xref: /openbmc/u-boot/arch/nios2/cpu/cpu.c (revision 87a62bce)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
4  * Scott McNutt <smcnutt@psyent.com>
5  */
6 
7 #include <common.h>
8 #include <cpu.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <asm/cache.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 #ifdef CONFIG_DISPLAY_CPUINFO
16 int print_cpuinfo(void)
17 {
18 	printf("CPU:   Nios-II\n");
19 	return 0;
20 }
21 #endif /* CONFIG_DISPLAY_CPUINFO */
22 
23 #ifdef CONFIG_ALTERA_SYSID
24 int checkboard(void)
25 {
26 	display_sysid();
27 	return 0;
28 }
29 #endif
30 
31 int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
32 {
33 	disable_interrupts();
34 	/* indirect call to go beyond 256MB limitation of toolchain */
35 	nios2_callr(gd->arch.reset_addr);
36 	return 0;
37 }
38 
39 /*
40  * COPY EXCEPTION TRAMPOLINE -- copy the tramp to the
41  * exception address. Define CONFIG_ROM_STUBS to prevent
42  * the copy (e.g. exception in flash or in other
43  * softare/firmware component).
44  */
45 #ifndef CONFIG_ROM_STUBS
46 static void copy_exception_trampoline(void)
47 {
48 	extern int _except_start, _except_end;
49 	void *except_target = (void *)gd->arch.exception_addr;
50 
51 	if (&_except_start != except_target) {
52 		memcpy(except_target, &_except_start,
53 		       &_except_end - &_except_start);
54 		flush_cache(gd->arch.exception_addr,
55 			    &_except_end - &_except_start);
56 	}
57 }
58 #endif
59 
60 int arch_cpu_init_dm(void)
61 {
62 	struct udevice *dev;
63 	int ret;
64 
65 	ret = uclass_first_device_err(UCLASS_CPU, &dev);
66 	if (ret)
67 		return ret;
68 
69 	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
70 #ifndef CONFIG_ROM_STUBS
71 	copy_exception_trampoline();
72 #endif
73 
74 	return 0;
75 }
76 
77 static int altera_nios2_get_desc(struct udevice *dev, char *buf, int size)
78 {
79 	const char *cpu_name = "Nios-II";
80 
81 	if (size < strlen(cpu_name))
82 		return -ENOSPC;
83 	strcpy(buf, cpu_name);
84 
85 	return 0;
86 }
87 
88 static int altera_nios2_get_info(struct udevice *dev, struct cpu_info *info)
89 {
90 	info->cpu_freq = gd->cpu_clk;
91 	info->features = (1 << CPU_FEAT_L1_CACHE) |
92 		(gd->arch.has_mmu ? (1 << CPU_FEAT_MMU) : 0);
93 
94 	return 0;
95 }
96 
97 static int altera_nios2_get_count(struct udevice *dev)
98 {
99 	return 1;
100 }
101 
102 static int altera_nios2_probe(struct udevice *dev)
103 {
104 	const void *blob = gd->fdt_blob;
105 	int node = dev_of_offset(dev);
106 
107 	gd->cpu_clk = fdtdec_get_int(blob, node,
108 		"clock-frequency", 0);
109 	gd->arch.dcache_line_size = fdtdec_get_int(blob, node,
110 		"dcache-line-size", 0);
111 	gd->arch.icache_line_size = fdtdec_get_int(blob, node,
112 		"icache-line-size", 0);
113 	gd->arch.dcache_size = fdtdec_get_int(blob, node,
114 		"dcache-size", 0);
115 	gd->arch.icache_size = fdtdec_get_int(blob, node,
116 		"icache-size", 0);
117 	gd->arch.reset_addr = fdtdec_get_int(blob, node,
118 		"altr,reset-addr", 0);
119 	gd->arch.exception_addr = fdtdec_get_int(blob, node,
120 		"altr,exception-addr", 0);
121 	gd->arch.has_initda = fdtdec_get_int(blob, node,
122 		"altr,has-initda", 0);
123 	gd->arch.has_mmu = fdtdec_get_int(blob, node,
124 		"altr,has-mmu", 0);
125 	gd->arch.io_region_base = gd->arch.has_mmu ? 0xe0000000 : 0x80000000;
126 	gd->arch.mem_region_base = gd->arch.has_mmu ? 0xc0000000 : 0x00000000;
127 	gd->arch.physaddr_mask = gd->arch.has_mmu ? 0x1fffffff : 0x7fffffff;
128 
129 	return 0;
130 }
131 
132 static const struct cpu_ops altera_nios2_ops = {
133 	.get_desc	= altera_nios2_get_desc,
134 	.get_info	= altera_nios2_get_info,
135 	.get_count	= altera_nios2_get_count,
136 };
137 
138 static const struct udevice_id altera_nios2_ids[] = {
139 	{ .compatible = "altr,nios2-1.0" },
140 	{ .compatible = "altr,nios2-1.1" },
141 	{ }
142 };
143 
144 U_BOOT_DRIVER(altera_nios2) = {
145 	.name		= "altera_nios2",
146 	.id		= UCLASS_CPU,
147 	.of_match	= altera_nios2_ids,
148 	.probe		= altera_nios2_probe,
149 	.ops		= &altera_nios2_ops,
150 	.flags		= DM_FLAG_PRE_RELOC,
151 };
152 
153 /* This is a dummy function on nios2 */
154 int dram_init(void)
155 {
156 	return 0;
157 }
158