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