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