xref: /linux/arch/openrisc/kernel/setup.c (revision ec0c2d5359e2f288d75d98465829d31c6d26da47)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * OpenRISC setup.c
4  *
5  * Linux architectural port borrowing liberally from similar works of
6  * others.  All original copyrights apply as per the original source
7  * declaration.
8  *
9  * Modifications for the OpenRISC architecture:
10  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12  *
13  * This file handles the architecture-dependent parts of initialization
14  */
15 
16 #include <linux/errno.h>
17 #include <linux/sched.h>
18 #include <linux/kernel.h>
19 #include <linux/mm.h>
20 #include <linux/stddef.h>
21 #include <linux/unistd.h>
22 #include <linux/ptrace.h>
23 #include <linux/slab.h>
24 #include <linux/tty.h>
25 #include <linux/ioport.h>
26 #include <linux/delay.h>
27 #include <linux/console.h>
28 #include <linux/init.h>
29 #include <linux/memblock.h>
30 #include <linux/seq_file.h>
31 #include <linux/serial.h>
32 #include <linux/initrd.h>
33 #include <linux/of_fdt.h>
34 #include <linux/of.h>
35 #include <linux/device.h>
36 
37 #include <asm/sections.h>
38 #include <asm/types.h>
39 #include <asm/setup.h>
40 #include <asm/io.h>
41 #include <asm/cpuinfo.h>
42 #include <asm/delay.h>
43 
44 #include "vmlinux.h"
45 
setup_memory(void)46 static void __init setup_memory(void)
47 {
48 	unsigned long ram_start_pfn;
49 	unsigned long ram_end_pfn;
50 	phys_addr_t memory_start, memory_end;
51 
52 	memory_end = memory_start = 0;
53 
54 	/* Find main memory where is the kernel, we assume its the only one */
55 	memory_start = memblock_start_of_DRAM();
56 	memory_end = memblock_end_of_DRAM();
57 
58 	if (!memory_end) {
59 		panic("No memory!");
60 	}
61 
62 	ram_start_pfn = PFN_UP(memory_start);
63 	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
64 
65 	/* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
66 	min_low_pfn = ram_start_pfn;
67 	max_low_pfn = ram_end_pfn;
68 	max_pfn = ram_end_pfn;
69 
70 	/*
71 	 * initialize the boot-time allocator (with low memory only).
72 	 *
73 	 * This makes the memory from the end of the kernel to the end of
74 	 * RAM usable.
75 	 */
76 	memblock_reserve(__pa(_stext), _end - _stext);
77 
78 #ifdef CONFIG_BLK_DEV_INITRD
79 	/* Then reserve the initrd, if any */
80 	if (initrd_start && (initrd_end > initrd_start)) {
81 		unsigned long aligned_start = ALIGN_DOWN(initrd_start, PAGE_SIZE);
82 		unsigned long aligned_end = ALIGN(initrd_end, PAGE_SIZE);
83 
84 		memblock_reserve(__pa(aligned_start), aligned_end - aligned_start);
85 	}
86 #endif /* CONFIG_BLK_DEV_INITRD */
87 
88 	early_init_fdt_reserve_self();
89 	early_init_fdt_scan_reserved_mem();
90 
91 	memblock_dump_all();
92 }
93 
94 struct cpuinfo_or1k cpuinfo_or1k[NR_CPUS];
95 
print_cpuinfo(void)96 static void print_cpuinfo(void)
97 {
98 	unsigned long upr = mfspr(SPR_UPR);
99 	unsigned long vr = mfspr(SPR_VR);
100 	unsigned int version;
101 	unsigned int revision;
102 	struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
103 
104 	version = (vr & SPR_VR_VER) >> 24;
105 	revision = (vr & SPR_VR_REV);
106 
107 	printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
108 	       version, revision, cpuinfo->clock_frequency / 1000000);
109 
110 	if (!(upr & SPR_UPR_UP)) {
111 		printk(KERN_INFO
112 		       "-- no UPR register... unable to detect configuration\n");
113 		return;
114 	}
115 
116 	if (upr & SPR_UPR_DMP)
117 		printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
118 		       1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
119 		       1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
120 	if (upr & SPR_UPR_IMP)
121 		printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
122 		       1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
123 		       1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
124 
125 	printk(KERN_INFO "-- additional features:\n");
126 	if (upr & SPR_UPR_DUP)
127 		printk(KERN_INFO "-- debug unit\n");
128 	if (upr & SPR_UPR_PCUP)
129 		printk(KERN_INFO "-- performance counters\n");
130 	if (upr & SPR_UPR_PMP)
131 		printk(KERN_INFO "-- power management\n");
132 	if (upr & SPR_UPR_PICP)
133 		printk(KERN_INFO "-- PIC\n");
134 	if (upr & SPR_UPR_TTP)
135 		printk(KERN_INFO "-- timer\n");
136 	if (upr & SPR_UPR_CUP)
137 		printk(KERN_INFO "-- custom unit(s)\n");
138 }
139 
setup_cpuinfo(void)140 void __init setup_cpuinfo(void)
141 {
142 	struct device_node *cpu;
143 	int cpu_id = smp_processor_id();
144 	struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[cpu_id];
145 
146 	cpu = of_get_cpu_node(cpu_id, NULL);
147 	if (!cpu)
148 		panic("Couldn't find CPU%d in device tree...\n", cpu_id);
149 
150 	if (of_property_read_u32(cpu, "clock-frequency",
151 				 &cpuinfo->clock_frequency)) {
152 		printk(KERN_WARNING
153 		       "Device tree missing CPU 'clock-frequency' parameter."
154 		       "Assuming frequency 25MHZ"
155 		       "This is probably not what you want.");
156 	}
157 
158 	cpuinfo->coreid = mfspr(SPR_COREID);
159 
160 	of_node_put(cpu);
161 
162 	print_cpuinfo();
163 }
164 
165 /**
166  * or1k_early_setup
167  * @fdt: pointer to the start of the device tree in memory or NULL
168  *
169  * Handles the pointer to the device tree that this kernel is to use
170  * for establishing the available platform devices.
171  *
172  * Falls back on built-in device tree in case null pointer is passed.
173  */
174 
or1k_early_setup(void * fdt)175 void __init or1k_early_setup(void *fdt)
176 {
177 	if (fdt)
178 		pr_info("FDT at %p\n", fdt);
179 	else {
180 		fdt = __dtb_start;
181 		pr_info("Compiled-in FDT at %p\n", fdt);
182 	}
183 	early_init_devtree(fdt);
184 }
185 
extract_value_bits(unsigned long reg,short bit_nr,short width)186 static inline unsigned long extract_value_bits(unsigned long reg,
187 					       short bit_nr, short width)
188 {
189 	return (reg >> bit_nr) & (0 << width);
190 }
191 
extract_value(unsigned long reg,unsigned long mask)192 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
193 {
194 	while (!(mask & 0x1)) {
195 		reg = reg >> 1;
196 		mask = mask >> 1;
197 	}
198 	return mask & reg;
199 }
200 
201 /*
202  * calibrate_delay
203  *
204  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
205  * from the clock frequency passed in via the device tree
206  *
207  */
208 
calibrate_delay(void)209 void calibrate_delay(void)
210 {
211 	const int *val;
212 	struct device_node *cpu = of_get_cpu_node(smp_processor_id(), NULL);
213 
214 	val = of_get_property(cpu, "clock-frequency", NULL);
215 	if (!val)
216 		panic("no cpu 'clock-frequency' parameter in device tree");
217 	loops_per_jiffy = *val / HZ;
218 	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
219 		loops_per_jiffy / (500000 / HZ),
220 		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
221 
222 	of_node_put(cpu);
223 }
224 
setup_arch(char ** cmdline_p)225 void __init setup_arch(char **cmdline_p)
226 {
227 	/* setup memblock allocator */
228 	setup_memory();
229 
230 	unflatten_and_copy_device_tree();
231 
232 	setup_cpuinfo();
233 
234 #ifdef CONFIG_SMP
235 	smp_init_cpus();
236 #endif
237 
238 	/* process 1's initial memory region is the kernel code/data */
239 	setup_initial_init_mm(_stext, _etext, _edata, _end);
240 
241 #ifdef CONFIG_BLK_DEV_INITRD
242 	if (initrd_start == initrd_end) {
243 		printk(KERN_INFO "Initial ramdisk not found\n");
244 		initrd_start = 0;
245 		initrd_end = 0;
246 	} else {
247 		printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
248 		       (void *)(initrd_start), initrd_end - initrd_start);
249 		initrd_below_start_ok = 1;
250 	}
251 #endif
252 
253 	/* paging_init() sets up the MMU and marks all pages as reserved */
254 	paging_init();
255 
256 	*cmdline_p = boot_command_line;
257 
258 	printk(KERN_INFO "OpenRISC Linux -- http://openrisc.io\n");
259 }
260 
show_cpuinfo(struct seq_file * m,void * v)261 static int show_cpuinfo(struct seq_file *m, void *v)
262 {
263 	unsigned int vr, cpucfgr;
264 	unsigned int avr;
265 	unsigned int version;
266 #ifdef CONFIG_SMP
267 	struct cpuinfo_or1k *cpuinfo = v;
268 	seq_printf(m, "processor\t\t: %d\n", cpuinfo->coreid);
269 #endif
270 
271 	vr = mfspr(SPR_VR);
272 	cpucfgr = mfspr(SPR_CPUCFGR);
273 
274 	if (vr & SPR_VR_UVRP) {
275 		vr = mfspr(SPR_VR2);
276 		version = vr & SPR_VR2_VER;
277 		avr = mfspr(SPR_AVR);
278 		seq_printf(m, "cpu architecture\t: "
279 			   "OpenRISC 1000 (%d.%d-rev%d)\n",
280 			   (avr >> 24) & 0xff,
281 			   (avr >> 16) & 0xff,
282 			   (avr >> 8) & 0xff);
283 		seq_printf(m, "cpu implementation id\t: 0x%x\n",
284 			   (vr & SPR_VR2_CPUID) >> 24);
285 		seq_printf(m, "cpu version\t\t: 0x%x\n", version);
286 	} else {
287 		version = (vr & SPR_VR_VER) >> 24;
288 		seq_printf(m, "cpu\t\t\t: OpenRISC-%x\n", version);
289 		seq_printf(m, "revision\t\t: %d\n", vr & SPR_VR_REV);
290 	}
291 	seq_printf(m, "frequency\t\t: %ld\n", loops_per_jiffy * HZ);
292 	seq_printf(m, "immu\t\t\t: %d entries, %lu ways\n",
293 		   1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
294 		   1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
295 	seq_printf(m, "dmmu\t\t\t: %d entries, %lu ways\n",
296 		   1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
297 		   1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
298 	seq_printf(m, "bogomips\t\t: %lu.%02lu\n",
299 		   (loops_per_jiffy * HZ) / 500000,
300 		   ((loops_per_jiffy * HZ) / 5000) % 100);
301 
302 	seq_puts(m, "features\t\t: ");
303 	seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OB32S ? "orbis32" : "");
304 	seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OB64S ? "orbis64" : "");
305 	seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OF32S ? "orfpx32" : "");
306 	seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OF64S ? "orfpx64" : "");
307 	seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OV64S ? "orvdx64" : "");
308 	seq_puts(m, "\n");
309 
310 	seq_puts(m, "\n");
311 
312 	return 0;
313 }
314 
c_start(struct seq_file * m,loff_t * pos)315 static void *c_start(struct seq_file *m, loff_t *pos)
316 {
317 	*pos = cpumask_next(*pos - 1, cpu_online_mask);
318 	if ((*pos) < nr_cpu_ids)
319 		return &cpuinfo_or1k[*pos];
320 	return NULL;
321 }
322 
c_next(struct seq_file * m,void * v,loff_t * pos)323 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
324 {
325 	(*pos)++;
326 	return c_start(m, pos);
327 }
328 
c_stop(struct seq_file * m,void * v)329 static void c_stop(struct seq_file *m, void *v)
330 {
331 }
332 
333 const struct seq_operations cpuinfo_op = {
334 	.start = c_start,
335 	.next = c_next,
336 	.stop = c_stop,
337 	.show = show_cpuinfo,
338 };
339