1 /*
2  * Copyright 2011 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 #include "mxms.h"
25 
26 #include <core/option.h>
27 #include <subdev/bios.h>
28 #include <subdev/bios/mxm.h>
29 #include <subdev/i2c.h>
30 
31 static bool
32 mxm_shadow_rom_fetch(struct nvkm_i2c_bus *bus, u8 addr,
33 		     u8 offset, u8 size, u8 *data)
34 {
35 	struct i2c_msg msgs[] = {
36 		{ .addr = addr, .flags = 0, .len = 1, .buf = &offset },
37 		{ .addr = addr, .flags = I2C_M_RD, .len = size, .buf = data, },
38 	};
39 
40 	return i2c_transfer(&bus->i2c, msgs, 2) == 2;
41 }
42 
43 static bool
44 mxm_shadow_rom(struct nvkm_mxm *mxm, u8 version)
45 {
46 	struct nvkm_device *device = mxm->subdev.device;
47 	struct nvkm_bios *bios = device->bios;
48 	struct nvkm_i2c *i2c = device->i2c;
49 	struct nvkm_i2c_bus *bus = NULL;
50 	u8 i2cidx, mxms[6], addr, size;
51 
52 	i2cidx = mxm_ddc_map(bios, 1 /* LVDS_DDC */) & 0x0f;
53 	if (i2cidx < 0x0f)
54 		bus = nvkm_i2c_bus_find(i2c, i2cidx);
55 	if (!bus)
56 		return false;
57 
58 	addr = 0x54;
59 	if (!mxm_shadow_rom_fetch(bus, addr, 0, 6, mxms)) {
60 		addr = 0x56;
61 		if (!mxm_shadow_rom_fetch(bus, addr, 0, 6, mxms))
62 			return false;
63 	}
64 
65 	mxm->mxms = mxms;
66 	size = mxms_headerlen(mxm) + mxms_structlen(mxm);
67 	mxm->mxms = kmalloc(size, GFP_KERNEL);
68 
69 	if (mxm->mxms &&
70 	    mxm_shadow_rom_fetch(bus, addr, 0, size, mxm->mxms))
71 		return true;
72 
73 	kfree(mxm->mxms);
74 	mxm->mxms = NULL;
75 	return false;
76 }
77 
78 #if defined(CONFIG_ACPI)
79 static bool
80 mxm_shadow_dsm(struct nvkm_mxm *mxm, u8 version)
81 {
82 	struct nvkm_subdev *subdev = &mxm->subdev;
83 	struct nvkm_device *device = subdev->device;
84 	static char muid[] = {
85 		0x00, 0xA4, 0x04, 0x40, 0x7D, 0x91, 0xF2, 0x4C,
86 		0xB8, 0x9C, 0x79, 0xB6, 0x2F, 0xD5, 0x56, 0x65
87 	};
88 	u32 mxms_args[] = { 0x00000000 };
89 	union acpi_object argv4 = {
90 		.buffer.type = ACPI_TYPE_BUFFER,
91 		.buffer.length = sizeof(mxms_args),
92 		.buffer.pointer = (char *)mxms_args,
93 	};
94 	union acpi_object *obj;
95 	acpi_handle handle;
96 	int rev;
97 
98 	handle = ACPI_HANDLE(device->dev);
99 	if (!handle)
100 		return false;
101 
102 	/*
103 	 * spec says this can be zero to mean "highest revision", but
104 	 * of course there's at least one bios out there which fails
105 	 * unless you pass in exactly the version it supports..
106 	 */
107 	rev = (version & 0xf0) << 4 | (version & 0x0f);
108 	obj = acpi_evaluate_dsm(handle, muid, rev, 0x00000010, &argv4);
109 	if (!obj) {
110 		nvkm_debug(subdev, "DSM MXMS failed\n");
111 		return false;
112 	}
113 
114 	if (obj->type == ACPI_TYPE_BUFFER) {
115 		mxm->mxms = kmemdup(obj->buffer.pointer,
116 					 obj->buffer.length, GFP_KERNEL);
117 	} else if (obj->type == ACPI_TYPE_INTEGER) {
118 		nvkm_debug(subdev, "DSM MXMS returned 0x%llx\n",
119 			   obj->integer.value);
120 	}
121 
122 	ACPI_FREE(obj);
123 	return mxm->mxms != NULL;
124 }
125 #endif
126 
127 #if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
128 
129 #define WMI_WMMX_GUID "F6CB5C3C-9CAE-4EBD-B577-931EA32A2CC0"
130 
131 static u8
132 wmi_wmmx_mxmi(struct nvkm_mxm *mxm, u8 version)
133 {
134 	struct nvkm_subdev *subdev = &mxm->subdev;
135 	u32 mxmi_args[] = { 0x494D584D /* MXMI */, version, 0 };
136 	struct acpi_buffer args = { sizeof(mxmi_args), mxmi_args };
137 	struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
138 	union acpi_object *obj;
139 	acpi_status status;
140 
141 	status = wmi_evaluate_method(WMI_WMMX_GUID, 0, 0, &args, &retn);
142 	if (ACPI_FAILURE(status)) {
143 		nvkm_debug(subdev, "WMMX MXMI returned %d\n", status);
144 		return 0x00;
145 	}
146 
147 	obj = retn.pointer;
148 	if (obj->type == ACPI_TYPE_INTEGER) {
149 		version = obj->integer.value;
150 		nvkm_debug(subdev, "WMMX MXMI version %d.%d\n",
151 			   (version >> 4), version & 0x0f);
152 	} else {
153 		version = 0;
154 		nvkm_debug(subdev, "WMMX MXMI returned non-integer\n");
155 	}
156 
157 	kfree(obj);
158 	return version;
159 }
160 
161 static bool
162 mxm_shadow_wmi(struct nvkm_mxm *mxm, u8 version)
163 {
164 	struct nvkm_subdev *subdev = &mxm->subdev;
165 	u32 mxms_args[] = { 0x534D584D /* MXMS */, version, 0 };
166 	struct acpi_buffer args = { sizeof(mxms_args), mxms_args };
167 	struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
168 	union acpi_object *obj;
169 	acpi_status status;
170 
171 	if (!wmi_has_guid(WMI_WMMX_GUID)) {
172 		nvkm_debug(subdev, "WMMX GUID not found\n");
173 		return false;
174 	}
175 
176 	mxms_args[1] = wmi_wmmx_mxmi(mxm, 0x00);
177 	if (!mxms_args[1])
178 		mxms_args[1] = wmi_wmmx_mxmi(mxm, version);
179 	if (!mxms_args[1])
180 		return false;
181 
182 	status = wmi_evaluate_method(WMI_WMMX_GUID, 0, 0, &args, &retn);
183 	if (ACPI_FAILURE(status)) {
184 		nvkm_debug(subdev, "WMMX MXMS returned %d\n", status);
185 		return false;
186 	}
187 
188 	obj = retn.pointer;
189 	if (obj->type == ACPI_TYPE_BUFFER) {
190 		mxm->mxms = kmemdup(obj->buffer.pointer,
191 				    obj->buffer.length, GFP_KERNEL);
192 	}
193 
194 	kfree(obj);
195 	return mxm->mxms != NULL;
196 }
197 #endif
198 
199 static struct mxm_shadow_h {
200 	const char *name;
201 	bool (*exec)(struct nvkm_mxm *, u8 version);
202 } _mxm_shadow[] = {
203 	{ "ROM", mxm_shadow_rom },
204 #if defined(CONFIG_ACPI)
205 	{ "DSM", mxm_shadow_dsm },
206 #endif
207 #if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
208 	{ "WMI", mxm_shadow_wmi },
209 #endif
210 	{}
211 };
212 
213 static int
214 mxm_shadow(struct nvkm_mxm *mxm, u8 version)
215 {
216 	struct mxm_shadow_h *shadow = _mxm_shadow;
217 	do {
218 		nvkm_debug(&mxm->subdev, "checking %s\n", shadow->name);
219 		if (shadow->exec(mxm, version)) {
220 			if (mxms_valid(mxm))
221 				return 0;
222 			kfree(mxm->mxms);
223 			mxm->mxms = NULL;
224 		}
225 	} while ((++shadow)->name);
226 	return -ENOENT;
227 }
228 
229 static const struct nvkm_subdev_func
230 nvkm_mxm = {
231 };
232 
233 int
234 nvkm_mxm_new_(struct nvkm_device *device, int index, struct nvkm_mxm **pmxm)
235 {
236 	struct nvkm_bios *bios = device->bios;
237 	struct nvkm_mxm *mxm;
238 	u8  ver, len;
239 	u16 data;
240 
241 	if (!(mxm = *pmxm = kzalloc(sizeof(*mxm), GFP_KERNEL)))
242 		return -ENOMEM;
243 
244 	nvkm_subdev_ctor(&nvkm_mxm, device, index, &mxm->subdev);
245 
246 	data = mxm_table(bios, &ver, &len);
247 	if (!data || !(ver = nvbios_rd08(bios, data))) {
248 		nvkm_debug(&mxm->subdev, "no VBIOS data, nothing to do\n");
249 		return 0;
250 	}
251 
252 	nvkm_info(&mxm->subdev, "BIOS version %d.%d\n", ver >> 4, ver & 0x0f);
253 
254 	if (mxm_shadow(mxm, ver)) {
255 		nvkm_warn(&mxm->subdev, "failed to locate valid SIS\n");
256 #if 0
257 		/* we should, perhaps, fall back to some kind of limited
258 		 * mode here if the x86 vbios hasn't already done the
259 		 * work for us (so we prevent loading with completely
260 		 * whacked vbios tables).
261 		 */
262 		return -EINVAL;
263 #else
264 		return 0;
265 #endif
266 	}
267 
268 	nvkm_debug(&mxm->subdev, "MXMS Version %d.%d\n",
269 		   mxms_version(mxm) >> 8, mxms_version(mxm) & 0xff);
270 	mxms_foreach(mxm, 0, NULL, NULL);
271 
272 	if (nvkm_boolopt(device->cfgopt, "NvMXMDCB", true))
273 		mxm->action |= MXM_SANITISE_DCB;
274 	return 0;
275 }
276