xref: /openbmc/u-boot/arch/arm/cpu/arm1136/mx31/generic.c (revision 7c2eabab)
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/arch/clock.h>
27 #include <asm/io.h>
28 
29 static u32 mx31_decode_pll(u32 reg, u32 infreq)
30 {
31 	u32 mfi = (reg >> 10) & 0xf;
32 	u32 mfn = reg & 0x3ff;
33 	u32 mfd = (reg >> 16) & 0x3ff;
34 	u32 pd =  (reg >> 26) & 0xf;
35 
36 	mfi = mfi <= 5 ? 5 : mfi;
37 	mfd += 1;
38 	pd += 1;
39 
40 	return ((2 * (infreq >> 10) * (mfi * mfd + mfn)) /
41 		(mfd * pd)) << 10;
42 }
43 
44 static u32 mx31_get_mpl_dpdgck_clk(void)
45 {
46 	u32 infreq;
47 
48 	if ((__REG(CCM_CCMR) & CCMR_PRCS_MASK) == CCMR_FPM)
49 		infreq = CONFIG_MX31_CLK32 * 1024;
50 	else
51 		infreq = CONFIG_MX31_HCLK_FREQ;
52 
53 	return mx31_decode_pll(__REG(CCM_MPCTL), infreq);
54 }
55 
56 static u32 mx31_get_mcu_main_clk(void)
57 {
58 	/* For now we assume mpl_dpdgck_clk == mcu_main_clk
59 	 * which should be correct for most boards
60 	 */
61 	return mx31_get_mpl_dpdgck_clk();
62 }
63 
64 static u32 mx31_get_ipg_clk(void)
65 {
66 	u32 freq = mx31_get_mcu_main_clk();
67 	u32 pdr0 = __REG(CCM_PDR0);
68 
69 	freq /= ((pdr0 >> 3) & 0x7) + 1;
70 	freq /= ((pdr0 >> 6) & 0x3) + 1;
71 
72 	return freq;
73 }
74 
75 void mx31_dump_clocks(void)
76 {
77 	u32 cpufreq = mx31_get_mcu_main_clk();
78 	printf("mx31 cpu clock: %dMHz\n",cpufreq / 1000000);
79 	printf("ipg clock     : %dHz\n", mx31_get_ipg_clk());
80 }
81 
82 unsigned int mxc_get_clock(enum mxc_clock clk)
83 {
84 	switch (clk) {
85 	case MXC_ARM_CLK:
86 		return mx31_get_mcu_main_clk();
87 	case MXC_IPG_CLK:
88 	case MXC_IPG_PERCLK:
89 	case MXC_CSPI_CLK:
90 	case MXC_UART_CLK:
91 		return mx31_get_ipg_clk();
92 	}
93 	return -1;
94 }
95 
96 u32 imx_get_uartclk(void)
97 {
98 	return mxc_get_clock(MXC_UART_CLK);
99 }
100 
101 void mx31_gpio_mux(unsigned long mode)
102 {
103 	unsigned long reg, shift, tmp;
104 
105 	reg = IOMUXC_BASE + (mode & 0x1fc);
106 	shift = (~mode & 0x3) * 8;
107 
108 	tmp = __REG(reg);
109 	tmp &= ~(0xff << shift);
110 	tmp |= ((mode >> IOMUX_MODE_POS) & 0xff) << shift;
111 	__REG(reg) = tmp;
112 }
113 
114 void mx31_set_pad(enum iomux_pins pin, u32 config)
115 {
116 	u32 field, l, reg;
117 
118 	pin &= IOMUX_PADNUM_MASK;
119 	reg = (IOMUXC_BASE + 0x154) + (pin + 2) / 3 * 4;
120 	field = (pin + 2) % 3;
121 
122 	l = __REG(reg);
123 	l &= ~(0x1ff << (field * 10));
124 	l |= config << (field * 10);
125 	__REG(reg) = l;
126 
127 }
128 
129 struct mx3_cpu_type mx31_cpu_type[] = {
130 	{ .srev = 0x00, .v = 0x10 },
131 	{ .srev = 0x10, .v = 0x11 },
132 	{ .srev = 0x11, .v = 0x11 },
133 	{ .srev = 0x12, .v = 0x1F },
134 	{ .srev = 0x13, .v = 0x1F },
135 	{ .srev = 0x14, .v = 0x12 },
136 	{ .srev = 0x15, .v = 0x12 },
137 	{ .srev = 0x28, .v = 0x20 },
138 	{ .srev = 0x29, .v = 0x20 },
139 };
140 
141 u32 get_cpu_rev(void)
142 {
143 	u32 i, srev;
144 
145 	/* read SREV register from IIM module */
146 	struct iim_regs *iim = (struct iim_regs *)MX31_IIM_BASE_ADDR;
147 	srev = readl(&iim->iim_srev);
148 
149 	for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
150 		if (srev == mx31_cpu_type[i].srev)
151 			return mx31_cpu_type[i].v;
152 
153 	return srev | 0x8000;
154 }
155 
156 static char *get_reset_cause(void)
157 {
158 	/* read RCSR register from CCM module */
159 	struct clock_control_regs *ccm =
160 		(struct clock_control_regs *)CCM_BASE;
161 
162 	u32 cause = readl(&ccm->rcsr) & 0x07;
163 
164 	switch (cause) {
165 	case 0x0000:
166 		return "POR";
167 	case 0x0001:
168 		return "RST";
169 	case 0x0002:
170 		return "WDOG";
171 	case 0x0006:
172 		return "JTAG";
173 	default:
174 		return "unknown reset";
175 	}
176 }
177 
178 #if defined(CONFIG_DISPLAY_CPUINFO)
179 int print_cpuinfo (void)
180 {
181 	u32 srev = get_cpu_rev();
182 
183 	printf("CPU:   Freescale i.MX31 rev %d.%d%s at %d MHz.\n",
184 			(srev & 0xF0) >> 4, (srev & 0x0F),
185 			((srev & 0x8000) ? " unknown" : ""),
186 			mx31_get_mcu_main_clk() / 1000000);
187 	printf("Reset cause: %s\n", get_reset_cause());
188 	return 0;
189 }
190 #endif
191