xref: /openbmc/linux/arch/x86/pci/ce4100.c (revision d7a3d85e)
1 /*
2  *  GPL LICENSE SUMMARY
3  *
4  *  Copyright(c) 2010 Intel Corporation. All rights reserved.
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of version 2 of the GNU General Public License as
8  *  published by the Free Software Foundation.
9  *
10  *  This program is distributed in the hope that it will be useful, but
11  *  WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  *  General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18  *  The full GNU General Public License is included in this distribution
19  *  in the file called LICENSE.GPL.
20  *
21  *  Contact Information:
22  *    Intel Corporation
23  *    2200 Mission College Blvd.
24  *    Santa Clara, CA  97052
25  *
26  * This provides access methods for PCI registers that mis-behave on
27  * the CE4100. Each register can be assigned a private init, read and
28  * write routine. The exception to this is the bridge device.  The
29  * bridge device is the only device on bus zero (0) that requires any
30  * fixup so it is a special case ATM
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/pci.h>
35 #include <linux/init.h>
36 
37 #include <asm/ce4100.h>
38 #include <asm/pci_x86.h>
39 
40 struct sim_reg {
41 	u32 value;
42 	u32 mask;
43 };
44 
45 struct sim_dev_reg {
46 	int dev_func;
47 	int reg;
48 	void (*init)(struct sim_dev_reg *reg);
49 	void (*read)(struct sim_dev_reg *reg, u32 *value);
50 	void (*write)(struct sim_dev_reg *reg, u32 value);
51 	struct sim_reg sim_reg;
52 };
53 
54 struct sim_reg_op {
55 	void (*init)(struct sim_dev_reg *reg);
56 	void (*read)(struct sim_dev_reg *reg, u32 value);
57 	void (*write)(struct sim_dev_reg *reg, u32 value);
58 };
59 
60 #define MB (1024 * 1024)
61 #define KB (1024)
62 #define SIZE_TO_MASK(size) (~(size - 1))
63 
64 #define DEFINE_REG(device, func, offset, size, init_op, read_op, write_op)\
65 { PCI_DEVFN(device, func), offset, init_op, read_op, write_op,\
66 	{0, SIZE_TO_MASK(size)} },
67 
68 static void reg_init(struct sim_dev_reg *reg)
69 {
70 	pci_direct_conf1.read(0, 1, reg->dev_func, reg->reg, 4,
71 			      &reg->sim_reg.value);
72 }
73 
74 static void reg_read(struct sim_dev_reg *reg, u32 *value)
75 {
76 	unsigned long flags;
77 
78 	raw_spin_lock_irqsave(&pci_config_lock, flags);
79 	*value = reg->sim_reg.value;
80 	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
81 }
82 
83 static void reg_write(struct sim_dev_reg *reg, u32 value)
84 {
85 	unsigned long flags;
86 
87 	raw_spin_lock_irqsave(&pci_config_lock, flags);
88 	reg->sim_reg.value = (value & reg->sim_reg.mask) |
89 		(reg->sim_reg.value & ~reg->sim_reg.mask);
90 	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
91 }
92 
93 static void sata_reg_init(struct sim_dev_reg *reg)
94 {
95 	pci_direct_conf1.read(0, 1, PCI_DEVFN(14, 0), 0x10, 4,
96 			      &reg->sim_reg.value);
97 	reg->sim_reg.value += 0x400;
98 }
99 
100 static void ehci_reg_read(struct sim_dev_reg *reg, u32 *value)
101 {
102 	reg_read(reg, value);
103 	if (*value != reg->sim_reg.mask)
104 		*value |= 0x100;
105 }
106 
107 void sata_revid_init(struct sim_dev_reg *reg)
108 {
109 	reg->sim_reg.value = 0x01060100;
110 	reg->sim_reg.mask = 0;
111 }
112 
113 static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
114 {
115 	reg_read(reg, value);
116 }
117 
118 static void reg_noirq_read(struct sim_dev_reg *reg, u32 *value)
119 {
120 	unsigned long flags;
121 
122 	raw_spin_lock_irqsave(&pci_config_lock, flags);
123 	/* force interrupt pin value to 0 */
124 	*value = reg->sim_reg.value & 0xfff00ff;
125 	raw_spin_unlock_irqrestore(&pci_config_lock, flags);
126 }
127 
128 static struct sim_dev_reg bus1_fixups[] = {
129 	DEFINE_REG(2, 0, 0x10, (16*MB), reg_init, reg_read, reg_write)
130 	DEFINE_REG(2, 0, 0x14, (256), reg_init, reg_read, reg_write)
131 	DEFINE_REG(2, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
132 	DEFINE_REG(3, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
133 	DEFINE_REG(4, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
134 	DEFINE_REG(4, 1, 0x10, (128*KB), reg_init, reg_read, reg_write)
135 	DEFINE_REG(6, 0, 0x10, (512*KB), reg_init, reg_read, reg_write)
136 	DEFINE_REG(6, 1, 0x10, (512*KB), reg_init, reg_read, reg_write)
137 	DEFINE_REG(6, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
138 	DEFINE_REG(8, 0, 0x10, (1*MB), reg_init, reg_read, reg_write)
139 	DEFINE_REG(8, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
140 	DEFINE_REG(8, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
141 	DEFINE_REG(9, 0, 0x10 , (1*MB), reg_init, reg_read, reg_write)
142 	DEFINE_REG(9, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
143 	DEFINE_REG(10, 0, 0x10, (256), reg_init, reg_read, reg_write)
144 	DEFINE_REG(10, 0, 0x14, (256*MB), reg_init, reg_read, reg_write)
145 	DEFINE_REG(11, 0, 0x10, (256), reg_init, reg_read, reg_write)
146 	DEFINE_REG(11, 0, 0x14, (256), reg_init, reg_read, reg_write)
147 	DEFINE_REG(11, 1, 0x10, (256), reg_init, reg_read, reg_write)
148 	DEFINE_REG(11, 2, 0x10, (256), reg_init, reg_read, reg_write)
149 	DEFINE_REG(11, 2, 0x14, (256), reg_init, reg_read, reg_write)
150 	DEFINE_REG(11, 2, 0x18, (256), reg_init, reg_read, reg_write)
151 	DEFINE_REG(11, 3, 0x10, (256), reg_init, reg_read, reg_write)
152 	DEFINE_REG(11, 3, 0x14, (256), reg_init, reg_read, reg_write)
153 	DEFINE_REG(11, 4, 0x10, (256), reg_init, reg_read, reg_write)
154 	DEFINE_REG(11, 5, 0x10, (64*KB), reg_init, reg_read, reg_write)
155 	DEFINE_REG(11, 6, 0x10, (256), reg_init, reg_read, reg_write)
156 	DEFINE_REG(11, 7, 0x10, (64*KB), reg_init, reg_read, reg_write)
157 	DEFINE_REG(11, 7, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
158 	DEFINE_REG(12, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
159 	DEFINE_REG(12, 0, 0x14, (256), reg_init, reg_read, reg_write)
160 	DEFINE_REG(12, 1, 0x10, (1024), reg_init, reg_read, reg_write)
161 	DEFINE_REG(13, 0, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
162 	DEFINE_REG(13, 1, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
163 	DEFINE_REG(14, 0, 0x8,  0, sata_revid_init, sata_revid_read, 0)
164 	DEFINE_REG(14, 0, 0x10, 0, reg_init, reg_read, reg_write)
165 	DEFINE_REG(14, 0, 0x14, 0, reg_init, reg_read, reg_write)
166 	DEFINE_REG(14, 0, 0x18, 0, reg_init, reg_read, reg_write)
167 	DEFINE_REG(14, 0, 0x1C, 0, reg_init, reg_read, reg_write)
168 	DEFINE_REG(14, 0, 0x20, 0, reg_init, reg_read, reg_write)
169 	DEFINE_REG(14, 0, 0x24, (0x200), sata_reg_init, reg_read, reg_write)
170 	DEFINE_REG(15, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
171 	DEFINE_REG(15, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
172 	DEFINE_REG(16, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
173 	DEFINE_REG(16, 0, 0x14, (64*MB), reg_init, reg_read, reg_write)
174 	DEFINE_REG(16, 0, 0x18, (64*MB), reg_init, reg_read, reg_write)
175 	DEFINE_REG(16, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
176 	DEFINE_REG(17, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
177 	DEFINE_REG(18, 0, 0x10, (1*KB), reg_init, reg_read, reg_write)
178 	DEFINE_REG(18, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
179 };
180 
181 static void __init init_sim_regs(void)
182 {
183 	int i;
184 
185 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
186 		if (bus1_fixups[i].init)
187 			bus1_fixups[i].init(&bus1_fixups[i]);
188 	}
189 }
190 
191 static inline void extract_bytes(u32 *value, int reg, int len)
192 {
193 	uint32_t mask;
194 
195 	*value >>= ((reg & 3) * 8);
196 	mask = 0xFFFFFFFF >> ((4 - len) * 8);
197 	*value &= mask;
198 }
199 
200 int bridge_read(unsigned int devfn, int reg, int len, u32 *value)
201 {
202 	u32 av_bridge_base, av_bridge_limit;
203 	int retval = 0;
204 
205 	switch (reg) {
206 	/* Make BARs appear to not request any memory. */
207 	case PCI_BASE_ADDRESS_0:
208 	case PCI_BASE_ADDRESS_0 + 1:
209 	case PCI_BASE_ADDRESS_0 + 2:
210 	case PCI_BASE_ADDRESS_0 + 3:
211 		*value = 0;
212 		break;
213 
214 		/* Since subordinate bus number register is hardwired
215 		 * to zero and read only, so do the simulation.
216 		 */
217 	case PCI_PRIMARY_BUS:
218 		if (len == 4)
219 			*value = 0x00010100;
220 		break;
221 
222 	case PCI_SUBORDINATE_BUS:
223 		*value = 1;
224 		break;
225 
226 	case PCI_MEMORY_BASE:
227 	case PCI_MEMORY_LIMIT:
228 		/* Get the A/V bridge base address. */
229 		pci_direct_conf1.read(0, 0, devfn,
230 				PCI_BASE_ADDRESS_0, 4, &av_bridge_base);
231 
232 		av_bridge_limit = av_bridge_base + (512*MB - 1);
233 		av_bridge_limit >>= 16;
234 		av_bridge_limit &= 0xFFF0;
235 
236 		av_bridge_base >>= 16;
237 		av_bridge_base &= 0xFFF0;
238 
239 		if (reg == PCI_MEMORY_LIMIT)
240 			*value = av_bridge_limit;
241 		else if (len == 2)
242 			*value = av_bridge_base;
243 		else
244 			*value = (av_bridge_limit << 16) | av_bridge_base;
245 		break;
246 		/* Make prefetchable memory limit smaller than prefetchable
247 		 * memory base, so not claim prefetchable memory space.
248 		 */
249 	case PCI_PREF_MEMORY_BASE:
250 		*value = 0xFFF0;
251 		break;
252 	case PCI_PREF_MEMORY_LIMIT:
253 		*value = 0x0;
254 		break;
255 		/* Make IO limit smaller than IO base, so not claim IO space. */
256 	case PCI_IO_BASE:
257 		*value = 0xF0;
258 		break;
259 	case PCI_IO_LIMIT:
260 		*value = 0;
261 		break;
262 	default:
263 		retval = 1;
264 	}
265 	return retval;
266 }
267 
268 static int ce4100_conf_read(unsigned int seg, unsigned int bus,
269 			    unsigned int devfn, int reg, int len, u32 *value)
270 {
271 	int i;
272 
273 	WARN_ON(seg);
274 	if (bus == 1) {
275 		for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
276 			if (bus1_fixups[i].dev_func == devfn &&
277 			    bus1_fixups[i].reg == (reg & ~3) &&
278 			    bus1_fixups[i].read) {
279 				bus1_fixups[i].read(&(bus1_fixups[i]),
280 						    value);
281 				extract_bytes(value, reg, len);
282 				return 0;
283 			}
284 		}
285 	}
286 
287 	if (bus == 0 && (PCI_DEVFN(1, 0) == devfn) &&
288 	    !bridge_read(devfn, reg, len, value))
289 		return 0;
290 
291 	return pci_direct_conf1.read(seg, bus, devfn, reg, len, value);
292 }
293 
294 static int ce4100_conf_write(unsigned int seg, unsigned int bus,
295 			     unsigned int devfn, int reg, int len, u32 value)
296 {
297 	int i;
298 
299 	WARN_ON(seg);
300 	if (bus == 1) {
301 		for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
302 			if (bus1_fixups[i].dev_func == devfn &&
303 			    bus1_fixups[i].reg == (reg & ~3) &&
304 			    bus1_fixups[i].write) {
305 				bus1_fixups[i].write(&(bus1_fixups[i]),
306 						     value);
307 				return 0;
308 			}
309 		}
310 	}
311 
312 	/* Discard writes to A/V bridge BAR. */
313 	if (bus == 0 && PCI_DEVFN(1, 0) == devfn &&
314 	    ((reg & ~3) == PCI_BASE_ADDRESS_0))
315 		return 0;
316 
317 	return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);
318 }
319 
320 static const struct pci_raw_ops ce4100_pci_conf = {
321 	.read =	ce4100_conf_read,
322 	.write = ce4100_conf_write,
323 };
324 
325 int __init ce4100_pci_init(void)
326 {
327 	init_sim_regs();
328 	raw_pci_ops = &ce4100_pci_conf;
329 	/* Indicate caller that it should invoke pci_legacy_init() */
330 	return 1;
331 }
332