xref: /openbmc/linux/arch/powerpc/include/asm/paca.h (revision e8e0929d)
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 #include <asm/page.h>
21 #include <asm/exception-64e.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.
46  */
47 struct paca_struct {
48 #ifdef CONFIG_PPC_BOOK3S
49 	/*
50 	 * Because hw_cpu_id, unlike other paca fields, is accessed
51 	 * routinely from other CPUs (from the IRQ code), we stick to
52 	 * read-only (after boot) fields in the first cacheline to
53 	 * avoid cacheline bouncing.
54 	 */
55 
56 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
57 #endif /* CONFIG_PPC_BOOK3S */
58 	/*
59 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
60 	 * load lock_token and paca_index with a single lwz
61 	 * instruction.  They must travel together and be properly
62 	 * aligned.
63 	 */
64 	u16 lock_token;			/* Constant 0x8000, used in locks */
65 	u16 paca_index;			/* Logical processor number */
66 
67 	u64 kernel_toc;			/* Kernel TOC address */
68 	u64 kernelbase;			/* Base address of kernel */
69 	u64 kernel_msr;			/* MSR while running in kernel */
70 #ifdef CONFIG_PPC_STD_MMU_64
71 	u64 stab_real;			/* Absolute address of segment table */
72 	u64 stab_addr;			/* Virtual address of segment table */
73 #endif /* CONFIG_PPC_STD_MMU_64 */
74 	void *emergency_sp;		/* pointer to emergency stack */
75 	u64 data_offset;		/* per cpu data offset */
76 	s16 hw_cpu_id;			/* Physical processor number */
77 	u8 cpu_start;			/* At startup, processor spins until */
78 					/* this becomes non-zero. */
79 #ifdef CONFIG_PPC_STD_MMU_64
80 	struct slb_shadow *slb_shadow_ptr;
81 
82 	/*
83 	 * Now, starting in cacheline 2, the exception save areas
84 	 */
85 	/* used for most interrupts/exceptions */
86 	u64 exgen[10] __attribute__((aligned(0x80)));
87 	u64 exmc[10];		/* used for machine checks */
88 	u64 exslb[10];		/* used for SLB/segment table misses
89  				 * on the linear mapping */
90 	/* SLB related definitions */
91 	u16 vmalloc_sllp;
92 	u16 slb_cache_ptr;
93 	u16 slb_cache[SLB_CACHE_ENTRIES];
94 #endif /* CONFIG_PPC_STD_MMU_64 */
95 
96 #ifdef CONFIG_PPC_BOOK3E
97 	pgd_t *pgd;			/* Current PGD */
98 	pgd_t *kernel_pgd;		/* Kernel PGD */
99 	u64 exgen[8] __attribute__((aligned(0x80)));
100 	u64 extlb[EX_TLB_SIZE*3] __attribute__((aligned(0x80)));
101 	u64 exmc[8];		/* used for machine checks */
102 	u64 excrit[8];		/* used for crit interrupts */
103 	u64 exdbg[8];		/* used for debug interrupts */
104 
105 	/* Kernel stack pointers for use by special exceptions */
106 	void *mc_kstack;
107 	void *crit_kstack;
108 	void *dbg_kstack;
109 #endif /* CONFIG_PPC_BOOK3E */
110 
111 	mm_context_t context;
112 
113 	/*
114 	 * then miscellaneous read-write fields
115 	 */
116 	struct task_struct *__current;	/* Pointer to current */
117 	u64 kstack;			/* Saved Kernel stack addr */
118 	u64 stab_rr;			/* stab/slb round-robin counter */
119 	u64 saved_r1;			/* r1 save for RTAS calls */
120 	u64 saved_msr;			/* MSR saved here by enter_rtas */
121 	u16 trap_save;			/* Used when bad stack is encountered */
122 	u8 soft_enabled;		/* irq soft-enable flag */
123 	u8 hard_enabled;		/* set if irqs are enabled in MSR */
124 	u8 io_sync;			/* writel() needs spin_unlock sync */
125 	u8 perf_event_pending;		/* PM interrupt while soft-disabled */
126 
127 	/* Stuff for accurate time accounting */
128 	u64 user_time;			/* accumulated usermode TB ticks */
129 	u64 system_time;		/* accumulated system TB ticks */
130 	u64 startpurr;			/* PURR/TB value snapshot */
131 	u64 startspurr;			/* SPURR value snapshot */
132 };
133 
134 extern struct paca_struct paca[];
135 extern void initialise_pacas(void);
136 
137 #endif /* __KERNEL__ */
138 #endif /* _ASM_POWERPC_PACA_H */
139