1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * drivers/video/geode/display_gx1.c
4 *   -- Geode GX1 display controller
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/spinlock.h>
12#include <linux/fb.h>
13#include <linux/delay.h>
14#include <asm/io.h>
15#include <asm/div64.h>
16#include <asm/delay.h>
17
18#include "geodefb.h"
19#include "display_gx1.h"
20
21static DEFINE_SPINLOCK(gx1_conf_reg_lock);
22
23static u8 gx1_read_conf_reg(u8 reg)
24{
25	u8 val, ccr3;
26	unsigned long flags;
27
28	spin_lock_irqsave(&gx1_conf_reg_lock, flags);
29
30	outb(CONFIG_CCR3, 0x22);
31	ccr3 = inb(0x23);
32	outb(CONFIG_CCR3, 0x22);
33	outb(ccr3 | CONFIG_CCR3_MAPEN, 0x23);
34	outb(reg, 0x22);
35	val = inb(0x23);
36	outb(CONFIG_CCR3, 0x22);
37	outb(ccr3, 0x23);
38
39	spin_unlock_irqrestore(&gx1_conf_reg_lock, flags);
40
41	return val;
42}
43
44unsigned gx1_gx_base(void)
45{
46	return (gx1_read_conf_reg(CONFIG_GCR) & 0x03) << 30;
47}
48
49int gx1_frame_buffer_size(void)
50{
51	void __iomem *mc_regs;
52	u32 bank_cfg;
53	int d;
54	unsigned dram_size = 0, fb_base;
55
56	mc_regs = ioremap(gx1_gx_base() + 0x8400, 0x100);
57	if (!mc_regs)
58		return -ENOMEM;
59
60
61	/* Calculate the total size of both DIMM0 and DIMM1. */
62	bank_cfg = readl(mc_regs + MC_BANK_CFG);
63
64	for (d = 0; d < 2; d++) {
65		if ((bank_cfg & MC_BCFG_DIMM0_PG_SZ_MASK) != MC_BCFG_DIMM0_PG_SZ_NO_DIMM)
66			dram_size += 0x400000 << ((bank_cfg & MC_BCFG_DIMM0_SZ_MASK) >> 8);
67		bank_cfg >>= 16; /* look at DIMM1 next */
68	}
69
70	fb_base = (readl(mc_regs + MC_GBASE_ADD) & MC_GADD_GBADD_MASK) << 19;
71
72	iounmap(mc_regs);
73
74	return dram_size - fb_base;
75}
76
77static void gx1_set_mode(struct fb_info *info)
78{
79	struct geodefb_par *par = info->par;
80	u32 gcfg, tcfg, ocfg, dclk_div, val;
81	int hactive, hblankstart, hsyncstart, hsyncend, hblankend, htotal;
82	int vactive, vblankstart, vsyncstart, vsyncend, vblankend, vtotal;
83
84	/* Unlock the display controller registers. */
85	readl(par->dc_regs + DC_UNLOCK);
86	writel(DC_UNLOCK_CODE, par->dc_regs + DC_UNLOCK);
87
88	gcfg = readl(par->dc_regs + DC_GENERAL_CFG);
89	tcfg = readl(par->dc_regs + DC_TIMING_CFG);
90
91	/* Blank the display and disable the timing generator. */
92	tcfg &= ~(DC_TCFG_BLKE | DC_TCFG_TGEN);
93	writel(tcfg, par->dc_regs + DC_TIMING_CFG);
94
95	/* Wait for pending memory requests before disabling the FIFO load. */
96	udelay(100);
97
98	/* Disable FIFO load and compression. */
99	gcfg &= ~(DC_GCFG_DFLE | DC_GCFG_CMPE | DC_GCFG_DECE);
100	writel(gcfg, par->dc_regs + DC_GENERAL_CFG);
101
102	/* Setup DCLK and its divisor. */
103	gcfg &= ~DC_GCFG_DCLK_MASK;
104	writel(gcfg, par->dc_regs + DC_GENERAL_CFG);
105
106	par->vid_ops->set_dclk(info);
107
108	dclk_div = DC_GCFG_DCLK_DIV_1; /* FIXME: may need to divide DCLK by 2 sometimes? */
109	gcfg |= dclk_div;
110	writel(gcfg, par->dc_regs + DC_GENERAL_CFG);
111
112	/* Wait for the clock generatation to settle.  This is needed since
113	 * some of the register writes that follow require that clock to be
114	 * present. */
115	udelay(1000); /* FIXME: seems a little long */
116
117	/*
118	 * Setup new mode.
119	 */
120
121	/* Clear all unused feature bits. */
122	gcfg = DC_GCFG_VRDY | dclk_div;
123
124	/* Set FIFO priority (default 6/5) and enable. */
125	/* FIXME: increase fifo priority for 1280x1024 modes? */
126	gcfg |= (6 << DC_GCFG_DFHPEL_POS) | (5 << DC_GCFG_DFHPSL_POS) | DC_GCFG_DFLE;
127
128	/* FIXME: Set pixel and line double bits if necessary. */
129
130	/* Framebuffer start offset. */
131	writel(0, par->dc_regs + DC_FB_ST_OFFSET);
132
133	/* Line delta and line buffer length. */
134	writel(info->fix.line_length >> 2, par->dc_regs + DC_LINE_DELTA);
135	writel(((info->var.xres * info->var.bits_per_pixel/8) >> 3) + 2,
136	       par->dc_regs + DC_BUF_SIZE);
137
138	/* Output configuration. Enable panel data, set pixel format. */
139	ocfg = DC_OCFG_PCKE | DC_OCFG_PDEL | DC_OCFG_PDEH;
140	if (info->var.bits_per_pixel == 8) ocfg |= DC_OCFG_8BPP;
141
142	/* Enable timing generator, sync and FP data. */
143	tcfg = DC_TCFG_FPPE | DC_TCFG_HSYE | DC_TCFG_VSYE | DC_TCFG_BLKE
144		| DC_TCFG_TGEN;
145
146	/* Horizontal and vertical timings. */
147	hactive = info->var.xres;
148	hblankstart = hactive;
149	hsyncstart = hblankstart + info->var.right_margin;
150	hsyncend =  hsyncstart + info->var.hsync_len;
151	hblankend = hsyncend + info->var.left_margin;
152	htotal = hblankend;
153
154	vactive = info->var.yres;
155	vblankstart = vactive;
156	vsyncstart = vblankstart + info->var.lower_margin;
157	vsyncend =  vsyncstart + info->var.vsync_len;
158	vblankend = vsyncend + info->var.upper_margin;
159	vtotal = vblankend;
160
161	val = (hactive - 1) | ((htotal - 1) << 16);
162	writel(val, par->dc_regs + DC_H_TIMING_1);
163	val = (hblankstart - 1) | ((hblankend - 1) << 16);
164	writel(val, par->dc_regs + DC_H_TIMING_2);
165	val = (hsyncstart - 1) | ((hsyncend - 1) << 16);
166	writel(val, par->dc_regs + DC_H_TIMING_3);
167	writel(val, par->dc_regs + DC_FP_H_TIMING);
168	val = (vactive - 1) | ((vtotal - 1) << 16);
169	writel(val, par->dc_regs + DC_V_TIMING_1);
170	val = (vblankstart - 1) | ((vblankend - 1) << 16);
171	writel(val, par->dc_regs + DC_V_TIMING_2);
172	val = (vsyncstart - 1) | ((vsyncend - 1) << 16);
173	writel(val, par->dc_regs + DC_V_TIMING_3);
174	val = (vsyncstart - 2) | ((vsyncend - 2) << 16);
175	writel(val, par->dc_regs + DC_FP_V_TIMING);
176
177	/* Write final register values. */
178	writel(ocfg, par->dc_regs + DC_OUTPUT_CFG);
179	writel(tcfg, par->dc_regs + DC_TIMING_CFG);
180	udelay(1000); /* delay after TIMING_CFG. FIXME: perhaps a little long */
181	writel(gcfg, par->dc_regs + DC_GENERAL_CFG);
182
183	par->vid_ops->configure_display(info);
184
185	/* Relock display controller registers */
186	writel(0, par->dc_regs + DC_UNLOCK);
187
188	/* FIXME: write line_length and bpp to Graphics Pipeline GP_BLT_STATUS
189	 * register. */
190}
191
192static void gx1_set_hw_palette_reg(struct fb_info *info, unsigned regno,
193				   unsigned red, unsigned green, unsigned blue)
194{
195	struct geodefb_par *par = info->par;
196	int val;
197
198	/* Hardware palette is in RGB 6-6-6 format. */
199	val  = (red   <<  2) & 0x3f000;
200	val |= (green >>  4) & 0x00fc0;
201	val |= (blue  >> 10) & 0x0003f;
202
203	writel(regno, par->dc_regs + DC_PAL_ADDRESS);
204	writel(val, par->dc_regs + DC_PAL_DATA);
205}
206
207const struct geode_dc_ops gx1_dc_ops = {
208	.set_mode	 = gx1_set_mode,
209	.set_palette_reg = gx1_set_hw_palette_reg,
210};
211