc = zpci_memcpy_toio(dst, src, count);
195 	kfree(src);
196 	return rc;
197 }
198 
199 #endif /* CONFIG_PCI */
200 
201 #endif /* _ASM_S390_PCI_IO_H */
202