xref: /linux/arch/openrisc/kernel/setup.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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/system.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 char __initdata cmd_line[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
55 
56 static unsigned long __init setup_memory(void)
57 {
58 	unsigned long bootmap_size;
59 	unsigned long ram_start_pfn;
60 	unsigned long free_ram_start_pfn;
61 	unsigned long ram_end_pfn;
62 	phys_addr_t memory_start, memory_end;
63 	struct memblock_region *region;
64 
65 	memory_end = memory_start = 0;
66 
67 	/* Find main memory where is the kernel */
68 	for_each_memblock(memory, region) {
69 		memory_start = region->base;
70 		memory_end = region->base + region->size;
71 		printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
72 		       memory_start, memory_end);
73 	}
74 
75 	if (!memory_end) {
76 		panic("No memory!");
77 	}
78 
79 	ram_start_pfn = PFN_UP(memory_start);
80 	/* free_ram_start_pfn is first page after kernel */
81 	free_ram_start_pfn = PFN_UP(__pa(&_end));
82 	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
83 
84 	max_pfn = ram_end_pfn;
85 
86 	/*
87 	 * initialize the boot-time allocator (with low memory only).
88 	 *
89 	 * This makes the memory from the end of the kernel to the end of
90 	 * RAM usable.
91 	 * init_bootmem sets the global values min_low_pfn, max_low_pfn.
92 	 */
93 	bootmap_size = init_bootmem(free_ram_start_pfn,
94 				    ram_end_pfn - ram_start_pfn);
95 	free_bootmem(PFN_PHYS(free_ram_start_pfn),
96 		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
97 	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
98 			BOOTMEM_DEFAULT);
99 
100 	for_each_memblock(reserved, region) {
101 		printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
102 		       (u32) region->base, (u32) region->size);
103 		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
104 	}
105 
106 	return ram_end_pfn;
107 }
108 
109 struct cpuinfo cpuinfo;
110 
111 static void print_cpuinfo(void)
112 {
113 	unsigned long upr = mfspr(SPR_UPR);
114 	unsigned long vr = mfspr(SPR_VR);
115 	unsigned int version;
116 	unsigned int revision;
117 
118 	version = (vr & SPR_VR_VER) >> 24;
119 	revision = (vr & SPR_VR_REV);
120 
121 	printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
122 	       version, revision, cpuinfo.clock_frequency / 1000000);
123 
124 	if (!(upr & SPR_UPR_UP)) {
125 		printk(KERN_INFO
126 		       "-- no UPR register... unable to detect configuration\n");
127 		return;
128 	}
129 
130 	if (upr & SPR_UPR_DCP)
131 		printk(KERN_INFO
132 		       "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
133 		       cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
134 	else
135 		printk(KERN_INFO "-- dcache disabled\n");
136 	if (upr & SPR_UPR_ICP)
137 		printk(KERN_INFO
138 		       "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
139 		       cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
140 	else
141 		printk(KERN_INFO "-- icache disabled\n");
142 
143 	if (upr & SPR_UPR_DMP)
144 		printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
145 		       1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
146 		       1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
147 	if (upr & SPR_UPR_IMP)
148 		printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
149 		       1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
150 		       1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
151 
152 	printk(KERN_INFO "-- additional features:\n");
153 	if (upr & SPR_UPR_DUP)
154 		printk(KERN_INFO "-- debug unit\n");
155 	if (upr & SPR_UPR_PCUP)
156 		printk(KERN_INFO "-- performance counters\n");
157 	if (upr & SPR_UPR_PMP)
158 		printk(KERN_INFO "-- power management\n");
159 	if (upr & SPR_UPR_PICP)
160 		printk(KERN_INFO "-- PIC\n");
161 	if (upr & SPR_UPR_TTP)
162 		printk(KERN_INFO "-- timer\n");
163 	if (upr & SPR_UPR_CUP)
164 		printk(KERN_INFO "-- custom unit(s)\n");
165 }
166 
167 void __init setup_cpuinfo(void)
168 {
169 	struct device_node *cpu;
170 	unsigned long iccfgr, dccfgr;
171 	unsigned long cache_set_size, cache_ways;
172 
173 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
174 	if (!cpu)
175 		panic("No compatible CPU found in device tree...\n");
176 
177 	iccfgr = mfspr(SPR_ICCFGR);
178 	cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
179 	cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
180 	cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
181 	cpuinfo.icache_size =
182 	    cache_set_size * cache_ways * cpuinfo.icache_block_size;
183 
184 	dccfgr = mfspr(SPR_DCCFGR);
185 	cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
186 	cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
187 	cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
188 	cpuinfo.dcache_size =
189 	    cache_set_size * cache_ways * cpuinfo.dcache_block_size;
190 
191 	if (of_property_read_u32(cpu, "clock-frequency",
192 				 &cpuinfo.clock_frequency)) {
193 		printk(KERN_WARNING
194 		       "Device tree missing CPU 'clock-frequency' parameter."
195 		       "Assuming frequency 25MHZ"
196 		       "This is probably not what you want.");
197 	}
198 
199 	of_node_put(cpu);
200 
201 	print_cpuinfo();
202 }
203 
204 /**
205  * or32_early_setup
206  *
207  * Handles the pointer to the device tree that this kernel is to use
208  * for establishing the available platform devices.
209  *
210  * For now, this is limited to using the built-in device tree.  In the future,
211  * it is intended that this function will take a pointer to the device tree
212  * that is potentially built-in, but potentially also passed in by the
213  * bootloader, or discovered by some equally clever means...
214  */
215 
216 void __init or32_early_setup(void)
217 {
218 
219 	early_init_devtree(__dtb_start);
220 
221 	printk(KERN_INFO "Compiled-in FDT at 0x%p\n", __dtb_start);
222 }
223 
224 static int __init openrisc_device_probe(void)
225 {
226 	of_platform_populate(NULL, NULL, NULL, NULL);
227 
228 	return 0;
229 }
230 
231 device_initcall(openrisc_device_probe);
232 
233 static inline unsigned long extract_value_bits(unsigned long reg,
234 					       short bit_nr, short width)
235 {
236 	return (reg >> bit_nr) & (0 << width);
237 }
238 
239 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
240 {
241 	while (!(mask & 0x1)) {
242 		reg = reg >> 1;
243 		mask = mask >> 1;
244 	}
245 	return mask & reg;
246 }
247 
248 void __init detect_unit_config(unsigned long upr, unsigned long mask,
249 			       char *text, void (*func) (void))
250 {
251 	if (text != NULL)
252 		printk("%s", text);
253 
254 	if (upr & mask) {
255 		if (func != NULL)
256 			func();
257 		else
258 			printk("present\n");
259 	} else
260 		printk("not present\n");
261 }
262 
263 /*
264  * calibrate_delay
265  *
266  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
267  * from the clock frequency passed in via the device tree
268  *
269  */
270 
271 void __cpuinit calibrate_delay(void)
272 {
273 	const int *val;
274 	struct device_node *cpu = NULL;
275 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
276 	val = of_get_property(cpu, "clock-frequency", NULL);
277 	if (!val)
278 		panic("no cpu 'clock-frequency' parameter in device tree");
279 	loops_per_jiffy = *val / HZ;
280 	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
281 		loops_per_jiffy / (500000 / HZ),
282 		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
283 }
284 
285 void __init setup_arch(char **cmdline_p)
286 {
287 	unsigned long max_low_pfn;
288 
289 	unflatten_device_tree();
290 
291 	setup_cpuinfo();
292 
293 	/* process 1's initial memory region is the kernel code/data */
294 	init_mm.start_code = (unsigned long)&_stext;
295 	init_mm.end_code = (unsigned long)&_etext;
296 	init_mm.end_data = (unsigned long)&_edata;
297 	init_mm.brk = (unsigned long)&_end;
298 
299 #ifdef CONFIG_BLK_DEV_INITRD
300 	initrd_start = (unsigned long)&__initrd_start;
301 	initrd_end = (unsigned long)&__initrd_end;
302 	if (initrd_start == initrd_end) {
303 		initrd_start = 0;
304 		initrd_end = 0;
305 	}
306 	initrd_below_start_ok = 1;
307 #endif
308 
309 	/* setup bootmem allocator */
310 	max_low_pfn = setup_memory();
311 
312 	/* paging_init() sets up the MMU and marks all pages as reserved */
313 	paging_init();
314 
315 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
316 	if (!conswitchp)
317 		conswitchp = &dummy_con;
318 #endif
319 
320 	*cmdline_p = cmd_line;
321 
322 	printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
323 }
324 
325 static int show_cpuinfo(struct seq_file *m, void *v)
326 {
327 	unsigned long vr;
328 	int version, revision;
329 
330 	vr = mfspr(SPR_VR);
331 	version = (vr & SPR_VR_VER) >> 24;
332 	revision = vr & SPR_VR_REV;
333 
334 	return seq_printf(m,
335 			  "cpu\t\t: OpenRISC-%x\n"
336 			  "revision\t: %d\n"
337 			  "frequency\t: %ld\n"
338 			  "dcache size\t: %d bytes\n"
339 			  "dcache block size\t: %d bytes\n"
340 			  "icache size\t: %d bytes\n"
341 			  "icache block size\t: %d bytes\n"
342 			  "immu\t\t: %d entries, %lu ways\n"
343 			  "dmmu\t\t: %d entries, %lu ways\n"
344 			  "bogomips\t: %lu.%02lu\n",
345 			  version,
346 			  revision,
347 			  loops_per_jiffy * HZ,
348 			  cpuinfo.dcache_size,
349 			  cpuinfo.dcache_block_size,
350 			  cpuinfo.icache_size,
351 			  cpuinfo.icache_block_size,
352 			  1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
353 			  1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
354 			  1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
355 			  1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
356 			  (loops_per_jiffy * HZ) / 500000,
357 			  ((loops_per_jiffy * HZ) / 5000) % 100);
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