xref: /openbmc/u-boot/arch/arm/cpu/arm920t/imx/speed.c (revision c6af2e7d)
1 /*
2  *
3  * (c) 2004 Sascha Hauer <sascha@saschahauer.de>
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 
25 #include <common.h>
26 #if defined (CONFIG_IMX)
27 
28 #include <asm/arch/imx-regs.h>
29 
30 /* ------------------------------------------------------------------------- */
31 /* NOTE: This describes the proper use of this file.
32  *
33  * CONFIG_SYS_CLK_FREQ should be defined as the input frequency of the PLL.
34  * SH FIXME: 16780000 in our case
35  * get_FCLK(), get_HCLK(), get_PCLK() and get_UCLK() return the clock of
36  * the specified bus in HZ.
37  */
38 /* ------------------------------------------------------------------------- */
39 
40 ulong get_systemPLLCLK(void)
41 {
42 	/* FIXME: We assume System_SEL = 0 here */
43 	u32 spctl0 = SPCTL0;
44 	u32 mfi = (spctl0 >> 10) & 0xf;
45 	u32 mfn = spctl0 & 0x3f;
46 	u32 mfd = (spctl0 >> 16) & 0x3f;
47 	u32 pd =  (spctl0 >> 26) & 0xf;
48 
49 	mfi = mfi<=5 ? 5 : mfi;
50 
51 	return (2*(CONFIG_SYSPLL_CLK_FREQ>>10)*( (mfi<<10) + (mfn<<10)/(mfd+1)))/(pd+1);
52 }
53 
54 ulong get_mcuPLLCLK(void)
55 {
56 	/* FIXME: We assume System_SEL = 0 here */
57 	u32 mpctl0 = MPCTL0;
58 	u32 mfi = (mpctl0 >> 10) & 0xf;
59 	u32 mfn = mpctl0 & 0x3f;
60 	u32 mfd = (mpctl0 >> 16) & 0x3f;
61 	u32 pd =  (mpctl0 >> 26) & 0xf;
62 
63 	mfi = mfi<=5 ? 5 : mfi;
64 
65 	return (2*(CONFIG_SYS_CLK_FREQ>>10)*( (mfi<<10) + (mfn<<10)/(mfd+1)))/(pd+1);
66 }
67 
68 ulong get_FCLK(void)
69 {
70 	return (( CSCR>>15)&1) ? get_mcuPLLCLK()>>1 : get_mcuPLLCLK();
71 }
72 
73 /* return HCLK frequency */
74 ulong get_HCLK(void)
75 {
76 	u32 bclkdiv = (( CSCR >> 10 ) & 0xf) + 1;
77 	printf("bclkdiv: %d\n", bclkdiv);
78 	return get_systemPLLCLK() / bclkdiv;
79 }
80 
81 /* return BCLK frequency */
82 ulong get_BCLK(void)
83 {
84 	return get_HCLK();
85 }
86 
87 ulong get_PERCLK1(void)
88 {
89 	return get_systemPLLCLK() / (((PCDR) & 0xf)+1);
90 }
91 
92 ulong get_PERCLK2(void)
93 {
94 	return get_systemPLLCLK() / (((PCDR>>4) & 0xf)+1);
95 }
96 
97 ulong get_PERCLK3(void)
98 {
99 	return get_systemPLLCLK() / (((PCDR>>16) & 0x7f)+1);
100 }
101 
102 #endif /* defined (CONFIG_IMX) */
103