1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright(c) 2010 Intel Corporation. All rights reserved.
4 *
5 * Contact Information:
6 * Intel Corporation
7 * 2200 Mission College Blvd.
8 * Santa Clara, CA 97052
9 *
10 * This provides access methods for PCI registers that mis-behave on
11 * the CE4100. Each register can be assigned a private init, read and
12 * write routine. The exception to this is the bridge device. The
13 * bridge device is the only device on bus zero (0) that requires any
14 * fixup so it is a special case ATM
15 */
16
17#include <linux/kernel.h>
18#include <linux/pci.h>
19#include <linux/init.h>
20
21#include <asm/ce4100.h>
22#include <asm/pci_x86.h>
23
24struct sim_reg {
25 u32 value;
26 u32 mask;
27};
28
29struct sim_dev_reg {
30 int dev_func;
31 int reg;
32 void (*init)(struct sim_dev_reg *reg);
33 void (*read)(struct sim_dev_reg *reg, u32 *value);
34 void (*write)(struct sim_dev_reg *reg, u32 value);
35 struct sim_reg sim_reg;
36};
37
38struct sim_reg_op {
39 void (*init)(struct sim_dev_reg *reg);
40 void (*read)(struct sim_dev_reg *reg, u32 value);
41 void (*write)(struct sim_dev_reg *reg, u32 value);
42};
43
44#define MB (1024 * 1024)
45#define KB (1024)
46#define SIZE_TO_MASK(size) (~(size - 1))
47
48#define DEFINE_REG(device, func, offset, size, init_op, read_op, write_op)\
49{ PCI_DEVFN(device, func), offset, init_op, read_op, write_op,\
50 {0, SIZE_TO_MASK(size)} },
51
52/*
53 * All read/write functions are called with pci_config_lock held.
54 */
55static void reg_init(struct sim_dev_reg *reg)
56{
57 pci_direct_conf1.read(0, 1, reg->dev_func, reg->reg, 4,
58 &reg->sim_reg.value);
59}
60
61static void reg_read(struct sim_dev_reg *reg, u32 *value)
62{
63 *value = reg->sim_reg.value;
64}
65
66static void reg_write(struct sim_dev_reg *reg, u32 value)
67{
68 reg->sim_reg.value = (value & reg->sim_reg.mask) |
69 (reg->sim_reg.value & ~reg->sim_reg.mask);
70}
71
72static void sata_reg_init(struct sim_dev_reg *reg)
73{
74 pci_direct_conf1.read(0, 1, PCI_DEVFN(14, 0), 0x10, 4,
75 &reg->sim_reg.value);
76 reg->sim_reg.value += 0x400;
77}
78
79static void ehci_reg_read(struct sim_dev_reg *reg, u32 *value)
80{
81 reg_read(reg, value);
82 if (*value != reg->sim_reg.mask)
83 *value |= 0x100;
84}
85
86static void sata_revid_init(struct sim_dev_reg *reg)
87{
88 reg->sim_reg.value = 0x01060100;
89 reg->sim_reg.mask = 0;
90}
91
92static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
93{
94 reg_read(reg, value);
95}
96
97static void reg_noirq_read(struct sim_dev_reg *reg, u32 *value)
98{
99 /* force interrupt pin value to 0 */
100 *value = reg->sim_reg.value & 0xfff00ff;
101}
102
103static struct sim_dev_reg bus1_fixups[] = {
104 DEFINE_REG(2, 0, 0x10, (16*MB), reg_init, reg_read, reg_write)
105 DEFINE_REG(2, 0, 0x14, (256), reg_init, reg_read, reg_write)
106 DEFINE_REG(2, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
107 DEFINE_REG(3, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
108 DEFINE_REG(4, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
109 DEFINE_REG(4, 1, 0x10, (128*KB), reg_init, reg_read, reg_write)
110 DEFINE_REG(6, 0, 0x10, (512*KB), reg_init, reg_read, reg_write)
111 DEFINE_REG(6, 1, 0x10, (512*KB), reg_init, reg_read, reg_write)
112 DEFINE_REG(6, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
113 DEFINE_REG(8, 0, 0x10, (1*MB), reg_init, reg_read, reg_write)
114 DEFINE_REG(8, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
115 DEFINE_REG(8, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
116 DEFINE_REG(9, 0, 0x10 , (1*MB), reg_init, reg_read, reg_write)
117 DEFINE_REG(9, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
118 DEFINE_REG(10, 0, 0x10, (256), reg_init, reg_read, reg_write)
119 DEFINE_REG(10, 0, 0x14, (256*MB), reg_init, reg_read, reg_write)
120 DEFINE_REG(11, 0, 0x10, (256), reg_init, reg_read, reg_write)
121 DEFINE_REG(11, 0, 0x14, (256), reg_init, reg_read, reg_write)
122 DEFINE_REG(11, 1, 0x10, (256), reg_init, reg_read, reg_write)
123 DEFINE_REG(11, 2, 0x10, (256), reg_init, reg_read, reg_write)
124 DEFINE_REG(11, 2, 0x14, (256), reg_init, reg_read, reg_write)
125 DEFINE_REG(11, 2, 0x18, (256), reg_init, reg_read, reg_write)
126 DEFINE_REG(11, 3, 0x10, (256), reg_init, reg_read, reg_write)
127 DEFINE_REG(11, 3, 0x14, (256), reg_init, reg_read, reg_write)
128 DEFINE_REG(11, 4, 0x10, (256), reg_init, reg_read, reg_write)
129 DEFINE_REG(11, 5, 0x10, (64*KB), reg_init, reg_read, reg_write)
130 DEFINE_REG(11, 6, 0x10, (256), reg_init, reg_read, reg_write)
131 DEFINE_REG(11, 7, 0x10, (64*KB), reg_init, reg_read, reg_write)
132 DEFINE_REG(11, 7, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
133 DEFINE_REG(12, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
134 DEFINE_REG(12, 0, 0x14, (256), reg_init, reg_read, reg_write)
135 DEFINE_REG(12, 1, 0x10, (1024), reg_init, reg_read, reg_write)
136 DEFINE_REG(13, 0, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
137 DEFINE_REG(13, 1, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
138 DEFINE_REG(14, 0, 0x8, 0, sata_revid_init, sata_revid_read, 0)
139 DEFINE_REG(14, 0, 0x10, 0, reg_init, reg_read, reg_write)
140 DEFINE_REG(14, 0, 0x14, 0, reg_init, reg_read, reg_write)
141 DEFINE_REG(14, 0, 0x18, 0, reg_init, reg_read, reg_write)
142 DEFINE_REG(14, 0, 0x1C, 0, reg_init, reg_read, reg_write)
143 DEFINE_REG(14, 0, 0x20, 0, reg_init, reg_read, reg_write)
144 DEFINE_REG(14, 0, 0x24, (0x200), sata_reg_init, reg_read, reg_write)
145 DEFINE_REG(15, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
146 DEFINE_REG(15, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
147 DEFINE_REG(16, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
148 DEFINE_REG(16, 0, 0x14, (64*MB), reg_init, reg_read, reg_write)
149 DEFINE_REG(16, 0, 0x18, (64*MB), reg_init, reg_read, reg_write)
150 DEFINE_REG(16, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
151 DEFINE_REG(17, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
152 DEFINE_REG(18, 0, 0x10, (1*KB), reg_init, reg_read, reg_write)
153 DEFINE_REG(18, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
154};
155
156static void __init init_sim_regs(void)
157{
158 int i;
159
160 for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
161 if (bus1_fixups[i].init)
162 bus1_fixups[i].init(&bus1_fixups[i]);
163 }
164}
165
166static inline void extract_bytes(u32 *value, int reg, int len)
167{
168 uint32_t mask;
169
170 *value >>= ((reg & 3) * 8);
171 mask = 0xFFFFFFFF >> ((4 - len) * 8);
172 *value &= mask;
173}
174
175static int bridge_read(unsigned int devfn, int reg, int len, u32 *value)
176{
177 u32 av_bridge_base, av_bridge_limit;
178 int retval = 0;
179
180 switch (reg) {
181 /* Make BARs appear to not request any memory. */
182 case PCI_BASE_ADDRESS_0:
183 case PCI_BASE_ADDRESS_0 + 1:
184 case PCI_BASE_ADDRESS_0 + 2:
185 case PCI_BASE_ADDRESS_0 + 3:
186 *value = 0;
187 break;
188
189 /* Since subordinate bus number register is hardwired
190 * to zero and read only, so do the simulation.
191 */
192 case PCI_PRIMARY_BUS:
193 if (len == 4)
194 *value = 0x00010100;
195 break;
196
197 case PCI_SUBORDINATE_BUS:
198 *value = 1;
199 break;
200
201 case PCI_MEMORY_BASE:
202 case PCI_MEMORY_LIMIT:
203 /* Get the A/V bridge base address. */
204 pci_direct_conf1.read(0, 0, devfn,
205 PCI_BASE_ADDRESS_0, 4, &av_bridge_base);
206
207 av_bridge_limit = av_bridge_base + (512*MB - 1);
208 av_bridge_limit >>= 16;
209 av_bridge_limit &= 0xFFF0;
210
211 av_bridge_base >>= 16;
212 av_bridge_base &= 0xFFF0;
213
214 if (reg == PCI_MEMORY_LIMIT)
215 *value = av_bridge_limit;
216 else if (len == 2)
217 *value = av_bridge_base;
218 else
219 *value = (av_bridge_limit << 16) | av_bridge_base;
220 break;
221 /* Make prefetchable memory limit smaller than prefetchable
222 * memory base, so not claim prefetchable memory space.
223 */
224 case PCI_PREF_MEMORY_BASE:
225 *value = 0xFFF0;
226 break;
227 case PCI_PREF_MEMORY_LIMIT:
228 *value = 0x0;
229 break;
230 /* Make IO limit smaller than IO base, so not claim IO space. */
231 case PCI_IO_BASE:
232 *value = 0xF0;
233 break;
234 case PCI_IO_LIMIT:
235 *value = 0;
236 break;
237 default:
238 retval = 1;
239 }
240 return retval;
241}
242
243static int ce4100_bus1_read(unsigned int devfn, int reg, int len, u32 *value)
244{
245 unsigned long flags;
246 int i;
247
248 for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
249 if (bus1_fixups[i].dev_func == devfn &&
250 bus1_fixups[i].reg == (reg & ~3) &&
251 bus1_fixups[i].read) {
252
253 raw_spin_lock_irqsave(&pci_config_lock, flags);
254 bus1_fixups[i].read(&(bus1_fixups[i]), value);
255 raw_spin_unlock_irqrestore(&pci_config_lock, flags);
256 extract_bytes(value, reg, len);
257 return 0;
258 }
259 }
260 return -1;
261}
262
263static int ce4100_conf_read(unsigned int seg, unsigned int bus,
264 unsigned int devfn, int reg, int len, u32 *value)
265{
266 WARN_ON(seg);
267
268 if (bus == 1 && !ce4100_bus1_read(devfn, reg, len, value))
269 return 0;
270
271 if (bus == 0 && (PCI_DEVFN(1, 0) == devfn) &&
272 !bridge_read(devfn, reg, len, value))
273 return 0;
274
275 return pci_direct_conf1.read(seg, bus, devfn, reg, len, value);
276}
277
278static int ce4100_bus1_write(unsigned int devfn, int reg, int len, u32 value)
279{
280 unsigned long flags;
281 int i;
282
283 for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
284 if (bus1_fixups[i].dev_func == devfn &&
285 bus1_fixups[i].reg == (reg & ~3) &&
286 bus1_fixups[i].write) {
287
288 raw_spin_lock_irqsave(&pci_config_lock, flags);
289 bus1_fixups[i].write(&(bus1_fixups[i]), value);
290 raw_spin_unlock_irqrestore(&pci_config_lock, flags);
291 return 0;
292 }
293 }
294 return -1;
295}
296
297static int ce4100_conf_write(unsigned int seg, unsigned int bus,
298 unsigned int devfn, int reg, int len, u32 value)
299{
300 WARN_ON(seg);
301
302 if (bus == 1 && !ce4100_bus1_write(devfn, reg, len, value))
303 return 0;
304
305 /* Discard writes to A/V bridge BAR. */
306 if (bus == 0 && PCI_DEVFN(1, 0) == devfn &&
307 ((reg & ~3) == PCI_BASE_ADDRESS_0))
308 return 0;
309
310 return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);
311}
312
313static const struct pci_raw_ops ce4100_pci_conf = {
314 .read = ce4100_conf_read,
315 .write = ce4100_conf_write,
316};
317
318int __init ce4100_pci_init(void)
319{
320 init_sim_regs();
321 raw_pci_ops = &ce4100_pci_conf;
322 /* Indicate caller that it should invoke pci_legacy_init() */
323 return 1;
324}
325

source code of linux/arch/x86/pci/ce4100.c