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 typedef struct {
105 	int seg;
106 } mm_segment_t;
107 
108 #define ARCH_MIN_TASKALIGN	8
109 
110 struct thread_struct {
111 	struct pt_regs regs;
112 	unsigned long  task_size;
113 	unsigned long  map_base;
114 	unsigned long  flags;
115 };
116 
117 #define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))
118 
119 /* Thread struct flags. */
120 #define PARISC_UAC_NOPRINT	(1UL << 0)	/* see prctl and unaligned.c */
121 #define PARISC_UAC_SIGBUS	(1UL << 1)
122 #define PARISC_KERNEL_DEATH	(1UL << 31)	/* see die_if_kernel()... */
123 
124 #define PARISC_UAC_SHIFT	0
125 #define PARISC_UAC_MASK		(PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)
126 
127 #define SET_UNALIGN_CTL(task,value)                                       \
128         ({                                                                \
129         (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
130                                 | (((value) << PARISC_UAC_SHIFT) &        \
131                                    PARISC_UAC_MASK));                     \
132         0;                                                                \
133         })
134 
135 #define GET_UNALIGN_CTL(task,addr)                                        \
136         ({                                                                \
137         put_user(((task)->thread.flags & PARISC_UAC_MASK)                 \
138                  >> PARISC_UAC_SHIFT, (int __user *) (addr));             \
139         })
140 
141 #define INIT_THREAD { \
142 	.regs = {	.gr	= { 0, }, \
143 			.fr	= { 0, }, \
144 			.sr	= { 0, }, \
145 			.iasq	= { 0, }, \
146 			.iaoq	= { 0, }, \
147 			.cr27	= 0, \
148 		}, \
149 	.task_size	= DEFAULT_TASK_SIZE, \
150 	.map_base	= DEFAULT_MAP_BASE, \
151 	.flags		= 0 \
152 	}
153 
154 struct task_struct;
155 void show_trace(struct task_struct *task, unsigned long *stack);
156 
157 /*
158  * Start user thread in another space.
159  *
160  * Note that we set both the iaoq and r31 to the new pc. When
161  * the kernel initially calls execve it will return through an
162  * rfi path that will use the values in the iaoq. The execve
163  * syscall path will return through the gateway page, and
164  * that uses r31 to branch to.
165  *
166  * For ELF we clear r23, because the dynamic linker uses it to pass
167  * the address of the finalizer function.
168  *
169  * We also initialize sr3 to an illegal value (illegal for our
170  * implementation, not for the architecture).
171  */
172 typedef unsigned int elf_caddr_t;
173 
174 /* The ELF abi wants things done a "wee bit" differently than
175  * som does.  Supporting this behavior here avoids
176  * having our own version of create_elf_tables.
177  *
178  * Oh, and yes, that is not a typo, we are really passing argc in r25
179  * and argv in r24 (rather than r26 and r25).  This is because that's
180  * where __libc_start_main wants them.
181  *
182  * Duplicated from dl-machine.h for the benefit of readers:
183  *
184  *  Our initial stack layout is rather different from everyone else's
185  *  due to the unique PA-RISC ABI.  As far as I know it looks like
186  *  this:
187 
188    -----------------------------------  (user startup code creates this frame)
189    |         32 bytes of magic       |
190    |---------------------------------|
191    | 32 bytes argument/sp save area  |
192    |---------------------------------| (bprm->p)
193    |	    ELF auxiliary info	     |
194    |         (up to 28 words)        |
195    |---------------------------------|
196    |		   NULL		     |
197    |---------------------------------|
198    |	   Environment pointers	     |
199    |---------------------------------|
200    |		   NULL		     |
201    |---------------------------------|
202    |        Argument pointers        |
203    |---------------------------------| <- argv
204    |          argc (1 word)          |
205    |---------------------------------| <- bprm->exec (HACK!)
206    |         N bytes of slack        |
207    |---------------------------------|
208    |	filename passed to execve    |
209    |---------------------------------| (mm->env_end)
210    |           env strings           |
211    |---------------------------------| (mm->env_start, mm->arg_end)
212    |           arg strings           |
213    |---------------------------------|
214    | additional faked arg strings if |
215    | we're invoked via binfmt_script |
216    |---------------------------------| (mm->arg_start)
217    stack base is at TASK_SIZE - rlim_max.
218 
219 on downward growing arches, it looks like this:
220    stack base at TASK_SIZE
221    | filename passed to execve
222    | env strings
223    | arg strings
224    | faked arg strings
225    | slack
226    | ELF
227    | envps
228    | argvs
229    | argc
230 
231  *  The pleasant part of this is that if we need to skip arguments we
232  *  can just decrement argc and move argv, because the stack pointer
233  *  is utterly unrelated to the location of the environment and
234  *  argument vectors.
235  *
236  * Note that the S/390 people took the easy way out and hacked their
237  * GCC to make the stack grow downwards.
238  *
239  * Final Note: For entry from syscall, the W (wide) bit of the PSW
240  * is stuffed into the lowest bit of the user sp (%r30), so we fill
241  * it in here from the current->personality
242  */
243 
244 #define USER_WIDE_MODE	(!is_32bit_task())
245 
246 #define start_thread(regs, new_pc, new_sp) do {		\
247 	elf_addr_t *sp = (elf_addr_t *)new_sp;		\
248 	__u32 spaceid = (__u32)current->mm->context;	\
249 	elf_addr_t pc = (elf_addr_t)new_pc | 3;		\
250 	elf_caddr_t *argv = (elf_caddr_t *)bprm->exec + 1;	\
251 							\
252 	regs->iasq[0] = spaceid;			\
253 	regs->iasq[1] = spaceid;			\
254 	regs->iaoq[0] = pc;				\
255 	regs->iaoq[1] = pc + 4;                         \
256 	regs->sr[2] = LINUX_GATEWAY_SPACE;              \
257 	regs->sr[3] = 0xffff;				\
258 	regs->sr[4] = spaceid;				\
259 	regs->sr[5] = spaceid;				\
260 	regs->sr[6] = spaceid;				\
261 	regs->sr[7] = spaceid;				\
262 	regs->gr[ 0] = USER_PSW | (USER_WIDE_MODE ? PSW_W : 0); \
263 	regs->fr[ 0] = 0LL;                            	\
264 	regs->fr[ 1] = 0LL;                            	\
265 	regs->fr[ 2] = 0LL;                            	\
266 	regs->fr[ 3] = 0LL;                            	\
267 	regs->gr[30] = (((unsigned long)sp + 63) &~ 63) | (USER_WIDE_MODE ? 1 : 0); \
268 	regs->gr[31] = pc;				\
269 							\
270 	get_user(regs->gr[25], (argv - 1));		\
271 	regs->gr[24] = (long) argv;			\
272 	regs->gr[23] = 0;				\
273 } while(0)
274 
275 struct mm_struct;
276 
277 /* Free all resources held by a thread. */
278 extern void release_thread(struct task_struct *);
279 
280 extern unsigned long get_wchan(struct task_struct *p);
281 
282 #define KSTK_EIP(tsk)	((tsk)->thread.regs.iaoq[0])
283 #define KSTK_ESP(tsk)	((tsk)->thread.regs.gr[30])
284 
285 #define cpu_relax()	barrier()
286 
287 /*
288  * parisc_requires_coherency() is used to identify the combined VIPT/PIPT
289  * cached CPUs which require a guarantee of coherency (no inequivalent aliases
290  * with different data, whether clean or not) to operate
291  */
292 #ifdef CONFIG_PA8X00
293 extern int _parisc_requires_coherency;
294 #define parisc_requires_coherency()	_parisc_requires_coherency
295 #else
296 #define parisc_requires_coherency()	(0)
297 #endif
298 
299 extern int running_on_qemu;
300 
301 #endif /* __ASSEMBLY__ */
302 
303 #endif /* __ASM_PARISC_PROCESSOR_H */
304