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gerrit.cesnet.cz / github / trini / u-boot / 5f4c3137f4f051787707c548133823f1656eb508 / . / cpu / arm1176 / s3c64xx / speed.c
blob: 5c335a55a9e9b02780656cd927c0b56b78655bd3 [file] [log] [blame]
Guennadi Liakhovetski9b077732008-08-31 00:39:46 +0200[diff] [blame]1/*
2 * (C) Copyright 2001-2004
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 *
5 * (C) Copyright 2002
6 * David Mueller, ELSOFT AG, d.mueller@elsoft.ch
7 *
8 * See file CREDITS for list of people who contributed to this
9 * project.
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation; either version 2 of
14 * the License, or (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24 * MA 02111-1307 USA
25 */
26
27/*
28 * This code should work for both the S3C2400 and the S3C2410
29 * as they seem to have the same PLL and clock machinery inside.
30 * The different address mapping is handled by the s3c24xx.h files below.
31 */
32
33#include <common.h>
34#include <s3c6400.h>
35
36#define APLL 0
37#define MPLL 1
38#define EPLL 2
39
40/* ------------------------------------------------------------------------- */
41/*
42 * NOTE: This describes the proper use of this file.
43 *
44 * CONFIG_SYS_CLK_FREQ should be defined as the input frequency of the PLL.
45 *
46 * get_FCLK(), get_HCLK(), get_PCLK() and get_UCLK() return the clock of
47 * the specified bus in HZ.
48 */
49/* ------------------------------------------------------------------------- */
50
51static ulong get_PLLCLK(int pllreg)
52{
53 ulong r, m, p, s;
54
55 switch (pllreg) {
56 case APLL:
57 r = APLL_CON_REG;
58 break;
59 case MPLL:
60 r = MPLL_CON_REG;
61 break;
62 case EPLL:
63 r = EPLL_CON0_REG;
64 break;
65 default:
66 hang();
67 }
68
69 m = (r >> 16) & 0x3ff;
70 p = (r >> 8) & 0x3f;
71 s = r & 0x7;
72
73 return m * (CONFIG_SYS_CLK_FREQ / (p * (1 << s)));
74}
75
76/* return ARMCORE frequency */
77ulong get_ARMCLK(void)
78{
79 ulong div;
80
81 div = CLK_DIV0_REG;
82
83 return get_PLLCLK(APLL) / ((div & 0x7) + 1);
84}
85
86/* return FCLK frequency */
87ulong get_FCLK(void)
88{
89 return get_PLLCLK(APLL);
90}
91
92/* return HCLK frequency */
93ulong get_HCLK(void)
94{
95 ulong fclk;
96
97 uint hclkx2_div = ((CLK_DIV0_REG >> 9) & 0x7) + 1;
98 uint hclk_div = ((CLK_DIV0_REG >> 8) & 0x1) + 1;
99
100 /*
101 * Bit 7 exists on s3c6410, and not on s3c6400, it is reserved on
102 * s3c6400 and is always 0, and it is indeed running in ASYNC mode
103 */
104 if (OTHERS_REG & 0x80)
105 fclk = get_FCLK(); /* SYNC Mode */
106 else
107 fclk = get_PLLCLK(MPLL); /* ASYNC Mode */
108
109 return fclk / (hclk_div * hclkx2_div);
110}
111
112/* return PCLK frequency */
113ulong get_PCLK(void)
114{
115 ulong fclk;
116 uint hclkx2_div = ((CLK_DIV0_REG >> 9) & 0x7) + 1;
117 uint pre_div = ((CLK_DIV0_REG >> 12) & 0xf) + 1;
118
119 if (OTHERS_REG & 0x80)
120 fclk = get_FCLK(); /* SYNC Mode */
121 else
122 fclk = get_PLLCLK(MPLL); /* ASYNC Mode */
123
124 return fclk / (hclkx2_div * pre_div);
125}
126
127/* return UCLK frequency */
128ulong get_UCLK(void)
129{
130 return get_PLLCLK(EPLL);
131}
132
133int print_cpuinfo(void)
134{
135 printf("\nCPU: S3C6400@%luMHz\n", get_ARMCLK() / 1000000);
136 printf(" Fclk = %luMHz, Hclk = %luMHz, Pclk = %luMHz ",
137 get_FCLK() / 1000000, get_HCLK() / 1000000,
138 get_PCLK() / 1000000);
139
140 if (OTHERS_REG & 0x80)
141 printf("(SYNC Mode) \n");
142 else
143 printf("(ASYNC Mode) \n");
144 return 0;
145}