xref: /openbmc/u-boot/arch/nios2/cpu/cpu.c (revision 24b852a7)
1 /*
2  * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
3  * Scott McNutt <smcnutt@psyent.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <cpu.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <asm/cache.h>
13 
14 DECLARE_GLOBAL_DATA_PTR;
15 
16 #ifdef CONFIG_DISPLAY_CPUINFO
17 int print_cpuinfo(void)
18 {
19 	printf("CPU:   Nios-II\n");
20 	return 0;
21 }
22 #endif /* CONFIG_DISPLAY_CPUINFO */
23 
24 int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
25 {
26 	disable_interrupts();
27 	/* indirect call to go beyond 256MB limitation of toolchain */
28 	nios2_callr(gd->arch.reset_addr);
29 	return 0;
30 }
31 
32 /*
33  * COPY EXCEPTION TRAMPOLINE -- copy the tramp to the
34  * exception address. Define CONFIG_ROM_STUBS to prevent
35  * the copy (e.g. exception in flash or in other
36  * softare/firmware component).
37  */
38 #ifndef CONFIG_ROM_STUBS
39 static void copy_exception_trampoline(void)
40 {
41 	extern int _except_start, _except_end;
42 	void *except_target = (void *)gd->arch.exception_addr;
43 
44 	if (&_except_start != except_target) {
45 		memcpy(except_target, &_except_start,
46 		       &_except_end - &_except_start);
47 		flush_cache(gd->arch.exception_addr,
48 			    &_except_end - &_except_start);
49 	}
50 }
51 #endif
52 
53 int arch_cpu_init_dm(void)
54 {
55 	struct udevice *dev;
56 	int ret;
57 
58 	ret = uclass_first_device(UCLASS_CPU, &dev);
59 	if (ret)
60 		return ret;
61 	if (!dev)
62 		return -ENODEV;
63 
64 	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
65 #ifndef CONFIG_ROM_STUBS
66 	copy_exception_trampoline();
67 #endif
68 
69 	return 0;
70 }
71 
72 static int altera_nios2_get_desc(struct udevice *dev, char *buf, int size)
73 {
74 	const char *cpu_name = "Nios-II";
75 
76 	if (size < strlen(cpu_name))
77 		return -ENOSPC;
78 	strcpy(buf, cpu_name);
79 
80 	return 0;
81 }
82 
83 static int altera_nios2_get_info(struct udevice *dev, struct cpu_info *info)
84 {
85 	info->cpu_freq = gd->cpu_clk;
86 	info->features = (1 << CPU_FEAT_L1_CACHE) |
87 		(gd->arch.has_mmu ? (1 << CPU_FEAT_MMU) : 0);
88 
89 	return 0;
90 }
91 
92 static int altera_nios2_get_count(struct udevice *dev)
93 {
94 	return 1;
95 }
96 
97 static int altera_nios2_probe(struct udevice *dev)
98 {
99 	const void *blob = gd->fdt_blob;
100 	int node = dev->of_offset;
101 
102 	gd->cpu_clk = fdtdec_get_int(blob, node,
103 		"clock-frequency", 0);
104 	gd->arch.dcache_line_size = fdtdec_get_int(blob, node,
105 		"dcache-line-size", 0);
106 	gd->arch.icache_line_size = fdtdec_get_int(blob, node,
107 		"icache-line-size", 0);
108 	gd->arch.dcache_size = fdtdec_get_int(blob, node,
109 		"dcache-size", 0);
110 	gd->arch.icache_size = fdtdec_get_int(blob, node,
111 		"icache-size", 0);
112 	gd->arch.reset_addr = fdtdec_get_int(blob, node,
113 		"altr,reset-addr", 0);
114 	gd->arch.exception_addr = fdtdec_get_int(blob, node,
115 		"altr,exception-addr", 0);
116 	gd->arch.has_initda = fdtdec_get_int(blob, node,
117 		"altr,has-initda", 0);
118 	gd->arch.has_mmu = fdtdec_get_int(blob, node,
119 		"altr,has-mmu", 0);
120 	gd->arch.io_region_base = gd->arch.has_mmu ? 0xe0000000 : 0x80000000;
121 	gd->arch.mem_region_base = gd->arch.has_mmu ? 0xc0000000 : 0x00000000;
122 	gd->arch.physaddr_mask = gd->arch.has_mmu ? 0x1fffffff : 0x7fffffff;
123 
124 	return 0;
125 }
126 
127 static const struct cpu_ops altera_nios2_ops = {
128 	.get_desc	= altera_nios2_get_desc,
129 	.get_info	= altera_nios2_get_info,
130 	.get_count	= altera_nios2_get_count,
131 };
132 
133 static const struct udevice_id altera_nios2_ids[] = {
134 	{ .compatible = "altr,nios2-1.0" },
135 	{ .compatible = "altr,nios2-1.1" },
136 	{ }
137 };
138 
139 U_BOOT_DRIVER(altera_nios2) = {
140 	.name		= "altera_nios2",
141 	.id		= UCLASS_CPU,
142 	.of_match	= altera_nios2_ids,
143 	.probe		= altera_nios2_probe,
144 	.ops		= &altera_nios2_ops,
145 	.flags		= DM_FLAG_PRE_RELOC,
146 };
147