xref: /openbmc/u-boot/board/gdsys/p1022/diu.c (revision 3ebd892f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2010-2011 Freescale Semiconductor, Inc.
4  * Authors: Timur Tabi <timur@freescale.com>
5  *
6  * FSL DIU Framebuffer driver
7  */
8 
9 #include <common.h>
10 #include <command.h>
11 #include <linux/ctype.h>
12 #include <asm/io.h>
13 #include <stdio_dev.h>
14 #include <video_fb.h>
15 #include <fsl_diu_fb.h>
16 
17 #define PMUXCR_ELBCDIU_MASK	0xc0000000
18 #define PMUXCR_ELBCDIU_NOR16	0x80000000
19 #define PMUXCR_ELBCDIU_DIU	0x40000000
20 
21 /*
22  * DIU Area Descriptor
23  *
24  * Note that we need to byte-swap the value before it's written to the AD
25  * register.  So even though the registers don't look like they're in the same
26  * bit positions as they are on the MPC8610, the same value is written to the
27  * AD register on the MPC8610 and on the P1022.
28  */
29 #define AD_BYTE_F		0x10000000
30 #define AD_ALPHA_C_SHIFT	25
31 #define AD_BLUE_C_SHIFT		23
32 #define AD_GREEN_C_SHIFT	21
33 #define AD_RED_C_SHIFT		19
34 #define AD_PIXEL_S_SHIFT	16
35 #define AD_COMP_3_SHIFT		12
36 #define AD_COMP_2_SHIFT		8
37 #define AD_COMP_1_SHIFT		4
38 #define AD_COMP_0_SHIFT		0
39 
40 /*
41  * Variables used by the DIU/LBC switching code.  It's safe to makes these
42  * global, because the DIU requires DDR, so we'll only run this code after
43  * relocation.
44  */
45 static u32 pmuxcr;
46 
47 void diu_set_pixel_clock(unsigned int pixclock)
48 {
49 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
50 	unsigned long speed_ccb, temp;
51 	u32 pixval;
52 
53 	speed_ccb = get_bus_freq(0);
54 	temp = 1000000000 / pixclock;
55 	temp *= 1000;
56 	pixval = speed_ccb / temp;
57 	debug("DIU pixval = %u\n", pixval);
58 
59 	/* Modify PXCLK in GUTS CLKDVDR */
60 	temp = in_be32(&gur->clkdvdr) & 0x2000FFFF;
61 	out_be32(&gur->clkdvdr, temp);			/* turn off clock */
62 	out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
63 }
64 
65 int platform_diu_init(unsigned int xres, unsigned int yres, const char *port)
66 {
67 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
68 	u32 pixel_format;
69 
70 	pixel_format = cpu_to_le32(AD_BYTE_F | (3 << AD_ALPHA_C_SHIFT) |
71 		(0 << AD_BLUE_C_SHIFT) | (1 << AD_GREEN_C_SHIFT) |
72 		(2 << AD_RED_C_SHIFT) | (8 << AD_COMP_3_SHIFT) |
73 		(8 << AD_COMP_2_SHIFT) | (8 << AD_COMP_1_SHIFT) |
74 		(8 << AD_COMP_0_SHIFT) | (3 << AD_PIXEL_S_SHIFT));
75 
76 	printf("DIU:   Switching to %ux%u\n", xres, yres);
77 
78 	/* Set PMUXCR to switch the muxed pins from the LBC to the DIU */
79 	clrsetbits_be32(&gur->pmuxcr, PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_DIU);
80 	pmuxcr = in_be32(&gur->pmuxcr);
81 
82 	return fsl_diu_init(xres, yres, pixel_format, 0);
83 }
84