xref: /linux/arch/openrisc/kernel/setup.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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/sections.h>
44 #include <asm/segment.h>
45 #include <asm/pgtable.h>
46 #include <asm/types.h>
47 #include <asm/setup.h>
48 #include <asm/io.h>
49 #include <asm/cpuinfo.h>
50 #include <asm/delay.h>
51 
52 #include "vmlinux.h"
53 
54 static unsigned long __init setup_memory(void)
55 {
56 	unsigned long bootmap_size;
57 	unsigned long ram_start_pfn;
58 	unsigned long free_ram_start_pfn;
59 	unsigned long ram_end_pfn;
60 	phys_addr_t memory_start, memory_end;
61 	struct memblock_region *region;
62 
63 	memory_end = memory_start = 0;
64 
65 	/* Find main memory where is the kernel */
66 	for_each_memblock(memory, region) {
67 		memory_start = region->base;
68 		memory_end = region->base + region->size;
69 		printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
70 		       memory_start, memory_end);
71 	}
72 
73 	if (!memory_end) {
74 		panic("No memory!");
75 	}
76 
77 	ram_start_pfn = PFN_UP(memory_start);
78 	/* free_ram_start_pfn is first page after kernel */
79 	free_ram_start_pfn = PFN_UP(__pa(_end));
80 	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
81 
82 	max_pfn = ram_end_pfn;
83 
84 	/*
85 	 * initialize the boot-time allocator (with low memory only).
86 	 *
87 	 * This makes the memory from the end of the kernel to the end of
88 	 * RAM usable.
89 	 * init_bootmem sets the global values min_low_pfn, max_low_pfn.
90 	 */
91 	bootmap_size = init_bootmem(free_ram_start_pfn,
92 				    ram_end_pfn - ram_start_pfn);
93 	free_bootmem(PFN_PHYS(free_ram_start_pfn),
94 		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
95 	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
96 			BOOTMEM_DEFAULT);
97 
98 	for_each_memblock(reserved, region) {
99 		printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
100 		       (u32) region->base, (u32) region->size);
101 		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
102 	}
103 
104 	return ram_end_pfn;
105 }
106 
107 struct cpuinfo cpuinfo;
108 
109 static void print_cpuinfo(void)
110 {
111 	unsigned long upr = mfspr(SPR_UPR);
112 	unsigned long vr = mfspr(SPR_VR);
113 	unsigned int version;
114 	unsigned int revision;
115 
116 	version = (vr & SPR_VR_VER) >> 24;
117 	revision = (vr & SPR_VR_REV);
118 
119 	printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
120 	       version, revision, cpuinfo.clock_frequency / 1000000);
121 
122 	if (!(upr & SPR_UPR_UP)) {
123 		printk(KERN_INFO
124 		       "-- no UPR register... unable to detect configuration\n");
125 		return;
126 	}
127 
128 	if (upr & SPR_UPR_DCP)
129 		printk(KERN_INFO
130 		       "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
131 		       cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
132 	else
133 		printk(KERN_INFO "-- dcache disabled\n");
134 	if (upr & SPR_UPR_ICP)
135 		printk(KERN_INFO
136 		       "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
137 		       cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
138 	else
139 		printk(KERN_INFO "-- icache disabled\n");
140 
141 	if (upr & SPR_UPR_DMP)
142 		printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
143 		       1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
144 		       1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
145 	if (upr & SPR_UPR_IMP)
146 		printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
147 		       1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
148 		       1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
149 
150 	printk(KERN_INFO "-- additional features:\n");
151 	if (upr & SPR_UPR_DUP)
152 		printk(KERN_INFO "-- debug unit\n");
153 	if (upr & SPR_UPR_PCUP)
154 		printk(KERN_INFO "-- performance counters\n");
155 	if (upr & SPR_UPR_PMP)
156 		printk(KERN_INFO "-- power management\n");
157 	if (upr & SPR_UPR_PICP)
158 		printk(KERN_INFO "-- PIC\n");
159 	if (upr & SPR_UPR_TTP)
160 		printk(KERN_INFO "-- timer\n");
161 	if (upr & SPR_UPR_CUP)
162 		printk(KERN_INFO "-- custom unit(s)\n");
163 }
164 
165 void __init setup_cpuinfo(void)
166 {
167 	struct device_node *cpu;
168 	unsigned long iccfgr, dccfgr;
169 	unsigned long cache_set_size, cache_ways;
170 
171 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
172 	if (!cpu)
173 		panic("No compatible CPU found in device tree...\n");
174 
175 	iccfgr = mfspr(SPR_ICCFGR);
176 	cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
177 	cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
178 	cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
179 	cpuinfo.icache_size =
180 	    cache_set_size * cache_ways * cpuinfo.icache_block_size;
181 
182 	dccfgr = mfspr(SPR_DCCFGR);
183 	cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
184 	cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
185 	cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
186 	cpuinfo.dcache_size =
187 	    cache_set_size * cache_ways * cpuinfo.dcache_block_size;
188 
189 	if (of_property_read_u32(cpu, "clock-frequency",
190 				 &cpuinfo.clock_frequency)) {
191 		printk(KERN_WARNING
192 		       "Device tree missing CPU 'clock-frequency' parameter."
193 		       "Assuming frequency 25MHZ"
194 		       "This is probably not what you want.");
195 	}
196 
197 	of_node_put(cpu);
198 
199 	print_cpuinfo();
200 }
201 
202 /**
203  * or32_early_setup
204  *
205  * Handles the pointer to the device tree that this kernel is to use
206  * for establishing the available platform devices.
207  *
208  * Falls back on built-in device tree in case null pointer is passed.
209  */
210 
211 void __init or32_early_setup(void *fdt)
212 {
213 	if (fdt)
214 		pr_info("FDT at %p\n", fdt);
215 	else {
216 		fdt = __dtb_start;
217 		pr_info("Compiled-in FDT at %p\n", fdt);
218 	}
219 	early_init_devtree(fdt);
220 }
221 
222 static int __init openrisc_device_probe(void)
223 {
224 	of_platform_populate(NULL, NULL, NULL, NULL);
225 
226 	return 0;
227 }
228 
229 device_initcall(openrisc_device_probe);
230 
231 static inline unsigned long extract_value_bits(unsigned long reg,
232 					       short bit_nr, short width)
233 {
234 	return (reg >> bit_nr) & (0 << width);
235 }
236 
237 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
238 {
239 	while (!(mask & 0x1)) {
240 		reg = reg >> 1;
241 		mask = mask >> 1;
242 	}
243 	return mask & reg;
244 }
245 
246 void __init detect_unit_config(unsigned long upr, unsigned long mask,
247 			       char *text, void (*func) (void))
248 {
249 	if (text != NULL)
250 		printk("%s", text);
251 
252 	if (upr & mask) {
253 		if (func != NULL)
254 			func();
255 		else
256 			printk("present\n");
257 	} else
258 		printk("not present\n");
259 }
260 
261 /*
262  * calibrate_delay
263  *
264  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
265  * from the clock frequency passed in via the device tree
266  *
267  */
268 
269 void calibrate_delay(void)
270 {
271 	const int *val;
272 	struct device_node *cpu = NULL;
273 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
274 	val = of_get_property(cpu, "clock-frequency", NULL);
275 	if (!val)
276 		panic("no cpu 'clock-frequency' parameter in device tree");
277 	loops_per_jiffy = *val / HZ;
278 	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
279 		loops_per_jiffy / (500000 / HZ),
280 		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
281 }
282 
283 void __init setup_arch(char **cmdline_p)
284 {
285 	unsigned long max_low_pfn;
286 
287 	unflatten_and_copy_device_tree();
288 
289 	setup_cpuinfo();
290 
291 	/* process 1's initial memory region is the kernel code/data */
292 	init_mm.start_code = (unsigned long)_stext;
293 	init_mm.end_code = (unsigned long)_etext;
294 	init_mm.end_data = (unsigned long)_edata;
295 	init_mm.brk = (unsigned long)_end;
296 
297 #ifdef CONFIG_BLK_DEV_INITRD
298 	initrd_start = (unsigned long)&__initrd_start;
299 	initrd_end = (unsigned long)&__initrd_end;
300 	if (initrd_start == initrd_end) {
301 		initrd_start = 0;
302 		initrd_end = 0;
303 	}
304 	initrd_below_start_ok = 1;
305 #endif
306 
307 	/* setup bootmem allocator */
308 	max_low_pfn = setup_memory();
309 
310 	/* paging_init() sets up the MMU and marks all pages as reserved */
311 	paging_init();
312 
313 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
314 	if (!conswitchp)
315 		conswitchp = &dummy_con;
316 #endif
317 
318 	*cmdline_p = boot_command_line;
319 
320 	printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
321 }
322 
323 static int show_cpuinfo(struct seq_file *m, void *v)
324 {
325 	unsigned long vr;
326 	int version, revision;
327 
328 	vr = mfspr(SPR_VR);
329 	version = (vr & SPR_VR_VER) >> 24;
330 	revision = vr & SPR_VR_REV;
331 
332 	seq_printf(m,
333 		   "cpu\t\t: OpenRISC-%x\n"
334 		   "revision\t: %d\n"
335 		   "frequency\t: %ld\n"
336 		   "dcache size\t: %d bytes\n"
337 		   "dcache block size\t: %d bytes\n"
338 		   "icache size\t: %d bytes\n"
339 		   "icache block size\t: %d bytes\n"
340 		   "immu\t\t: %d entries, %lu ways\n"
341 		   "dmmu\t\t: %d entries, %lu ways\n"
342 		   "bogomips\t: %lu.%02lu\n",
343 		   version,
344 		   revision,
345 		   loops_per_jiffy * HZ,
346 		   cpuinfo.dcache_size,
347 		   cpuinfo.dcache_block_size,
348 		   cpuinfo.icache_size,
349 		   cpuinfo.icache_block_size,
350 		   1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
351 		   1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
352 		   1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
353 		   1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
354 		   (loops_per_jiffy * HZ) / 500000,
355 		   ((loops_per_jiffy * HZ) / 5000) % 100);
356 
357 	return 0;
358 }
359 
360 static void *c_start(struct seq_file *m, loff_t * pos)
361 {
362 	/* We only have one CPU... */
363 	return *pos < 1 ? (void *)1 : NULL;
364 }
365 
366 static void *c_next(struct seq_file *m, void *v, loff_t * pos)
367 {
368 	++*pos;
369 	return NULL;
370 }
371 
372 static void c_stop(struct seq_file *m, void *v)
373 {
374 }
375 
376 const struct seq_operations cpuinfo_op = {
377 	.start = c_start,
378 	.next = c_next,
379 	.stop = c_stop,
380 	.show = show_cpuinfo,
381 };
382