1 /*
2  * Copyright (c) 2006 Intel Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Authors:
18  *    Eric Anholt <eric@anholt.net>
19  *
20  */
21 #include <drm/drmP.h>
22 #include <drm/drm.h>
23 #include "gma_drm.h"
24 #include "psb_drv.h"
25 #include "psb_intel_drv.h"
26 #include "psb_intel_reg.h"
27 #include "intel_bios.h"
28 
29 
30 static void *find_section(struct bdb_header *bdb, int section_id)
31 {
32 	u8 *base = (u8 *)bdb;
33 	int index = 0;
34 	u16 total, current_size;
35 	u8 current_id;
36 
37 	/* skip to first section */
38 	index += bdb->header_size;
39 	total = bdb->bdb_size;
40 
41 	/* walk the sections looking for section_id */
42 	while (index < total) {
43 		current_id = *(base + index);
44 		index++;
45 		current_size = *((u16 *)(base + index));
46 		index += 2;
47 		if (current_id == section_id)
48 			return base + index;
49 		index += current_size;
50 	}
51 
52 	return NULL;
53 }
54 
55 static void fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
56 			struct lvds_dvo_timing *dvo_timing)
57 {
58 	panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
59 		dvo_timing->hactive_lo;
60 	panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
61 		((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
62 	panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
63 		dvo_timing->hsync_pulse_width;
64 	panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
65 		((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
66 
67 	panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
68 		dvo_timing->vactive_lo;
69 	panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
70 		dvo_timing->vsync_off;
71 	panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
72 		dvo_timing->vsync_pulse_width;
73 	panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
74 		((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
75 	panel_fixed_mode->clock = dvo_timing->clock * 10;
76 	panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
77 
78 	/* Some VBTs have bogus h/vtotal values */
79 	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
80 		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
81 	if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
82 		panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
83 
84 	drm_mode_set_name(panel_fixed_mode);
85 }
86 
87 static void parse_backlight_data(struct drm_psb_private *dev_priv,
88 				struct bdb_header *bdb)
89 {
90 	struct bdb_lvds_backlight *vbt_lvds_bl = NULL;
91 	struct bdb_lvds_backlight *lvds_bl;
92 	u8 p_type = 0;
93 	void *bl_start = NULL;
94 	struct bdb_lvds_options *lvds_opts
95 				= find_section(bdb, BDB_LVDS_OPTIONS);
96 
97 	dev_priv->lvds_bl = NULL;
98 
99 	if (lvds_opts)
100 		p_type = lvds_opts->panel_type;
101 	else
102 		return;
103 
104 	bl_start = find_section(bdb, BDB_LVDS_BACKLIGHT);
105 	vbt_lvds_bl = (struct bdb_lvds_backlight *)(bl_start + 1) + p_type;
106 
107 	lvds_bl = kzalloc(sizeof(*vbt_lvds_bl), GFP_KERNEL);
108 	if (!lvds_bl) {
109 		dev_err(dev_priv->dev->dev, "out of memory for backlight data\n");
110 		return;
111 	}
112 	memcpy(lvds_bl, vbt_lvds_bl, sizeof(*vbt_lvds_bl));
113 	dev_priv->lvds_bl = lvds_bl;
114 }
115 
116 /* Try to find integrated panel data */
117 static void parse_lfp_panel_data(struct drm_psb_private *dev_priv,
118 			    struct bdb_header *bdb)
119 {
120 	struct bdb_lvds_options *lvds_options;
121 	struct bdb_lvds_lfp_data *lvds_lfp_data;
122 	struct bdb_lvds_lfp_data_entry *entry;
123 	struct lvds_dvo_timing *dvo_timing;
124 	struct drm_display_mode *panel_fixed_mode;
125 
126 	/* Defaults if we can't find VBT info */
127 	dev_priv->lvds_dither = 0;
128 	dev_priv->lvds_vbt = 0;
129 
130 	lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
131 	if (!lvds_options)
132 		return;
133 
134 	dev_priv->lvds_dither = lvds_options->pixel_dither;
135 	if (lvds_options->panel_type == 0xff)
136 		return;
137 
138 	lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
139 	if (!lvds_lfp_data)
140 		return;
141 
142 
143 	entry = &lvds_lfp_data->data[lvds_options->panel_type];
144 	dvo_timing = &entry->dvo_timing;
145 
146 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode),
147 				      GFP_KERNEL);
148 	if (panel_fixed_mode == NULL) {
149 		dev_err(dev_priv->dev->dev, "out of memory for fixed panel mode\n");
150 		return;
151 	}
152 
153 	dev_priv->lvds_vbt = 1;
154 	fill_detail_timing_data(panel_fixed_mode, dvo_timing);
155 
156 	if (panel_fixed_mode->htotal > 0 && panel_fixed_mode->vtotal > 0) {
157 		dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;
158 		drm_mode_debug_printmodeline(panel_fixed_mode);
159 	} else {
160 		dev_dbg(dev_priv->dev->dev, "ignoring invalid LVDS VBT\n");
161 		dev_priv->lvds_vbt = 0;
162 		kfree(panel_fixed_mode);
163 	}
164 	return;
165 }
166 
167 /* Try to find sdvo panel data */
168 static void parse_sdvo_panel_data(struct drm_psb_private *dev_priv,
169 		      struct bdb_header *bdb)
170 {
171 	struct bdb_sdvo_lvds_options *sdvo_lvds_options;
172 	struct lvds_dvo_timing *dvo_timing;
173 	struct drm_display_mode *panel_fixed_mode;
174 
175 	dev_priv->sdvo_lvds_vbt_mode = NULL;
176 
177 	sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
178 	if (!sdvo_lvds_options)
179 		return;
180 
181 	dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
182 	if (!dvo_timing)
183 		return;
184 
185 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
186 
187 	if (!panel_fixed_mode)
188 		return;
189 
190 	fill_detail_timing_data(panel_fixed_mode,
191 			dvo_timing + sdvo_lvds_options->panel_type);
192 
193 	dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode;
194 
195 	return;
196 }
197 
198 static void parse_general_features(struct drm_psb_private *dev_priv,
199 		       struct bdb_header *bdb)
200 {
201 	struct bdb_general_features *general;
202 
203 	/* Set sensible defaults in case we can't find the general block */
204 	dev_priv->int_tv_support = 1;
205 	dev_priv->int_crt_support = 1;
206 
207 	general = find_section(bdb, BDB_GENERAL_FEATURES);
208 	if (general) {
209 		dev_priv->int_tv_support = general->int_tv_support;
210 		dev_priv->int_crt_support = general->int_crt_support;
211 		dev_priv->lvds_use_ssc = general->enable_ssc;
212 
213 		if (dev_priv->lvds_use_ssc) {
214 			dev_priv->lvds_ssc_freq
215 				= general->ssc_freq ? 100 : 96;
216 		}
217 	}
218 }
219 
220 /**
221  * psb_intel_init_bios - initialize VBIOS settings & find VBT
222  * @dev: DRM device
223  *
224  * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
225  * to appropriate values.
226  *
227  * VBT existence is a sanity check that is relied on by other i830_bios.c code.
228  * Note that it would be better to use a BIOS call to get the VBT, as BIOSes may
229  * feed an updated VBT back through that, compared to what we'll fetch using
230  * this method of groping around in the BIOS data.
231  *
232  * Returns 0 on success, nonzero on failure.
233  */
234 bool psb_intel_init_bios(struct drm_device *dev)
235 {
236 	struct drm_psb_private *dev_priv = dev->dev_private;
237 	struct pci_dev *pdev = dev->pdev;
238 	struct vbt_header *vbt = NULL;
239 	struct bdb_header *bdb;
240 	u8 __iomem *bios;
241 	size_t size;
242 	int i;
243 
244 	bios = pci_map_rom(pdev, &size);
245 	if (!bios)
246 		return -1;
247 
248 	/* Scour memory looking for the VBT signature */
249 	for (i = 0; i + 4 < size; i++) {
250 		if (!memcmp(bios + i, "$VBT", 4)) {
251 			vbt = (struct vbt_header *)(bios + i);
252 			break;
253 		}
254 	}
255 
256 	if (!vbt) {
257 		dev_err(dev->dev, "VBT signature missing\n");
258 		pci_unmap_rom(pdev, bios);
259 		return -1;
260 	}
261 
262 	bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);
263 
264 	/* Grab useful general definitions */
265 	parse_general_features(dev_priv, bdb);
266 	parse_lfp_panel_data(dev_priv, bdb);
267 	parse_sdvo_panel_data(dev_priv, bdb);
268 	parse_backlight_data(dev_priv, bdb);
269 
270 	pci_unmap_rom(pdev, bios);
271 
272 	return 0;
273 }
274 
275 /**
276  * Destroy and free VBT data
277  */
278 void psb_intel_destroy_bios(struct drm_device *dev)
279 {
280 	struct drm_psb_private *dev_priv = dev->dev_private;
281 	struct drm_display_mode *sdvo_lvds_vbt_mode =
282 				dev_priv->sdvo_lvds_vbt_mode;
283 	struct drm_display_mode *lfp_lvds_vbt_mode =
284 				dev_priv->lfp_lvds_vbt_mode;
285 	struct bdb_lvds_backlight *lvds_bl =
286 				dev_priv->lvds_bl;
287 
288 	/*free sdvo panel mode*/
289 	if (sdvo_lvds_vbt_mode) {
290 		dev_priv->sdvo_lvds_vbt_mode = NULL;
291 		kfree(sdvo_lvds_vbt_mode);
292 	}
293 
294 	if (lfp_lvds_vbt_mode) {
295 		dev_priv->lfp_lvds_vbt_mode = NULL;
296 		kfree(lfp_lvds_vbt_mode);
297 	}
298 
299 	if (lvds_bl) {
300 		dev_priv->lvds_bl = NULL;
301 		kfree(lvds_bl);
302 	}
303 }
304