xref: /linux/arch/powerpc/include/asm/paca.h (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 #ifdef CONFIG_PPC64
18 
19 #include <linux/init.h>
20 #include <asm/types.h>
21 #include <asm/lppaca.h>
22 #include <asm/mmu.h>
23 #include <asm/page.h>
24 #include <asm/exception-64e.h>
25 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
26 #include <asm/kvm_book3s_asm.h>
27 #endif
28 
29 register struct paca_struct *local_paca asm("r13");
30 
31 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
32 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
33 /*
34  * Add standard checks that preemption cannot occur when using get_paca():
35  * otherwise the paca_struct it points to may be the wrong one just after.
36  */
37 #define get_paca()	((void) debug_smp_processor_id(), local_paca)
38 #else
39 #define get_paca()	local_paca
40 #endif
41 
42 #define get_lppaca()	(get_paca()->lppaca_ptr)
43 #define get_slb_shadow()	(get_paca()->slb_shadow_ptr)
44 
45 struct task_struct;
46 struct opal_machine_check_event;
47 
48 /*
49  * Defines the layout of the paca.
50  *
51  * This structure is not directly accessed by firmware or the service
52  * processor.
53  */
54 struct paca_struct {
55 #ifdef CONFIG_PPC_BOOK3S
56 	/*
57 	 * Because hw_cpu_id, unlike other paca fields, is accessed
58 	 * routinely from other CPUs (from the IRQ code), we stick to
59 	 * read-only (after boot) fields in the first cacheline to
60 	 * avoid cacheline bouncing.
61 	 */
62 
63 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
64 #endif /* CONFIG_PPC_BOOK3S */
65 	/*
66 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
67 	 * load lock_token and paca_index with a single lwz
68 	 * instruction.  They must travel together and be properly
69 	 * aligned.
70 	 */
71 #ifdef __BIG_ENDIAN__
72 	u16 lock_token;			/* Constant 0x8000, used in locks */
73 	u16 paca_index;			/* Logical processor number */
74 #else
75 	u16 paca_index;			/* Logical processor number */
76 	u16 lock_token;			/* Constant 0x8000, used in locks */
77 #endif
78 
79 	u64 kernel_toc;			/* Kernel TOC address */
80 	u64 kernelbase;			/* Base address of kernel */
81 	u64 kernel_msr;			/* MSR while running in kernel */
82 #ifdef CONFIG_PPC_STD_MMU_64
83 	u64 stab_real;			/* Absolute address of segment table */
84 	u64 stab_addr;			/* Virtual address of segment table */
85 #endif /* CONFIG_PPC_STD_MMU_64 */
86 	void *emergency_sp;		/* pointer to emergency stack */
87 	u64 data_offset;		/* per cpu data offset */
88 	s16 hw_cpu_id;			/* Physical processor number */
89 	u8 cpu_start;			/* At startup, processor spins until */
90 					/* this becomes non-zero. */
91 	u8 kexec_state;		/* set when kexec down has irqs off */
92 #ifdef CONFIG_PPC_STD_MMU_64
93 	struct slb_shadow *slb_shadow_ptr;
94 	struct dtl_entry *dispatch_log;
95 	struct dtl_entry *dispatch_log_end;
96 
97 	/*
98 	 * Now, starting in cacheline 2, the exception save areas
99 	 */
100 	/* used for most interrupts/exceptions */
101 	u64 exgen[13] __attribute__((aligned(0x80)));
102 	u64 exmc[13];		/* used for machine checks */
103 	u64 exslb[13];		/* used for SLB/segment table misses
104  				 * on the linear mapping */
105 	/* SLB related definitions */
106 	u16 vmalloc_sllp;
107 	u16 slb_cache_ptr;
108 	u32 slb_cache[SLB_CACHE_ENTRIES];
109 #endif /* CONFIG_PPC_STD_MMU_64 */
110 
111 #ifdef CONFIG_PPC_BOOK3E
112 	u64 exgen[8] __attribute__((aligned(0x80)));
113 	/* Keep pgd in the same cacheline as the start of extlb */
114 	pgd_t *pgd __attribute__((aligned(0x80))); /* Current PGD */
115 	pgd_t *kernel_pgd;		/* Kernel PGD */
116 	/* We can have up to 3 levels of reentrancy in the TLB miss handler */
117 	u64 extlb[3][EX_TLB_SIZE / sizeof(u64)];
118 	u64 exmc[8];		/* used for machine checks */
119 	u64 excrit[8];		/* used for crit interrupts */
120 	u64 exdbg[8];		/* used for debug interrupts */
121 
122 	/* Kernel stack pointers for use by special exceptions */
123 	void *mc_kstack;
124 	void *crit_kstack;
125 	void *dbg_kstack;
126 #endif /* CONFIG_PPC_BOOK3E */
127 
128 	mm_context_t context;
129 
130 	/*
131 	 * then miscellaneous read-write fields
132 	 */
133 	struct task_struct *__current;	/* Pointer to current */
134 	u64 kstack;			/* Saved Kernel stack addr */
135 	u64 stab_rr;			/* stab/slb round-robin counter */
136 	u64 saved_r1;			/* r1 save for RTAS calls or PM */
137 	u64 saved_msr;			/* MSR saved here by enter_rtas */
138 	u16 trap_save;			/* Used when bad stack is encountered */
139 	u8 soft_enabled;		/* irq soft-enable flag */
140 	u8 irq_happened;		/* irq happened while soft-disabled */
141 	u8 io_sync;			/* writel() needs spin_unlock sync */
142 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
143 	u8 nap_state_lost;		/* NV GPR values lost in power7_idle */
144 	u64 sprg3;			/* Saved user-visible sprg */
145 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
146 	u64 tm_scratch;                 /* TM scratch area for reclaim */
147 #endif
148 
149 #ifdef CONFIG_PPC_POWERNV
150 	/* Pointer to OPAL machine check event structure set by the
151 	 * early exception handler for use by high level C handler
152 	 */
153 	struct opal_machine_check_event *opal_mc_evt;
154 #endif
155 
156 	/* Stuff for accurate time accounting */
157 	u64 user_time;			/* accumulated usermode TB ticks */
158 	u64 system_time;		/* accumulated system TB ticks */
159 	u64 user_time_scaled;		/* accumulated usermode SPURR ticks */
160 	u64 starttime;			/* TB value snapshot */
161 	u64 starttime_user;		/* TB value on exit to usermode */
162 	u64 startspurr;			/* SPURR value snapshot */
163 	u64 utime_sspurr;		/* ->user_time when ->startspurr set */
164 	u64 stolen_time;		/* TB ticks taken by hypervisor */
165 	u64 dtl_ridx;			/* read index in dispatch log */
166 	struct dtl_entry *dtl_curr;	/* pointer corresponding to dtl_ridx */
167 
168 #ifdef CONFIG_KVM_BOOK3S_HANDLER
169 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
170 	/* We use this to store guest state in */
171 	struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
172 #endif
173 	struct kvmppc_host_state kvm_hstate;
174 #endif
175 };
176 
177 extern struct paca_struct *paca;
178 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
179 extern void setup_paca(struct paca_struct *new_paca);
180 extern void allocate_pacas(void);
181 extern void free_unused_pacas(void);
182 
183 #else /* CONFIG_PPC64 */
184 
185 static inline void allocate_pacas(void) { };
186 static inline void free_unused_pacas(void) { };
187 
188 #endif /* CONFIG_PPC64 */
189 
190 #endif /* __KERNEL__ */
191 #endif /* _ASM_POWERPC_PACA_H */
192