xref: /openbmc/linux/arch/powerpc/include/asm/paca.h (revision 82df5b73)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * This control block defines the PACA which defines the processor
4  * specific data for each logical processor on the system.
5  * There are some pointers defined that are utilized by PLIC.
6  *
7  * C 2001 PPC 64 Team, IBM Corp
8  */
9 #ifndef _ASM_POWERPC_PACA_H
10 #define _ASM_POWERPC_PACA_H
11 #ifdef __KERNEL__
12 
13 #ifdef CONFIG_PPC64
14 
15 #include <linux/string.h>
16 #include <asm/types.h>
17 #include <asm/lppaca.h>
18 #include <asm/mmu.h>
19 #include <asm/page.h>
20 #ifdef CONFIG_PPC_BOOK3E
21 #include <asm/exception-64e.h>
22 #else
23 #include <asm/exception-64s.h>
24 #endif
25 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
26 #include <asm/kvm_book3s_asm.h>
27 #endif
28 #include <asm/accounting.h>
29 #include <asm/hmi.h>
30 #include <asm/cpuidle.h>
31 #include <asm/atomic.h>
32 #include <asm/rtas-types.h>
33 
34 #include <asm-generic/mmiowb_types.h>
35 
36 register struct paca_struct *local_paca asm("r13");
37 
38 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
39 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
40 /*
41  * Add standard checks that preemption cannot occur when using get_paca():
42  * otherwise the paca_struct it points to may be the wrong one just after.
43  */
44 #define get_paca()	((void) debug_smp_processor_id(), local_paca)
45 #else
46 #define get_paca()	local_paca
47 #endif
48 
49 #ifdef CONFIG_PPC_PSERIES
50 #define get_lppaca()	(get_paca()->lppaca_ptr)
51 #endif
52 
53 #define get_slb_shadow()	(get_paca()->slb_shadow_ptr)
54 
55 struct task_struct;
56 
57 /*
58  * Defines the layout of the paca.
59  *
60  * This structure is not directly accessed by firmware or the service
61  * processor.
62  */
63 struct paca_struct {
64 #ifdef CONFIG_PPC_PSERIES
65 	/*
66 	 * Because hw_cpu_id, unlike other paca fields, is accessed
67 	 * routinely from other CPUs (from the IRQ code), we stick to
68 	 * read-only (after boot) fields in the first cacheline to
69 	 * avoid cacheline bouncing.
70 	 */
71 
72 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
73 #endif /* CONFIG_PPC_PSERIES */
74 
75 	/*
76 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
77 	 * load lock_token and paca_index with a single lwz
78 	 * instruction.  They must travel together and be properly
79 	 * aligned.
80 	 */
81 #ifdef __BIG_ENDIAN__
82 	u16 lock_token;			/* Constant 0x8000, used in locks */
83 	u16 paca_index;			/* Logical processor number */
84 #else
85 	u16 paca_index;			/* Logical processor number */
86 	u16 lock_token;			/* Constant 0x8000, used in locks */
87 #endif
88 
89 	u64 kernel_toc;			/* Kernel TOC address */
90 	u64 kernelbase;			/* Base address of kernel */
91 	u64 kernel_msr;			/* MSR while running in kernel */
92 	void *emergency_sp;		/* pointer to emergency stack */
93 	u64 data_offset;		/* per cpu data offset */
94 	s16 hw_cpu_id;			/* Physical processor number */
95 	u8 cpu_start;			/* At startup, processor spins until */
96 					/* this becomes non-zero. */
97 	u8 kexec_state;		/* set when kexec down has irqs off */
98 #ifdef CONFIG_PPC_BOOK3S_64
99 	struct slb_shadow *slb_shadow_ptr;
100 	struct dtl_entry *dispatch_log;
101 	struct dtl_entry *dispatch_log_end;
102 #endif
103 	u64 dscr_default;		/* per-CPU default DSCR */
104 
105 #ifdef CONFIG_PPC_BOOK3S_64
106 	/*
107 	 * Now, starting in cacheline 2, the exception save areas
108 	 */
109 	/* used for most interrupts/exceptions */
110 	u64 exgen[EX_SIZE] __attribute__((aligned(0x80)));
111 	u64 exslb[EX_SIZE];	/* used for SLB/segment table misses
112  				 * on the linear mapping */
113 	/* SLB related definitions */
114 	u16 vmalloc_sllp;
115 	u8 slb_cache_ptr;
116 	u8 stab_rr;			/* stab/slb round-robin counter */
117 #ifdef CONFIG_DEBUG_VM
118 	u8 in_kernel_slb_handler;
119 #endif
120 	u32 slb_used_bitmap;		/* Bitmaps for first 32 SLB entries. */
121 	u32 slb_kern_bitmap;
122 	u32 slb_cache[SLB_CACHE_ENTRIES];
123 #endif /* CONFIG_PPC_BOOK3S_64 */
124 
125 #ifdef CONFIG_PPC_BOOK3E
126 	u64 exgen[8] __aligned(0x40);
127 	/* Keep pgd in the same cacheline as the start of extlb */
128 	pgd_t *pgd __aligned(0x40); /* Current PGD */
129 	pgd_t *kernel_pgd;		/* Kernel PGD */
130 
131 	/* Shared by all threads of a core -- points to tcd of first thread */
132 	struct tlb_core_data *tcd_ptr;
133 
134 	/*
135 	 * We can have up to 3 levels of reentrancy in the TLB miss handler,
136 	 * in each of four exception levels (normal, crit, mcheck, debug).
137 	 */
138 	u64 extlb[12][EX_TLB_SIZE / sizeof(u64)];
139 	u64 exmc[8];		/* used for machine checks */
140 	u64 excrit[8];		/* used for crit interrupts */
141 	u64 exdbg[8];		/* used for debug interrupts */
142 
143 	/* Kernel stack pointers for use by special exceptions */
144 	void *mc_kstack;
145 	void *crit_kstack;
146 	void *dbg_kstack;
147 
148 	struct tlb_core_data tcd;
149 #endif /* CONFIG_PPC_BOOK3E */
150 
151 #ifdef CONFIG_PPC_BOOK3S
152 	mm_context_id_t mm_ctx_id;
153 #ifdef CONFIG_PPC_MM_SLICES
154 	unsigned char mm_ctx_low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
155 	unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
156 	unsigned long mm_ctx_slb_addr_limit;
157 #else
158 	u16 mm_ctx_user_psize;
159 	u16 mm_ctx_sllp;
160 #endif
161 #endif
162 
163 	/*
164 	 * then miscellaneous read-write fields
165 	 */
166 	struct task_struct *__current;	/* Pointer to current */
167 	u64 kstack;			/* Saved Kernel stack addr */
168 	u64 saved_r1;			/* r1 save for RTAS calls or PM or EE=0 */
169 	u64 saved_msr;			/* MSR saved here by enter_rtas */
170 #ifdef CONFIG_PPC_BOOK3E
171 	u16 trap_save;			/* Used when bad stack is encountered */
172 #endif
173 	u8 irq_soft_mask;		/* mask for irq soft masking */
174 	u8 irq_happened;		/* irq happened while soft-disabled */
175 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
176 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
177 	u8 pmcregs_in_use;		/* pseries puts this in lppaca */
178 #endif
179 	u64 sprg_vdso;			/* Saved user-visible sprg */
180 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
181 	u64 tm_scratch;                 /* TM scratch area for reclaim */
182 #endif
183 
184 #ifdef CONFIG_PPC_POWERNV
185 	/* PowerNV idle fields */
186 	/* PNV_CORE_IDLE_* bits, all siblings work on thread 0 paca */
187 	unsigned long idle_state;
188 	union {
189 		/* P7/P8 specific fields */
190 		struct {
191 			/* PNV_THREAD_RUNNING/NAP/SLEEP	*/
192 			u8 thread_idle_state;
193 			/* Mask to denote subcore sibling threads */
194 			u8 subcore_sibling_mask;
195 		};
196 
197 		/* P9 specific fields */
198 		struct {
199 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
200 			/* The PSSCR value that the kernel requested before going to stop */
201 			u64 requested_psscr;
202 			/* Flag to request this thread not to stop */
203 			atomic_t dont_stop;
204 #endif
205 		};
206 	};
207 #endif
208 
209 #ifdef CONFIG_PPC_BOOK3S_64
210 	/* Non-maskable exceptions that are not performance critical */
211 	u64 exnmi[EX_SIZE];	/* used for system reset (nmi) */
212 	u64 exmc[EX_SIZE];	/* used for machine checks */
213 #endif
214 #ifdef CONFIG_PPC_BOOK3S_64
215 	/* Exclusive stacks for system reset and machine check exception. */
216 	void *nmi_emergency_sp;
217 	void *mc_emergency_sp;
218 
219 	u16 in_nmi;			/* In nmi handler */
220 
221 	/*
222 	 * Flag to check whether we are in machine check early handler
223 	 * and already using emergency stack.
224 	 */
225 	u16 in_mce;
226 	u8 hmi_event_available;		/* HMI event is available */
227 	u8 hmi_p9_special_emu;		/* HMI P9 special emulation */
228 #endif
229 	u8 ftrace_enabled;		/* Hard disable ftrace */
230 
231 	/* Stuff for accurate time accounting */
232 	struct cpu_accounting_data accounting;
233 	u64 dtl_ridx;			/* read index in dispatch log */
234 	struct dtl_entry *dtl_curr;	/* pointer corresponding to dtl_ridx */
235 
236 #ifdef CONFIG_KVM_BOOK3S_HANDLER
237 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
238 	/* We use this to store guest state in */
239 	struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
240 #endif
241 	struct kvmppc_host_state kvm_hstate;
242 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
243 	/*
244 	 * Bitmap for sibling subcore status. See kvm/book3s_hv_ras.c for
245 	 * more details
246 	 */
247 	struct sibling_subcore_state *sibling_subcore_state;
248 #endif
249 #endif
250 #ifdef CONFIG_PPC_BOOK3S_64
251 	/*
252 	 * rfi fallback flush must be in its own cacheline to prevent
253 	 * other paca data leaking into the L1d
254 	 */
255 	u64 exrfi[EX_SIZE] __aligned(0x80);
256 	void *rfi_flush_fallback_area;
257 	u64 l1d_flush_size;
258 #endif
259 #ifdef CONFIG_PPC_PSERIES
260 	struct rtas_args *rtas_args_reentrant;
261 	u8 *mce_data_buf;		/* buffer to hold per cpu rtas errlog */
262 #endif /* CONFIG_PPC_PSERIES */
263 
264 #ifdef CONFIG_PPC_BOOK3S_64
265 	/* Capture SLB related old contents in MCE handler. */
266 	struct slb_entry *mce_faulty_slbs;
267 	u16 slb_save_cache_ptr;
268 #endif /* CONFIG_PPC_BOOK3S_64 */
269 #ifdef CONFIG_STACKPROTECTOR
270 	unsigned long canary;
271 #endif
272 #ifdef CONFIG_MMIOWB
273 	struct mmiowb_state mmiowb_state;
274 #endif
275 } ____cacheline_aligned;
276 
277 extern void copy_mm_to_paca(struct mm_struct *mm);
278 extern struct paca_struct **paca_ptrs;
279 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
280 extern void setup_paca(struct paca_struct *new_paca);
281 extern void allocate_paca_ptrs(void);
282 extern void allocate_paca(int cpu);
283 extern void free_unused_pacas(void);
284 
285 #else /* CONFIG_PPC64 */
286 
287 static inline void allocate_paca_ptrs(void) { };
288 static inline void allocate_paca(int cpu) { };
289 static inline void free_unused_pacas(void) { };
290 
291 #endif /* CONFIG_PPC64 */
292 
293 #endif /* __KERNEL__ */
294 #endif /* _ASM_POWERPC_PACA_H */
295