xref: /openbmc/u-boot/board/gdsys/p1022/diu.c (revision fd697ecf)
1 /*
2  * Copyright 2010-2011 Freescale Semiconductor, Inc.
3  * Authors: Timur Tabi <timur@freescale.com>
4  *
5  * FSL DIU Framebuffer driver
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; either version 2 of the License, or (at your option)
10  * any later version.
11  */
12 
13 #include <common.h>
14 #include <command.h>
15 #include <linux/ctype.h>
16 #include <asm/io.h>
17 #include <stdio_dev.h>
18 #include <video_fb.h>
19 #include <fsl_diu_fb.h>
20 
21 #define PMUXCR_ELBCDIU_MASK	0xc0000000
22 #define PMUXCR_ELBCDIU_NOR16	0x80000000
23 #define PMUXCR_ELBCDIU_DIU	0x40000000
24 
25 /*
26  * DIU Area Descriptor
27  *
28  * Note that we need to byte-swap the value before it's written to the AD
29  * register.  So even though the registers don't look like they're in the same
30  * bit positions as they are on the MPC8610, the same value is written to the
31  * AD register on the MPC8610 and on the P1022.
32  */
33 #define AD_BYTE_F		0x10000000
34 #define AD_ALPHA_C_SHIFT	25
35 #define AD_BLUE_C_SHIFT		23
36 #define AD_GREEN_C_SHIFT	21
37 #define AD_RED_C_SHIFT		19
38 #define AD_PIXEL_S_SHIFT	16
39 #define AD_COMP_3_SHIFT		12
40 #define AD_COMP_2_SHIFT		8
41 #define AD_COMP_1_SHIFT		4
42 #define AD_COMP_0_SHIFT		0
43 
44 /*
45  * Variables used by the DIU/LBC switching code.  It's safe to makes these
46  * global, because the DIU requires DDR, so we'll only run this code after
47  * relocation.
48  */
49 static u32 pmuxcr;
50 
51 void diu_set_pixel_clock(unsigned int pixclock)
52 {
53 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
54 	unsigned long speed_ccb, temp;
55 	u32 pixval;
56 
57 	speed_ccb = get_bus_freq(0);
58 	temp = 1000000000 / pixclock;
59 	temp *= 1000;
60 	pixval = speed_ccb / temp;
61 	debug("DIU pixval = %u\n", pixval);
62 
63 	/* Modify PXCLK in GUTS CLKDVDR */
64 	temp = in_be32(&gur->clkdvdr) & 0x2000FFFF;
65 	out_be32(&gur->clkdvdr, temp);			/* turn off clock */
66 	out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
67 }
68 
69 int platform_diu_init(unsigned int xres, unsigned int yres, const char *port)
70 {
71 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
72 	u32 pixel_format;
73 
74 	pixel_format = cpu_to_le32(AD_BYTE_F | (3 << AD_ALPHA_C_SHIFT) |
75 		(0 << AD_BLUE_C_SHIFT) | (1 << AD_GREEN_C_SHIFT) |
76 		(2 << AD_RED_C_SHIFT) | (8 << AD_COMP_3_SHIFT) |
77 		(8 << AD_COMP_2_SHIFT) | (8 << AD_COMP_1_SHIFT) |
78 		(8 << AD_COMP_0_SHIFT) | (3 << AD_PIXEL_S_SHIFT));
79 
80 	printf("DIU:   Switching to %ux%u\n", xres, yres);
81 
82 	/* Set PMUXCR to switch the muxed pins from the LBC to the DIU */
83 	clrsetbits_be32(&gur->pmuxcr, PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_DIU);
84 	pmuxcr = in_be32(&gur->pmuxcr);
85 
86 	return fsl_diu_init(xres, yres, pixel_format, 0);
87 }
88