xref: /linux/arch/x86/pci/ce4100.c (revision e7c3696d4692e8046d25f6e63f983e934e12f2c5)
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 
24 struct sim_reg {
25 	u32 value;
26 	u32 mask;
27 };
28 
29 struct 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 
38 #define MB (1024 * 1024)
39 #define KB (1024)
40 #define SIZE_TO_MASK(size) (~(size - 1))
41 
42 #define DEFINE_REG(device, func, offset, size, init_op, read_op, write_op)\
43 { PCI_DEVFN(device, func), offset, init_op, read_op, write_op,\
44 	{0, SIZE_TO_MASK(size)} },
45 
46 /*
47  * All read/write functions are called with pci_config_lock held.
48  */
49 static void reg_init(struct sim_dev_reg *reg)
50 {
51 	pci_direct_conf1.read(0, 1, reg->dev_func, reg->reg, 4,
52 			      &reg->sim_reg.value);
53 }
54 
55 static void reg_read(struct sim_dev_reg *reg, u32 *value)
56 {
57 	*value = reg->sim_reg.value;
58 }
59 
60 static void reg_write(struct sim_dev_reg *reg, u32 value)
61 {
62 	reg->sim_reg.value = (value & reg->sim_reg.mask) |
63 		(reg->sim_reg.value & ~reg->sim_reg.mask);
64 }
65 
66 static void sata_reg_init(struct sim_dev_reg *reg)
67 {
68 	pci_direct_conf1.read(0, 1, PCI_DEVFN(14, 0), 0x10, 4,
69 			      &reg->sim_reg.value);
70 	reg->sim_reg.value += 0x400;
71 }
72 
73 static void ehci_reg_read(struct sim_dev_reg *reg, u32 *value)
74 {
75 	reg_read(reg, value);
76 	if (*value != reg->sim_reg.mask)
77 		*value |= 0x100;
78 }
79 
80 static void sata_revid_init(struct sim_dev_reg *reg)
81 {
82 	reg->sim_reg.value = 0x01060100;
83 	reg->sim_reg.mask = 0;
84 }
85 
86 static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
87 {
88 	reg_read(reg, value);
89 }
90 
91 static void reg_noirq_read(struct sim_dev_reg *reg, u32 *value)
92 {
93 	/* force interrupt pin value to 0 */
94 	*value = reg->sim_reg.value & 0xfff00ff;
95 }
96 
97 static struct sim_dev_reg bus1_fixups[] = {
98 	DEFINE_REG(2, 0, 0x10, (16*MB), reg_init, reg_read, reg_write)
99 	DEFINE_REG(2, 0, 0x14, (256), reg_init, reg_read, reg_write)
100 	DEFINE_REG(2, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
101 	DEFINE_REG(3, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
102 	DEFINE_REG(4, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
103 	DEFINE_REG(4, 1, 0x10, (128*KB), reg_init, reg_read, reg_write)
104 	DEFINE_REG(6, 0, 0x10, (512*KB), reg_init, reg_read, reg_write)
105 	DEFINE_REG(6, 1, 0x10, (512*KB), reg_init, reg_read, reg_write)
106 	DEFINE_REG(6, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
107 	DEFINE_REG(8, 0, 0x10, (1*MB), reg_init, reg_read, reg_write)
108 	DEFINE_REG(8, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
109 	DEFINE_REG(8, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
110 	DEFINE_REG(9, 0, 0x10 , (1*MB), reg_init, reg_read, reg_write)
111 	DEFINE_REG(9, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
112 	DEFINE_REG(10, 0, 0x10, (256), reg_init, reg_read, reg_write)
113 	DEFINE_REG(10, 0, 0x14, (256*MB), reg_init, reg_read, reg_write)
114 	DEFINE_REG(11, 0, 0x10, (256), reg_init, reg_read, reg_write)
115 	DEFINE_REG(11, 0, 0x14, (256), reg_init, reg_read, reg_write)
116 	DEFINE_REG(11, 1, 0x10, (256), reg_init, reg_read, reg_write)
117 	DEFINE_REG(11, 2, 0x10, (256), reg_init, reg_read, reg_write)
118 	DEFINE_REG(11, 2, 0x14, (256), reg_init, reg_read, reg_write)
119 	DEFINE_REG(11, 2, 0x18, (256), reg_init, reg_read, reg_write)
120 	DEFINE_REG(11, 3, 0x10, (256), reg_init, reg_read, reg_write)
121 	DEFINE_REG(11, 3, 0x14, (256), reg_init, reg_read, reg_write)
122 	DEFINE_REG(11, 4, 0x10, (256), reg_init, reg_read, reg_write)
123 	DEFINE_REG(11, 5, 0x10, (64*KB), reg_init, reg_read, reg_write)
124 	DEFINE_REG(11, 6, 0x10, (256), reg_init, reg_read, reg_write)
125 	DEFINE_REG(11, 7, 0x10, (64*KB), reg_init, reg_read, reg_write)
126 	DEFINE_REG(11, 7, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
127 	DEFINE_REG(12, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
128 	DEFINE_REG(12, 0, 0x14, (256), reg_init, reg_read, reg_write)
129 	DEFINE_REG(12, 1, 0x10, (1024), reg_init, reg_read, reg_write)
130 	DEFINE_REG(13, 0, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
131 	DEFINE_REG(13, 1, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
132 	DEFINE_REG(14, 0, 0x8,  0, sata_revid_init, sata_revid_read, 0)
133 	DEFINE_REG(14, 0, 0x10, 0, reg_init, reg_read, reg_write)
134 	DEFINE_REG(14, 0, 0x14, 0, reg_init, reg_read, reg_write)
135 	DEFINE_REG(14, 0, 0x18, 0, reg_init, reg_read, reg_write)
136 	DEFINE_REG(14, 0, 0x1C, 0, reg_init, reg_read, reg_write)
137 	DEFINE_REG(14, 0, 0x20, 0, reg_init, reg_read, reg_write)
138 	DEFINE_REG(14, 0, 0x24, (0x200), sata_reg_init, reg_read, reg_write)
139 	DEFINE_REG(15, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
140 	DEFINE_REG(15, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
141 	DEFINE_REG(16, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
142 	DEFINE_REG(16, 0, 0x14, (64*MB), reg_init, reg_read, reg_write)
143 	DEFINE_REG(16, 0, 0x18, (64*MB), reg_init, reg_read, reg_write)
144 	DEFINE_REG(16, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
145 	DEFINE_REG(17, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
146 	DEFINE_REG(18, 0, 0x10, (1*KB), reg_init, reg_read, reg_write)
147 	DEFINE_REG(18, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
148 };
149 
150 static void __init init_sim_regs(void)
151 {
152 	int i;
153 
154 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
155 		if (bus1_fixups[i].init)
156 			bus1_fixups[i].init(&bus1_fixups[i]);
157 	}
158 }
159 
160 static inline void extract_bytes(u32 *value, int reg, int len)
161 {
162 	uint32_t mask;
163 
164 	*value >>= ((reg & 3) * 8);
165 	mask = 0xFFFFFFFF >> ((4 - len) * 8);
166 	*value &= mask;
167 }
168 
169 static int bridge_read(unsigned int devfn, int reg, int len, u32 *value)
170 {
171 	u32 av_bridge_base, av_bridge_limit;
172 	int retval = 0;
173 
174 	switch (reg) {
175 	/* Make BARs appear to not request any memory. */
176 	case PCI_BASE_ADDRESS_0:
177 	case PCI_BASE_ADDRESS_0 + 1:
178 	case PCI_BASE_ADDRESS_0 + 2:
179 	case PCI_BASE_ADDRESS_0 + 3:
180 		*value = 0;
181 		break;
182 
183 		/* Since subordinate bus number register is hardwired
184 		 * to zero and read only, so do the simulation.
185 		 */
186 	case PCI_PRIMARY_BUS:
187 		if (len == 4)
188 			*value = 0x00010100;
189 		break;
190 
191 	case PCI_SUBORDINATE_BUS:
192 		*value = 1;
193 		break;
194 
195 	case PCI_MEMORY_BASE:
196 	case PCI_MEMORY_LIMIT:
197 		/* Get the A/V bridge base address. */
198 		pci_direct_conf1.read(0, 0, devfn,
199 				PCI_BASE_ADDRESS_0, 4, &av_bridge_base);
200 
201 		av_bridge_limit = av_bridge_base + (512*MB - 1);
202 		av_bridge_limit >>= 16;
203 		av_bridge_limit &= 0xFFF0;
204 
205 		av_bridge_base >>= 16;
206 		av_bridge_base &= 0xFFF0;
207 
208 		if (reg == PCI_MEMORY_LIMIT)
209 			*value = av_bridge_limit;
210 		else if (len == 2)
211 			*value = av_bridge_base;
212 		else
213 			*value = (av_bridge_limit << 16) | av_bridge_base;
214 		break;
215 		/* Make prefetchable memory limit smaller than prefetchable
216 		 * memory base, so not claim prefetchable memory space.
217 		 */
218 	case PCI_PREF_MEMORY_BASE:
219 		*value = 0xFFF0;
220 		break;
221 	case PCI_PREF_MEMORY_LIMIT:
222 		*value = 0x0;
223 		break;
224 		/* Make IO limit smaller than IO base, so not claim IO space. */
225 	case PCI_IO_BASE:
226 		*value = 0xF0;
227 		break;
228 	case PCI_IO_LIMIT:
229 		*value = 0;
230 		break;
231 	default:
232 		retval = 1;
233 	}
234 	return retval;
235 }
236 
237 static int ce4100_bus1_read(unsigned int devfn, int reg, int len, u32 *value)
238 {
239 	unsigned long flags;
240 	int i;
241 
242 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
243 		if (bus1_fixups[i].dev_func == devfn &&
244 		    bus1_fixups[i].reg == (reg & ~3) &&
245 		    bus1_fixups[i].read) {
246 
247 			raw_spin_lock_irqsave(&pci_config_lock, flags);
248 			bus1_fixups[i].read(&(bus1_fixups[i]), value);
249 			raw_spin_unlock_irqrestore(&pci_config_lock, flags);
250 			extract_bytes(value, reg, len);
251 			return 0;
252 		}
253 	}
254 	return -1;
255 }
256 
257 static int ce4100_conf_read(unsigned int seg, unsigned int bus,
258 			    unsigned int devfn, int reg, int len, u32 *value)
259 {
260 	WARN_ON(seg);
261 
262 	if (bus == 1 && !ce4100_bus1_read(devfn, reg, len, value))
263 		return 0;
264 
265 	if (bus == 0 && (PCI_DEVFN(1, 0) == devfn) &&
266 	    !bridge_read(devfn, reg, len, value))
267 		return 0;
268 
269 	return pci_direct_conf1.read(seg, bus, devfn, reg, len, value);
270 }
271 
272 static int ce4100_bus1_write(unsigned int devfn, int reg, int len, u32 value)
273 {
274 	unsigned long flags;
275 	int i;
276 
277 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
278 		if (bus1_fixups[i].dev_func == devfn &&
279 		    bus1_fixups[i].reg == (reg & ~3) &&
280 		    bus1_fixups[i].write) {
281 
282 			raw_spin_lock_irqsave(&pci_config_lock, flags);
283 			bus1_fixups[i].write(&(bus1_fixups[i]), value);
284 			raw_spin_unlock_irqrestore(&pci_config_lock, flags);
285 			return 0;
286 		}
287 	}
288 	return -1;
289 }
290 
291 static int ce4100_conf_write(unsigned int seg, unsigned int bus,
292 			     unsigned int devfn, int reg, int len, u32 value)
293 {
294 	WARN_ON(seg);
295 
296 	if (bus == 1 && !ce4100_bus1_write(devfn, reg, len, value))
297 		return 0;
298 
299 	/* Discard writes to A/V bridge BAR. */
300 	if (bus == 0 && PCI_DEVFN(1, 0) == devfn &&
301 	    ((reg & ~3) == PCI_BASE_ADDRESS_0))
302 		return 0;
303 
304 	return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);
305 }
306 
307 static const struct pci_raw_ops ce4100_pci_conf = {
308 	.read	= ce4100_conf_read,
309 	.write	= ce4100_conf_write,
310 };
311 
312 int __init ce4100_pci_init(void)
313 {
314 	init_sim_regs();
315 	raw_pci_ops = &ce4100_pci_conf;
316 	/* Indicate caller that it should invoke pci_legacy_init() */
317 	return 1;
318 }
319