xref: /openbmc/u-boot/arch/arm/cpu/arm1136/mx31/generic.c (revision 4e43b2e8)
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/mx31-regs.h>
26 
27 static u32 mx31_decode_pll(u32 reg, u32 infreq)
28 {
29 	u32 mfi = (reg >> 10) & 0xf;
30 	u32 mfn = reg & 0x3ff;
31 	u32 mfd = (reg >> 16) & 0x3ff;
32 	u32 pd =  (reg >> 26) & 0xf;
33 
34 	mfi = mfi <= 5 ? 5 : mfi;
35 	mfd += 1;
36 	pd += 1;
37 
38 	return ((2 * (infreq >> 10) * (mfi * mfd + mfn)) /
39 		(mfd * pd)) << 10;
40 }
41 
42 static u32 mx31_get_mpl_dpdgck_clk(void)
43 {
44 	u32 infreq;
45 
46 	if ((__REG(CCM_CCMR) & CCMR_PRCS_MASK) == CCMR_FPM)
47 		infreq = CONFIG_MX31_CLK32 * 1024;
48 	else
49 		infreq = CONFIG_MX31_HCLK_FREQ;
50 
51 	return mx31_decode_pll(__REG(CCM_MPCTL), infreq);
52 }
53 
54 static u32 mx31_get_mcu_main_clk(void)
55 {
56 	/* For now we assume mpl_dpdgck_clk == mcu_main_clk
57 	 * which should be correct for most boards
58 	 */
59 	return mx31_get_mpl_dpdgck_clk();
60 }
61 
62 u32 mx31_get_ipg_clk(void)
63 {
64 	u32 freq = mx31_get_mcu_main_clk();
65 	u32 pdr0 = __REG(CCM_PDR0);
66 
67 	freq /= ((pdr0 >> 3) & 0x7) + 1;
68 	freq /= ((pdr0 >> 6) & 0x3) + 1;
69 
70 	return freq;
71 }
72 
73 void mx31_dump_clocks(void)
74 {
75 	u32 cpufreq = mx31_get_mcu_main_clk();
76 	printf("mx31 cpu clock: %dMHz\n",cpufreq / 1000000);
77 	printf("ipg clock     : %dHz\n", mx31_get_ipg_clk());
78 }
79 
80 void mx31_gpio_mux(unsigned long mode)
81 {
82 	unsigned long reg, shift, tmp;
83 
84 	reg = IOMUXC_BASE + (mode & 0x1fc);
85 	shift = (~mode & 0x3) * 8;
86 
87 	tmp = __REG(reg);
88 	tmp &= ~(0xff << shift);
89 	tmp |= ((mode >> IOMUX_MODE_POS) & 0xff) << shift;
90 	__REG(reg) = tmp;
91 }
92 
93 #if defined(CONFIG_DISPLAY_CPUINFO)
94 int print_cpuinfo (void)
95 {
96 	printf("CPU:   Freescale i.MX31 at %d MHz\n",
97 		mx31_get_mcu_main_clk() / 1000000);
98 	return 0;
99 }
100 #endif
101