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/mmu.h>
18 #include <asm/page.h>
19 #ifdef CONFIG_PPC_BOOK3E
20 #include <asm/exception-64e.h>
21 #else
22 #include <asm/exception-64s.h>
23 #endif
24 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
25 #include <asm/kvm_book3s_asm.h>
26 #endif
27 #include <asm/accounting.h>
28 #include <asm/hmi.h>
29 #include <asm/cpuidle.h>
30 #include <asm/atomic.h>
31 
32 #include <asm-generic/mmiowb_types.h>
33 
34 register struct paca_struct *local_paca asm("r13");
35 
36 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
37 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
38 /*
39  * Add standard checks that preemption cannot occur when using get_paca():
40  * otherwise the paca_struct it points to may be the wrong one just after.
41  */
42 #define get_paca()	((void) debug_smp_processor_id(), local_paca)
43 #else
44 #define get_paca()	local_paca
45 #endif
46 
47 #define get_slb_shadow()	(get_paca()->slb_shadow_ptr)
48 
49 struct task_struct;
50 struct rtas_args;
51 struct lppaca;
52 
53 /*
54  * Defines the layout of the paca.
55  *
56  * This structure is not directly accessed by firmware or the service
57  * processor.
58  */
59 struct paca_struct {
60 #ifdef CONFIG_PPC_PSERIES
61 	/*
62 	 * Because hw_cpu_id, unlike other paca fields, is accessed
63 	 * routinely from other CPUs (from the IRQ code), we stick to
64 	 * read-only (after boot) fields in the first cacheline to
65 	 * avoid cacheline bouncing.
66 	 */
67 
68 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
69 #endif /* CONFIG_PPC_PSERIES */
70 
71 	/*
72 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
73 	 * load lock_token and paca_index with a single lwz
74 	 * instruction.  They must travel together and be properly
75 	 * aligned.
76 	 */
77 #ifdef __BIG_ENDIAN__
78 	u16 lock_token;			/* Constant 0x8000, used in locks */
79 	u16 paca_index;			/* Logical processor number */
80 #else
81 	u16 paca_index;			/* Logical processor number */
82 	u16 lock_token;			/* Constant 0x8000, used in locks */
83 #endif
84 
85 	u64 kernel_toc;			/* Kernel TOC address */
86 	u64 kernelbase;			/* Base address of kernel */
87 	u64 kernel_msr;			/* MSR while running in kernel */
88 	void *emergency_sp;		/* pointer to emergency stack */
89 	u64 data_offset;		/* per cpu data offset */
90 	s16 hw_cpu_id;			/* Physical processor number */
91 	u8 cpu_start;			/* At startup, processor spins until */
92 					/* this becomes non-zero. */
93 	u8 kexec_state;		/* set when kexec down has irqs off */
94 #ifdef CONFIG_PPC_BOOK3S_64
95 	struct slb_shadow *slb_shadow_ptr;
96 	struct dtl_entry *dispatch_log;
97 	struct dtl_entry *dispatch_log_end;
98 #endif
99 	u64 dscr_default;		/* per-CPU default DSCR */
100 
101 #ifdef CONFIG_PPC_BOOK3S_64
102 	/*
103 	 * Now, starting in cacheline 2, the exception save areas
104 	 */
105 	/* used for most interrupts/exceptions */
106 	u64 exgen[EX_SIZE] __attribute__((aligned(0x80)));
107 	u64 exslb[EX_SIZE];	/* used for SLB/segment table misses
108  				 * on the linear mapping */
109 	/* SLB related definitions */
110 	u16 vmalloc_sllp;
111 	u8 slb_cache_ptr;
112 	u8 stab_rr;			/* stab/slb round-robin counter */
113 #ifdef CONFIG_DEBUG_VM
114 	u8 in_kernel_slb_handler;
115 #endif
116 	u32 slb_used_bitmap;		/* Bitmaps for first 32 SLB entries. */
117 	u32 slb_kern_bitmap;
118 	u32 slb_cache[SLB_CACHE_ENTRIES];
119 #endif /* CONFIG_PPC_BOOK3S_64 */
120 
121 #ifdef CONFIG_PPC_BOOK3E
122 	u64 exgen[8] __aligned(0x40);
123 	/* Keep pgd in the same cacheline as the start of extlb */
124 	pgd_t *pgd __aligned(0x40); /* Current PGD */
125 	pgd_t *kernel_pgd;		/* Kernel PGD */
126 
127 	/* Shared by all threads of a core -- points to tcd of first thread */
128 	struct tlb_core_data *tcd_ptr;
129 
130 	/*
131 	 * We can have up to 3 levels of reentrancy in the TLB miss handler,
132 	 * in each of four exception levels (normal, crit, mcheck, debug).
133 	 */
134 	u64 extlb[12][EX_TLB_SIZE / sizeof(u64)];
135 	u64 exmc[8];		/* used for machine checks */
136 	u64 excrit[8];		/* used for crit interrupts */
137 	u64 exdbg[8];		/* used for debug interrupts */
138 
139 	/* Kernel stack pointers for use by special exceptions */
140 	void *mc_kstack;
141 	void *crit_kstack;
142 	void *dbg_kstack;
143 
144 	struct tlb_core_data tcd;
145 #endif /* CONFIG_PPC_BOOK3E */
146 
147 #ifdef CONFIG_PPC_BOOK3S
148 	mm_context_id_t mm_ctx_id;
149 #ifdef CONFIG_PPC_MM_SLICES
150 	unsigned char mm_ctx_low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
151 	unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
152 	unsigned long mm_ctx_slb_addr_limit;
153 #else
154 	u16 mm_ctx_user_psize;
155 	u16 mm_ctx_sllp;
156 #endif
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_PPC_BOOK3E
167 	u16 trap_save;			/* Used when bad stack is encountered */
168 #endif
169 	u8 irq_soft_mask;		/* mask for irq soft masking */
170 	u8 irq_happened;		/* irq happened while soft-disabled */
171 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
172 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
173 	u8 pmcregs_in_use;		/* pseries puts this in lppaca */
174 #endif
175 	u64 sprg_vdso;			/* Saved user-visible sprg */
176 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
177 	u64 tm_scratch;                 /* TM scratch area for reclaim */
178 #endif
179 
180 #ifdef CONFIG_PPC_POWERNV
181 	/* PowerNV idle fields */
182 	/* PNV_CORE_IDLE_* bits, all siblings work on thread 0 paca */
183 	unsigned long idle_state;
184 	union {
185 		/* P7/P8 specific fields */
186 		struct {
187 			/* PNV_THREAD_RUNNING/NAP/SLEEP	*/
188 			u8 thread_idle_state;
189 			/* Mask to denote subcore sibling threads */
190 			u8 subcore_sibling_mask;
191 		};
192 
193 		/* P9 specific fields */
194 		struct {
195 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
196 			/* The PSSCR value that the kernel requested before going to stop */
197 			u64 requested_psscr;
198 			/* Flag to request this thread not to stop */
199 			atomic_t dont_stop;
200 #endif
201 		};
202 	};
203 #endif
204 
205 #ifdef CONFIG_PPC_BOOK3S_64
206 	/* Non-maskable exceptions that are not performance critical */
207 	u64 exnmi[EX_SIZE];	/* used for system reset (nmi) */
208 	u64 exmc[EX_SIZE];	/* used for machine checks */
209 #endif
210 #ifdef CONFIG_PPC_BOOK3S_64
211 	/* Exclusive stacks for system reset and machine check exception. */
212 	void *nmi_emergency_sp;
213 	void *mc_emergency_sp;
214 
215 	u16 in_nmi;			/* In nmi handler */
216 
217 	/*
218 	 * Flag to check whether we are in machine check early handler
219 	 * and already using emergency stack.
220 	 */
221 	u16 in_mce;
222 	u8 hmi_event_available;		/* HMI event is available */
223 	u8 hmi_p9_special_emu;		/* HMI P9 special emulation */
224 	u32 hmi_irqs;			/* HMI irq stat */
225 #endif
226 	u8 ftrace_enabled;		/* Hard disable ftrace */
227 
228 	/* Stuff for accurate time accounting */
229 	struct cpu_accounting_data accounting;
230 	u64 dtl_ridx;			/* read index in dispatch log */
231 	struct dtl_entry *dtl_curr;	/* pointer corresponding to dtl_ridx */
232 
233 #ifdef CONFIG_KVM_BOOK3S_HANDLER
234 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
235 	/* We use this to store guest state in */
236 	struct kvmppc_book3s_shadow_vcpu shadow_vcpu;
237 #endif
238 	struct kvmppc_host_state kvm_hstate;
239 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
240 	/*
241 	 * Bitmap for sibling subcore status. See kvm/book3s_hv_ras.c for
242 	 * more details
243 	 */
244 	struct sibling_subcore_state *sibling_subcore_state;
245 #endif
246 #endif
247 #ifdef CONFIG_PPC_BOOK3S_64
248 	/*
249 	 * rfi fallback flush must be in its own cacheline to prevent
250 	 * other paca data leaking into the L1d
251 	 */
252 	u64 exrfi[EX_SIZE] __aligned(0x80);
253 	void *rfi_flush_fallback_area;
254 	u64 l1d_flush_size;
255 #endif
256 #ifdef CONFIG_PPC_PSERIES
257 	struct rtas_args *rtas_args_reentrant;
258 	u8 *mce_data_buf;		/* buffer to hold per cpu rtas errlog */
259 #endif /* CONFIG_PPC_PSERIES */
260 
261 #ifdef CONFIG_PPC_BOOK3S_64
262 	/* Capture SLB related old contents in MCE handler. */
263 	struct slb_entry *mce_faulty_slbs;
264 	u16 slb_save_cache_ptr;
265 #endif /* CONFIG_PPC_BOOK3S_64 */
266 #ifdef CONFIG_STACKPROTECTOR
267 	unsigned long canary;
268 #endif
269 #ifdef CONFIG_MMIOWB
270 	struct mmiowb_state mmiowb_state;
271 #endif
272 } ____cacheline_aligned;
273 
274 extern void copy_mm_to_paca(struct mm_struct *mm);
275 extern struct paca_struct **paca_ptrs;
276 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
277 extern void setup_paca(struct paca_struct *new_paca);
278 extern void allocate_paca_ptrs(void);
279 extern void allocate_paca(int cpu);
280 extern void free_unused_pacas(void);
281 
282 #else /* CONFIG_PPC64 */
283 
allocate_paca_ptrs(void)284 static inline void allocate_paca_ptrs(void) { };
allocate_paca(int cpu)285 static inline void allocate_paca(int cpu) { };
free_unused_pacas(void)286 static inline void free_unused_pacas(void) { };
287 
288 #endif /* CONFIG_PPC64 */
289 
290 #endif /* __KERNEL__ */
291 #endif /* _ASM_POWERPC_PACA_H */
292