xref: /openbmc/u-boot/arch/arm/cpu/arm1136/mx31/generic.c (revision cd8c8775)
1 /*
2  * (C) Copyright 2007
3  * Sascha Hauer, Pengutronix
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 #include <common.h>
25 #include <asm/arch/imx-regs.h>
26 #include <asm/io.h>
27 
28 static u32 mx31_decode_pll(u32 reg, u32 infreq)
29 {
30 	u32 mfi = (reg >> 10) & 0xf;
31 	u32 mfn = reg & 0x3ff;
32 	u32 mfd = (reg >> 16) & 0x3ff;
33 	u32 pd =  (reg >> 26) & 0xf;
34 
35 	mfi = mfi <= 5 ? 5 : mfi;
36 	mfd += 1;
37 	pd += 1;
38 
39 	return ((2 * (infreq >> 10) * (mfi * mfd + mfn)) /
40 		(mfd * pd)) << 10;
41 }
42 
43 static u32 mx31_get_mpl_dpdgck_clk(void)
44 {
45 	u32 infreq;
46 
47 	if ((__REG(CCM_CCMR) & CCMR_PRCS_MASK) == CCMR_FPM)
48 		infreq = CONFIG_MX31_CLK32 * 1024;
49 	else
50 		infreq = CONFIG_MX31_HCLK_FREQ;
51 
52 	return mx31_decode_pll(__REG(CCM_MPCTL), infreq);
53 }
54 
55 static u32 mx31_get_mcu_main_clk(void)
56 {
57 	/* For now we assume mpl_dpdgck_clk == mcu_main_clk
58 	 * which should be correct for most boards
59 	 */
60 	return mx31_get_mpl_dpdgck_clk();
61 }
62 
63 u32 mx31_get_ipg_clk(void)
64 {
65 	u32 freq = mx31_get_mcu_main_clk();
66 	u32 pdr0 = __REG(CCM_PDR0);
67 
68 	freq /= ((pdr0 >> 3) & 0x7) + 1;
69 	freq /= ((pdr0 >> 6) & 0x3) + 1;
70 
71 	return freq;
72 }
73 
74 void mx31_dump_clocks(void)
75 {
76 	u32 cpufreq = mx31_get_mcu_main_clk();
77 	printf("mx31 cpu clock: %dMHz\n",cpufreq / 1000000);
78 	printf("ipg clock     : %dHz\n", mx31_get_ipg_clk());
79 }
80 
81 void mx31_gpio_mux(unsigned long mode)
82 {
83 	unsigned long reg, shift, tmp;
84 
85 	reg = IOMUXC_BASE + (mode & 0x1fc);
86 	shift = (~mode & 0x3) * 8;
87 
88 	tmp = __REG(reg);
89 	tmp &= ~(0xff << shift);
90 	tmp |= ((mode >> IOMUX_MODE_POS) & 0xff) << shift;
91 	__REG(reg) = tmp;
92 }
93 
94 void mx31_set_pad(enum iomux_pins pin, u32 config)
95 {
96 	u32 field, l, reg;
97 
98 	pin &= IOMUX_PADNUM_MASK;
99 	reg = (IOMUXC_BASE + 0x154) + (pin + 2) / 3 * 4;
100 	field = (pin + 2) % 3;
101 
102 	l = __REG(reg);
103 	l &= ~(0x1ff << (field * 10));
104 	l |= config << (field * 10);
105 	__REG(reg) = l;
106 
107 }
108 
109 struct mx3_cpu_type mx31_cpu_type[] = {
110 	{ .srev = 0x00, .v = 0x10 },
111 	{ .srev = 0x10, .v = 0x11 },
112 	{ .srev = 0x11, .v = 0x11 },
113 	{ .srev = 0x12, .v = 0x1F },
114 	{ .srev = 0x13, .v = 0x1F },
115 	{ .srev = 0x14, .v = 0x12 },
116 	{ .srev = 0x15, .v = 0x12 },
117 	{ .srev = 0x28, .v = 0x20 },
118 	{ .srev = 0x29, .v = 0x20 },
119 };
120 
121 u32 get_cpu_rev(void)
122 {
123 	u32 i, srev;
124 
125 	/* read SREV register from IIM module */
126 	struct iim_regs *iim = (struct iim_regs *)MX31_IIM_BASE_ADDR;
127 	srev = readl(&iim->iim_srev);
128 
129 	for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
130 		if (srev == mx31_cpu_type[i].srev)
131 			return mx31_cpu_type[i].v;
132 
133 	return srev | 0x8000;
134 }
135 
136 char *get_reset_cause(void)
137 {
138 	/* read RCSR register from CCM module */
139 	struct clock_control_regs *ccm =
140 		(struct clock_control_regs *)CCM_BASE;
141 
142 	u32 cause = readl(&ccm->rcsr) & 0x07;
143 
144 	switch (cause) {
145 	case 0x0000:
146 		return "POR";
147 		break;
148 	case 0x0001:
149 		return "RST";
150 		break;
151 	case 0x0002:
152 		return "WDOG";
153 		break;
154 	case 0x0006:
155 		return "JTAG";
156 		break;
157 	default:
158 		return "unknown reset";
159 	}
160 }
161 
162 #if defined(CONFIG_DISPLAY_CPUINFO)
163 int print_cpuinfo (void)
164 {
165 	u32 srev = get_cpu_rev();
166 
167 	printf("CPU:   Freescale i.MX31 rev %d.%d%s at %d MHz.",
168 			(srev & 0xF0) >> 4, (srev & 0x0F),
169 			((srev & 0x8000) ? " unknown" : ""),
170 			mx31_get_mcu_main_clk() / 1000000);
171 	printf("Reset cause: %s\n", get_reset_cause());
172 	return 0;
173 }
174 #endif
175