Blackfin arch: When icache is off, make sure people know it
[linux-2.6] / arch / sparc / kernel / sun4m_smp.c
1 /* sun4m_smp.c: Sparc SUN4M SMP support.
2  *
3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
4  */
5
6 #include <asm/head.h>
7
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/threads.h>
11 #include <linux/smp.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel_stat.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/mm.h>
17 #include <linux/swap.h>
18 #include <linux/profile.h>
19 #include <linux/delay.h>
20
21 #include <asm/cacheflush.h>
22 #include <asm/tlbflush.h>
23 #include <asm/irq_regs.h>
24
25 #include <asm/ptrace.h>
26 #include <asm/atomic.h>
27
28 #include <asm/irq.h>
29 #include <asm/page.h>
30 #include <asm/pgalloc.h>
31 #include <asm/pgtable.h>
32 #include <asm/oplib.h>
33 #include <asm/cpudata.h>
34
35 #include "irq.h"
36
37 #define IRQ_CROSS_CALL          15
38
39 extern ctxd_t *srmmu_ctx_table_phys;
40
41 extern volatile unsigned long cpu_callin_map[NR_CPUS];
42 extern unsigned char boot_cpu_id;
43
44 extern cpumask_t smp_commenced_mask;
45
46 extern int __smp4m_processor_id(void);
47
48 /*#define SMP_DEBUG*/
49
50 #ifdef SMP_DEBUG
51 #define SMP_PRINTK(x)   printk x
52 #else
53 #define SMP_PRINTK(x)
54 #endif
55
56 static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
57 {
58         __asm__ __volatile__("swap [%1], %0\n\t" :
59                              "=&r" (val), "=&r" (ptr) :
60                              "0" (val), "1" (ptr));
61         return val;
62 }
63
64 static void smp_setup_percpu_timer(void);
65 extern void cpu_probe(void);
66
67 void __cpuinit smp4m_callin(void)
68 {
69         int cpuid = hard_smp_processor_id();
70
71         local_flush_cache_all();
72         local_flush_tlb_all();
73
74         /* Get our local ticker going. */
75         smp_setup_percpu_timer();
76
77         calibrate_delay();
78         smp_store_cpu_info(cpuid);
79
80         local_flush_cache_all();
81         local_flush_tlb_all();
82
83         /*
84          * Unblock the master CPU _only_ when the scheduler state
85          * of all secondary CPUs will be up-to-date, so after
86          * the SMP initialization the master will be just allowed
87          * to call the scheduler code.
88          */
89         /* Allow master to continue. */
90         swap(&cpu_callin_map[cpuid], 1);
91
92         /* XXX: What's up with all the flushes? */
93         local_flush_cache_all();
94         local_flush_tlb_all();
95         
96         cpu_probe();
97
98         /* Fix idle thread fields. */
99         __asm__ __volatile__("ld [%0], %%g6\n\t"
100                              : : "r" (&current_set[cpuid])
101                              : "memory" /* paranoid */);
102
103         /* Attach to the address space of init_task. */
104         atomic_inc(&init_mm.mm_count);
105         current->active_mm = &init_mm;
106
107         while (!cpu_isset(cpuid, smp_commenced_mask))
108                 mb();
109
110         local_irq_enable();
111
112         cpu_set(cpuid, cpu_online_map);
113 }
114
115 /*
116  *      Cycle through the processors asking the PROM to start each one.
117  */
118  
119 extern struct linux_prom_registers smp_penguin_ctable;
120 extern unsigned long trapbase_cpu1[];
121 extern unsigned long trapbase_cpu2[];
122 extern unsigned long trapbase_cpu3[];
123
124 void __init smp4m_boot_cpus(void)
125 {
126         smp_setup_percpu_timer();
127         local_flush_cache_all();
128 }
129
130 int __cpuinit smp4m_boot_one_cpu(int i)
131 {
132         extern unsigned long sun4m_cpu_startup;
133         unsigned long *entry = &sun4m_cpu_startup;
134         struct task_struct *p;
135         int timeout;
136         int cpu_node;
137
138         cpu_find_by_mid(i, &cpu_node);
139
140         /* Cook up an idler for this guy. */
141         p = fork_idle(i);
142         current_set[i] = task_thread_info(p);
143         /* See trampoline.S for details... */
144         entry += ((i-1) * 3);
145
146         /*
147          * Initialize the contexts table
148          * Since the call to prom_startcpu() trashes the structure,
149          * we need to re-initialize it for each cpu
150          */
151         smp_penguin_ctable.which_io = 0;
152         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
153         smp_penguin_ctable.reg_size = 0;
154
155         /* whirrr, whirrr, whirrrrrrrrr... */
156         printk("Starting CPU %d at %p\n", i, entry);
157         local_flush_cache_all();
158         prom_startcpu(cpu_node,
159                       &smp_penguin_ctable, 0, (char *)entry);
160
161         /* wheee... it's going... */
162         for(timeout = 0; timeout < 10000; timeout++) {
163                 if(cpu_callin_map[i])
164                         break;
165                 udelay(200);
166         }
167
168         if (!(cpu_callin_map[i])) {
169                 printk("Processor %d is stuck.\n", i);
170                 return -ENODEV;
171         }
172
173         local_flush_cache_all();
174         return 0;
175 }
176
177 void __init smp4m_smp_done(void)
178 {
179         int i, first;
180         int *prev;
181
182         /* setup cpu list for irq rotation */
183         first = 0;
184         prev = &first;
185         for (i = 0; i < NR_CPUS; i++) {
186                 if (cpu_online(i)) {
187                         *prev = i;
188                         prev = &cpu_data(i).next;
189                 }
190         }
191         *prev = first;
192         local_flush_cache_all();
193
194         /* Free unneeded trap tables */
195         if (!cpu_isset(1, cpu_present_map)) {
196                 ClearPageReserved(virt_to_page(trapbase_cpu1));
197                 init_page_count(virt_to_page(trapbase_cpu1));
198                 free_page((unsigned long)trapbase_cpu1);
199                 totalram_pages++;
200                 num_physpages++;
201         }
202         if (!cpu_isset(2, cpu_present_map)) {
203                 ClearPageReserved(virt_to_page(trapbase_cpu2));
204                 init_page_count(virt_to_page(trapbase_cpu2));
205                 free_page((unsigned long)trapbase_cpu2);
206                 totalram_pages++;
207                 num_physpages++;
208         }
209         if (!cpu_isset(3, cpu_present_map)) {
210                 ClearPageReserved(virt_to_page(trapbase_cpu3));
211                 init_page_count(virt_to_page(trapbase_cpu3));
212                 free_page((unsigned long)trapbase_cpu3);
213                 totalram_pages++;
214                 num_physpages++;
215         }
216
217         /* Ok, they are spinning and ready to go. */
218 }
219
220 /* At each hardware IRQ, we get this called to forward IRQ reception
221  * to the next processor.  The caller must disable the IRQ level being
222  * serviced globally so that there are no double interrupts received.
223  *
224  * XXX See sparc64 irq.c.
225  */
226 void smp4m_irq_rotate(int cpu)
227 {
228         int next = cpu_data(cpu).next;
229         if (next != cpu)
230                 set_irq_udt(next);
231 }
232
233 static struct smp_funcall {
234         smpfunc_t func;
235         unsigned long arg1;
236         unsigned long arg2;
237         unsigned long arg3;
238         unsigned long arg4;
239         unsigned long arg5;
240         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
241         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
242 } ccall_info;
243
244 static DEFINE_SPINLOCK(cross_call_lock);
245
246 /* Cross calls must be serialized, at least currently. */
247 void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
248                     unsigned long arg3, unsigned long arg4, unsigned long arg5)
249 {
250                 register int ncpus = SUN4M_NCPUS;
251                 unsigned long flags;
252
253                 spin_lock_irqsave(&cross_call_lock, flags);
254
255                 /* Init function glue. */
256                 ccall_info.func = func;
257                 ccall_info.arg1 = arg1;
258                 ccall_info.arg2 = arg2;
259                 ccall_info.arg3 = arg3;
260                 ccall_info.arg4 = arg4;
261                 ccall_info.arg5 = arg5;
262
263                 /* Init receive/complete mapping, plus fire the IPI's off. */
264                 {
265                         cpumask_t mask = cpu_online_map;
266                         register int i;
267
268                         cpu_clear(smp_processor_id(), mask);
269                         for(i = 0; i < ncpus; i++) {
270                                 if (cpu_isset(i, mask)) {
271                                         ccall_info.processors_in[i] = 0;
272                                         ccall_info.processors_out[i] = 0;
273                                         set_cpu_int(i, IRQ_CROSS_CALL);
274                                 } else {
275                                         ccall_info.processors_in[i] = 1;
276                                         ccall_info.processors_out[i] = 1;
277                                 }
278                         }
279                 }
280
281                 {
282                         register int i;
283
284                         i = 0;
285                         do {
286                                 while(!ccall_info.processors_in[i])
287                                         barrier();
288                         } while(++i < ncpus);
289
290                         i = 0;
291                         do {
292                                 while(!ccall_info.processors_out[i])
293                                         barrier();
294                         } while(++i < ncpus);
295                 }
296
297                 spin_unlock_irqrestore(&cross_call_lock, flags);
298 }
299
300 /* Running cross calls. */
301 void smp4m_cross_call_irq(void)
302 {
303         int i = smp_processor_id();
304
305         ccall_info.processors_in[i] = 1;
306         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
307                         ccall_info.arg4, ccall_info.arg5);
308         ccall_info.processors_out[i] = 1;
309 }
310
311 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
312 {
313         struct pt_regs *old_regs;
314         int cpu = smp_processor_id();
315
316         old_regs = set_irq_regs(regs);
317
318         clear_profile_irq(cpu);
319
320         profile_tick(CPU_PROFILING);
321
322         if(!--prof_counter(cpu)) {
323                 int user = user_mode(regs);
324
325                 irq_enter();
326                 update_process_times(user);
327                 irq_exit();
328
329                 prof_counter(cpu) = prof_multiplier(cpu);
330         }
331         set_irq_regs(old_regs);
332 }
333
334 extern unsigned int lvl14_resolution;
335
336 static void __init smp_setup_percpu_timer(void)
337 {
338         int cpu = smp_processor_id();
339
340         prof_counter(cpu) = prof_multiplier(cpu) = 1;
341         load_profile_irq(cpu, lvl14_resolution);
342
343         if(cpu == boot_cpu_id)
344                 enable_pil_irq(14);
345 }
346
347 void __init smp4m_blackbox_id(unsigned *addr)
348 {
349         int rd = *addr & 0x3e000000;
350         int rs1 = rd >> 11;
351         
352         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
353         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
354         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
355 }
356
357 void __init smp4m_blackbox_current(unsigned *addr)
358 {
359         int rd = *addr & 0x3e000000;
360         int rs1 = rd >> 11;
361         
362         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
363         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
364         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
365 }
366
367 void __init sun4m_init_smp(void)
368 {
369         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
370         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
371         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
372         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
373 }