xref: /openbmc/linux/arch/s390/include/asm/pci_io.h (revision 32981ea5)
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_SHIFT		48
12 #define ZPCI_IOMAP_ADDR_BASE		0x8000000000000000UL
13 #define ZPCI_IOMAP_ADDR_OFF_MASK	((1UL << ZPCI_IOMAP_SHIFT) - 1)
14 #define ZPCI_IOMAP_MAX_ENTRIES							\
15 	((ULONG_MAX - ZPCI_IOMAP_ADDR_BASE + 1) / (1UL << ZPCI_IOMAP_SHIFT))
16 #define ZPCI_IOMAP_ADDR_IDX_MASK						\
17 	(~ZPCI_IOMAP_ADDR_OFF_MASK - ZPCI_IOMAP_ADDR_BASE)
18 
19 struct zpci_iomap_entry {
20 	u32 fh;
21 	u8 bar;
22 	u16 count;
23 };
24 
25 extern struct zpci_iomap_entry *zpci_iomap_start;
26 
27 #define ZPCI_ADDR(idx) (ZPCI_IOMAP_ADDR_BASE | ((u64) idx << ZPCI_IOMAP_SHIFT))
28 #define ZPCI_IDX(addr)								\
29 	(((__force u64) addr & ZPCI_IOMAP_ADDR_IDX_MASK) >> ZPCI_IOMAP_SHIFT)
30 #define ZPCI_OFFSET(addr)							\
31 	((__force u64) addr & ZPCI_IOMAP_ADDR_OFF_MASK)
32 
33 #define ZPCI_CREATE_REQ(handle, space, len)					\
34 	((u64) handle << 32 | space << 16 | len)
35 
36 #define zpci_read(LENGTH, RETTYPE)						\
37 static inline RETTYPE zpci_read_##RETTYPE(const volatile void __iomem *addr)	\
38 {										\
39 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
40 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
41 	u64 data;								\
42 	int rc;									\
43 										\
44 	rc = zpci_load(&data, req, ZPCI_OFFSET(addr));				\
45 	if (rc)									\
46 		data = -1ULL;							\
47 	return (RETTYPE) data;							\
48 }
49 
50 #define zpci_write(LENGTH, VALTYPE)						\
51 static inline void zpci_write_##VALTYPE(VALTYPE val,				\
52 					const volatile void __iomem *addr)	\
53 {										\
54 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
55 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
56 	u64 data = (VALTYPE) val;						\
57 										\
58 	zpci_store(data, req, ZPCI_OFFSET(addr));				\
59 }
60 
61 zpci_read(8, u64)
62 zpci_read(4, u32)
63 zpci_read(2, u16)
64 zpci_read(1, u8)
65 zpci_write(8, u64)
66 zpci_write(4, u32)
67 zpci_write(2, u16)
68 zpci_write(1, u8)
69 
70 static inline int zpci_write_single(u64 req, const u64 *data, u64 offset, u8 len)
71 {
72 	u64 val;
73 
74 	switch (len) {
75 	case 1:
76 		val = (u64) *((u8 *) data);
77 		break;
78 	case 2:
79 		val = (u64) *((u16 *) data);
80 		break;
81 	case 4:
82 		val = (u64) *((u32 *) data);
83 		break;
84 	case 8:
85 		val = (u64) *((u64 *) data);
86 		break;
87 	default:
88 		val = 0;		/* let FW report error */
89 		break;
90 	}
91 	return zpci_store(val, req, offset);
92 }
93 
94 static inline int zpci_read_single(u64 req, u64 *dst, u64 offset, u8 len)
95 {
96 	u64 data;
97 	int cc;
98 
99 	cc = zpci_load(&data, req, offset);
100 	if (cc)
101 		goto out;
102 
103 	switch (len) {
104 	case 1:
105 		*((u8 *) dst) = (u8) data;
106 		break;
107 	case 2:
108 		*((u16 *) dst) = (u16) data;
109 		break;
110 	case 4:
111 		*((u32 *) dst) = (u32) data;
112 		break;
113 	case 8:
114 		*((u64 *) dst) = (u64) data;
115 		break;
116 	}
117 out:
118 	return cc;
119 }
120 
121 static inline int zpci_write_block(u64 req, const u64 *data, u64 offset)
122 {
123 	return zpci_store_block(data, req, offset);
124 }
125 
126 static inline u8 zpci_get_max_write_size(u64 src, u64 dst, int len, int max)
127 {
128 	int count = len > max ? max : len, size = 1;
129 
130 	while (!(src & 0x1) && !(dst & 0x1) && ((size << 1) <= count)) {
131 		dst = dst >> 1;
132 		src = src >> 1;
133 		size = size << 1;
134 	}
135 	return size;
136 }
137 
138 static inline int zpci_memcpy_fromio(void *dst,
139 				     const volatile void __iomem *src,
140 				     unsigned long n)
141 {
142 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(src)];
143 	u64 req, offset = ZPCI_OFFSET(src);
144 	int size, rc = 0;
145 
146 	while (n > 0) {
147 		size = zpci_get_max_write_size((u64 __force) src,
148 					       (u64) dst, n, 8);
149 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
150 		rc = zpci_read_single(req, dst, offset, size);
151 		if (rc)
152 			break;
153 		offset += size;
154 		dst += size;
155 		n -= size;
156 	}
157 	return rc;
158 }
159 
160 static inline int zpci_memcpy_toio(volatile void __iomem *dst,
161 				   const void *src, unsigned long n)
162 {
163 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(dst)];
164 	u64 req, offset = ZPCI_OFFSET(dst);
165 	int size, rc = 0;
166 
167 	if (!src)
168 		return -EINVAL;
169 
170 	while (n > 0) {
171 		size = zpci_get_max_write_size((u64 __force) dst,
172 					       (u64) src, n, 128);
173 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
174 
175 		if (size > 8) /* main path */
176 			rc = zpci_write_block(req, src, offset);
177 		else
178 			rc = zpci_write_single(req, src, offset, size);
179 		if (rc)
180 			break;
181 		offset += size;
182 		src += size;
183 		n -= size;
184 	}
185 	return rc;
186 }
187 
188 static inline int zpci_memset_io(volatile void __iomem *dst,
189 				 unsigned char val, size_t count)
190 {
191 	u8 *src = kmalloc(count, GFP_KERNEL);
192 	int rc;
193 
194 	if (src == NULL)
195 		return -ENOMEM;
196 	memset(src, val, count);
197 
198 	rc = zpci_memcpy_toio(dst, src, count);
199 	kfree(src);
200 	return rc;
201 }
202 
203 #endif /* CONFIG_PCI */
204 
205 #endif /* _ASM_S390_PCI_IO_H */
206