xref: /openbmc/linux/arch/x86/pci/ce4100.c (revision f9a82c48)
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 /*
69  * All read/write functions are called with pci_config_lock held.
70  */
71 static void reg_init(struct sim_dev_reg *reg)
72 {
73 	pci_direct_conf1.read(0, 1, reg->dev_func, reg->reg, 4,
74 			      &reg->sim_reg.value);
75 }
76 
77 static void reg_read(struct sim_dev_reg *reg, u32 *value)
78 {
79 	*value = reg->sim_reg.value;
80 }
81 
82 static void reg_write(struct sim_dev_reg *reg, u32 value)
83 {
84 	reg->sim_reg.value = (value & reg->sim_reg.mask) |
85 		(reg->sim_reg.value & ~reg->sim_reg.mask);
86 }
87 
88 static void sata_reg_init(struct sim_dev_reg *reg)
89 {
90 	pci_direct_conf1.read(0, 1, PCI_DEVFN(14, 0), 0x10, 4,
91 			      &reg->sim_reg.value);
92 	reg->sim_reg.value += 0x400;
93 }
94 
95 static void ehci_reg_read(struct sim_dev_reg *reg, u32 *value)
96 {
97 	reg_read(reg, value);
98 	if (*value != reg->sim_reg.mask)
99 		*value |= 0x100;
100 }
101 
102 void sata_revid_init(struct sim_dev_reg *reg)
103 {
104 	reg->sim_reg.value = 0x01060100;
105 	reg->sim_reg.mask = 0;
106 }
107 
108 static void sata_revid_read(struct sim_dev_reg *reg, u32 *value)
109 {
110 	reg_read(reg, value);
111 }
112 
113 static void reg_noirq_read(struct sim_dev_reg *reg, u32 *value)
114 {
115 	/* force interrupt pin value to 0 */
116 	*value = reg->sim_reg.value & 0xfff00ff;
117 }
118 
119 static struct sim_dev_reg bus1_fixups[] = {
120 	DEFINE_REG(2, 0, 0x10, (16*MB), reg_init, reg_read, reg_write)
121 	DEFINE_REG(2, 0, 0x14, (256), reg_init, reg_read, reg_write)
122 	DEFINE_REG(2, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
123 	DEFINE_REG(3, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
124 	DEFINE_REG(4, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
125 	DEFINE_REG(4, 1, 0x10, (128*KB), reg_init, reg_read, reg_write)
126 	DEFINE_REG(6, 0, 0x10, (512*KB), reg_init, reg_read, reg_write)
127 	DEFINE_REG(6, 1, 0x10, (512*KB), reg_init, reg_read, reg_write)
128 	DEFINE_REG(6, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
129 	DEFINE_REG(8, 0, 0x10, (1*MB), reg_init, reg_read, reg_write)
130 	DEFINE_REG(8, 1, 0x10, (64*KB), reg_init, reg_read, reg_write)
131 	DEFINE_REG(8, 2, 0x10, (64*KB), reg_init, reg_read, reg_write)
132 	DEFINE_REG(9, 0, 0x10 , (1*MB), reg_init, reg_read, reg_write)
133 	DEFINE_REG(9, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
134 	DEFINE_REG(10, 0, 0x10, (256), reg_init, reg_read, reg_write)
135 	DEFINE_REG(10, 0, 0x14, (256*MB), reg_init, reg_read, reg_write)
136 	DEFINE_REG(11, 0, 0x10, (256), reg_init, reg_read, reg_write)
137 	DEFINE_REG(11, 0, 0x14, (256), reg_init, reg_read, reg_write)
138 	DEFINE_REG(11, 1, 0x10, (256), reg_init, reg_read, reg_write)
139 	DEFINE_REG(11, 2, 0x10, (256), reg_init, reg_read, reg_write)
140 	DEFINE_REG(11, 2, 0x14, (256), reg_init, reg_read, reg_write)
141 	DEFINE_REG(11, 2, 0x18, (256), reg_init, reg_read, reg_write)
142 	DEFINE_REG(11, 3, 0x10, (256), reg_init, reg_read, reg_write)
143 	DEFINE_REG(11, 3, 0x14, (256), reg_init, reg_read, reg_write)
144 	DEFINE_REG(11, 4, 0x10, (256), reg_init, reg_read, reg_write)
145 	DEFINE_REG(11, 5, 0x10, (64*KB), reg_init, reg_read, reg_write)
146 	DEFINE_REG(11, 6, 0x10, (256), reg_init, reg_read, reg_write)
147 	DEFINE_REG(11, 7, 0x10, (64*KB), reg_init, reg_read, reg_write)
148 	DEFINE_REG(11, 7, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
149 	DEFINE_REG(12, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
150 	DEFINE_REG(12, 0, 0x14, (256), reg_init, reg_read, reg_write)
151 	DEFINE_REG(12, 1, 0x10, (1024), reg_init, reg_read, reg_write)
152 	DEFINE_REG(13, 0, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
153 	DEFINE_REG(13, 1, 0x10, (32*KB), reg_init, ehci_reg_read, reg_write)
154 	DEFINE_REG(14, 0, 0x8,  0, sata_revid_init, sata_revid_read, 0)
155 	DEFINE_REG(14, 0, 0x10, 0, reg_init, reg_read, reg_write)
156 	DEFINE_REG(14, 0, 0x14, 0, reg_init, reg_read, reg_write)
157 	DEFINE_REG(14, 0, 0x18, 0, reg_init, reg_read, reg_write)
158 	DEFINE_REG(14, 0, 0x1C, 0, reg_init, reg_read, reg_write)
159 	DEFINE_REG(14, 0, 0x20, 0, reg_init, reg_read, reg_write)
160 	DEFINE_REG(14, 0, 0x24, (0x200), sata_reg_init, reg_read, reg_write)
161 	DEFINE_REG(15, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
162 	DEFINE_REG(15, 0, 0x14, (64*KB), reg_init, reg_read, reg_write)
163 	DEFINE_REG(16, 0, 0x10, (64*KB), reg_init, reg_read, reg_write)
164 	DEFINE_REG(16, 0, 0x14, (64*MB), reg_init, reg_read, reg_write)
165 	DEFINE_REG(16, 0, 0x18, (64*MB), reg_init, reg_read, reg_write)
166 	DEFINE_REG(16, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
167 	DEFINE_REG(17, 0, 0x10, (128*KB), reg_init, reg_read, reg_write)
168 	DEFINE_REG(18, 0, 0x10, (1*KB), reg_init, reg_read, reg_write)
169 	DEFINE_REG(18, 0, 0x3c, 256, reg_init, reg_noirq_read, reg_write)
170 };
171 
172 static void __init init_sim_regs(void)
173 {
174 	int i;
175 
176 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
177 		if (bus1_fixups[i].init)
178 			bus1_fixups[i].init(&bus1_fixups[i]);
179 	}
180 }
181 
182 static inline void extract_bytes(u32 *value, int reg, int len)
183 {
184 	uint32_t mask;
185 
186 	*value >>= ((reg & 3) * 8);
187 	mask = 0xFFFFFFFF >> ((4 - len) * 8);
188 	*value &= mask;
189 }
190 
191 int bridge_read(unsigned int devfn, int reg, int len, u32 *value)
192 {
193 	u32 av_bridge_base, av_bridge_limit;
194 	int retval = 0;
195 
196 	switch (reg) {
197 	/* Make BARs appear to not request any memory. */
198 	case PCI_BASE_ADDRESS_0:
199 	case PCI_BASE_ADDRESS_0 + 1:
200 	case PCI_BASE_ADDRESS_0 + 2:
201 	case PCI_BASE_ADDRESS_0 + 3:
202 		*value = 0;
203 		break;
204 
205 		/* Since subordinate bus number register is hardwired
206 		 * to zero and read only, so do the simulation.
207 		 */
208 	case PCI_PRIMARY_BUS:
209 		if (len == 4)
210 			*value = 0x00010100;
211 		break;
212 
213 	case PCI_SUBORDINATE_BUS:
214 		*value = 1;
215 		break;
216 
217 	case PCI_MEMORY_BASE:
218 	case PCI_MEMORY_LIMIT:
219 		/* Get the A/V bridge base address. */
220 		pci_direct_conf1.read(0, 0, devfn,
221 				PCI_BASE_ADDRESS_0, 4, &av_bridge_base);
222 
223 		av_bridge_limit = av_bridge_base + (512*MB - 1);
224 		av_bridge_limit >>= 16;
225 		av_bridge_limit &= 0xFFF0;
226 
227 		av_bridge_base >>= 16;
228 		av_bridge_base &= 0xFFF0;
229 
230 		if (reg == PCI_MEMORY_LIMIT)
231 			*value = av_bridge_limit;
232 		else if (len == 2)
233 			*value = av_bridge_base;
234 		else
235 			*value = (av_bridge_limit << 16) | av_bridge_base;
236 		break;
237 		/* Make prefetchable memory limit smaller than prefetchable
238 		 * memory base, so not claim prefetchable memory space.
239 		 */
240 	case PCI_PREF_MEMORY_BASE:
241 		*value = 0xFFF0;
242 		break;
243 	case PCI_PREF_MEMORY_LIMIT:
244 		*value = 0x0;
245 		break;
246 		/* Make IO limit smaller than IO base, so not claim IO space. */
247 	case PCI_IO_BASE:
248 		*value = 0xF0;
249 		break;
250 	case PCI_IO_LIMIT:
251 		*value = 0;
252 		break;
253 	default:
254 		retval = 1;
255 	}
256 	return retval;
257 }
258 
259 static int ce4100_bus1_read(unsigned int devfn, int reg, int len, u32 *value)
260 {
261 	unsigned long flags;
262 	int i;
263 
264 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
265 		if (bus1_fixups[i].dev_func == devfn &&
266 		    bus1_fixups[i].reg == (reg & ~3) &&
267 		    bus1_fixups[i].read) {
268 
269 			raw_spin_lock_irqsave(&pci_config_lock, flags);
270 			bus1_fixups[i].read(&(bus1_fixups[i]), value);
271 			raw_spin_unlock_irqrestore(&pci_config_lock, flags);
272 			extract_bytes(value, reg, len);
273 			return 0;
274 		}
275 	}
276 	return -1;
277 }
278 
279 static int ce4100_conf_read(unsigned int seg, unsigned int bus,
280 			    unsigned int devfn, int reg, int len, u32 *value)
281 {
282 	WARN_ON(seg);
283 
284 	if (bus == 1 && !ce4100_bus1_read(devfn, reg, len, value))
285 		return 0;
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_bus1_write(unsigned int devfn, int reg, int len, u32 value)
295 {
296 	unsigned long flags;
297 	int i;
298 
299 	for (i = 0; i < ARRAY_SIZE(bus1_fixups); i++) {
300 		if (bus1_fixups[i].dev_func == devfn &&
301 		    bus1_fixups[i].reg == (reg & ~3) &&
302 		    bus1_fixups[i].write) {
303 
304 			raw_spin_lock_irqsave(&pci_config_lock, flags);
305 			bus1_fixups[i].write(&(bus1_fixups[i]), value);
306 			raw_spin_unlock_irqrestore(&pci_config_lock, flags);
307 			return 0;
308 		}
309 	}
310 	return -1;
311 }
312 
313 static int ce4100_conf_write(unsigned int seg, unsigned int bus,
314 			     unsigned int devfn, int reg, int len, u32 value)
315 {
316 	WARN_ON(seg);
317 
318 	if (bus == 1 && !ce4100_bus1_write(devfn, reg, len, value))
319 		return 0;
320 
321 	/* Discard writes to A/V bridge BAR. */
322 	if (bus == 0 && PCI_DEVFN(1, 0) == devfn &&
323 	    ((reg & ~3) == PCI_BASE_ADDRESS_0))
324 		return 0;
325 
326 	return pci_direct_conf1.write(seg, bus, devfn, reg, len, value);
327 }
328 
329 static const struct pci_raw_ops ce4100_pci_conf = {
330 	.read	= ce4100_conf_read,
331 	.write	= ce4100_conf_write,
332 };
333 
334 int __init ce4100_pci_init(void)
335 {
336 	init_sim_regs();
337 	raw_pci_ops = &ce4100_pci_conf;
338 	/* Indicate caller that it should invoke pci_legacy_init() */
339 	return 1;
340 }
341