paca.h

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/*
 * This control block defines the PACA which defines the processor
 * specific data for each logical processor on the system.
 * There are some pointers defined that are utilized by PLIC.
 *
 * C 2001 PPC 64 Team, IBM Corp
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */
#ifndef _ASM_POWERPC_PACA_H
#define _ASM_POWERPC_PACA_H
#ifdef __KERNEL__

#ifdef CONFIG_PPC64

#include <linux/init.h>
#include <asm/types.h>
#include <asm/lppaca.h>
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/exception-64e.h>
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
#include <asm/kvm_book3s_asm.h>
#endif

register struct paca_struct *local_paca asm("r13");

#if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
/*
 * Add standard checks that preemption cannot occur when using get_paca():
 * otherwise the paca_struct it points to may be the wrong one just after.
 */
#define get_paca()  ((void) debug_smp_processor_id(), local_paca)
#else
#define get_paca()  local_paca
#endif

#define get_lppaca()    (get_paca()->lppaca_ptr)
#define get_slb_shadow()    (get_paca()->slb_shadow_ptr)

struct task_struct;
struct opal_machine_check_event;

/*
 * Defines the layout of the paca.
 *
 * This structure is not directly accessed by firmware or the service
 * processor.
 */
struct paca_struct {
#ifdef CONFIG_PPC_BOOK3S
    /*
     * Because hw_cpu_id, unlike other paca fields, is accessed
     * routinely from other CPUs (from the IRQ code), we stick to
     * read-only (after boot) fields in the first cacheline to
     * avoid cacheline bouncing.
     */

    struct lppaca *lppaca_ptr;  /* Pointer to LpPaca for PLIC */
#endif /* CONFIG_PPC_BOOK3S */
    /*
     * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c 
     * load lock_token and paca_index with a single lwz
     * instruction.  They must travel together and be properly
     * aligned.
     */
    u16 lock_token;         /* Constant 0x8000, used in locks */
    u16 paca_index;         /* Logical processor number */

    u64 kernel_toc;         /* Kernel TOC address */
    u64 kernelbase;         /* Base address of kernel */
    u64 kernel_msr;         /* MSR while running in kernel */
#ifdef CONFIG_PPC_STD_MMU_64
    u64 stab_real;          /* Absolute address of segment table */
    u64 stab_addr;          /* Virtual address of segment table */
#endif /* CONFIG_PPC_STD_MMU_64 */
    void *emergency_sp;     /* pointer to emergency stack */
    u64 data_offset;        /* per cpu data offset */
    s16 hw_cpu_id;          /* Physical processor number */
    u8 cpu_start;           /* At startup, processor spins until */
                    /* this becomes non-zero. */
    u8 kexec_state;     /* set when kexec down has irqs off */
#ifdef CONFIG_PPC_STD_MMU_64
    struct slb_shadow *slb_shadow_ptr;
    struct dtl_entry *dispatch_log;
    struct dtl_entry *dispatch_log_end;

    /*
     * Now, starting in cacheline 2, the exception save areas
     */
    /* used for most interrupts/exceptions */
    u64 exgen[11] __attribute__((aligned(0x80)));
    u64 exmc[11];       /* used for machine checks */
    u64 exslb[11];      /* used for SLB/segment table misses
                 * on the linear mapping */
    /* SLB related definitions */
    u16 vmalloc_sllp;
    u16 slb_cache_ptr;
    u32 slb_cache[SLB_CACHE_ENTRIES];
#endif /* CONFIG_PPC_STD_MMU_64 */

#ifdef CONFIG_PPC_BOOK3E
    u64 exgen[8] __attribute__((aligned(0x80)));
    /* Keep pgd in the same cacheline as the start of extlb */
    pgd_t *pgd __attribute__((aligned(0x80))); /* Current PGD */
    pgd_t *kernel_pgd;      /* Kernel PGD */
    /* We can have up to 3 levels of reentrancy in the TLB miss handler */
    u64 extlb[3][EX_TLB_SIZE / sizeof(u64)];
    u64 exmc[8];        /* used for machine checks */
    u64 excrit[8];      /* used for crit interrupts */
    u64 exdbg[8];       /* used for debug interrupts */

    /* Kernel stack pointers for use by special exceptions */
    void *mc_kstack;
    void *crit_kstack;
    void *dbg_kstack;
#endif /* CONFIG_PPC_BOOK3E */

    mm_context_t context;

    /*
     * then miscellaneous read-write fields
     */
    struct task_struct *__current;  /* Pointer to current */
    u64 kstack;         /* Saved Kernel stack addr */
    u64 stab_rr;            /* stab/slb round-robin counter */
    u64 saved_r1;           /* r1 save for RTAS calls or PM */
    u64 saved_msr;          /* MSR saved here by enter_rtas */
    u16 trap_save;          /* Used when bad stack is encountered */
    u8 soft_enabled;        /* irq soft-enable flag */
    u8 irq_happened;        /* irq happened while soft-disabled */
    u8 io_sync;         /* writel() needs spin_unlock sync */
    u8 irq_work_pending;        /* IRQ_WORK interrupt while soft-disable */
    u8 nap_state_lost;      /* NV GPR values lost in power7_idle */
    u64 sprg3;          /* Saved user-visible sprg */

#ifdef CONFIG_PPC_POWERNV
    /* Pointer to OPAL machine check event structure set by the
     * early exception handler for use by high level C handler
     */
    struct opal_machine_check_event *opal_mc_evt;
#endif

    /* Stuff for accurate time accounting */
    u64 user_time;          /* accumulated usermode TB ticks */
    u64 system_time;        /* accumulated system TB ticks */
    u64 user_time_scaled;       /* accumulated usermode SPURR ticks */
    u64 starttime;          /* TB value snapshot */
    u64 starttime_user;     /* TB value on exit to usermode */
    u64 startspurr;         /* SPURR value snapshot */
    u64 utime_sspurr;       /* ->user_time when ->startspurr set */
    u64 stolen_time;        /* TB ticks taken by hypervisor */
    u64 dtl_ridx;           /* read index in dispatch log */
    struct dtl_entry *dtl_curr; /* pointer corresponding to dtl_ridx */

#ifdef CONFIG_KVM_BOOK3S_HANDLER
#ifdef CONFIG_KVM_BOOK3S_PR
    /* We use this to store guest state in */
    struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
#endif
    struct kvmppc_host_state kvm_hstate;
#endif
};

extern struct paca_struct *paca;
extern __initdata struct paca_struct boot_paca;
extern void initialise_paca(struct paca_struct *new_paca, int cpu);
extern void setup_paca(struct paca_struct *new_paca);
extern void allocate_pacas(void);
extern void free_unused_pacas(void);

#else /* CONFIG_PPC64 */

static inline void allocate_pacas(void) { };
static inline void free_unused_pacas(void) { };

#endif /* CONFIG_PPC64 */

#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_PACA_H */