1 /*
2  * Geode GX display controller.
3  *
4  *   Copyright (C) 2005 Arcom Control Systems Ltd.
5  *
6  *   Portions from AMD's original 2.4 driver:
7  *     Copyright (C) 2004 Advanced Micro Devices, Inc.
8  *
9  *   This program is free software; you can redistribute it and/or modify it
10  *   under the terms of the GNU General Public License as published by * the
11  *   Free Software Foundation; either version 2 of the License, or * (at your
12  *   option) any later version.
13  */
14 #include <linux/spinlock.h>
15 #include <linux/fb.h>
16 #include <linux/delay.h>
17 #include <asm/io.h>
18 #include <asm/div64.h>
19 #include <asm/delay.h>
20 #include <linux/cs5535.h>
21 
22 #include "gxfb.h"
23 
24 unsigned int gx_frame_buffer_size(void)
25 {
26 	unsigned int val;
27 
28 	if (!cs5535_has_vsa2()) {
29 		uint32_t hi, lo;
30 
31 		/* The number of pages is (PMAX - PMIN)+1 */
32 		rdmsr(MSR_GLIU_P2D_RO0, lo, hi);
33 
34 		/* PMAX */
35 		val = ((hi & 0xff) << 12) | ((lo & 0xfff00000) >> 20);
36 		/* PMIN */
37 		val -= (lo & 0x000fffff);
38 		val += 1;
39 
40 		/* The page size is 4k */
41 		return (val << 12);
42 	}
43 
44 	/* FB size can be obtained from the VSA II */
45 	/* Virtual register class = 0x02 */
46 	/* VG_MEM_SIZE(512Kb units) = 0x00 */
47 
48 	outw(VSA_VR_UNLOCK, VSA_VRC_INDEX);
49 	outw(VSA_VR_MEM_SIZE, VSA_VRC_INDEX);
50 
51 	val = (unsigned int)(inw(VSA_VRC_DATA)) & 0xFFl;
52 	return (val << 19);
53 }
54 
55 int gx_line_delta(int xres, int bpp)
56 {
57 	/* Must be a multiple of 8 bytes. */
58 	return (xres * (bpp >> 3) + 7) & ~0x7;
59 }
60 
61 void gx_set_mode(struct fb_info *info)
62 {
63 	struct gxfb_par *par = info->par;
64 	u32 gcfg, dcfg;
65 	int hactive, hblankstart, hsyncstart, hsyncend, hblankend, htotal;
66 	int vactive, vblankstart, vsyncstart, vsyncend, vblankend, vtotal;
67 
68 	/* Unlock the display controller registers. */
69 	write_dc(par, DC_UNLOCK, DC_UNLOCK_UNLOCK);
70 
71 	gcfg = read_dc(par, DC_GENERAL_CFG);
72 	dcfg = read_dc(par, DC_DISPLAY_CFG);
73 
74 	/* Disable the timing generator. */
75 	dcfg &= ~DC_DISPLAY_CFG_TGEN;
76 	write_dc(par, DC_DISPLAY_CFG, dcfg);
77 
78 	/* Wait for pending memory requests before disabling the FIFO load. */
79 	udelay(100);
80 
81 	/* Disable FIFO load and compression. */
82 	gcfg &= ~(DC_GENERAL_CFG_DFLE | DC_GENERAL_CFG_CMPE |
83 			DC_GENERAL_CFG_DECE);
84 	write_dc(par, DC_GENERAL_CFG, gcfg);
85 
86 	/* Setup DCLK and its divisor. */
87 	gx_set_dclk_frequency(info);
88 
89 	/*
90 	 * Setup new mode.
91 	 */
92 
93 	/* Clear all unused feature bits. */
94 	gcfg &= DC_GENERAL_CFG_YUVM | DC_GENERAL_CFG_VDSE;
95 	dcfg = 0;
96 
97 	/* Set FIFO priority (default 6/5) and enable. */
98 	/* FIXME: increase fifo priority for 1280x1024 and higher modes? */
99 	gcfg |= (6 << DC_GENERAL_CFG_DFHPEL_SHIFT) |
100 		(5 << DC_GENERAL_CFG_DFHPSL_SHIFT) | DC_GENERAL_CFG_DFLE;
101 
102 	/* Framebuffer start offset. */
103 	write_dc(par, DC_FB_ST_OFFSET, 0);
104 
105 	/* Line delta and line buffer length. */
106 	write_dc(par, DC_GFX_PITCH, info->fix.line_length >> 3);
107 	write_dc(par, DC_LINE_SIZE,
108 		((info->var.xres * info->var.bits_per_pixel/8) >> 3) + 2);
109 
110 
111 	/* Enable graphics and video data and unmask address lines. */
112 	dcfg |= DC_DISPLAY_CFG_GDEN | DC_DISPLAY_CFG_VDEN |
113 		DC_DISPLAY_CFG_A20M | DC_DISPLAY_CFG_A18M;
114 
115 	/* Set pixel format. */
116 	switch (info->var.bits_per_pixel) {
117 	case 8:
118 		dcfg |= DC_DISPLAY_CFG_DISP_MODE_8BPP;
119 		break;
120 	case 16:
121 		dcfg |= DC_DISPLAY_CFG_DISP_MODE_16BPP;
122 		break;
123 	case 32:
124 		dcfg |= DC_DISPLAY_CFG_DISP_MODE_24BPP;
125 		dcfg |= DC_DISPLAY_CFG_PALB;
126 		break;
127 	}
128 
129 	/* Enable timing generator. */
130 	dcfg |= DC_DISPLAY_CFG_TGEN;
131 
132 	/* Horizontal and vertical timings. */
133 	hactive = info->var.xres;
134 	hblankstart = hactive;
135 	hsyncstart = hblankstart + info->var.right_margin;
136 	hsyncend =  hsyncstart + info->var.hsync_len;
137 	hblankend = hsyncend + info->var.left_margin;
138 	htotal = hblankend;
139 
140 	vactive = info->var.yres;
141 	vblankstart = vactive;
142 	vsyncstart = vblankstart + info->var.lower_margin;
143 	vsyncend =  vsyncstart + info->var.vsync_len;
144 	vblankend = vsyncend + info->var.upper_margin;
145 	vtotal = vblankend;
146 
147 	write_dc(par, DC_H_ACTIVE_TIMING, (hactive - 1)    |
148 			((htotal - 1) << 16));
149 	write_dc(par, DC_H_BLANK_TIMING, (hblankstart - 1) |
150 			((hblankend - 1) << 16));
151 	write_dc(par, DC_H_SYNC_TIMING, (hsyncstart - 1)   |
152 			((hsyncend - 1) << 16));
153 
154 	write_dc(par, DC_V_ACTIVE_TIMING, (vactive - 1)    |
155 			((vtotal - 1) << 16));
156 	write_dc(par, DC_V_BLANK_TIMING, (vblankstart - 1) |
157 			((vblankend - 1) << 16));
158 	write_dc(par, DC_V_SYNC_TIMING, (vsyncstart - 1)   |
159 			((vsyncend - 1) << 16));
160 
161 	/* Write final register values. */
162 	write_dc(par, DC_DISPLAY_CFG, dcfg);
163 	write_dc(par, DC_GENERAL_CFG, gcfg);
164 
165 	gx_configure_display(info);
166 
167 	/* Relock display controller registers */
168 	write_dc(par, DC_UNLOCK, DC_UNLOCK_LOCK);
169 }
170 
171 void gx_set_hw_palette_reg(struct fb_info *info, unsigned regno,
172 		unsigned red, unsigned green, unsigned blue)
173 {
174 	struct gxfb_par *par = info->par;
175 	int val;
176 
177 	/* Hardware palette is in RGB 8-8-8 format. */
178 	val  = (red   << 8) & 0xff0000;
179 	val |= (green)      & 0x00ff00;
180 	val |= (blue  >> 8) & 0x0000ff;
181 
182 	write_dc(par, DC_PAL_ADDRESS, regno);
183 	write_dc(par, DC_PAL_DATA, val);
184 }
185