include/asm-powerpc/paca.h

   1 /*
   2  * include/asm-powerpc/paca.h
   3  *
   4  * This control block defines the PACA which defines the processor
   5  * specific data for each logical processor on the system.
   6  * There are some pointers defined that are utilized by PLIC.
   7  *
   8  * C 2001 PPC 64 Team, IBM Corp
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version
  13  * 2 of the License, or (at your option) any later version.
  14  */
  15 #ifndef _ASM_POWERPC_PACA_H
  16 #define _ASM_POWERPC_PACA_H
  17 #ifdef __KERNEL__
  18
  19 #include        <asm/types.h>
  20 #include        <asm/lppaca.h>
  21 #include        <asm/mmu.h>
  22
  23 register struct paca_struct *local_paca asm("r13");
  24
  25 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
  26 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
  27 /*
  28  * Add standard checks that preemption cannot occur when using get_paca():
  29  * otherwise the paca_struct it points to may be the wrong one just after.
  30  */
  31 #define get_paca()      ((void) debug_smp_processor_id(), local_paca)
  32 #else
  33 #define get_paca()      local_paca
  34 #endif
  35
  36 #define get_lppaca()    (get_paca()->lppaca_ptr)
  37 #define get_slb_shadow()        (get_paca()->slb_shadow_ptr)
  38
  39 struct task_struct;
  40
  41 /*
  42  * Defines the layout of the paca.
  43  *
  44  * This structure is not directly accessed by firmware or the service
  45  * processor except for the first two pointers that point to the
  46  * lppaca area and the ItLpRegSave area for this CPU.  The lppaca
  47  * object is currently contained within the PACA but it doesn't need
  48  * to be.
  49  */
  50 struct paca_struct {
  51         /*
  52          * Because hw_cpu_id, unlike other paca fields, is accessed
  53          * routinely from other CPUs (from the IRQ code), we stick to
  54          * read-only (after boot) fields in the first cacheline to
  55          * avoid cacheline bouncing.
  56          */
  57
  58         /*
  59          * MAGIC: These first two pointers can't be moved - they're
  60          * accessed by the firmware
  61          */
  62         struct lppaca *lppaca_ptr;      /* Pointer to LpPaca for PLIC */
  63 #ifdef CONFIG_PPC_ISERIES
  64         void *reg_save_ptr; /* Pointer to LpRegSave for PLIC */
  65 #endif /* CONFIG_PPC_ISERIES */
  66
  67         /*
  68          * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
  69          * load lock_token and paca_index with a single lwz
  70          * instruction.  They must travel together and be properly
  71          * aligned.
  72          */
  73         u16 lock_token;                 /* Constant 0x8000, used in locks */
  74         u16 paca_index;                 /* Logical processor number */
  75
  76         u64 kernel_toc;                 /* Kernel TOC address */
  77         u64 stab_real;                  /* Absolute address of segment table */
  78         u64 stab_addr;                  /* Virtual address of segment table */
  79         void *emergency_sp;             /* pointer to emergency stack */
  80         u64 data_offset;                /* per cpu data offset */
  81         s16 hw_cpu_id;                  /* Physical processor number */
  82         u8 cpu_start;                   /* At startup, processor spins until */
  83                                         /* this becomes non-zero. */
  84         struct slb_shadow *slb_shadow_ptr;
  85
  86         /*
  87          * Now, starting in cacheline 2, the exception save areas
  88          */
  89         /* used for most interrupts/exceptions */
  90         u64 exgen[10] __attribute__((aligned(0x80)));
  91         u64 exmc[10];           /* used for machine checks */
  92         u64 exslb[10];          /* used for SLB/segment table misses
  93                                  * on the linear mapping */
  94
  95         mm_context_t context;
  96         u16 vmalloc_sllp;
  97         u16 slb_cache_ptr;
  98         u16 slb_cache[SLB_CACHE_ENTRIES];
  99
 100         /*
 101          * then miscellaneous read-write fields
 102          */
 103         struct task_struct *__current;  /* Pointer to current */
 104         u64 kstack;                     /* Saved Kernel stack addr */
 105         u64 stab_rr;                    /* stab/slb round-robin counter */
 106         u64 saved_r1;                   /* r1 save for RTAS calls */
 107         u64 saved_msr;                  /* MSR saved here by enter_rtas */
 108         u16 trap_save;                  /* Used when bad stack is encountered */
 109         u8 soft_enabled;                /* irq soft-enable flag */
 110         u8 hard_enabled;                /* set if irqs are enabled in MSR */
 111         u8 io_sync;                     /* writel() needs spin_unlock sync */
 112
 113         /* Stuff for accurate time accounting */
 114         u64 user_time;                  /* accumulated usermode TB ticks */
 115         u64 system_time;                /* accumulated system TB ticks */
 116         u64 startpurr;                  /* PURR/TB value snapshot */
 117         u64 startspurr;                 /* SPURR value snapshot */
 118 };
 119
 120 extern struct paca_struct paca[];
 121
 122 #endif /* __KERNEL__ */
 123 #endif /* _ASM_POWERPC_PACA_H */