1 /*
2  * include/asm-parisc/processor.h
3  *
4  * Copyright (C) 1994 Linus Torvalds
5  * Copyright (C) 2001 Grant Grundler
6  */
7 
8 #ifndef __ASM_PARISC_PROCESSOR_H
9 #define __ASM_PARISC_PROCESSOR_H
10 
11 #ifndef __ASSEMBLY__
12 #include <linux/threads.h>
13 
14 #include <asm/prefetch.h>
15 #include <asm/hardware.h>
16 #include <asm/pdc.h>
17 #include <asm/ptrace.h>
18 #include <asm/types.h>
19 #include <asm/percpu.h>
20 
21 #endif /* __ASSEMBLY__ */
22 
23 /*
24  * Default implementation of macro that returns current
25  * instruction pointer ("program counter").
26  */
27 #ifdef CONFIG_PA20
28 #define current_ia(x)	__asm__("mfia %0" : "=r"(x))
29 #else /* mfia added in pa2.0 */
30 #define current_ia(x)	__asm__("blr 0,%0\n\tnop" : "=r"(x))
31 #endif
32 #define current_text_addr() ({ void *pc; current_ia(pc); pc; })
33 
34 #define TASK_SIZE_OF(tsk)       ((tsk)->thread.task_size)
35 #define TASK_SIZE	        TASK_SIZE_OF(current)
36 #define TASK_UNMAPPED_BASE      (current->thread.map_base)
37 
38 #define DEFAULT_TASK_SIZE32	(0xFFF00000UL)
39 #define DEFAULT_MAP_BASE32	(0x40000000UL)
40 
41 #ifdef CONFIG_64BIT
42 #define DEFAULT_TASK_SIZE       (MAX_ADDRESS-0xf000000)
43 #define DEFAULT_MAP_BASE        (0x200000000UL)
44 #else
45 #define DEFAULT_TASK_SIZE	DEFAULT_TASK_SIZE32
46 #define DEFAULT_MAP_BASE	DEFAULT_MAP_BASE32
47 #endif
48 
49 #ifdef __KERNEL__
50 
51 /* XXX: STACK_TOP actually should be STACK_BOTTOM for parisc.
52  * prumpf */
53 
54 #define STACK_TOP	TASK_SIZE
55 #define STACK_TOP_MAX	DEFAULT_TASK_SIZE
56 
57 #endif
58 
59 #ifndef __ASSEMBLY__
60 
61 /*
62  * IRQ STACK - used for irq handler
63  */
64 #ifdef __KERNEL__
65 
66 #include <linux/spinlock_types.h>
67 
68 #define IRQ_STACK_SIZE      (4096 << 2) /* 16k irq stack size */
69 
70 union irq_stack_union {
71 	unsigned long stack[IRQ_STACK_SIZE/sizeof(unsigned long)];
72 	raw_spinlock_t lock;
73 };
74 
75 DECLARE_PER_CPU(union irq_stack_union, irq_stack_union);
76 
77 void call_on_stack(unsigned long p1, void *func, unsigned long new_stack);
78 
79 #endif /* __KERNEL__ */
80 
81 /*
82  * Data detected about CPUs at boot time which is the same for all CPU's.
83  * HP boxes are SMP - ie identical processors.
84  *
85  * FIXME: some CPU rev info may be processor specific...
86  */
87 struct system_cpuinfo_parisc {
88 	unsigned int	cpu_count;
89 	unsigned int	cpu_hz;
90 	unsigned int	hversion;
91 	unsigned int	sversion;
92 	enum cpu_type	cpu_type;
93 
94 	struct {
95 		struct pdc_model model;
96 		unsigned long versions;
97 		unsigned long cpuid;
98 		unsigned long capabilities;
99 		char   sys_model_name[81]; /* PDC-ROM returnes this model name */
100 	} pdc;
101 
102 	const char	*cpu_name;	/* e.g. "PA7300LC (PCX-L2)" */
103 	const char	*family_name;	/* e.g. "1.1e" */
104 };
105 
106 
107 /* Per CPU data structure - ie varies per CPU.  */
108 struct cpuinfo_parisc {
109 	unsigned long it_value;     /* Interval Timer at last timer Intr */
110 	unsigned long it_delta;     /* Interval delta (tic_10ms / HZ * 100) */
111 	unsigned long irq_count;    /* number of IRQ's since boot */
112 	unsigned long irq_max_cr16; /* longest time to handle a single IRQ */
113 	unsigned long cpuid;        /* aka slot_number or set to NO_PROC_ID */
114 	unsigned long hpa;          /* Host Physical address */
115 	unsigned long txn_addr;     /* MMIO addr of EIR or id_eid */
116 #ifdef CONFIG_SMP
117 	unsigned long pending_ipi;  /* bitmap of type ipi_message_type */
118 #endif
119 	unsigned long bh_count;     /* number of times bh was invoked */
120 	unsigned long prof_counter; /* per CPU profiling support */
121 	unsigned long prof_multiplier;	/* per CPU profiling support */
122 	unsigned long fp_rev;
123 	unsigned long fp_model;
124 	unsigned int state;
125 	struct parisc_device *dev;
126 	unsigned long loops_per_jiffy;
127 };
128 
129 extern struct system_cpuinfo_parisc boot_cpu_data;
130 DECLARE_PER_CPU(struct cpuinfo_parisc, cpu_data);
131 
132 #define CPU_HVERSION ((boot_cpu_data.hversion >> 4) & 0x0FFF)
133 
134 typedef struct {
135 	int seg;
136 } mm_segment_t;
137 
138 #define ARCH_MIN_TASKALIGN	8
139 
140 struct thread_struct {
141 	struct pt_regs regs;
142 	unsigned long  task_size;
143 	unsigned long  map_base;
144 	unsigned long  flags;
145 };
146 
147 #define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))
148 
149 /* Thread struct flags. */
150 #define PARISC_UAC_NOPRINT	(1UL << 0)	/* see prctl and unaligned.c */
151 #define PARISC_UAC_SIGBUS	(1UL << 1)
152 #define PARISC_KERNEL_DEATH	(1UL << 31)	/* see die_if_kernel()... */
153 
154 #define PARISC_UAC_SHIFT	0
155 #define PARISC_UAC_MASK		(PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)
156 
157 #define SET_UNALIGN_CTL(task,value)                                       \
158         ({                                                                \
159         (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
160                                 | (((value) << PARISC_UAC_SHIFT) &        \
161                                    PARISC_UAC_MASK));                     \
162         0;                                                                \
163         })
164 
165 #define GET_UNALIGN_CTL(task,addr)                                        \
166         ({                                                                \
167         put_user(((task)->thread.flags & PARISC_UAC_MASK)                 \
168                  >> PARISC_UAC_SHIFT, (int __user *) (addr));             \
169         })
170 
171 #define INIT_THREAD { \
172 	.regs = {	.gr	= { 0, }, \
173 			.fr	= { 0, }, \
174 			.sr	= { 0, }, \
175 			.iasq	= { 0, }, \
176 			.iaoq	= { 0, }, \
177 			.cr27	= 0, \
178 		}, \
179 	.task_size	= DEFAULT_TASK_SIZE, \
180 	.map_base	= DEFAULT_MAP_BASE, \
181 	.flags		= 0 \
182 	}
183 
184 /*
185  * Return saved PC of a blocked thread.  This is used by ps mostly.
186  */
187 
188 struct task_struct;
189 unsigned long thread_saved_pc(struct task_struct *t);
190 void show_trace(struct task_struct *task, unsigned long *stack);
191 
192 /*
193  * Start user thread in another space.
194  *
195  * Note that we set both the iaoq and r31 to the new pc. When
196  * the kernel initially calls execve it will return through an
197  * rfi path that will use the values in the iaoq. The execve
198  * syscall path will return through the gateway page, and
199  * that uses r31 to branch to.
200  *
201  * For ELF we clear r23, because the dynamic linker uses it to pass
202  * the address of the finalizer function.
203  *
204  * We also initialize sr3 to an illegal value (illegal for our
205  * implementation, not for the architecture).
206  */
207 typedef unsigned int elf_caddr_t;
208 
209 #define start_thread_som(regs, new_pc, new_sp) do {	\
210 	unsigned long *sp = (unsigned long *)new_sp;	\
211 	__u32 spaceid = (__u32)current->mm->context;	\
212 	unsigned long pc = (unsigned long)new_pc;	\
213 	/* offset pc for priv. level */			\
214 	pc |= 3;					\
215 							\
216 	regs->iasq[0] = spaceid;			\
217 	regs->iasq[1] = spaceid;			\
218 	regs->iaoq[0] = pc;				\
219 	regs->iaoq[1] = pc + 4;                         \
220 	regs->sr[2] = LINUX_GATEWAY_SPACE;              \
221 	regs->sr[3] = 0xffff;				\
222 	regs->sr[4] = spaceid;				\
223 	regs->sr[5] = spaceid;				\
224 	regs->sr[6] = spaceid;				\
225 	regs->sr[7] = spaceid;				\
226 	regs->gr[ 0] = USER_PSW;                        \
227 	regs->gr[30] = ((new_sp)+63)&~63;		\
228 	regs->gr[31] = pc;				\
229 							\
230 	get_user(regs->gr[26],&sp[0]);			\
231 	get_user(regs->gr[25],&sp[-1]); 		\
232 	get_user(regs->gr[24],&sp[-2]); 		\
233 	get_user(regs->gr[23],&sp[-3]); 		\
234 } while(0)
235 
236 /* The ELF abi wants things done a "wee bit" differently than
237  * som does.  Supporting this behavior here avoids
238  * having our own version of create_elf_tables.
239  *
240  * Oh, and yes, that is not a typo, we are really passing argc in r25
241  * and argv in r24 (rather than r26 and r25).  This is because that's
242  * where __libc_start_main wants them.
243  *
244  * Duplicated from dl-machine.h for the benefit of readers:
245  *
246  *  Our initial stack layout is rather different from everyone else's
247  *  due to the unique PA-RISC ABI.  As far as I know it looks like
248  *  this:
249 
250    -----------------------------------  (user startup code creates this frame)
251    |         32 bytes of magic       |
252    |---------------------------------|
253    | 32 bytes argument/sp save area  |
254    |---------------------------------| (bprm->p)
255    |	    ELF auxiliary info	     |
256    |         (up to 28 words)        |
257    |---------------------------------|
258    |		   NULL		     |
259    |---------------------------------|
260    |	   Environment pointers	     |
261    |---------------------------------|
262    |		   NULL		     |
263    |---------------------------------|
264    |        Argument pointers        |
265    |---------------------------------| <- argv
266    |          argc (1 word)          |
267    |---------------------------------| <- bprm->exec (HACK!)
268    |         N bytes of slack        |
269    |---------------------------------|
270    |	filename passed to execve    |
271    |---------------------------------| (mm->env_end)
272    |           env strings           |
273    |---------------------------------| (mm->env_start, mm->arg_end)
274    |           arg strings           |
275    |---------------------------------|
276    | additional faked arg strings if |
277    | we're invoked via binfmt_script |
278    |---------------------------------| (mm->arg_start)
279    stack base is at TASK_SIZE - rlim_max.
280 
281 on downward growing arches, it looks like this:
282    stack base at TASK_SIZE
283    | filename passed to execve
284    | env strings
285    | arg strings
286    | faked arg strings
287    | slack
288    | ELF
289    | envps
290    | argvs
291    | argc
292 
293  *  The pleasant part of this is that if we need to skip arguments we
294  *  can just decrement argc and move argv, because the stack pointer
295  *  is utterly unrelated to the location of the environment and
296  *  argument vectors.
297  *
298  * Note that the S/390 people took the easy way out and hacked their
299  * GCC to make the stack grow downwards.
300  *
301  * Final Note: For entry from syscall, the W (wide) bit of the PSW
302  * is stuffed into the lowest bit of the user sp (%r30), so we fill
303  * it in here from the current->personality
304  */
305 
306 #ifdef CONFIG_64BIT
307 #define USER_WIDE_MODE	(!test_thread_flag(TIF_32BIT))
308 #else
309 #define USER_WIDE_MODE	0
310 #endif
311 
312 #define start_thread(regs, new_pc, new_sp) do {		\
313 	elf_addr_t *sp = (elf_addr_t *)new_sp;		\
314 	__u32 spaceid = (__u32)current->mm->context;	\
315 	elf_addr_t pc = (elf_addr_t)new_pc | 3;		\
316 	elf_caddr_t *argv = (elf_caddr_t *)bprm->exec + 1;	\
317 							\
318 	regs->iasq[0] = spaceid;			\
319 	regs->iasq[1] = spaceid;			\
320 	regs->iaoq[0] = pc;				\
321 	regs->iaoq[1] = pc + 4;                         \
322 	regs->sr[2] = LINUX_GATEWAY_SPACE;              \
323 	regs->sr[3] = 0xffff;				\
324 	regs->sr[4] = spaceid;				\
325 	regs->sr[5] = spaceid;				\
326 	regs->sr[6] = spaceid;				\
327 	regs->sr[7] = spaceid;				\
328 	regs->gr[ 0] = USER_PSW | (USER_WIDE_MODE ? PSW_W : 0); \
329 	regs->fr[ 0] = 0LL;                            	\
330 	regs->fr[ 1] = 0LL;                            	\
331 	regs->fr[ 2] = 0LL;                            	\
332 	regs->fr[ 3] = 0LL;                            	\
333 	regs->gr[30] = (((unsigned long)sp + 63) &~ 63) | (USER_WIDE_MODE ? 1 : 0); \
334 	regs->gr[31] = pc;				\
335 							\
336 	get_user(regs->gr[25], (argv - 1));		\
337 	regs->gr[24] = (long) argv;			\
338 	regs->gr[23] = 0;				\
339 } while(0)
340 
341 struct task_struct;
342 struct mm_struct;
343 
344 /* Free all resources held by a thread. */
345 extern void release_thread(struct task_struct *);
346 
347 extern void map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm);
348 
349 extern unsigned long get_wchan(struct task_struct *p);
350 
351 #define KSTK_EIP(tsk)	((tsk)->thread.regs.iaoq[0])
352 #define KSTK_ESP(tsk)	((tsk)->thread.regs.gr[30])
353 
354 #define cpu_relax()	barrier()
355 
356 /* Used as a macro to identify the combined VIPT/PIPT cached
357  * CPUs which require a guarantee of coherency (no inequivalent
358  * aliases with different data, whether clean or not) to operate */
359 static inline int parisc_requires_coherency(void)
360 {
361 #ifdef CONFIG_PA8X00
362 	return (boot_cpu_data.cpu_type == mako) ||
363 		(boot_cpu_data.cpu_type == mako2);
364 #else
365 	return 0;
366 #endif
367 }
368 
369 #endif /* __ASSEMBLY__ */
370 
371 #endif /* __ASM_PARISC_PROCESSOR_H */
372