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
54static 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
107struct cpuinfo cpuinfo;
108
109static 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
165void __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
211void __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
222static int __init openrisc_device_probe(void)
223{
224	of_platform_populate(NULL, NULL, NULL, NULL);
225
226	return 0;
227}
228
229device_initcall(openrisc_device_probe);
230
231static 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
237static 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
246void __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
269void 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
283void __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
323static 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
360static 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
366static void *c_next(struct seq_file *m, void *v, loff_t * pos)
367{
368	++*pos;
369	return NULL;
370}
371
372static void c_stop(struct seq_file *m, void *v)
373{
374}
375
376const struct seq_operations cpuinfo_op = {
377	.start = c_start,
378	.next = c_next,
379	.stop = c_stop,
380	.show = show_cpuinfo,
381};
382