xref: /linux/arch/x86/pci/ce4100.c (revision 561add0da6d3d07c9bccb0832fb6ed5619167d26)
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 struct 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  */
55 static 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 
61 static void reg_read(struct sim_dev_reg *reg, u32 *value)
62 {
63 	*value = reg->sim_reg.value;
64 }
65 
66 static 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 
72 static 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 
79 static 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 
86 static void sata_revid_init(struct sim_dev_reg *reg)
87 {
88 	reg->sim_reg.value = 0x01060100;
89 	reg->sim_reg.mask = 0;
90 }
91 
92 static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
93 {
94 	reg_read(reg, value);
95 }
96 
97 static 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 
103 static 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 
156 static 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 
166 static 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 
175 static 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 
243 static 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 
263 static 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 
278 static 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 
297 static 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 
313 static const struct pci_raw_ops ce4100_pci_conf = {
314 	.read	= ce4100_conf_read,
315 	.write	= ce4100_conf_write,
316 };
317 
318 int __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