xref: /openbmc/linux/arch/powerpc/include/asm/paca.h (revision 64d85cc9)
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 
33 #include <asm-generic/mmiowb_types.h>
34 
35 register struct paca_struct *local_paca asm("r13");
36 
37 #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
38 extern unsigned int debug_smp_processor_id(void); /* from linux/smp.h */
39 /*
40  * Add standard checks that preemption cannot occur when using get_paca():
41  * otherwise the paca_struct it points to may be the wrong one just after.
42  */
43 #define get_paca()	((void) debug_smp_processor_id(), local_paca)
44 #else
45 #define get_paca()	local_paca
46 #endif
47 
48 #ifdef CONFIG_PPC_PSERIES
49 #define get_lppaca()	(get_paca()->lppaca_ptr)
50 #endif
51 
52 #define get_slb_shadow()	(get_paca()->slb_shadow_ptr)
53 
54 struct task_struct;
55 
56 /*
57  * Defines the layout of the paca.
58  *
59  * This structure is not directly accessed by firmware or the service
60  * processor.
61  */
62 struct paca_struct {
63 #ifdef CONFIG_PPC_PSERIES
64 	/*
65 	 * Because hw_cpu_id, unlike other paca fields, is accessed
66 	 * routinely from other CPUs (from the IRQ code), we stick to
67 	 * read-only (after boot) fields in the first cacheline to
68 	 * avoid cacheline bouncing.
69 	 */
70 
71 	struct lppaca *lppaca_ptr;	/* Pointer to LpPaca for PLIC */
72 #endif /* CONFIG_PPC_PSERIES */
73 
74 	/*
75 	 * MAGIC: the spinlock functions in arch/powerpc/lib/locks.c
76 	 * load lock_token and paca_index with a single lwz
77 	 * instruction.  They must travel together and be properly
78 	 * aligned.
79 	 */
80 #ifdef __BIG_ENDIAN__
81 	u16 lock_token;			/* Constant 0x8000, used in locks */
82 	u16 paca_index;			/* Logical processor number */
83 #else
84 	u16 paca_index;			/* Logical processor number */
85 	u16 lock_token;			/* Constant 0x8000, used in locks */
86 #endif
87 
88 	u64 kernel_toc;			/* Kernel TOC address */
89 	u64 kernelbase;			/* Base address of kernel */
90 	u64 kernel_msr;			/* MSR while running in kernel */
91 	void *emergency_sp;		/* pointer to emergency stack */
92 	u64 data_offset;		/* per cpu data offset */
93 	s16 hw_cpu_id;			/* Physical processor number */
94 	u8 cpu_start;			/* At startup, processor spins until */
95 					/* this becomes non-zero. */
96 	u8 kexec_state;		/* set when kexec down has irqs off */
97 #ifdef CONFIG_PPC_BOOK3S_64
98 	struct slb_shadow *slb_shadow_ptr;
99 	struct dtl_entry *dispatch_log;
100 	struct dtl_entry *dispatch_log_end;
101 #endif
102 	u64 dscr_default;		/* per-CPU default DSCR */
103 
104 #ifdef CONFIG_PPC_BOOK3S_64
105 	/*
106 	 * Now, starting in cacheline 2, the exception save areas
107 	 */
108 	/* used for most interrupts/exceptions */
109 	u64 exgen[EX_SIZE] __attribute__((aligned(0x80)));
110 	u64 exslb[EX_SIZE];	/* used for SLB/segment table misses
111  				 * on the linear mapping */
112 	/* SLB related definitions */
113 	u16 vmalloc_sllp;
114 	u8 slb_cache_ptr;
115 	u8 stab_rr;			/* stab/slb round-robin counter */
116 #ifdef CONFIG_DEBUG_VM
117 	u8 in_kernel_slb_handler;
118 #endif
119 	u32 slb_used_bitmap;		/* Bitmaps for first 32 SLB entries. */
120 	u32 slb_kern_bitmap;
121 	u32 slb_cache[SLB_CACHE_ENTRIES];
122 #endif /* CONFIG_PPC_BOOK3S_64 */
123 
124 #ifdef CONFIG_PPC_BOOK3E
125 	u64 exgen[8] __aligned(0x40);
126 	/* Keep pgd in the same cacheline as the start of extlb */
127 	pgd_t *pgd __aligned(0x40); /* Current PGD */
128 	pgd_t *kernel_pgd;		/* Kernel PGD */
129 
130 	/* Shared by all threads of a core -- points to tcd of first thread */
131 	struct tlb_core_data *tcd_ptr;
132 
133 	/*
134 	 * We can have up to 3 levels of reentrancy in the TLB miss handler,
135 	 * in each of four exception levels (normal, crit, mcheck, debug).
136 	 */
137 	u64 extlb[12][EX_TLB_SIZE / sizeof(u64)];
138 	u64 exmc[8];		/* used for machine checks */
139 	u64 excrit[8];		/* used for crit interrupts */
140 	u64 exdbg[8];		/* used for debug interrupts */
141 
142 	/* Kernel stack pointers for use by special exceptions */
143 	void *mc_kstack;
144 	void *crit_kstack;
145 	void *dbg_kstack;
146 
147 	struct tlb_core_data tcd;
148 #endif /* CONFIG_PPC_BOOK3E */
149 
150 #ifdef CONFIG_PPC_BOOK3S
151 	mm_context_id_t mm_ctx_id;
152 #ifdef CONFIG_PPC_MM_SLICES
153 	unsigned char mm_ctx_low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
154 	unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
155 	unsigned long mm_ctx_slb_addr_limit;
156 #else
157 	u16 mm_ctx_user_psize;
158 	u16 mm_ctx_sllp;
159 #endif
160 #endif
161 
162 	/*
163 	 * then miscellaneous read-write fields
164 	 */
165 	struct task_struct *__current;	/* Pointer to current */
166 	u64 kstack;			/* Saved Kernel stack addr */
167 	u64 saved_r1;			/* r1 save for RTAS calls or PM or EE=0 */
168 	u64 saved_msr;			/* MSR saved here by enter_rtas */
169 	u16 trap_save;			/* Used when bad stack is encountered */
170 	u8 irq_soft_mask;		/* mask for irq soft masking */
171 	u8 irq_happened;		/* irq happened while soft-disabled */
172 	u8 irq_work_pending;		/* IRQ_WORK interrupt while soft-disable */
173 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
174 	u8 pmcregs_in_use;		/* pseries puts this in lppaca */
175 #endif
176 	u64 sprg_vdso;			/* Saved user-visible sprg */
177 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
178 	u64 tm_scratch;                 /* TM scratch area for reclaim */
179 #endif
180 
181 #ifdef CONFIG_PPC_POWERNV
182 	/* PowerNV idle fields */
183 	/* PNV_CORE_IDLE_* bits, all siblings work on thread 0 paca */
184 	unsigned long idle_state;
185 	union {
186 		/* P7/P8 specific fields */
187 		struct {
188 			/* PNV_THREAD_RUNNING/NAP/SLEEP	*/
189 			u8 thread_idle_state;
190 			/* Mask to denote subcore sibling threads */
191 			u8 subcore_sibling_mask;
192 		};
193 
194 		/* P9 specific fields */
195 		struct {
196 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
197 			/* The PSSCR value that the kernel requested before going to stop */
198 			u64 requested_psscr;
199 			/* Flag to request this thread not to stop */
200 			atomic_t dont_stop;
201 #endif
202 		};
203 	};
204 #endif
205 
206 #ifdef CONFIG_PPC_BOOK3S_64
207 	/* Non-maskable exceptions that are not performance critical */
208 	u64 exnmi[EX_SIZE];	/* used for system reset (nmi) */
209 	u64 exmc[EX_SIZE];	/* used for machine checks */
210 #endif
211 #ifdef CONFIG_PPC_BOOK3S_64
212 	/* Exclusive stacks for system reset and machine check exception. */
213 	void *nmi_emergency_sp;
214 	void *mc_emergency_sp;
215 
216 	u16 in_nmi;			/* In nmi handler */
217 
218 	/*
219 	 * Flag to check whether we are in machine check early handler
220 	 * and already using emergency stack.
221 	 */
222 	u16 in_mce;
223 	u8 hmi_event_available;		/* HMI event is available */
224 	u8 hmi_p9_special_emu;		/* HMI P9 special emulation */
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 	u8 *mce_data_buf;		/* buffer to hold per cpu rtas errlog */
258 #endif /* CONFIG_PPC_PSERIES */
259 
260 #ifdef CONFIG_PPC_BOOK3S_64
261 	/* Capture SLB related old contents in MCE handler. */
262 	struct slb_entry *mce_faulty_slbs;
263 	u16 slb_save_cache_ptr;
264 #endif /* CONFIG_PPC_BOOK3S_64 */
265 #ifdef CONFIG_STACKPROTECTOR
266 	unsigned long canary;
267 #endif
268 #ifdef CONFIG_MMIOWB
269 	struct mmiowb_state mmiowb_state;
270 #endif
271 } ____cacheline_aligned;
272 
273 extern void copy_mm_to_paca(struct mm_struct *mm);
274 extern struct paca_struct **paca_ptrs;
275 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
276 extern void setup_paca(struct paca_struct *new_paca);
277 extern void allocate_paca_ptrs(void);
278 extern void allocate_paca(int cpu);
279 extern void free_unused_pacas(void);
280 
281 #else /* CONFIG_PPC64 */
282 
283 static inline void allocate_paca_ptrs(void) { };
284 static inline void allocate_paca(int cpu) { };
285 static inline void free_unused_pacas(void) { };
286 
287 #endif /* CONFIG_PPC64 */
288 
289 #endif /* __KERNEL__ */
290 #endif /* _ASM_POWERPC_PACA_H */
291