xref: /openbmc/linux/arch/powerpc/include/asm/paca.h (revision 6fa24b41)
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/cache.h>
16 #include <linux/string.h>
17 #include <asm/types.h>
18 #include <asm/mmu.h>
19 #include <asm/page.h>
20 #ifdef CONFIG_PPC_BOOK3E_64
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/mce.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 #define get_slb_shadow()	(get_paca()->slb_shadow_ptr)
50 
51 struct task_struct;
52 struct rtas_args;
53 struct lppaca;
54 
55 /*
56  * Defines the layout of the paca.
57  *
58  * This structure is not directly accessed by firmware or the service
59  * processor.
60  */
61 struct paca_struct {
62 #ifdef CONFIG_PPC_PSERIES
63 	/*
64 	 * Because hw_cpu_id, unlike other paca fields, is accessed
65 	 * routinely from other CPUs (from the IRQ code), we stick to
66 	 * read-only (after boot) fields in the first cacheline to
67 	 * avoid cacheline bouncing.
68 	 */
69 
70 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
71 #endif /* CONFIG_PPC_PSERIES */
72 
73 	/*
74 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
75 	 * load lock_token and paca_index with a single lwz
76 	 * instruction.  They must travel together and be properly
77 	 * aligned.
78 	 */
79 #ifdef __BIG_ENDIAN__
80 	u16 lock_token;			/* Constant 0x8000, used in locks */
81 	u16 paca_index;			/* Logical processor number */
82 #else
83 	u16 paca_index;			/* Logical processor number */
84 	u16 lock_token;			/* Constant 0x8000, used in locks */
85 #endif
86 
87 #ifndef CONFIG_PPC_KERNEL_PCREL
88 	u64 kernel_toc;			/* Kernel TOC address */
89 #endif
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 #ifdef CONFIG_PPC_64S_HASH_MMU
100 	struct slb_shadow *slb_shadow_ptr;
101 #endif
102 	struct dtl_entry *dispatch_log;
103 	struct dtl_entry *dispatch_log_end;
104 #endif
105 	u64 dscr_default;		/* per-CPU default DSCR */
106 
107 #ifdef CONFIG_PPC_BOOK3S_64
108 	/*
109 	 * Now, starting in cacheline 2, the exception save areas
110 	 */
111 	/* used for most interrupts/exceptions */
112 	u64 exgen[EX_SIZE] __attribute__((aligned(0x80)));
113 
114 #ifdef CONFIG_PPC_64S_HASH_MMU
115 	/* SLB related definitions */
116 	u16 vmalloc_sllp;
117 	u8 slb_cache_ptr;
118 	u8 stab_rr;			/* stab/slb round-robin counter */
119 #ifdef CONFIG_DEBUG_VM
120 	u8 in_kernel_slb_handler;
121 #endif
122 	u32 slb_used_bitmap;		/* Bitmaps for first 32 SLB entries. */
123 	u32 slb_kern_bitmap;
124 	u32 slb_cache[SLB_CACHE_ENTRIES];
125 #endif
126 #endif /* CONFIG_PPC_BOOK3S_64 */
127 
128 #ifdef CONFIG_PPC_BOOK3E_64
129 	u64 exgen[8] __aligned(0x40);
130 	/* Keep pgd in the same cacheline as the start of extlb */
131 	pgd_t *pgd __aligned(0x40); /* Current PGD */
132 	pgd_t *kernel_pgd;		/* Kernel PGD */
133 
134 	/* Shared by all threads of a core -- points to tcd of first thread */
135 	struct tlb_core_data *tcd_ptr;
136 
137 	/*
138 	 * We can have up to 3 levels of reentrancy in the TLB miss handler,
139 	 * in each of four exception levels (normal, crit, mcheck, debug).
140 	 */
141 	u64 extlb[12][EX_TLB_SIZE / sizeof(u64)];
142 	u64 exmc[8];		/* used for machine checks */
143 	u64 excrit[8];		/* used for crit interrupts */
144 	u64 exdbg[8];		/* used for debug interrupts */
145 
146 	/* Kernel stack pointers for use by special exceptions */
147 	void *mc_kstack;
148 	void *crit_kstack;
149 	void *dbg_kstack;
150 
151 	struct tlb_core_data tcd;
152 #endif /* CONFIG_PPC_BOOK3E_64 */
153 
154 #ifdef CONFIG_PPC_64S_HASH_MMU
155 	unsigned char mm_ctx_low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
156 	unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
157 #endif
158 
159 	/*
160 	 * then miscellaneous read-write fields
161 	 */
162 	struct task_struct *__current;	/* Pointer to current */
163 	u64 kstack;			/* Saved Kernel stack addr */
164 	u64 saved_r1;			/* r1 save for RTAS calls or PM or EE=0 */
165 	u64 saved_msr;			/* MSR saved here by enter_rtas */
166 #ifdef CONFIG_PPC64
167 	u64 exit_save_r1;		/* Syscall/interrupt R1 save */
168 #endif
169 #ifdef CONFIG_PPC_BOOK3E_64
170 	u16 trap_save;			/* Used when bad stack is encountered */
171 #endif
172 #ifdef CONFIG_PPC_BOOK3S_64
173 	u8 hsrr_valid;			/* HSRRs set for HRFID */
174 	u8 srr_valid;			/* SRRs set for RFID */
175 #endif
176 	u8 irq_soft_mask;		/* mask for irq soft masking */
177 	u8 irq_happened;		/* irq happened while soft-disabled */
178 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
179 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
180 	u8 pmcregs_in_use;		/* pseries puts this in lppaca */
181 #endif
182 	u64 sprg_vdso;			/* Saved user-visible sprg */
183 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
184 	u64 tm_scratch;                 /* TM scratch area for reclaim */
185 #endif
186 
187 #ifdef CONFIG_PPC_POWERNV
188 	/* PowerNV idle fields */
189 	/* PNV_CORE_IDLE_* bits, all siblings work on thread 0 paca */
190 	unsigned long idle_lock; /* A value of 1 means acquired */
191 	unsigned long idle_state;
192 	union {
193 		/* P7/P8 specific fields */
194 		struct {
195 			/* PNV_THREAD_RUNNING/NAP/SLEEP	*/
196 			u8 thread_idle_state;
197 			/* Mask to denote subcore sibling threads */
198 			u8 subcore_sibling_mask;
199 		};
200 
201 		/* P9 specific fields */
202 		struct {
203 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
204 			/* The PSSCR value that the kernel requested before going to stop */
205 			u64 requested_psscr;
206 			/* Flag to request this thread not to stop */
207 			atomic_t dont_stop;
208 #endif
209 		};
210 	};
211 #endif
212 
213 #ifdef CONFIG_PPC_BOOK3S_64
214 	/* Non-maskable exceptions that are not performance critical */
215 	u64 exnmi[EX_SIZE];	/* used for system reset (nmi) */
216 	u64 exmc[EX_SIZE];	/* used for machine checks */
217 #endif
218 #ifdef CONFIG_PPC_BOOK3S_64
219 	/* Exclusive stacks for system reset and machine check exception. */
220 	void *nmi_emergency_sp;
221 	void *mc_emergency_sp;
222 
223 	u16 in_nmi;			/* In nmi handler */
224 
225 	/*
226 	 * Flag to check whether we are in machine check early handler
227 	 * and already using emergency stack.
228 	 */
229 	u16 in_mce;
230 	u8 hmi_event_available;		/* HMI event is available */
231 	u8 hmi_p9_special_emu;		/* HMI P9 special emulation */
232 	u32 hmi_irqs;			/* HMI irq stat */
233 #endif
234 	u8 ftrace_enabled;		/* Hard disable ftrace */
235 
236 	/* Stuff for accurate time accounting */
237 	struct cpu_accounting_data accounting;
238 	u64 dtl_ridx;			/* read index in dispatch log */
239 	struct dtl_entry *dtl_curr;	/* pointer corresponding to dtl_ridx */
240 
241 #ifdef CONFIG_KVM_BOOK3S_HANDLER
242 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
243 	/* We use this to store guest state in */
244 	struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
245 #endif
246 	struct kvmppc_host_state kvm_hstate;
247 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
248 	/*
249 	 * Bitmap for sibling subcore status. See kvm/book3s_hv_ras.c for
250 	 * more details
251 	 */
252 	struct sibling_subcore_state *sibling_subcore_state;
253 #endif
254 #endif
255 #ifdef CONFIG_PPC_BOOK3S_64
256 	/*
257 	 * rfi fallback flush must be in its own cacheline to prevent
258 	 * other paca data leaking into the L1d
259 	 */
260 	u64 exrfi[EX_SIZE] __aligned(0x80);
261 	void *rfi_flush_fallback_area;
262 	u64 l1d_flush_size;
263 #endif
264 #ifdef CONFIG_PPC_PSERIES
265 	u8 *mce_data_buf;		/* buffer to hold per cpu rtas errlog */
266 #endif /* CONFIG_PPC_PSERIES */
267 
268 #ifdef CONFIG_PPC_BOOK3S_64
269 #ifdef CONFIG_PPC_64S_HASH_MMU
270 	/* Capture SLB related old contents in MCE handler. */
271 	struct slb_entry *mce_faulty_slbs;
272 	u16 slb_save_cache_ptr;
273 #endif
274 #endif /* CONFIG_PPC_BOOK3S_64 */
275 #ifdef CONFIG_STACKPROTECTOR
276 	unsigned long canary;
277 #endif
278 #ifdef CONFIG_MMIOWB
279 	struct mmiowb_state mmiowb_state;
280 #endif
281 #ifdef CONFIG_PPC_BOOK3S_64
282 	struct mce_info *mce_info;
283 	u8 mce_pending_irq_work;
284 #endif /* CONFIG_PPC_BOOK3S_64 */
285 } ____cacheline_aligned;
286 
287 extern void copy_mm_to_paca(struct mm_struct *mm);
288 extern struct paca_struct **paca_ptrs;
289 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
290 extern void setup_paca(struct paca_struct *new_paca);
291 extern void allocate_paca_ptrs(void);
292 extern void allocate_paca(int cpu);
293 extern void free_unused_pacas(void);
294 
295 #else /* CONFIG_PPC64 */
296 
297 static inline void allocate_paca(int cpu) { }
298 static inline void free_unused_pacas(void) { }
299 
300 #endif /* CONFIG_PPC64 */
301 
302 #endif /* __KERNEL__ */
303 #endif /* _ASM_POWERPC_PACA_H */
304