xref: /openbmc/u-boot/board/gdsys/p1022/diu.c (revision cf0bcd7d)
1 /*
2  * Copyright 2010-2011 Freescale Semiconductor, Inc.
3  * Authors: Timur Tabi <timur@freescale.com>
4  *
5  * FSL DIU Framebuffer driver
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <command.h>
12 #include <linux/ctype.h>
13 #include <asm/io.h>
14 #include <stdio_dev.h>
15 #include <video_fb.h>
16 #include <fsl_diu_fb.h>
17 
18 #define PMUXCR_ELBCDIU_MASK	0xc0000000
19 #define PMUXCR_ELBCDIU_NOR16	0x80000000
20 #define PMUXCR_ELBCDIU_DIU	0x40000000
21 
22 /*
23  * DIU Area Descriptor
24  *
25  * Note that we need to byte-swap the value before it's written to the AD
26  * register.  So even though the registers don't look like they're in the same
27  * bit positions as they are on the MPC8610, the same value is written to the
28  * AD register on the MPC8610 and on the P1022.
29  */
30 #define AD_BYTE_F		0x10000000
31 #define AD_ALPHA_C_SHIFT	25
32 #define AD_BLUE_C_SHIFT		23
33 #define AD_GREEN_C_SHIFT	21
34 #define AD_RED_C_SHIFT		19
35 #define AD_PIXEL_S_SHIFT	16
36 #define AD_COMP_3_SHIFT		12
37 #define AD_COMP_2_SHIFT		8
38 #define AD_COMP_1_SHIFT		4
39 #define AD_COMP_0_SHIFT		0
40 
41 /*
42  * Variables used by the DIU/LBC switching code.  It's safe to makes these
43  * global, because the DIU requires DDR, so we'll only run this code after
44  * relocation.
45  */
46 static u32 pmuxcr;
47 
48 void diu_set_pixel_clock(unsigned int pixclock)
49 {
50 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
51 	unsigned long speed_ccb, temp;
52 	u32 pixval;
53 
54 	speed_ccb = get_bus_freq(0);
55 	temp = 1000000000 / pixclock;
56 	temp *= 1000;
57 	pixval = speed_ccb / temp;
58 	debug("DIU pixval = %u\n", pixval);
59 
60 	/* Modify PXCLK in GUTS CLKDVDR */
61 	temp = in_be32(&gur->clkdvdr) & 0x2000FFFF;
62 	out_be32(&gur->clkdvdr, temp);			/* turn off clock */
63 	out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
64 }
65 
66 int platform_diu_init(unsigned int xres, unsigned int yres, const char *port)
67 {
68 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
69 	u32 pixel_format;
70 
71 	pixel_format = cpu_to_le32(AD_BYTE_F | (3 << AD_ALPHA_C_SHIFT) |
72 		(0 << AD_BLUE_C_SHIFT) | (1 << AD_GREEN_C_SHIFT) |
73 		(2 << AD_RED_C_SHIFT) | (8 << AD_COMP_3_SHIFT) |
74 		(8 << AD_COMP_2_SHIFT) | (8 << AD_COMP_1_SHIFT) |
75 		(8 << AD_COMP_0_SHIFT) | (3 << AD_PIXEL_S_SHIFT));
76 
77 	printf("DIU:   Switching to %ux%u\n", xres, yres);
78 
79 	/* Set PMUXCR to switch the muxed pins from the LBC to the DIU */
80 	clrsetbits_be32(&gur->pmuxcr, PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_DIU);
81 	pmuxcr = in_be32(&gur->pmuxcr);
82 
83 	return fsl_diu_init(xres, yres, pixel_format, 0);
84 }
85