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