xref: /linux/arch/arm/mach-imx/cpu-imx5.c (revision 9ce28d827f74d0acdd058bded8bab5309b0f5c8f)
1 /*
2  * Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
3  *
4  * The code contained herein is licensed under the GNU General Public
5  * License. You may obtain a copy of the GNU General Public License
6  * Version 2 or later at the following locations:
7  *
8  * http://www.opensource.org/licenses/gpl-license.html
9  * http://www.gnu.org/copyleft/gpl.html
10  *
11  * This file contains the CPU initialization code.
12  */
13 
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <mach/hardware.h>
19 #include <linux/io.h>
20 
21 static int mx5_cpu_rev = -1;
22 
23 #define IIM_SREV 0x24
24 #define MX50_HW_ADADIG_DIGPROG	0xB0
25 
26 static int get_mx51_srev(void)
27 {
28 	void __iomem *iim_base = MX51_IO_ADDRESS(MX51_IIM_BASE_ADDR);
29 	u32 rev = readl(iim_base + IIM_SREV) & 0xff;
30 
31 	switch (rev) {
32 	case 0x0:
33 		return IMX_CHIP_REVISION_2_0;
34 	case 0x10:
35 		return IMX_CHIP_REVISION_3_0;
36 	default:
37 		return IMX_CHIP_REVISION_UNKNOWN;
38 	}
39 }
40 
41 /*
42  * Returns:
43  *	the silicon revision of the cpu
44  *	-EINVAL - not a mx51
45  */
46 int mx51_revision(void)
47 {
48 	if (!cpu_is_mx51())
49 		return -EINVAL;
50 
51 	if (mx5_cpu_rev == -1)
52 		mx5_cpu_rev = get_mx51_srev();
53 
54 	return mx5_cpu_rev;
55 }
56 EXPORT_SYMBOL(mx51_revision);
57 
58 #ifdef CONFIG_NEON
59 
60 /*
61  * All versions of the silicon before Rev. 3 have broken NEON implementations.
62  * Dependent on link order - so the assumption is that vfp_init is called
63  * before us.
64  */
65 static int __init mx51_neon_fixup(void)
66 {
67 	if (!cpu_is_mx51())
68 		return 0;
69 
70 	if (mx51_revision() < IMX_CHIP_REVISION_3_0 &&
71 			(elf_hwcap & HWCAP_NEON)) {
72 		elf_hwcap &= ~HWCAP_NEON;
73 		pr_info("Turning off NEON support, detected broken NEON implementation\n");
74 	}
75 	return 0;
76 }
77 
78 late_initcall(mx51_neon_fixup);
79 #endif
80 
81 static int get_mx53_srev(void)
82 {
83 	void __iomem *iim_base = MX51_IO_ADDRESS(MX53_IIM_BASE_ADDR);
84 	u32 rev = readl(iim_base + IIM_SREV) & 0xff;
85 
86 	switch (rev) {
87 	case 0x0:
88 		return IMX_CHIP_REVISION_1_0;
89 	case 0x2:
90 		return IMX_CHIP_REVISION_2_0;
91 	case 0x3:
92 		return IMX_CHIP_REVISION_2_1;
93 	default:
94 		return IMX_CHIP_REVISION_UNKNOWN;
95 	}
96 }
97 
98 /*
99  * Returns:
100  *	the silicon revision of the cpu
101  *	-EINVAL - not a mx53
102  */
103 int mx53_revision(void)
104 {
105 	if (!cpu_is_mx53())
106 		return -EINVAL;
107 
108 	if (mx5_cpu_rev == -1)
109 		mx5_cpu_rev = get_mx53_srev();
110 
111 	return mx5_cpu_rev;
112 }
113 EXPORT_SYMBOL(mx53_revision);
114 
115 static int get_mx50_srev(void)
116 {
117 	void __iomem *anatop = ioremap(MX50_ANATOP_BASE_ADDR, SZ_8K);
118 	u32 rev;
119 
120 	if (!anatop) {
121 		mx5_cpu_rev = -EINVAL;
122 		return 0;
123 	}
124 
125 	rev = readl(anatop + MX50_HW_ADADIG_DIGPROG);
126 	rev &= 0xff;
127 
128 	iounmap(anatop);
129 	if (rev == 0x0)
130 		return IMX_CHIP_REVISION_1_0;
131 	else if (rev == 0x1)
132 		return IMX_CHIP_REVISION_1_1;
133 	return 0;
134 }
135 
136 /*
137  * Returns:
138  *	the silicon revision of the cpu
139  *	-EINVAL - not a mx50
140  */
141 int mx50_revision(void)
142 {
143 	if (!cpu_is_mx50())
144 		return -EINVAL;
145 
146 	if (mx5_cpu_rev == -1)
147 		mx5_cpu_rev = get_mx50_srev();
148 
149 	return mx5_cpu_rev;
150 }
151 EXPORT_SYMBOL(mx50_revision);
152 
153 static int __init post_cpu_init(void)
154 {
155 	unsigned int reg;
156 	void __iomem *base;
157 
158 	if (cpu_is_mx51() || cpu_is_mx53()) {
159 		if (cpu_is_mx51())
160 			base = MX51_IO_ADDRESS(MX51_AIPS1_BASE_ADDR);
161 		else
162 			base = MX53_IO_ADDRESS(MX53_AIPS1_BASE_ADDR);
163 
164 		__raw_writel(0x0, base + 0x40);
165 		__raw_writel(0x0, base + 0x44);
166 		__raw_writel(0x0, base + 0x48);
167 		__raw_writel(0x0, base + 0x4C);
168 		reg = __raw_readl(base + 0x50) & 0x00FFFFFF;
169 		__raw_writel(reg, base + 0x50);
170 
171 		if (cpu_is_mx51())
172 			base = MX51_IO_ADDRESS(MX51_AIPS2_BASE_ADDR);
173 		else
174 			base = MX53_IO_ADDRESS(MX53_AIPS2_BASE_ADDR);
175 
176 		__raw_writel(0x0, base + 0x40);
177 		__raw_writel(0x0, base + 0x44);
178 		__raw_writel(0x0, base + 0x48);
179 		__raw_writel(0x0, base + 0x4C);
180 		reg = __raw_readl(base + 0x50) & 0x00FFFFFF;
181 		__raw_writel(reg, base + 0x50);
182 	}
183 
184 	return 0;
185 }
186 
187 postcore_initcall(post_cpu_init);
188