xref: /linux/arch/openrisc/kernel/setup.c (revision 498d319bb512992ef0784c278fa03679f2f5649d)
1 /*
2  * OpenRISC setup.c
3  *
4  * Linux architectural port borrowing liberally from similar works of
5  * others.  All original copyrights apply as per the original source
6  * declaration.
7  *
8  * Modifications for the OpenRISC architecture:
9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11  *
12  *      This program is free software; you can redistribute it and/or
13  *      modify it under the terms of the GNU General Public License
14  *      as published by the Free Software Foundation; either version
15  *      2 of the License, or (at your option) any later version.
16  *
17  * This file handles the architecture-dependent parts of initialization
18  */
19 
20 #include <linux/errno.h>
21 #include <linux/sched.h>
22 #include <linux/kernel.h>
23 #include <linux/mm.h>
24 #include <linux/stddef.h>
25 #include <linux/unistd.h>
26 #include <linux/ptrace.h>
27 #include <linux/slab.h>
28 #include <linux/tty.h>
29 #include <linux/ioport.h>
30 #include <linux/delay.h>
31 #include <linux/console.h>
32 #include <linux/init.h>
33 #include <linux/bootmem.h>
34 #include <linux/seq_file.h>
35 #include <linux/serial.h>
36 #include <linux/initrd.h>
37 #include <linux/of_fdt.h>
38 #include <linux/of.h>
39 #include <linux/memblock.h>
40 #include <linux/device.h>
41 #include <linux/of_platform.h>
42 
43 #include <asm/segment.h>
44 #include <asm/pgtable.h>
45 #include <asm/types.h>
46 #include <asm/setup.h>
47 #include <asm/io.h>
48 #include <asm/cpuinfo.h>
49 #include <asm/delay.h>
50 
51 #include "vmlinux.h"
52 
53 static unsigned long __init setup_memory(void)
54 {
55 	unsigned long bootmap_size;
56 	unsigned long ram_start_pfn;
57 	unsigned long free_ram_start_pfn;
58 	unsigned long ram_end_pfn;
59 	phys_addr_t memory_start, memory_end;
60 	struct memblock_region *region;
61 
62 	memory_end = memory_start = 0;
63 
64 	/* Find main memory where is the kernel */
65 	for_each_memblock(memory, region) {
66 		memory_start = region->base;
67 		memory_end = region->base + region->size;
68 		printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
69 		       memory_start, memory_end);
70 	}
71 
72 	if (!memory_end) {
73 		panic("No memory!");
74 	}
75 
76 	ram_start_pfn = PFN_UP(memory_start);
77 	/* free_ram_start_pfn is first page after kernel */
78 	free_ram_start_pfn = PFN_UP(__pa(&_end));
79 	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
80 
81 	max_pfn = ram_end_pfn;
82 
83 	/*
84 	 * initialize the boot-time allocator (with low memory only).
85 	 *
86 	 * This makes the memory from the end of the kernel to the end of
87 	 * RAM usable.
88 	 * init_bootmem sets the global values min_low_pfn, max_low_pfn.
89 	 */
90 	bootmap_size = init_bootmem(free_ram_start_pfn,
91 				    ram_end_pfn - ram_start_pfn);
92 	free_bootmem(PFN_PHYS(free_ram_start_pfn),
93 		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
94 	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
95 			BOOTMEM_DEFAULT);
96 
97 	for_each_memblock(reserved, region) {
98 		printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
99 		       (u32) region->base, (u32) region->size);
100 		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
101 	}
102 
103 	return ram_end_pfn;
104 }
105 
106 struct cpuinfo cpuinfo;
107 
108 static void print_cpuinfo(void)
109 {
110 	unsigned long upr = mfspr(SPR_UPR);
111 	unsigned long vr = mfspr(SPR_VR);
112 	unsigned int version;
113 	unsigned int revision;
114 
115 	version = (vr & SPR_VR_VER) >> 24;
116 	revision = (vr & SPR_VR_REV);
117 
118 	printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
119 	       version, revision, cpuinfo.clock_frequency / 1000000);
120 
121 	if (!(upr & SPR_UPR_UP)) {
122 		printk(KERN_INFO
123 		       "-- no UPR register... unable to detect configuration\n");
124 		return;
125 	}
126 
127 	if (upr & SPR_UPR_DCP)
128 		printk(KERN_INFO
129 		       "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
130 		       cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
131 	else
132 		printk(KERN_INFO "-- dcache disabled\n");
133 	if (upr & SPR_UPR_ICP)
134 		printk(KERN_INFO
135 		       "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
136 		       cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
137 	else
138 		printk(KERN_INFO "-- icache disabled\n");
139 
140 	if (upr & SPR_UPR_DMP)
141 		printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
142 		       1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
143 		       1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
144 	if (upr & SPR_UPR_IMP)
145 		printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
146 		       1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
147 		       1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
148 
149 	printk(KERN_INFO "-- additional features:\n");
150 	if (upr & SPR_UPR_DUP)
151 		printk(KERN_INFO "-- debug unit\n");
152 	if (upr & SPR_UPR_PCUP)
153 		printk(KERN_INFO "-- performance counters\n");
154 	if (upr & SPR_UPR_PMP)
155 		printk(KERN_INFO "-- power management\n");
156 	if (upr & SPR_UPR_PICP)
157 		printk(KERN_INFO "-- PIC\n");
158 	if (upr & SPR_UPR_TTP)
159 		printk(KERN_INFO "-- timer\n");
160 	if (upr & SPR_UPR_CUP)
161 		printk(KERN_INFO "-- custom unit(s)\n");
162 }
163 
164 void __init setup_cpuinfo(void)
165 {
166 	struct device_node *cpu;
167 	unsigned long iccfgr, dccfgr;
168 	unsigned long cache_set_size, cache_ways;
169 
170 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
171 	if (!cpu)
172 		panic("No compatible CPU found in device tree...\n");
173 
174 	iccfgr = mfspr(SPR_ICCFGR);
175 	cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
176 	cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
177 	cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
178 	cpuinfo.icache_size =
179 	    cache_set_size * cache_ways * cpuinfo.icache_block_size;
180 
181 	dccfgr = mfspr(SPR_DCCFGR);
182 	cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
183 	cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
184 	cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
185 	cpuinfo.dcache_size =
186 	    cache_set_size * cache_ways * cpuinfo.dcache_block_size;
187 
188 	if (of_property_read_u32(cpu, "clock-frequency",
189 				 &cpuinfo.clock_frequency)) {
190 		printk(KERN_WARNING
191 		       "Device tree missing CPU 'clock-frequency' parameter."
192 		       "Assuming frequency 25MHZ"
193 		       "This is probably not what you want.");
194 	}
195 
196 	of_node_put(cpu);
197 
198 	print_cpuinfo();
199 }
200 
201 /**
202  * or32_early_setup
203  *
204  * Handles the pointer to the device tree that this kernel is to use
205  * for establishing the available platform devices.
206  *
207  * Falls back on built-in device tree in case null pointer is passed.
208  */
209 
210 void __init or32_early_setup(unsigned int fdt)
211 {
212 	if (fdt) {
213 		early_init_devtree((void*) fdt);
214 		printk(KERN_INFO "FDT at 0x%08x\n", fdt);
215 	} else {
216 		early_init_devtree(__dtb_start);
217 		printk(KERN_INFO "Compiled-in FDT at %p\n", __dtb_start);
218 	}
219 }
220 
221 static int __init openrisc_device_probe(void)
222 {
223 	of_platform_populate(NULL, NULL, NULL, NULL);
224 
225 	return 0;
226 }
227 
228 device_initcall(openrisc_device_probe);
229 
230 static inline unsigned long extract_value_bits(unsigned long reg,
231 					       short bit_nr, short width)
232 {
233 	return (reg >> bit_nr) & (0 << width);
234 }
235 
236 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
237 {
238 	while (!(mask & 0x1)) {
239 		reg = reg >> 1;
240 		mask = mask >> 1;
241 	}
242 	return mask & reg;
243 }
244 
245 void __init detect_unit_config(unsigned long upr, unsigned long mask,
246 			       char *text, void (*func) (void))
247 {
248 	if (text != NULL)
249 		printk("%s", text);
250 
251 	if (upr & mask) {
252 		if (func != NULL)
253 			func();
254 		else
255 			printk("present\n");
256 	} else
257 		printk("not present\n");
258 }
259 
260 /*
261  * calibrate_delay
262  *
263  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
264  * from the clock frequency passed in via the device tree
265  *
266  */
267 
268 void calibrate_delay(void)
269 {
270 	const int *val;
271 	struct device_node *cpu = NULL;
272 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
273 	val = of_get_property(cpu, "clock-frequency", NULL);
274 	if (!val)
275 		panic("no cpu 'clock-frequency' parameter in device tree");
276 	loops_per_jiffy = *val / HZ;
277 	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
278 		loops_per_jiffy / (500000 / HZ),
279 		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
280 }
281 
282 void __init setup_arch(char **cmdline_p)
283 {
284 	unsigned long max_low_pfn;
285 
286 	unflatten_and_copy_device_tree();
287 
288 	setup_cpuinfo();
289 
290 	/* process 1's initial memory region is the kernel code/data */
291 	init_mm.start_code = (unsigned long)&_stext;
292 	init_mm.end_code = (unsigned long)&_etext;
293 	init_mm.end_data = (unsigned long)&_edata;
294 	init_mm.brk = (unsigned long)&_end;
295 
296 #ifdef CONFIG_BLK_DEV_INITRD
297 	initrd_start = (unsigned long)&__initrd_start;
298 	initrd_end = (unsigned long)&__initrd_end;
299 	if (initrd_start == initrd_end) {
300 		initrd_start = 0;
301 		initrd_end = 0;
302 	}
303 	initrd_below_start_ok = 1;
304 #endif
305 
306 	/* setup bootmem allocator */
307 	max_low_pfn = setup_memory();
308 
309 	/* paging_init() sets up the MMU and marks all pages as reserved */
310 	paging_init();
311 
312 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
313 	if (!conswitchp)
314 		conswitchp = &dummy_con;
315 #endif
316 
317 	*cmdline_p = boot_command_line;
318 
319 	printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
320 }
321 
322 static int show_cpuinfo(struct seq_file *m, void *v)
323 {
324 	unsigned long vr;
325 	int version, revision;
326 
327 	vr = mfspr(SPR_VR);
328 	version = (vr & SPR_VR_VER) >> 24;
329 	revision = vr & SPR_VR_REV;
330 
331 	return seq_printf(m,
332 			  "cpu\t\t: OpenRISC-%x\n"
333 			  "revision\t: %d\n"
334 			  "frequency\t: %ld\n"
335 			  "dcache size\t: %d bytes\n"
336 			  "dcache block size\t: %d bytes\n"
337 			  "icache size\t: %d bytes\n"
338 			  "icache block size\t: %d bytes\n"
339 			  "immu\t\t: %d entries, %lu ways\n"
340 			  "dmmu\t\t: %d entries, %lu ways\n"
341 			  "bogomips\t: %lu.%02lu\n",
342 			  version,
343 			  revision,
344 			  loops_per_jiffy * HZ,
345 			  cpuinfo.dcache_size,
346 			  cpuinfo.dcache_block_size,
347 			  cpuinfo.icache_size,
348 			  cpuinfo.icache_block_size,
349 			  1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
350 			  1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
351 			  1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
352 			  1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
353 			  (loops_per_jiffy * HZ) / 500000,
354 			  ((loops_per_jiffy * HZ) / 5000) % 100);
355 }
356 
357 static void *c_start(struct seq_file *m, loff_t * pos)
358 {
359 	/* We only have one CPU... */
360 	return *pos < 1 ? (void *)1 : NULL;
361 }
362 
363 static void *c_next(struct seq_file *m, void *v, loff_t * pos)
364 {
365 	++*pos;
366 	return NULL;
367 }
368 
369 static void c_stop(struct seq_file *m, void *v)
370 {
371 }
372 
373 const struct seq_operations cpuinfo_op = {
374 	.start = c_start,
375 	.next = c_next,
376 	.stop = c_stop,
377 	.show = show_cpuinfo,
378 };
379