xref: /openbmc/u-boot/arch/nios2/cpu/cpu.c (revision 7b384eccc785b596f68448b155cbda26df57fb23)
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