xref: /linux/drivers/video/fbdev/geode/video_gx.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Geode GX video processor device.
4  *
5  *   Copyright (C) 2006 Arcom Control Systems Ltd.
6  *
7  *   Portions from AMD's original 2.4 driver:
8  *     Copyright (C) 2004 Advanced Micro Devices, Inc.
9  */
10 #include <linux/fb.h>
11 #include <linux/delay.h>
12 #include <asm/io.h>
13 #include <asm/delay.h>
14 #include <asm/msr.h>
15 #include <linux/cs5535.h>
16 
17 #include "gxfb.h"
18 
19 
20 /*
21  * Tables of register settings for various DOTCLKs.
22  */
23 struct gx_pll_entry {
24 	long pixclock; /* ps */
25 	u32 sys_rstpll_bits;
26 	u32 dotpll_value;
27 };
28 
29 #define POSTDIV3 ((u32)MSR_GLCP_SYS_RSTPLL_DOTPOSTDIV3)
30 #define PREMULT2 ((u32)MSR_GLCP_SYS_RSTPLL_DOTPREMULT2)
31 #define PREDIV2  ((u32)MSR_GLCP_SYS_RSTPLL_DOTPOSTDIV3)
32 
33 static const struct gx_pll_entry gx_pll_table_48MHz[] = {
34 	{ 40123, POSTDIV3,	    0x00000BF2 },	/*  24.9230 */
35 	{ 39721, 0,		    0x00000037 },	/*  25.1750 */
36 	{ 35308, POSTDIV3|PREMULT2, 0x00000B1A },	/*  28.3220 */
37 	{ 31746, POSTDIV3,	    0x000002D2 },	/*  31.5000 */
38 	{ 27777, POSTDIV3|PREMULT2, 0x00000FE2 },	/*  36.0000 */
39 	{ 26666, POSTDIV3,	    0x0000057A },	/*  37.5000 */
40 	{ 25000, POSTDIV3,	    0x0000030A },	/*  40.0000 */
41 	{ 22271, 0,		    0x00000063 },	/*  44.9000 */
42 	{ 20202, 0,		    0x0000054B },	/*  49.5000 */
43 	{ 20000, 0,		    0x0000026E },	/*  50.0000 */
44 	{ 19860, PREMULT2,	    0x00000037 },	/*  50.3500 */
45 	{ 18518, POSTDIV3|PREMULT2, 0x00000B0D },	/*  54.0000 */
46 	{ 17777, 0,		    0x00000577 },	/*  56.2500 */
47 	{ 17733, 0,		    0x000007F7 },	/*  56.3916 */
48 	{ 17653, 0,		    0x0000057B },	/*  56.6444 */
49 	{ 16949, PREMULT2,	    0x00000707 },	/*  59.0000 */
50 	{ 15873, POSTDIV3|PREMULT2, 0x00000B39 },	/*  63.0000 */
51 	{ 15384, POSTDIV3|PREMULT2, 0x00000B45 },	/*  65.0000 */
52 	{ 14814, POSTDIV3|PREMULT2, 0x00000FC1 },	/*  67.5000 */
53 	{ 14124, POSTDIV3,	    0x00000561 },	/*  70.8000 */
54 	{ 13888, POSTDIV3,	    0x000007E1 },	/*  72.0000 */
55 	{ 13426, PREMULT2,	    0x00000F4A },	/*  74.4810 */
56 	{ 13333, 0,		    0x00000052 },	/*  75.0000 */
57 	{ 12698, 0,		    0x00000056 },	/*  78.7500 */
58 	{ 12500, POSTDIV3|PREMULT2, 0x00000709 },	/*  80.0000 */
59 	{ 11135, PREMULT2,	    0x00000262 },	/*  89.8000 */
60 	{ 10582, 0,		    0x000002D2 },	/*  94.5000 */
61 	{ 10101, PREMULT2,	    0x00000B4A },	/*  99.0000 */
62 	{ 10000, PREMULT2,	    0x00000036 },	/* 100.0000 */
63 	{  9259, 0,		    0x000007E2 },	/* 108.0000 */
64 	{  8888, 0,		    0x000007F6 },	/* 112.5000 */
65 	{  7692, POSTDIV3|PREMULT2, 0x00000FB0 },	/* 130.0000 */
66 	{  7407, POSTDIV3|PREMULT2, 0x00000B50 },	/* 135.0000 */
67 	{  6349, 0,		    0x00000055 },	/* 157.5000 */
68 	{  6172, 0,		    0x000009C1 },	/* 162.0000 */
69 	{  5787, PREMULT2,	    0x0000002D },	/* 172.798  */
70 	{  5698, 0,		    0x000002C1 },	/* 175.5000 */
71 	{  5291, 0,		    0x000002D1 },	/* 189.0000 */
72 	{  4938, 0,		    0x00000551 },	/* 202.5000 */
73 	{  4357, 0,		    0x0000057D },	/* 229.5000 */
74 };
75 
76 static const struct gx_pll_entry gx_pll_table_14MHz[] = {
77 	{ 39721, 0, 0x00000037 },	/*  25.1750 */
78 	{ 35308, 0, 0x00000B7B },	/*  28.3220 */
79 	{ 31746, 0, 0x000004D3 },	/*  31.5000 */
80 	{ 27777, 0, 0x00000BE3 },	/*  36.0000 */
81 	{ 26666, 0, 0x0000074F },	/*  37.5000 */
82 	{ 25000, 0, 0x0000050B },	/*  40.0000 */
83 	{ 22271, 0, 0x00000063 },	/*  44.9000 */
84 	{ 20202, 0, 0x0000054B },	/*  49.5000 */
85 	{ 20000, 0, 0x0000026E },	/*  50.0000 */
86 	{ 19860, 0, 0x000007C3 },	/*  50.3500 */
87 	{ 18518, 0, 0x000007E3 },	/*  54.0000 */
88 	{ 17777, 0, 0x00000577 },	/*  56.2500 */
89 	{ 17733, 0, 0x000002FB },	/*  56.3916 */
90 	{ 17653, 0, 0x0000057B },	/*  56.6444 */
91 	{ 16949, 0, 0x0000058B },	/*  59.0000 */
92 	{ 15873, 0, 0x0000095E },	/*  63.0000 */
93 	{ 15384, 0, 0x0000096A },	/*  65.0000 */
94 	{ 14814, 0, 0x00000BC2 },	/*  67.5000 */
95 	{ 14124, 0, 0x0000098A },	/*  70.8000 */
96 	{ 13888, 0, 0x00000BE2 },	/*  72.0000 */
97 	{ 13333, 0, 0x00000052 },	/*  75.0000 */
98 	{ 12698, 0, 0x00000056 },	/*  78.7500 */
99 	{ 12500, 0, 0x0000050A },	/*  80.0000 */
100 	{ 11135, 0, 0x0000078E },	/*  89.8000 */
101 	{ 10582, 0, 0x000002D2 },	/*  94.5000 */
102 	{ 10101, 0, 0x000011F6 },	/*  99.0000 */
103 	{ 10000, 0, 0x0000054E },	/* 100.0000 */
104 	{  9259, 0, 0x000007E2 },	/* 108.0000 */
105 	{  8888, 0, 0x000002FA },	/* 112.5000 */
106 	{  7692, 0, 0x00000BB1 },	/* 130.0000 */
107 	{  7407, 0, 0x00000975 },	/* 135.0000 */
108 	{  6349, 0, 0x00000055 },	/* 157.5000 */
109 	{  6172, 0, 0x000009C1 },	/* 162.0000 */
110 	{  5698, 0, 0x000002C1 },	/* 175.5000 */
111 	{  5291, 0, 0x00000539 },	/* 189.0000 */
112 	{  4938, 0, 0x00000551 },	/* 202.5000 */
113 	{  4357, 0, 0x0000057D },	/* 229.5000 */
114 };
115 
116 void gx_set_dclk_frequency(struct fb_info *info)
117 {
118 	const struct gx_pll_entry *pll_table;
119 	int pll_table_len;
120 	int i, best_i;
121 	long min, diff;
122 	u64 dotpll, sys_rstpll;
123 	int timeout = 1000;
124 
125 	/* Rev. 1 Geode GXs use a 14 MHz reference clock instead of 48 MHz. */
126 	if (cpu_data(0).x86_stepping == 1) {
127 		pll_table = gx_pll_table_14MHz;
128 		pll_table_len = ARRAY_SIZE(gx_pll_table_14MHz);
129 	} else {
130 		pll_table = gx_pll_table_48MHz;
131 		pll_table_len = ARRAY_SIZE(gx_pll_table_48MHz);
132 	}
133 
134 	/* Search the table for the closest pixclock. */
135 	best_i = 0;
136 	min = abs(pll_table[0].pixclock - info->var.pixclock);
137 	for (i = 1; i < pll_table_len; i++) {
138 		diff = abs(pll_table[i].pixclock - info->var.pixclock);
139 		if (diff < min) {
140 			min = diff;
141 			best_i = i;
142 		}
143 	}
144 
145 	rdmsrl(MSR_GLCP_SYS_RSTPLL, sys_rstpll);
146 	rdmsrl(MSR_GLCP_DOTPLL, dotpll);
147 
148 	/* Program new M, N and P. */
149 	dotpll &= 0x00000000ffffffffull;
150 	dotpll |= (u64)pll_table[best_i].dotpll_value << 32;
151 	dotpll |= MSR_GLCP_DOTPLL_DOTRESET;
152 	dotpll &= ~MSR_GLCP_DOTPLL_BYPASS;
153 
154 	wrmsrl(MSR_GLCP_DOTPLL, dotpll);
155 
156 	/* Program dividers. */
157 	sys_rstpll &= ~( MSR_GLCP_SYS_RSTPLL_DOTPREDIV2
158 			 | MSR_GLCP_SYS_RSTPLL_DOTPREMULT2
159 			 | MSR_GLCP_SYS_RSTPLL_DOTPOSTDIV3 );
160 	sys_rstpll |= pll_table[best_i].sys_rstpll_bits;
161 
162 	wrmsrl(MSR_GLCP_SYS_RSTPLL, sys_rstpll);
163 
164 	/* Clear reset bit to start PLL. */
165 	dotpll &= ~(MSR_GLCP_DOTPLL_DOTRESET);
166 	wrmsrl(MSR_GLCP_DOTPLL, dotpll);
167 
168 	/* Wait for LOCK bit. */
169 	do {
170 		rdmsrl(MSR_GLCP_DOTPLL, dotpll);
171 	} while (timeout-- && !(dotpll & MSR_GLCP_DOTPLL_LOCK));
172 }
173 
174 static void
175 gx_configure_tft(struct fb_info *info)
176 {
177 	struct gxfb_par *par = info->par;
178 	unsigned long val;
179 	unsigned long fp;
180 
181 	/* Set up the DF pad select MSR */
182 
183 	rdmsrl(MSR_GX_MSR_PADSEL, val);
184 	val &= ~MSR_GX_MSR_PADSEL_MASK;
185 	val |= MSR_GX_MSR_PADSEL_TFT;
186 	wrmsrl(MSR_GX_MSR_PADSEL, val);
187 
188 	/* Turn off the panel */
189 
190 	fp = read_fp(par, FP_PM);
191 	fp &= ~FP_PM_P;
192 	write_fp(par, FP_PM, fp);
193 
194 	/* Set timing 1 */
195 
196 	fp = read_fp(par, FP_PT1);
197 	fp &= FP_PT1_VSIZE_MASK;
198 	fp |= info->var.yres << FP_PT1_VSIZE_SHIFT;
199 	write_fp(par, FP_PT1, fp);
200 
201 	/* Timing 2 */
202 	/* Set bits that are always on for TFT */
203 
204 	fp = 0x0F100000;
205 
206 	/* Configure sync polarity */
207 
208 	if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
209 		fp |= FP_PT2_VSP;
210 
211 	if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
212 		fp |= FP_PT2_HSP;
213 
214 	write_fp(par, FP_PT2, fp);
215 
216 	/*  Set the dither control */
217 	write_fp(par, FP_DFC, FP_DFC_NFI);
218 
219 	/* Enable the FP data and power (in case the BIOS didn't) */
220 
221 	fp = read_vp(par, VP_DCFG);
222 	fp |= VP_DCFG_FP_PWR_EN | VP_DCFG_FP_DATA_EN;
223 	write_vp(par, VP_DCFG, fp);
224 
225 	/* Unblank the panel */
226 
227 	fp = read_fp(par, FP_PM);
228 	fp |= FP_PM_P;
229 	write_fp(par, FP_PM, fp);
230 }
231 
232 void gx_configure_display(struct fb_info *info)
233 {
234 	struct gxfb_par *par = info->par;
235 	u32 dcfg, misc;
236 
237 	/* Write the display configuration */
238 	dcfg = read_vp(par, VP_DCFG);
239 
240 	/* Disable hsync and vsync */
241 	dcfg &= ~(VP_DCFG_VSYNC_EN | VP_DCFG_HSYNC_EN);
242 	write_vp(par, VP_DCFG, dcfg);
243 
244 	/* Clear bits from existing mode. */
245 	dcfg &= ~(VP_DCFG_CRT_SYNC_SKW
246 		  | VP_DCFG_CRT_HSYNC_POL   | VP_DCFG_CRT_VSYNC_POL
247 		  | VP_DCFG_VSYNC_EN        | VP_DCFG_HSYNC_EN);
248 
249 	/* Set default sync skew.  */
250 	dcfg |= VP_DCFG_CRT_SYNC_SKW_DEFAULT;
251 
252 	/* Enable hsync and vsync. */
253 	dcfg |= VP_DCFG_HSYNC_EN | VP_DCFG_VSYNC_EN;
254 
255 	misc = read_vp(par, VP_MISC);
256 
257 	/* Disable gamma correction */
258 	misc |= VP_MISC_GAM_EN;
259 
260 	if (par->enable_crt) {
261 
262 		/* Power up the CRT DACs */
263 		misc &= ~(VP_MISC_APWRDN | VP_MISC_DACPWRDN);
264 		write_vp(par, VP_MISC, misc);
265 
266 		/* Only change the sync polarities if we are running
267 		 * in CRT mode.  The FP polarities will be handled in
268 		 * gxfb_configure_tft */
269 		if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
270 			dcfg |= VP_DCFG_CRT_HSYNC_POL;
271 		if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
272 			dcfg |= VP_DCFG_CRT_VSYNC_POL;
273 	} else {
274 		/* Power down the CRT DACs if in FP mode */
275 		misc |= (VP_MISC_APWRDN | VP_MISC_DACPWRDN);
276 		write_vp(par, VP_MISC, misc);
277 	}
278 
279 	/* Enable the display logic */
280 	/* Set up the DACS to blank normally */
281 
282 	dcfg |= VP_DCFG_CRT_EN | VP_DCFG_DAC_BL_EN;
283 
284 	/* Enable the external DAC VREF? */
285 
286 	write_vp(par, VP_DCFG, dcfg);
287 
288 	/* Set up the flat panel (if it is enabled) */
289 
290 	if (par->enable_crt == 0)
291 		gx_configure_tft(info);
292 }
293 
294 int gx_blank_display(struct fb_info *info, int blank_mode)
295 {
296 	struct gxfb_par *par = info->par;
297 	u32 dcfg, fp_pm;
298 	int blank, hsync, vsync, crt;
299 
300 	/* CRT power saving modes. */
301 	switch (blank_mode) {
302 	case FB_BLANK_UNBLANK:
303 		blank = 0; hsync = 1; vsync = 1; crt = 1;
304 		break;
305 	case FB_BLANK_NORMAL:
306 		blank = 1; hsync = 1; vsync = 1; crt = 1;
307 		break;
308 	case FB_BLANK_VSYNC_SUSPEND:
309 		blank = 1; hsync = 1; vsync = 0; crt = 1;
310 		break;
311 	case FB_BLANK_HSYNC_SUSPEND:
312 		blank = 1; hsync = 0; vsync = 1; crt = 1;
313 		break;
314 	case FB_BLANK_POWERDOWN:
315 		blank = 1; hsync = 0; vsync = 0; crt = 0;
316 		break;
317 	default:
318 		return -EINVAL;
319 	}
320 	dcfg = read_vp(par, VP_DCFG);
321 	dcfg &= ~(VP_DCFG_DAC_BL_EN | VP_DCFG_HSYNC_EN | VP_DCFG_VSYNC_EN |
322 			VP_DCFG_CRT_EN);
323 	if (!blank)
324 		dcfg |= VP_DCFG_DAC_BL_EN;
325 	if (hsync)
326 		dcfg |= VP_DCFG_HSYNC_EN;
327 	if (vsync)
328 		dcfg |= VP_DCFG_VSYNC_EN;
329 	if (crt)
330 		dcfg |= VP_DCFG_CRT_EN;
331 	write_vp(par, VP_DCFG, dcfg);
332 
333 	/* Power on/off flat panel. */
334 
335 	if (par->enable_crt == 0) {
336 		fp_pm = read_fp(par, FP_PM);
337 		if (blank_mode == FB_BLANK_POWERDOWN)
338 			fp_pm &= ~FP_PM_P;
339 		else
340 			fp_pm |= FP_PM_P;
341 		write_fp(par, FP_PM, fp_pm);
342 	}
343 
344 	return 0;
345 }
346