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 #define HAVE_ARCH_PICK_MMAP_LAYOUT
24 
25 #define TASK_SIZE_OF(tsk)       ((tsk)->thread.task_size)
26 #define TASK_SIZE	        TASK_SIZE_OF(current)
27 #define TASK_UNMAPPED_BASE      (current->thread.map_base)
28 
29 #define DEFAULT_TASK_SIZE32	(0xFFF00000UL)
30 #define DEFAULT_MAP_BASE32	(0x40000000UL)
31 
32 #ifdef CONFIG_64BIT
33 #define DEFAULT_TASK_SIZE       (MAX_ADDRESS-0xf000000)
34 #define DEFAULT_MAP_BASE        (0x200000000UL)
35 #else
36 #define DEFAULT_TASK_SIZE	DEFAULT_TASK_SIZE32
37 #define DEFAULT_MAP_BASE	DEFAULT_MAP_BASE32
38 #endif
39 
40 #ifdef __KERNEL__
41 
42 /* XXX: STACK_TOP actually should be STACK_BOTTOM for parisc.
43  * prumpf */
44 
45 #define STACK_TOP	TASK_SIZE
46 #define STACK_TOP_MAX	DEFAULT_TASK_SIZE
47 
48 #endif
49 
50 #ifndef __ASSEMBLY__
51 
52 unsigned long calc_max_stack_size(unsigned long stack_max);
53 
54 /*
55  * Data detected about CPUs at boot time which is the same for all CPU's.
56  * HP boxes are SMP - ie identical processors.
57  *
58  * FIXME: some CPU rev info may be processor specific...
59  */
60 struct system_cpuinfo_parisc {
61 	unsigned int	cpu_count;
62 	unsigned int	cpu_hz;
63 	unsigned int	hversion;
64 	unsigned int	sversion;
65 	enum cpu_type	cpu_type;
66 
67 	struct {
68 		struct pdc_model model;
69 		unsigned long versions;
70 		unsigned long cpuid;
71 		unsigned long capabilities;
72 		char   sys_model_name[81]; /* PDC-ROM returnes this model name */
73 	} pdc;
74 
75 	const char	*cpu_name;	/* e.g. "PA7300LC (PCX-L2)" */
76 	const char	*family_name;	/* e.g. "1.1e" */
77 };
78 
79 
80 /* Per CPU data structure - ie varies per CPU.  */
81 struct cpuinfo_parisc {
82 	unsigned long it_value;     /* Interval Timer at last timer Intr */
83 	unsigned long irq_count;    /* number of IRQ's since boot */
84 	unsigned long cpuid;        /* aka slot_number or set to NO_PROC_ID */
85 	unsigned long hpa;          /* Host Physical address */
86 	unsigned long txn_addr;     /* MMIO addr of EIR or id_eid */
87 #ifdef CONFIG_SMP
88 	unsigned long pending_ipi;  /* bitmap of type ipi_message_type */
89 #endif
90 	unsigned long bh_count;     /* number of times bh was invoked */
91 	unsigned long fp_rev;
92 	unsigned long fp_model;
93 	unsigned long cpu_num;      /* CPU number from PAT firmware */
94 	unsigned long cpu_loc;      /* CPU location from PAT firmware */
95 	unsigned int state;
96 	struct parisc_device *dev;
97 };
98 
99 extern struct system_cpuinfo_parisc boot_cpu_data;
100 DECLARE_PER_CPU(struct cpuinfo_parisc, cpu_data);
101 
102 #define CPU_HVERSION ((boot_cpu_data.hversion >> 4) & 0x0FFF)
103 
104 #define ARCH_MIN_TASKALIGN	8
105 
106 struct thread_struct {
107 	struct pt_regs regs;
108 	unsigned long  task_size;
109 	unsigned long  map_base;
110 	unsigned long  flags;
111 };
112 
113 #define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))
114 
115 /* Thread struct flags. */
116 #define PARISC_UAC_NOPRINT	(1UL << 0)	/* see prctl and unaligned.c */
117 #define PARISC_UAC_SIGBUS	(1UL << 1)
118 #define PARISC_KERNEL_DEATH	(1UL << 31)	/* see die_if_kernel()... */
119 
120 #define PARISC_UAC_SHIFT	0
121 #define PARISC_UAC_MASK		(PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)
122 
123 #define SET_UNALIGN_CTL(task,value)                                       \
124         ({                                                                \
125         (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
126                                 | (((value) << PARISC_UAC_SHIFT) &        \
127                                    PARISC_UAC_MASK));                     \
128         0;                                                                \
129         })
130 
131 #define GET_UNALIGN_CTL(task,addr)                                        \
132         ({                                                                \
133         put_user(((task)->thread.flags & PARISC_UAC_MASK)                 \
134                  >> PARISC_UAC_SHIFT, (int __user *) (addr));             \
135         })
136 
137 #define INIT_THREAD { \
138 	.regs = {	.gr	= { 0, }, \
139 			.fr	= { 0, }, \
140 			.sr	= { 0, }, \
141 			.iasq	= { 0, }, \
142 			.iaoq	= { 0, }, \
143 			.cr27	= 0, \
144 		}, \
145 	.task_size	= DEFAULT_TASK_SIZE, \
146 	.map_base	= DEFAULT_MAP_BASE, \
147 	.flags		= 0 \
148 	}
149 
150 struct task_struct;
151 void show_trace(struct task_struct *task, unsigned long *stack);
152 
153 /*
154  * Start user thread in another space.
155  *
156  * Note that we set both the iaoq and r31 to the new pc. When
157  * the kernel initially calls execve it will return through an
158  * rfi path that will use the values in the iaoq. The execve
159  * syscall path will return through the gateway page, and
160  * that uses r31 to branch to.
161  *
162  * For ELF we clear r23, because the dynamic linker uses it to pass
163  * the address of the finalizer function.
164  *
165  * We also initialize sr3 to an illegal value (illegal for our
166  * implementation, not for the architecture).
167  */
168 typedef unsigned int elf_caddr_t;
169 
170 /* The ELF abi wants things done a "wee bit" differently than
171  * som does.  Supporting this behavior here avoids
172  * having our own version of create_elf_tables.
173  *
174  * Oh, and yes, that is not a typo, we are really passing argc in r25
175  * and argv in r24 (rather than r26 and r25).  This is because that's
176  * where __libc_start_main wants them.
177  *
178  * Duplicated from dl-machine.h for the benefit of readers:
179  *
180  *  Our initial stack layout is rather different from everyone else's
181  *  due to the unique PA-RISC ABI.  As far as I know it looks like
182  *  this:
183 
184    -----------------------------------  (user startup code creates this frame)
185    |         32 bytes of magic       |
186    |---------------------------------|
187    | 32 bytes argument/sp save area  |
188    |---------------------------------| (bprm->p)
189    |	    ELF auxiliary info	     |
190    |         (up to 28 words)        |
191    |---------------------------------|
192    |		   NULL		     |
193    |---------------------------------|
194    |	   Environment pointers	     |
195    |---------------------------------|
196    |		   NULL		     |
197    |---------------------------------|
198    |        Argument pointers        |
199    |---------------------------------| <- argv
200    |          argc (1 word)          |
201    |---------------------------------| <- bprm->exec (HACK!)
202    |         N bytes of slack        |
203    |---------------------------------|
204    |	filename passed to execve    |
205    |---------------------------------| (mm->env_end)
206    |           env strings           |
207    |---------------------------------| (mm->env_start, mm->arg_end)
208    |           arg strings           |
209    |---------------------------------|
210    | additional faked arg strings if |
211    | we're invoked via binfmt_script |
212    |---------------------------------| (mm->arg_start)
213    stack base is at TASK_SIZE - rlim_max.
214 
215 on downward growing arches, it looks like this:
216    stack base at TASK_SIZE
217    | filename passed to execve
218    | env strings
219    | arg strings
220    | faked arg strings
221    | slack
222    | ELF
223    | envps
224    | argvs
225    | argc
226 
227  *  The pleasant part of this is that if we need to skip arguments we
228  *  can just decrement argc and move argv, because the stack pointer
229  *  is utterly unrelated to the location of the environment and
230  *  argument vectors.
231  *
232  * Note that the S/390 people took the easy way out and hacked their
233  * GCC to make the stack grow downwards.
234  *
235  * Final Note: For entry from syscall, the W (wide) bit of the PSW
236  * is stuffed into the lowest bit of the user sp (%r30), so we fill
237  * it in here from the current->personality
238  */
239 
240 #define USER_WIDE_MODE	(!is_32bit_task())
241 
242 #define start_thread(regs, new_pc, new_sp) do {		\
243 	elf_addr_t *sp = (elf_addr_t *)new_sp;		\
244 	__u32 spaceid = (__u32)current->mm->context;	\
245 	elf_addr_t pc = (elf_addr_t)new_pc | 3;		\
246 	elf_caddr_t *argv = (elf_caddr_t *)bprm->exec + 1;	\
247 							\
248 	regs->iasq[0] = spaceid;			\
249 	regs->iasq[1] = spaceid;			\
250 	regs->iaoq[0] = pc;				\
251 	regs->iaoq[1] = pc + 4;                         \
252 	regs->sr[2] = LINUX_GATEWAY_SPACE;              \
253 	regs->sr[3] = 0xffff;				\
254 	regs->sr[4] = spaceid;				\
255 	regs->sr[5] = spaceid;				\
256 	regs->sr[6] = spaceid;				\
257 	regs->sr[7] = spaceid;				\
258 	regs->gr[ 0] = USER_PSW | (USER_WIDE_MODE ? PSW_W : 0); \
259 	regs->fr[ 0] = 0LL;                            	\
260 	regs->fr[ 1] = 0LL;                            	\
261 	regs->fr[ 2] = 0LL;                            	\
262 	regs->fr[ 3] = 0LL;                            	\
263 	regs->gr[30] = (((unsigned long)sp + 63) &~ 63) | (USER_WIDE_MODE ? 1 : 0); \
264 	regs->gr[31] = pc;				\
265 							\
266 	get_user(regs->gr[25], (argv - 1));		\
267 	regs->gr[24] = (long) argv;			\
268 	regs->gr[23] = 0;				\
269 } while(0)
270 
271 struct mm_struct;
272 
273 /* Free all resources held by a thread. */
274 extern void release_thread(struct task_struct *);
275 
276 extern unsigned long get_wchan(struct task_struct *p);
277 
278 #define KSTK_EIP(tsk)	((tsk)->thread.regs.iaoq[0])
279 #define KSTK_ESP(tsk)	((tsk)->thread.regs.gr[30])
280 
281 #define cpu_relax()	barrier()
282 
283 /*
284  * parisc_requires_coherency() is used to identify the combined VIPT/PIPT
285  * cached CPUs which require a guarantee of coherency (no inequivalent aliases
286  * with different data, whether clean or not) to operate
287  */
288 #ifdef CONFIG_PA8X00
289 extern int _parisc_requires_coherency;
290 #define parisc_requires_coherency()	_parisc_requires_coherency
291 #else
292 #define parisc_requires_coherency()	(0)
293 #endif
294 
295 extern int running_on_qemu;
296 
297 #endif /* __ASSEMBLY__ */
298 
299 #endif /* __ASM_PARISC_PROCESSOR_H */
300