1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2004 Freescale Semiconductor.
4  * Jeff Brown
5  * Srikanth Srinivasan (srikanth.srinivasan@freescale.com)
6  *
7  * (C) Copyright 2000-2002
8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
9  */
10 
11 #include <common.h>
12 #include <clock_legacy.h>
13 #include <mpc86xx.h>
14 #include <asm/global_data.h>
15 #include <asm/processor.h>
16 #include <asm/io.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 /* used in some defintiions of CONFIG_SYS_CLK_FREQ */
21 extern unsigned long get_board_sys_clk(unsigned long dummy);
22 
get_sys_info(sys_info_t * sys_info)23 void get_sys_info(sys_info_t *sys_info)
24 {
25 	volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
26 	volatile ccsr_gur_t *gur = &immap->im_gur;
27 	uint plat_ratio, e600_ratio;
28 
29 	plat_ratio = (gur->porpllsr) & 0x0000003e;
30 	plat_ratio >>= 1;
31 
32 	switch (plat_ratio) {
33 	case 0x0:
34 		sys_info->freq_systembus = 16 * CONFIG_SYS_CLK_FREQ;
35 		break;
36 	case 0x02:
37 	case 0x03:
38 	case 0x04:
39 	case 0x05:
40 	case 0x06:
41 	case 0x08:
42 	case 0x09:
43 	case 0x0a:
44 	case 0x0c:
45 	case 0x10:
46 		sys_info->freq_systembus = plat_ratio * CONFIG_SYS_CLK_FREQ;
47 		break;
48 	default:
49 		sys_info->freq_systembus = 0;
50 		break;
51 	}
52 
53 	e600_ratio = (gur->porpllsr) & 0x003f0000;
54 	e600_ratio >>= 16;
55 
56 	switch (e600_ratio) {
57 	case 0x10:
58 		sys_info->freq_processor = 2 * sys_info->freq_systembus;
59 		break;
60 	case 0x19:
61 		sys_info->freq_processor = 5 * sys_info->freq_systembus / 2;
62 		break;
63 	case 0x20:
64 		sys_info->freq_processor = 3 * sys_info->freq_systembus;
65 		break;
66 	case 0x39:
67 		sys_info->freq_processor = 7 * sys_info->freq_systembus / 2;
68 		break;
69 	case 0x28:
70 		sys_info->freq_processor = 4 * sys_info->freq_systembus;
71 		break;
72 	case 0x1d:
73 		sys_info->freq_processor = 9 * sys_info->freq_systembus / 2;
74 		break;
75 	default:
76 		sys_info->freq_processor = e600_ratio +
77 						sys_info->freq_systembus;
78 		break;
79 	}
80 
81 	sys_info->freq_localbus = sys_info->freq_systembus;
82 }
83 
84 
85 /*
86  * Measure CPU clock speed (core clock GCLK1, GCLK2)
87  * (Approx. GCLK frequency in Hz)
88  */
89 
get_clocks(void)90 int get_clocks(void)
91 {
92 	sys_info_t sys_info;
93 
94 	get_sys_info(&sys_info);
95 	gd->cpu_clk = sys_info.freq_processor;
96 	gd->bus_clk = sys_info.freq_systembus;
97 	gd->arch.lbc_clk = sys_info.freq_localbus;
98 
99 	/*
100 	 * The base clock for I2C depends on the actual SOC.  Unfortunately,
101 	 * there is no pattern that can be used to determine the frequency, so
102 	 * the only choice is to look up the actual SOC number and use the value
103 	 * for that SOC. This information is taken from application note
104 	 * AN2919.
105 	 */
106 #ifdef CONFIG_ARCH_MPC8610
107 	gd->arch.i2c1_clk = sys_info.freq_systembus;
108 #else
109 	gd->arch.i2c1_clk = sys_info.freq_systembus / 2;
110 #endif
111 	gd->arch.i2c2_clk = gd->arch.i2c1_clk;
112 
113 	if (gd->cpu_clk != 0)
114 		return 0;
115 	else
116 		return 1;
117 }
118 
119 
120 /*
121  * get_bus_freq
122  *	Return system bus freq in Hz
123  */
124 
get_bus_freq(ulong dummy)125 ulong get_bus_freq(ulong dummy)
126 {
127 	ulong val;
128 	sys_info_t sys_info;
129 
130 	get_sys_info(&sys_info);
131 	val = sys_info.freq_systembus;
132 
133 	return val;
134 }
135