xref: /openbmc/linux/arch/s390/include/asm/pci_io.h (revision e3d786a3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_S390_PCI_IO_H
3 #define _ASM_S390_PCI_IO_H
4 
5 #ifdef CONFIG_PCI
6 
7 #include <linux/kernel.h>
8 #include <linux/slab.h>
9 #include <asm/pci_insn.h>
10 
11 /* I/O Map */
12 #define ZPCI_IOMAP_SHIFT		48
13 #define ZPCI_IOMAP_ADDR_BASE		0x8000000000000000UL
14 #define ZPCI_IOMAP_ADDR_OFF_MASK	((1UL << ZPCI_IOMAP_SHIFT) - 1)
15 #define ZPCI_IOMAP_MAX_ENTRIES							\
16 	((ULONG_MAX - ZPCI_IOMAP_ADDR_BASE + 1) / (1UL << ZPCI_IOMAP_SHIFT))
17 #define ZPCI_IOMAP_ADDR_IDX_MASK						\
18 	(~ZPCI_IOMAP_ADDR_OFF_MASK - ZPCI_IOMAP_ADDR_BASE)
19 
20 struct zpci_iomap_entry {
21 	u32 fh;
22 	u8 bar;
23 	u16 count;
24 };
25 
26 extern struct zpci_iomap_entry *zpci_iomap_start;
27 
28 #define ZPCI_ADDR(idx) (ZPCI_IOMAP_ADDR_BASE | ((u64) idx << ZPCI_IOMAP_SHIFT))
29 #define ZPCI_IDX(addr)								\
30 	(((__force u64) addr & ZPCI_IOMAP_ADDR_IDX_MASK) >> ZPCI_IOMAP_SHIFT)
31 #define ZPCI_OFFSET(addr)							\
32 	((__force u64) addr & ZPCI_IOMAP_ADDR_OFF_MASK)
33 
34 #define ZPCI_CREATE_REQ(handle, space, len)					\
35 	((u64) handle << 32 | space << 16 | len)
36 
37 #define zpci_read(LENGTH, RETTYPE)						\
38 static inline RETTYPE zpci_read_##RETTYPE(const volatile void __iomem *addr)	\
39 {										\
40 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
41 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
42 	u64 data;								\
43 	int rc;									\
44 										\
45 	rc = zpci_load(&data, req, ZPCI_OFFSET(addr));				\
46 	if (rc)									\
47 		data = -1ULL;							\
48 	return (RETTYPE) data;							\
49 }
50 
51 #define zpci_write(LENGTH, VALTYPE)						\
52 static inline void zpci_write_##VALTYPE(VALTYPE val,				\
53 					const volatile void __iomem *addr)	\
54 {										\
55 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(addr)];	\
56 	u64 req = ZPCI_CREATE_REQ(entry->fh, entry->bar, LENGTH);		\
57 	u64 data = (VALTYPE) val;						\
58 										\
59 	zpci_store(data, req, ZPCI_OFFSET(addr));				\
60 }
61 
62 zpci_read(8, u64)
63 zpci_read(4, u32)
64 zpci_read(2, u16)
65 zpci_read(1, u8)
66 zpci_write(8, u64)
67 zpci_write(4, u32)
68 zpci_write(2, u16)
69 zpci_write(1, u8)
70 
71 static inline int zpci_write_single(u64 req, const u64 *data, u64 offset, u8 len)
72 {
73 	u64 val;
74 
75 	switch (len) {
76 	case 1:
77 		val = (u64) *((u8 *) data);
78 		break;
79 	case 2:
80 		val = (u64) *((u16 *) data);
81 		break;
82 	case 4:
83 		val = (u64) *((u32 *) data);
84 		break;
85 	case 8:
86 		val = (u64) *((u64 *) data);
87 		break;
88 	default:
89 		val = 0;		/* let FW report error */
90 		break;
91 	}
92 	return zpci_store(val, req, offset);
93 }
94 
95 static inline int zpci_read_single(u64 req, u64 *dst, u64 offset, u8 len)
96 {
97 	u64 data;
98 	int cc;
99 
100 	cc = zpci_load(&data, req, offset);
101 	if (cc)
102 		goto out;
103 
104 	switch (len) {
105 	case 1:
106 		*((u8 *) dst) = (u8) data;
107 		break;
108 	case 2:
109 		*((u16 *) dst) = (u16) data;
110 		break;
111 	case 4:
112 		*((u32 *) dst) = (u32) data;
113 		break;
114 	case 8:
115 		*((u64 *) dst) = (u64) data;
116 		break;
117 	}
118 out:
119 	return cc;
120 }
121 
122 static inline int zpci_write_block(u64 req, const u64 *data, u64 offset)
123 {
124 	return zpci_store_block(data, req, offset);
125 }
126 
127 static inline u8 zpci_get_max_write_size(u64 src, u64 dst, int len, int max)
128 {
129 	int count = len > max ? max : len, size = 1;
130 
131 	while (!(src & 0x1) && !(dst & 0x1) && ((size << 1) <= count)) {
132 		dst = dst >> 1;
133 		src = src >> 1;
134 		size = size << 1;
135 	}
136 	return size;
137 }
138 
139 static inline int zpci_memcpy_fromio(void *dst,
140 				     const volatile void __iomem *src,
141 				     unsigned long n)
142 {
143 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(src)];
144 	u64 req, offset = ZPCI_OFFSET(src);
145 	int size, rc = 0;
146 
147 	while (n > 0) {
148 		size = zpci_get_max_write_size((u64 __force) src,
149 					       (u64) dst, n, 8);
150 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
151 		rc = zpci_read_single(req, dst, offset, size);
152 		if (rc)
153 			break;
154 		offset += size;
155 		dst += size;
156 		n -= size;
157 	}
158 	return rc;
159 }
160 
161 static inline int zpci_memcpy_toio(volatile void __iomem *dst,
162 				   const void *src, unsigned long n)
163 {
164 	struct zpci_iomap_entry *entry = &zpci_iomap_start[ZPCI_IDX(dst)];
165 	u64 req, offset = ZPCI_OFFSET(dst);
166 	int size, rc = 0;
167 
168 	if (!src)
169 		return -EINVAL;
170 
171 	while (n > 0) {
172 		size = zpci_get_max_write_size((u64 __force) dst,
173 					       (u64) src, n, 128);
174 		req = ZPCI_CREATE_REQ(entry->fh, entry->bar, size);
175 
176 		if (size > 8) /* main path */
177 			rc = zpci_write_block(req, src, offset);
178 		else
179 			rc = zpci_write_single(req, src, offset, size);
180 		if (rc)
181 			break;
182 		offset += size;
183 		src += size;
184 		n -= size;
185 	}
186 	return rc;
187 }
188 
189 static inline int zpci_memset_io(volatile void __iomem *dst,
190 				 unsigned char val, size_t count)
191 {
192 	u8 *src = kmalloc(count, GFP_KERNEL);
193 	int rc;
194 
195 	if (src == NULL)
196 		return -ENOMEM;
197 	memset(src, val, count);
198 
199 	rc = zpci_memcpy_toio(dst, src, count);
200 	kfree(src);
201 	return rc;
202 }
203 
204 #endif /* CONFIG_PCI */
205 
206 #endif /* _ASM_S390_PCI_IO_H */
207