xref: /openbmc/linux/arch/openrisc/kernel/setup.c (revision 08157984)
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 char __initdata cmd_line[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
54 
55 static unsigned long __init setup_memory(void)
56 {
57 	unsigned long bootmap_size;
58 	unsigned long ram_start_pfn;
59 	unsigned long free_ram_start_pfn;
60 	unsigned long ram_end_pfn;
61 	phys_addr_t memory_start, memory_end;
62 	struct memblock_region *region;
63 
64 	memory_end = memory_start = 0;
65 
66 	/* Find main memory where is the kernel */
67 	for_each_memblock(memory, region) {
68 		memory_start = region->base;
69 		memory_end = region->base + region->size;
70 		printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
71 		       memory_start, memory_end);
72 	}
73 
74 	if (!memory_end) {
75 		panic("No memory!");
76 	}
77 
78 	ram_start_pfn = PFN_UP(memory_start);
79 	/* free_ram_start_pfn is first page after kernel */
80 	free_ram_start_pfn = PFN_UP(__pa(&_end));
81 	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
82 
83 	max_pfn = ram_end_pfn;
84 
85 	/*
86 	 * initialize the boot-time allocator (with low memory only).
87 	 *
88 	 * This makes the memory from the end of the kernel to the end of
89 	 * RAM usable.
90 	 * init_bootmem sets the global values min_low_pfn, max_low_pfn.
91 	 */
92 	bootmap_size = init_bootmem(free_ram_start_pfn,
93 				    ram_end_pfn - ram_start_pfn);
94 	free_bootmem(PFN_PHYS(free_ram_start_pfn),
95 		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
96 	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
97 			BOOTMEM_DEFAULT);
98 
99 	for_each_memblock(reserved, region) {
100 		printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
101 		       (u32) region->base, (u32) region->size);
102 		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
103 	}
104 
105 	return ram_end_pfn;
106 }
107 
108 struct cpuinfo cpuinfo;
109 
110 static void print_cpuinfo(void)
111 {
112 	unsigned long upr = mfspr(SPR_UPR);
113 	unsigned long vr = mfspr(SPR_VR);
114 	unsigned int version;
115 	unsigned int revision;
116 
117 	version = (vr & SPR_VR_VER) >> 24;
118 	revision = (vr & SPR_VR_REV);
119 
120 	printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
121 	       version, revision, cpuinfo.clock_frequency / 1000000);
122 
123 	if (!(upr & SPR_UPR_UP)) {
124 		printk(KERN_INFO
125 		       "-- no UPR register... unable to detect configuration\n");
126 		return;
127 	}
128 
129 	if (upr & SPR_UPR_DCP)
130 		printk(KERN_INFO
131 		       "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
132 		       cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
133 	else
134 		printk(KERN_INFO "-- dcache disabled\n");
135 	if (upr & SPR_UPR_ICP)
136 		printk(KERN_INFO
137 		       "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
138 		       cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
139 	else
140 		printk(KERN_INFO "-- icache disabled\n");
141 
142 	if (upr & SPR_UPR_DMP)
143 		printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
144 		       1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
145 		       1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
146 	if (upr & SPR_UPR_IMP)
147 		printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
148 		       1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
149 		       1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
150 
151 	printk(KERN_INFO "-- additional features:\n");
152 	if (upr & SPR_UPR_DUP)
153 		printk(KERN_INFO "-- debug unit\n");
154 	if (upr & SPR_UPR_PCUP)
155 		printk(KERN_INFO "-- performance counters\n");
156 	if (upr & SPR_UPR_PMP)
157 		printk(KERN_INFO "-- power management\n");
158 	if (upr & SPR_UPR_PICP)
159 		printk(KERN_INFO "-- PIC\n");
160 	if (upr & SPR_UPR_TTP)
161 		printk(KERN_INFO "-- timer\n");
162 	if (upr & SPR_UPR_CUP)
163 		printk(KERN_INFO "-- custom unit(s)\n");
164 }
165 
166 void __init setup_cpuinfo(void)
167 {
168 	struct device_node *cpu;
169 	unsigned long iccfgr, dccfgr;
170 	unsigned long cache_set_size, cache_ways;
171 
172 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
173 	if (!cpu)
174 		panic("No compatible CPU found in device tree...\n");
175 
176 	iccfgr = mfspr(SPR_ICCFGR);
177 	cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
178 	cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
179 	cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
180 	cpuinfo.icache_size =
181 	    cache_set_size * cache_ways * cpuinfo.icache_block_size;
182 
183 	dccfgr = mfspr(SPR_DCCFGR);
184 	cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
185 	cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
186 	cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
187 	cpuinfo.dcache_size =
188 	    cache_set_size * cache_ways * cpuinfo.dcache_block_size;
189 
190 	if (of_property_read_u32(cpu, "clock-frequency",
191 				 &cpuinfo.clock_frequency)) {
192 		printk(KERN_WARNING
193 		       "Device tree missing CPU 'clock-frequency' parameter."
194 		       "Assuming frequency 25MHZ"
195 		       "This is probably not what you want.");
196 	}
197 
198 	of_node_put(cpu);
199 
200 	print_cpuinfo();
201 }
202 
203 /**
204  * or32_early_setup
205  *
206  * Handles the pointer to the device tree that this kernel is to use
207  * for establishing the available platform devices.
208  *
209  * Falls back on built-in device tree in case null pointer is passed.
210  */
211 
212 void __init or32_early_setup(unsigned int fdt)
213 {
214 	if (fdt) {
215 		early_init_devtree((void*) fdt);
216 		printk(KERN_INFO "FDT at 0x%08x\n", fdt);
217 	} else {
218 		early_init_devtree(__dtb_start);
219 		printk(KERN_INFO "Compiled-in FDT at %p\n", __dtb_start);
220 	}
221 }
222 
223 static int __init openrisc_device_probe(void)
224 {
225 	of_platform_populate(NULL, NULL, NULL, NULL);
226 
227 	return 0;
228 }
229 
230 device_initcall(openrisc_device_probe);
231 
232 static inline unsigned long extract_value_bits(unsigned long reg,
233 					       short bit_nr, short width)
234 {
235 	return (reg >> bit_nr) & (0 << width);
236 }
237 
238 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
239 {
240 	while (!(mask & 0x1)) {
241 		reg = reg >> 1;
242 		mask = mask >> 1;
243 	}
244 	return mask & reg;
245 }
246 
247 void __init detect_unit_config(unsigned long upr, unsigned long mask,
248 			       char *text, void (*func) (void))
249 {
250 	if (text != NULL)
251 		printk("%s", text);
252 
253 	if (upr & mask) {
254 		if (func != NULL)
255 			func();
256 		else
257 			printk("present\n");
258 	} else
259 		printk("not present\n");
260 }
261 
262 /*
263  * calibrate_delay
264  *
265  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
266  * from the clock frequency passed in via the device tree
267  *
268  */
269 
270 void __cpuinit calibrate_delay(void)
271 {
272 	const int *val;
273 	struct device_node *cpu = NULL;
274 	cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
275 	val = of_get_property(cpu, "clock-frequency", NULL);
276 	if (!val)
277 		panic("no cpu 'clock-frequency' parameter in device tree");
278 	loops_per_jiffy = *val / HZ;
279 	pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
280 		loops_per_jiffy / (500000 / HZ),
281 		(loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
282 }
283 
284 void __init setup_arch(char **cmdline_p)
285 {
286 	unsigned long max_low_pfn;
287 
288 	unflatten_device_tree();
289 
290 	setup_cpuinfo();
291 
292 	/* process 1's initial memory region is the kernel code/data */
293 	init_mm.start_code = (unsigned long)&_stext;
294 	init_mm.end_code = (unsigned long)&_etext;
295 	init_mm.end_data = (unsigned long)&_edata;
296 	init_mm.brk = (unsigned long)&_end;
297 
298 #ifdef CONFIG_BLK_DEV_INITRD
299 	initrd_start = (unsigned long)&__initrd_start;
300 	initrd_end = (unsigned long)&__initrd_end;
301 	if (initrd_start == initrd_end) {
302 		initrd_start = 0;
303 		initrd_end = 0;
304 	}
305 	initrd_below_start_ok = 1;
306 #endif
307 
308 	/* setup bootmem allocator */
309 	max_low_pfn = setup_memory();
310 
311 	/* paging_init() sets up the MMU and marks all pages as reserved */
312 	paging_init();
313 
314 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
315 	if (!conswitchp)
316 		conswitchp = &dummy_con;
317 #endif
318 
319 	*cmdline_p = cmd_line;
320 
321 	printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
322 }
323 
324 static int show_cpuinfo(struct seq_file *m, void *v)
325 {
326 	unsigned long vr;
327 	int version, revision;
328 
329 	vr = mfspr(SPR_VR);
330 	version = (vr & SPR_VR_VER) >> 24;
331 	revision = vr & SPR_VR_REV;
332 
333 	return seq_printf(m,
334 			  "cpu\t\t: OpenRISC-%x\n"
335 			  "revision\t: %d\n"
336 			  "frequency\t: %ld\n"
337 			  "dcache size\t: %d bytes\n"
338 			  "dcache block size\t: %d bytes\n"
339 			  "icache size\t: %d bytes\n"
340 			  "icache block size\t: %d bytes\n"
341 			  "immu\t\t: %d entries, %lu ways\n"
342 			  "dmmu\t\t: %d entries, %lu ways\n"
343 			  "bogomips\t: %lu.%02lu\n",
344 			  version,
345 			  revision,
346 			  loops_per_jiffy * HZ,
347 			  cpuinfo.dcache_size,
348 			  cpuinfo.dcache_block_size,
349 			  cpuinfo.icache_size,
350 			  cpuinfo.icache_block_size,
351 			  1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
352 			  1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
353 			  1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
354 			  1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
355 			  (loops_per_jiffy * HZ) / 500000,
356 			  ((loops_per_jiffy * HZ) / 5000) % 100);
357 }
358 
359 static void *c_start(struct seq_file *m, loff_t * pos)
360 {
361 	/* We only have one CPU... */
362 	return *pos < 1 ? (void *)1 : NULL;
363 }
364 
365 static void *c_next(struct seq_file *m, void *v, loff_t * pos)
366 {
367 	++*pos;
368 	return NULL;
369 }
370 
371 static void c_stop(struct seq_file *m, void *v)
372 {
373 }
374 
375 const struct seq_operations cpuinfo_op = {
376 	.start = c_start,
377 	.next = c_next,
378 	.stop = c_stop,
379 	.show = show_cpuinfo,
380 };
381