arch/powerpc/include/asm/paca.h

   1 /*
   2  * This control block defines the PACA which defines the processor
   3  * specific data for each logical processor on the system.
   4  * There are some pointers defined that are utilized by PLIC.
   5  *
   6  * C 2001 PPC 64 Team, IBM Corp
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version
  11  * 2 of the License, or (at your option) any later version.
  12  */
  13 #ifndef _ASM_POWERPC_PACA_H
  14 #define _ASM_POWERPC_PACA_H
  15 #ifdef __KERNEL__
  16
  17 #include        <asm/types.h>
  18 #include        <asm/lppaca.h>
  19 #include        <asm/mmu.h>
  20
  21 register struct paca_struct *local_paca asm("r13");
  22
  23 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
  24 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
  25 /*
  26  * Add standard checks that preemption cannot occur when using get_paca():
  27  * otherwise the paca_struct it points to may be the wrong one just after.
  28  */
  29 #define get_paca()      ((void) debug_smp_processor_id(), local_paca)
  30 #else
  31 #define get_paca()      local_paca
  32 #endif
  33
  34 #define get_lppaca()    (get_paca()->lppaca_ptr)
  35 #define get_slb_shadow()        (get_paca()->slb_shadow_ptr)
  36
  37 struct task_struct;
  38
  39 /*
  40  * Defines the layout of the paca.
  41  *
  42  * This structure is not directly accessed by firmware or the service
  43  * processor.
  44  */
  45 struct paca_struct {
  46         /*
  47          * Because hw_cpu_id, unlike other paca fields, is accessed
  48          * routinely from other CPUs (from the IRQ code), we stick to
  49          * read-only (after boot) fields in the first cacheline to
  50          * avoid cacheline bouncing.
  51          */
  52
  53         struct lppaca *lppaca_ptr;      /* Pointer to LpPaca for PLIC */
  54
  55         /*
  56          * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
  57          * load lock_token and paca_index with a single lwz
  58          * instruction.  They must travel together and be properly
  59          * aligned.
  60          */
  61         u16 lock_token;                 /* Constant 0x8000, used in locks */
  62         u16 paca_index;                 /* Logical processor number */
  63
  64         u64 kernel_toc;                 /* Kernel TOC address */
  65         u64 stab_real;                  /* Absolute address of segment table */
  66         u64 stab_addr;                  /* Virtual address of segment table */
  67         void *emergency_sp;             /* pointer to emergency stack */
  68         u64 data_offset;                /* per cpu data offset */
  69         s16 hw_cpu_id;                  /* Physical processor number */
  70         u8 cpu_start;                   /* At startup, processor spins until */
  71                                         /* this becomes non-zero. */
  72         struct slb_shadow *slb_shadow_ptr;
  73
  74         /*
  75          * Now, starting in cacheline 2, the exception save areas
  76          */
  77         /* used for most interrupts/exceptions */
  78         u64 exgen[10] __attribute__((aligned(0x80)));
  79         u64 exmc[10];           /* used for machine checks */
  80         u64 exslb[10];          /* used for SLB/segment table misses
  81                                  * on the linear mapping */
  82
  83         mm_context_t context;
  84         u16 vmalloc_sllp;
  85         u16 slb_cache_ptr;
  86         u16 slb_cache[SLB_CACHE_ENTRIES];
  87
  88         /*
  89          * then miscellaneous read-write fields
  90          */
  91         struct task_struct *__current;  /* Pointer to current */
  92         u64 kstack;                     /* Saved Kernel stack addr */
  93         u64 stab_rr;                    /* stab/slb round-robin counter */
  94         u64 saved_r1;                   /* r1 save for RTAS calls */
  95         u64 saved_msr;                  /* MSR saved here by enter_rtas */
  96         u16 trap_save;                  /* Used when bad stack is encountered */
  97         u8 soft_enabled;                /* irq soft-enable flag */
  98         u8 hard_enabled;                /* set if irqs are enabled in MSR */
  99         u8 io_sync;                     /* writel() needs spin_unlock sync */
 100
 101         /* Stuff for accurate time accounting */
 102         u64 user_time;                  /* accumulated usermode TB ticks */
 103         u64 system_time;                /* accumulated system TB ticks */
 104         u64 startpurr;                  /* PURR/TB value snapshot */
 105         u64 startspurr;                 /* SPURR value snapshot */
 106 };
 107
 108 extern struct paca_struct paca[];
 109 extern void initialise_pacas(void);
 110
 111 #endif /* __KERNEL__ */
 112 #endif /* _ASM_POWERPC_PACA_H */