1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * include/asm-parisc/processor.h
4  *
5  * Copyright (C) 1994 Linus Torvalds
6  * Copyright (C) 2001 Grant Grundler
7  */
8 
9 #ifndef __ASM_PARISC_PROCESSOR_H
10 #define __ASM_PARISC_PROCESSOR_H
11 
12 #ifndef __ASSEMBLY__
13 #include <linux/threads.h>
14 
15 #include <asm/prefetch.h>
16 #include <asm/hardware.h>
17 #include <asm/pdc.h>
18 #include <asm/ptrace.h>
19 #include <asm/types.h>
20 #include <asm/percpu.h>
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 HAVE_ARCH_PICK_MMAP_LAYOUT
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 /* Allow bigger stacks for 64-bit processes */
60 #define STACK_SIZE_MAX	(USER_WIDE_MODE					\
61 			 ? (1 << 30)	/* 1 GB */			\
62 			 : (CONFIG_MAX_STACK_SIZE_MB*1024*1024))
63 
64 #endif
65 
66 #ifndef __ASSEMBLY__
67 
68 /*
69  * Data detected about CPUs at boot time which is the same for all CPU's.
70  * HP boxes are SMP - ie identical processors.
71  *
72  * FIXME: some CPU rev info may be processor specific...
73  */
74 struct system_cpuinfo_parisc {
75 	unsigned int	cpu_count;
76 	unsigned int	cpu_hz;
77 	unsigned int	hversion;
78 	unsigned int	sversion;
79 	enum cpu_type	cpu_type;
80 
81 	struct {
82 		struct pdc_model model;
83 		unsigned long versions;
84 		unsigned long cpuid;
85 		unsigned long capabilities;
86 		char   sys_model_name[81]; /* PDC-ROM returnes this model name */
87 	} pdc;
88 
89 	const char	*cpu_name;	/* e.g. "PA7300LC (PCX-L2)" */
90 	const char	*family_name;	/* e.g. "1.1e" */
91 };
92 
93 
94 /* Per CPU data structure - ie varies per CPU.  */
95 struct cpuinfo_parisc {
96 	unsigned long it_value;     /* Interval Timer at last timer Intr */
97 	unsigned long irq_count;    /* number of IRQ's since boot */
98 	unsigned long cpuid;        /* aka slot_number or set to NO_PROC_ID */
99 	unsigned long hpa;          /* Host Physical address */
100 	unsigned long txn_addr;     /* MMIO addr of EIR or id_eid */
101 #ifdef CONFIG_SMP
102 	unsigned long pending_ipi;  /* bitmap of type ipi_message_type */
103 #endif
104 	unsigned long bh_count;     /* number of times bh was invoked */
105 	unsigned long fp_rev;
106 	unsigned long fp_model;
107 	unsigned long cpu_num;      /* CPU number from PAT firmware */
108 	unsigned long cpu_loc;      /* CPU location from PAT firmware */
109 	unsigned int state;
110 	struct parisc_device *dev;
111 	unsigned long loops_per_jiffy;
112 };
113 
114 extern struct system_cpuinfo_parisc boot_cpu_data;
115 DECLARE_PER_CPU(struct cpuinfo_parisc, cpu_data);
116 
117 #define CPU_HVERSION ((boot_cpu_data.hversion >> 4) & 0x0FFF)
118 
119 typedef struct {
120 	int seg;
121 } mm_segment_t;
122 
123 #define ARCH_MIN_TASKALIGN	8
124 
125 struct thread_struct {
126 	struct pt_regs regs;
127 	unsigned long  task_size;
128 	unsigned long  map_base;
129 	unsigned long  flags;
130 };
131 
132 #define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))
133 
134 /* Thread struct flags. */
135 #define PARISC_UAC_NOPRINT	(1UL << 0)	/* see prctl and unaligned.c */
136 #define PARISC_UAC_SIGBUS	(1UL << 1)
137 #define PARISC_KERNEL_DEATH	(1UL << 31)	/* see die_if_kernel()... */
138 
139 #define PARISC_UAC_SHIFT	0
140 #define PARISC_UAC_MASK		(PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)
141 
142 #define SET_UNALIGN_CTL(task,value)                                       \
143         ({                                                                \
144         (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
145                                 | (((value) << PARISC_UAC_SHIFT) &        \
146                                    PARISC_UAC_MASK));                     \
147         0;                                                                \
148         })
149 
150 #define GET_UNALIGN_CTL(task,addr)                                        \
151         ({                                                                \
152         put_user(((task)->thread.flags & PARISC_UAC_MASK)                 \
153                  >> PARISC_UAC_SHIFT, (int __user *) (addr));             \
154         })
155 
156 #define INIT_THREAD { \
157 	.regs = {	.gr	= { 0, }, \
158 			.fr	= { 0, }, \
159 			.sr	= { 0, }, \
160 			.iasq	= { 0, }, \
161 			.iaoq	= { 0, }, \
162 			.cr27	= 0, \
163 		}, \
164 	.task_size	= DEFAULT_TASK_SIZE, \
165 	.map_base	= DEFAULT_MAP_BASE, \
166 	.flags		= 0 \
167 	}
168 
169 struct task_struct;
170 void show_trace(struct task_struct *task, unsigned long *stack);
171 
172 /*
173  * Start user thread in another space.
174  *
175  * Note that we set both the iaoq and r31 to the new pc. When
176  * the kernel initially calls execve it will return through an
177  * rfi path that will use the values in the iaoq. The execve
178  * syscall path will return through the gateway page, and
179  * that uses r31 to branch to.
180  *
181  * For ELF we clear r23, because the dynamic linker uses it to pass
182  * the address of the finalizer function.
183  *
184  * We also initialize sr3 to an illegal value (illegal for our
185  * implementation, not for the architecture).
186  */
187 typedef unsigned int elf_caddr_t;
188 
189 /* The ELF abi wants things done a "wee bit" differently than
190  * som does.  Supporting this behavior here avoids
191  * having our own version of create_elf_tables.
192  *
193  * Oh, and yes, that is not a typo, we are really passing argc in r25
194  * and argv in r24 (rather than r26 and r25).  This is because that's
195  * where __libc_start_main wants them.
196  *
197  * Duplicated from dl-machine.h for the benefit of readers:
198  *
199  *  Our initial stack layout is rather different from everyone else's
200  *  due to the unique PA-RISC ABI.  As far as I know it looks like
201  *  this:
202 
203    -----------------------------------  (user startup code creates this frame)
204    |         32 bytes of magic       |
205    |---------------------------------|
206    | 32 bytes argument/sp save area  |
207    |---------------------------------| (bprm->p)
208    |	    ELF auxiliary info	     |
209    |         (up to 28 words)        |
210    |---------------------------------|
211    |		   NULL		     |
212    |---------------------------------|
213    |	   Environment pointers	     |
214    |---------------------------------|
215    |		   NULL		     |
216    |---------------------------------|
217    |        Argument pointers        |
218    |---------------------------------| <- argv
219    |          argc (1 word)          |
220    |---------------------------------| <- bprm->exec (HACK!)
221    |         N bytes of slack        |
222    |---------------------------------|
223    |	filename passed to execve    |
224    |---------------------------------| (mm->env_end)
225    |           env strings           |
226    |---------------------------------| (mm->env_start, mm->arg_end)
227    |           arg strings           |
228    |---------------------------------|
229    | additional faked arg strings if |
230    | we're invoked via binfmt_script |
231    |---------------------------------| (mm->arg_start)
232    stack base is at TASK_SIZE - rlim_max.
233 
234 on downward growing arches, it looks like this:
235    stack base at TASK_SIZE
236    | filename passed to execve
237    | env strings
238    | arg strings
239    | faked arg strings
240    | slack
241    | ELF
242    | envps
243    | argvs
244    | argc
245 
246  *  The pleasant part of this is that if we need to skip arguments we
247  *  can just decrement argc and move argv, because the stack pointer
248  *  is utterly unrelated to the location of the environment and
249  *  argument vectors.
250  *
251  * Note that the S/390 people took the easy way out and hacked their
252  * GCC to make the stack grow downwards.
253  *
254  * Final Note: For entry from syscall, the W (wide) bit of the PSW
255  * is stuffed into the lowest bit of the user sp (%r30), so we fill
256  * it in here from the current->personality
257  */
258 
259 #ifdef CONFIG_64BIT
260 #define USER_WIDE_MODE	(!test_thread_flag(TIF_32BIT))
261 #else
262 #define USER_WIDE_MODE	0
263 #endif
264 
265 #define start_thread(regs, new_pc, new_sp) do {		\
266 	elf_addr_t *sp = (elf_addr_t *)new_sp;		\
267 	__u32 spaceid = (__u32)current->mm->context;	\
268 	elf_addr_t pc = (elf_addr_t)new_pc | 3;		\
269 	elf_caddr_t *argv = (elf_caddr_t *)bprm->exec + 1;	\
270 							\
271 	regs->iasq[0] = spaceid;			\
272 	regs->iasq[1] = spaceid;			\
273 	regs->iaoq[0] = pc;				\
274 	regs->iaoq[1] = pc + 4;                         \
275 	regs->sr[2] = LINUX_GATEWAY_SPACE;              \
276 	regs->sr[3] = 0xffff;				\
277 	regs->sr[4] = spaceid;				\
278 	regs->sr[5] = spaceid;				\
279 	regs->sr[6] = spaceid;				\
280 	regs->sr[7] = spaceid;				\
281 	regs->gr[ 0] = USER_PSW | (USER_WIDE_MODE ? PSW_W : 0); \
282 	regs->fr[ 0] = 0LL;                            	\
283 	regs->fr[ 1] = 0LL;                            	\
284 	regs->fr[ 2] = 0LL;                            	\
285 	regs->fr[ 3] = 0LL;                            	\
286 	regs->gr[30] = (((unsigned long)sp + 63) &~ 63) | (USER_WIDE_MODE ? 1 : 0); \
287 	regs->gr[31] = pc;				\
288 							\
289 	get_user(regs->gr[25], (argv - 1));		\
290 	regs->gr[24] = (long) argv;			\
291 	regs->gr[23] = 0;				\
292 } while(0)
293 
294 struct task_struct;
295 struct mm_struct;
296 
297 /* Free all resources held by a thread. */
298 extern void release_thread(struct task_struct *);
299 
300 extern unsigned long get_wchan(struct task_struct *p);
301 
302 #define KSTK_EIP(tsk)	((tsk)->thread.regs.iaoq[0])
303 #define KSTK_ESP(tsk)	((tsk)->thread.regs.gr[30])
304 
305 #define cpu_relax()	barrier()
306 
307 /*
308  * parisc_requires_coherency() is used to identify the combined VIPT/PIPT
309  * cached CPUs which require a guarantee of coherency (no inequivalent aliases
310  * with different data, whether clean or not) to operate
311  */
312 #ifdef CONFIG_PA8X00
313 extern int _parisc_requires_coherency;
314 #define parisc_requires_coherency()	_parisc_requires_coherency
315 #else
316 #define parisc_requires_coherency()	(0)
317 #endif
318 
319 extern int running_on_qemu;
320 
321 #endif /* __ASSEMBLY__ */
322 
323 #endif /* __ASM_PARISC_PROCESSOR_H */
324