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