xref: /openbmc/u-boot/arch/arm/cpu/arm1136/mx31/generic.c (revision 2482e3c8)
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 = GET_PLL_MFI(reg);
32 	u32 mfn = GET_PLL_MFN(reg);
33 	u32 mfd = GET_PLL_MFD(reg);
34 	u32 pd =  GET_PLL_PD(reg);
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 ((readl(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(readl(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 = readl(CCM_PDR0);
68 
69 	freq /= GET_PDR0_MAX_PODF(pdr0) + 1;
70 	freq /= GET_PDR0_IPG_PODF(pdr0) + 1;
71 
72 	return freq;
73 }
74 
75 /* hsp is the clock for the ipu */
76 static u32 mx31_get_hsp_clk(void)
77 {
78 	u32 freq = mx31_get_mcu_main_clk();
79 	u32 pdr0 = readl(CCM_PDR0);
80 
81 	freq /= GET_PDR0_HSP_PODF(pdr0) + 1;
82 
83 	return freq;
84 }
85 
86 void mx31_dump_clocks(void)
87 {
88 	u32 cpufreq = mx31_get_mcu_main_clk();
89 	printf("mx31 cpu clock: %dMHz\n",cpufreq / 1000000);
90 	printf("ipg clock     : %dHz\n", mx31_get_ipg_clk());
91 	printf("hsp clock     : %dHz\n", mx31_get_hsp_clk());
92 }
93 
94 unsigned int mxc_get_clock(enum mxc_clock clk)
95 {
96 	switch (clk) {
97 	case MXC_ARM_CLK:
98 		return mx31_get_mcu_main_clk();
99 	case MXC_IPG_CLK:
100 	case MXC_IPG_PERCLK:
101 	case MXC_CSPI_CLK:
102 	case MXC_UART_CLK:
103 		return mx31_get_ipg_clk();
104 	case MXC_IPU_CLK:
105 		return mx31_get_hsp_clk();
106 	}
107 	return -1;
108 }
109 
110 u32 imx_get_uartclk(void)
111 {
112 	return mxc_get_clock(MXC_UART_CLK);
113 }
114 
115 void mx31_gpio_mux(unsigned long mode)
116 {
117 	unsigned long reg, shift, tmp;
118 
119 	reg = IOMUXC_BASE + (mode & 0x1fc);
120 	shift = (~mode & 0x3) * 8;
121 
122 	tmp = readl(reg);
123 	tmp &= ~(0xff << shift);
124 	tmp |= ((mode >> IOMUX_MODE_POS) & 0xff) << shift;
125 	writel(tmp, reg);
126 }
127 
128 void mx31_set_pad(enum iomux_pins pin, u32 config)
129 {
130 	u32 field, l, reg;
131 
132 	pin &= IOMUX_PADNUM_MASK;
133 	reg = (IOMUXC_BASE + 0x154) + (pin + 2) / 3 * 4;
134 	field = (pin + 2) % 3;
135 
136 	l = readl(reg);
137 	l &= ~(0x1ff << (field * 10));
138 	l |= config << (field * 10);
139 	writel(l, reg);
140 
141 }
142 
143 struct mx3_cpu_type mx31_cpu_type[] = {
144 	{ .srev = 0x00, .v = 0x10 },
145 	{ .srev = 0x10, .v = 0x11 },
146 	{ .srev = 0x11, .v = 0x11 },
147 	{ .srev = 0x12, .v = 0x1F },
148 	{ .srev = 0x13, .v = 0x1F },
149 	{ .srev = 0x14, .v = 0x12 },
150 	{ .srev = 0x15, .v = 0x12 },
151 	{ .srev = 0x28, .v = 0x20 },
152 	{ .srev = 0x29, .v = 0x20 },
153 };
154 
155 u32 get_cpu_rev(void)
156 {
157 	u32 i, srev;
158 
159 	/* read SREV register from IIM module */
160 	struct iim_regs *iim = (struct iim_regs *)MX31_IIM_BASE_ADDR;
161 	srev = readl(&iim->iim_srev);
162 
163 	for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
164 		if (srev == mx31_cpu_type[i].srev)
165 			return mx31_cpu_type[i].v;
166 
167 	return srev | 0x8000;
168 }
169 
170 static char *get_reset_cause(void)
171 {
172 	/* read RCSR register from CCM module */
173 	struct clock_control_regs *ccm =
174 		(struct clock_control_regs *)CCM_BASE;
175 
176 	u32 cause = readl(&ccm->rcsr) & 0x07;
177 
178 	switch (cause) {
179 	case 0x0000:
180 		return "POR";
181 	case 0x0001:
182 		return "RST";
183 	case 0x0002:
184 		return "WDOG";
185 	case 0x0006:
186 		return "JTAG";
187 	default:
188 		return "unknown reset";
189 	}
190 }
191 
192 #if defined(CONFIG_DISPLAY_CPUINFO)
193 int print_cpuinfo (void)
194 {
195 	u32 srev = get_cpu_rev();
196 
197 	printf("CPU:   Freescale i.MX31 rev %d.%d%s at %d MHz.\n",
198 			(srev & 0xF0) >> 4, (srev & 0x0F),
199 			((srev & 0x8000) ? " unknown" : ""),
200 			mx31_get_mcu_main_clk() / 1000000);
201 	printf("Reset cause: %s\n", get_reset_cause());
202 	return 0;
203 }
204 #endif
205