arch/parisc/include/asm/processor.h

   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 */