1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers/video/geode/video_cs5530.c
4  *   -- CS5530 video device
5  *
6  * Copyright (C) 2005 Arcom Control Systems Ltd.
7  *
8  * Based on AMD's original 2.4 driver:
9  *   Copyright (C) 2004 Advanced Micro Devices, Inc.
10  */
11 #include <linux/fb.h>
12 #include <linux/delay.h>
13 #include <asm/io.h>
14 #include <asm/delay.h>
15 
16 #include "geodefb.h"
17 #include "video_cs5530.h"
18 
19 /*
20  * CS5530 PLL table. This maps pixclocks to the appropriate PLL register
21  * value.
22  */
23 struct cs5530_pll_entry {
24 	long pixclock; /* ps */
25 	u32 pll_value;
26 };
27 
28 static const struct cs5530_pll_entry cs5530_pll_table[] = {
29 	{ 39721, 0x31C45801, }, /*  25.1750 MHz */
30 	{ 35308, 0x20E36802, }, /*  28.3220 */
31 	{ 31746, 0x33915801, }, /*  31.5000 */
32 	{ 27777, 0x31EC4801, }, /*  36.0000 */
33 	{ 26666, 0x21E22801, }, /*  37.5000 */
34 	{ 25000, 0x33088801, }, /*  40.0000 */
35 	{ 22271, 0x33E22801, }, /*  44.9000 */
36 	{ 20202, 0x336C4801, }, /*  49.5000 */
37 	{ 20000, 0x23088801, }, /*  50.0000 */
38 	{ 19860, 0x23088801, }, /*  50.3500 */
39 	{ 18518, 0x3708A801, }, /*  54.0000 */
40 	{ 17777, 0x23E36802, }, /*  56.2500 */
41 	{ 17733, 0x23E36802, }, /*  56.3916 */
42 	{ 17653, 0x23E36802, }, /*  56.6444 */
43 	{ 16949, 0x37C45801, }, /*  59.0000 */
44 	{ 15873, 0x23EC4801, }, /*  63.0000 */
45 	{ 15384, 0x37911801, }, /*  65.0000 */
46 	{ 14814, 0x37963803, }, /*  67.5000 */
47 	{ 14124, 0x37058803, }, /*  70.8000 */
48 	{ 13888, 0x3710C805, }, /*  72.0000 */
49 	{ 13333, 0x37E22801, }, /*  75.0000 */
50 	{ 12698, 0x27915801, }, /*  78.7500 */
51 	{ 12500, 0x37D8D802, }, /*  80.0000 */
52 	{ 11135, 0x27588802, }, /*  89.8000 */
53 	{ 10582, 0x27EC4802, }, /*  94.5000 */
54 	{ 10101, 0x27AC6803, }, /*  99.0000 */
55 	{ 10000, 0x27088801, }, /* 100.0000 */
56 	{  9259, 0x2710C805, }, /* 108.0000 */
57 	{  8888, 0x27E36802, }, /* 112.5000 */
58 	{  7692, 0x27C58803, }, /* 130.0000 */
59 	{  7407, 0x27316803, }, /* 135.0000 */
60 	{  6349, 0x2F915801, }, /* 157.5000 */
61 	{  6172, 0x2F08A801, }, /* 162.0000 */
62 	{  5714, 0x2FB11802, }, /* 175.0000 */
63 	{  5291, 0x2FEC4802, }, /* 189.0000 */
64 	{  4950, 0x2F963803, }, /* 202.0000 */
65 	{  4310, 0x2FB1B802, }, /* 232.0000 */
66 };
67 
68 static void cs5530_set_dclk_frequency(struct fb_info *info)
69 {
70 	struct geodefb_par *par = info->par;
71 	int i;
72 	u32 value;
73 	long min, diff;
74 
75 	/* Search the table for the closest pixclock. */
76 	value = cs5530_pll_table[0].pll_value;
77 	min = cs5530_pll_table[0].pixclock - info->var.pixclock;
78 	if (min < 0) min = -min;
79 	for (i = 1; i < ARRAY_SIZE(cs5530_pll_table); i++) {
80 		diff = cs5530_pll_table[i].pixclock - info->var.pixclock;
81 		if (diff < 0L) diff = -diff;
82 		if (diff < min) {
83 			min = diff;
84 			value = cs5530_pll_table[i].pll_value;
85 		}
86 	}
87 
88 	writel(value, par->vid_regs + CS5530_DOT_CLK_CONFIG);
89 	writel(value | 0x80000100, par->vid_regs + CS5530_DOT_CLK_CONFIG); /* set reset and bypass */
90 	udelay(500); /* wait for PLL to settle */
91 	writel(value & 0x7FFFFFFF, par->vid_regs + CS5530_DOT_CLK_CONFIG); /* clear reset */
92 	writel(value & 0x7FFFFEFF, par->vid_regs + CS5530_DOT_CLK_CONFIG); /* clear bypass */
93 }
94 
95 static void cs5530_configure_display(struct fb_info *info)
96 {
97 	struct geodefb_par *par = info->par;
98 	u32 dcfg;
99 
100 	dcfg = readl(par->vid_regs + CS5530_DISPLAY_CONFIG);
101 
102 	/* Clear bits from existing mode. */
103 	dcfg &= ~(CS5530_DCFG_CRT_SYNC_SKW_MASK | CS5530_DCFG_PWR_SEQ_DLY_MASK
104 		  | CS5530_DCFG_CRT_HSYNC_POL   | CS5530_DCFG_CRT_VSYNC_POL
105 		  | CS5530_DCFG_FP_PWR_EN       | CS5530_DCFG_FP_DATA_EN
106 		  | CS5530_DCFG_DAC_PWR_EN      | CS5530_DCFG_VSYNC_EN
107 		  | CS5530_DCFG_HSYNC_EN);
108 
109 	/* Set default sync skew and power sequence delays.  */
110 	dcfg |= (CS5530_DCFG_CRT_SYNC_SKW_INIT | CS5530_DCFG_PWR_SEQ_DLY_INIT
111 		 | CS5530_DCFG_GV_PAL_BYP);
112 
113 	/* Enable DACs, hsync and vsync for CRTs */
114 	if (par->enable_crt) {
115 		dcfg |= CS5530_DCFG_DAC_PWR_EN;
116 		dcfg |= CS5530_DCFG_HSYNC_EN | CS5530_DCFG_VSYNC_EN;
117 	}
118 	/* Enable panel power and data if using a flat panel. */
119 	if (par->panel_x > 0) {
120 		dcfg |= CS5530_DCFG_FP_PWR_EN;
121 		dcfg |= CS5530_DCFG_FP_DATA_EN;
122 	}
123 
124 	/* Sync polarities. */
125 	if (info->var.sync & FB_SYNC_HOR_HIGH_ACT)
126 		dcfg |= CS5530_DCFG_CRT_HSYNC_POL;
127 	if (info->var.sync & FB_SYNC_VERT_HIGH_ACT)
128 		dcfg |= CS5530_DCFG_CRT_VSYNC_POL;
129 
130 	writel(dcfg, par->vid_regs + CS5530_DISPLAY_CONFIG);
131 }
132 
133 static int cs5530_blank_display(struct fb_info *info, int blank_mode)
134 {
135 	struct geodefb_par *par = info->par;
136 	u32 dcfg;
137 	int blank, hsync, vsync;
138 
139 	switch (blank_mode) {
140 	case FB_BLANK_UNBLANK:
141 		blank = 0; hsync = 1; vsync = 1;
142 		break;
143 	case FB_BLANK_NORMAL:
144 		blank = 1; hsync = 1; vsync = 1;
145 		break;
146 	case FB_BLANK_VSYNC_SUSPEND:
147 		blank = 1; hsync = 1; vsync = 0;
148 		break;
149 	case FB_BLANK_HSYNC_SUSPEND:
150 		blank = 1; hsync = 0; vsync = 1;
151 		break;
152 	case FB_BLANK_POWERDOWN:
153 		blank = 1; hsync = 0; vsync = 0;
154 		break;
155 	default:
156 		return -EINVAL;
157 	}
158 
159 	dcfg = readl(par->vid_regs + CS5530_DISPLAY_CONFIG);
160 
161 	dcfg &= ~(CS5530_DCFG_DAC_BL_EN | CS5530_DCFG_DAC_PWR_EN
162 		  | CS5530_DCFG_HSYNC_EN | CS5530_DCFG_VSYNC_EN
163 		  | CS5530_DCFG_FP_DATA_EN | CS5530_DCFG_FP_PWR_EN);
164 
165 	if (par->enable_crt) {
166 		if (!blank)
167 			dcfg |= CS5530_DCFG_DAC_BL_EN | CS5530_DCFG_DAC_PWR_EN;
168 		if (hsync)
169 			dcfg |= CS5530_DCFG_HSYNC_EN;
170 		if (vsync)
171 			dcfg |= CS5530_DCFG_VSYNC_EN;
172 	}
173 	if (par->panel_x > 0) {
174 		if (!blank)
175 			dcfg |= CS5530_DCFG_FP_DATA_EN;
176 		if (hsync && vsync)
177 			dcfg |= CS5530_DCFG_FP_PWR_EN;
178 	}
179 
180 	writel(dcfg, par->vid_regs + CS5530_DISPLAY_CONFIG);
181 
182 	return 0;
183 }
184 
185 const struct geode_vid_ops cs5530_vid_ops = {
186 	.set_dclk          = cs5530_set_dclk_frequency,
187 	.configure_display = cs5530_configure_display,
188 	.blank_display     = cs5530_blank_display,
189 };
190