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2 * c 2001 PPC 64 Team, IBM Corp
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
10 #include <linux/smp.h>
11 #include <linux/export.h>
12 #include <linux/memblock.h>
13 #include <linux/sched/task.h>
15 #include <asm/lppaca.h>
17 #include <asm/sections.h>
18 #include <asm/pgtable.h>
19 #include <asm/kexec.h>
21 #ifdef CONFIG_PPC_BOOK3S
24 * The structure which the hypervisor knows about - this structure
25 * should not cross a page boundary. The vpa_init/register_vpa call
26 * is now known to fail if the lppaca structure crosses a page
27 * boundary. The lppaca is also used on POWER5 pSeries boxes.
28 * The lppaca is 640 bytes long, and cannot readily
29 * change since the hypervisor knows its layout, so a 1kB alignment
30 * will suffice to ensure that it doesn't cross a page boundary.
32 struct lppaca lppaca
[] = {
33 [0 ... (NR_LPPACAS
-1)] = {
34 .desc
= cpu_to_be32(0xd397d781), /* "LpPa" */
35 .size
= cpu_to_be16(sizeof(struct lppaca
)),
37 .slb_count
= cpu_to_be16(64),
43 static struct lppaca
*extra_lppacas
;
44 static long __initdata lppaca_size
;
46 static void __init
allocate_lppacas(int nr_cpus
, unsigned long limit
)
48 if (nr_cpus
<= NR_LPPACAS
)
51 lppaca_size
= PAGE_ALIGN(sizeof(struct lppaca
) *
52 (nr_cpus
- NR_LPPACAS
));
53 extra_lppacas
= __va(memblock_alloc_base(lppaca_size
,
57 static struct lppaca
* __init
new_lppaca(int cpu
)
64 lp
= extra_lppacas
+ (cpu
- NR_LPPACAS
);
70 static void __init
free_lppacas(void)
72 long new_size
= 0, nr
;
76 nr
= num_possible_cpus() - NR_LPPACAS
;
78 new_size
= PAGE_ALIGN(nr
* sizeof(struct lppaca
));
79 if (new_size
>= lppaca_size
)
82 memblock_free(__pa(extra_lppacas
) + new_size
, lppaca_size
- new_size
);
83 lppaca_size
= new_size
;
88 static inline void allocate_lppacas(int nr_cpus
, unsigned long limit
) { }
89 static inline void free_lppacas(void) { }
91 #endif /* CONFIG_PPC_BOOK3S */
93 #ifdef CONFIG_PPC_BOOK3S_64
96 * 3 persistent SLBs are registered here. The buffer will be zero
97 * initially, hence will all be invaild until we actually write them.
99 * If you make the number of persistent SLB entries dynamic, please also
100 * update PR KVM to flush and restore them accordingly.
102 static struct slb_shadow
* __initdata slb_shadow
;
104 static void __init
allocate_slb_shadows(int nr_cpus
, int limit
)
106 int size
= PAGE_ALIGN(sizeof(struct slb_shadow
) * nr_cpus
);
108 if (early_radix_enabled())
111 slb_shadow
= __va(memblock_alloc_base(size
, PAGE_SIZE
, limit
));
112 memset(slb_shadow
, 0, size
);
115 static struct slb_shadow
* __init
init_slb_shadow(int cpu
)
117 struct slb_shadow
*s
;
119 if (early_radix_enabled())
122 s
= &slb_shadow
[cpu
];
125 * When we come through here to initialise boot_paca, the slb_shadow
126 * buffers are not allocated yet. That's OK, we'll get one later in
127 * boot, but make sure we don't corrupt memory at 0.
132 s
->persistent
= cpu_to_be32(SLB_NUM_BOLTED
);
133 s
->buffer_length
= cpu_to_be32(sizeof(*s
));
138 #else /* !CONFIG_PPC_BOOK3S_64 */
140 static void __init
allocate_slb_shadows(int nr_cpus
, int limit
) { }
142 #endif /* CONFIG_PPC_BOOK3S_64 */
144 /* The Paca is an array with one entry per processor. Each contains an
145 * lppaca, which contains the information shared between the
146 * hypervisor and Linux.
147 * On systems with hardware multi-threading, there are two threads
148 * per processor. The Paca array must contain an entry for each thread.
149 * The VPD Areas will give a max logical processors = 2 * max physical
150 * processors. The processor VPD array needs one entry per physical
151 * processor (not thread).
153 struct paca_struct
*paca
;
156 void __init
initialise_paca(struct paca_struct
*new_paca
, int cpu
)
158 #ifdef CONFIG_PPC_BOOK3S
159 new_paca
->lppaca_ptr
= new_lppaca(cpu
);
161 new_paca
->kernel_pgd
= swapper_pg_dir
;
163 new_paca
->lock_token
= 0x8000;
164 new_paca
->paca_index
= cpu
;
165 new_paca
->kernel_toc
= kernel_toc_addr();
166 new_paca
->kernelbase
= (unsigned long) _stext
;
167 /* Only set MSR:IR/DR when MMU is initialized */
168 new_paca
->kernel_msr
= MSR_KERNEL
& ~(MSR_IR
| MSR_DR
);
169 new_paca
->hw_cpu_id
= 0xffff;
170 new_paca
->kexec_state
= KEXEC_STATE_NONE
;
171 new_paca
->__current
= &init_task
;
172 new_paca
->data_offset
= 0xfeeeeeeeeeeeeeeeULL
;
173 #ifdef CONFIG_PPC_BOOK3S_64
174 new_paca
->slb_shadow_ptr
= init_slb_shadow(cpu
);
177 #ifdef CONFIG_PPC_BOOK3E
178 /* For now -- if we have threads this will be adjusted later */
179 new_paca
->tcd_ptr
= &new_paca
->tcd
;
183 /* Put the paca pointer into r13 and SPRG_PACA */
184 void setup_paca(struct paca_struct
*new_paca
)
187 local_paca
= new_paca
;
189 #ifdef CONFIG_PPC_BOOK3E
190 /* On Book3E, initialize the TLB miss exception frames */
191 mtspr(SPRN_SPRG_TLB_EXFRAME
, local_paca
->extlb
);
193 /* In HV mode, we setup both HPACA and PACA to avoid problems
194 * if we do a GET_PACA() before the feature fixups have been
197 if (early_cpu_has_feature(CPU_FTR_HVMODE
))
198 mtspr(SPRN_SPRG_HPACA
, local_paca
);
200 mtspr(SPRN_SPRG_PACA
, local_paca
);
204 static int __initdata paca_size
;
206 void __init
allocate_pacas(void)
210 unsigned int nr_cpus
;
212 limit
= ppc64_rma_size
;
214 #ifdef CONFIG_PPC_BOOK3S_64
216 * We can't take SLB misses on the paca, and we want to access them
217 * in real mode, so allocate them within the RMA and also within
220 limit
= min(0x10000000ULL
, limit
);
224 * Always align up the nr_cpu_ids to SMT threads and allocate
225 * the paca. This will help us to prepare for a situation where
226 * boot cpu id > nr_cpus_id. We will use the last nthreads
227 * slots (nthreads == threads per core) to accommodate a core
228 * that contains boot cpu thread.
230 * Do not change nr_cpu_ids value here. Let us do that in
231 * early_init_dt_scan_cpus() where we know exact value
232 * of threads per core.
234 nr_cpus
= _ALIGN_UP(nr_cpu_ids
, MAX_SMT
);
235 paca_size
= PAGE_ALIGN(sizeof(struct paca_struct
) * nr_cpus
);
237 paca
= __va(memblock_alloc_base(paca_size
, PAGE_SIZE
, limit
));
238 memset(paca
, 0, paca_size
);
240 printk(KERN_DEBUG
"Allocated %u bytes for %u pacas at %p\n",
241 paca_size
, nr_cpus
, paca
);
243 allocate_lppacas(nr_cpus
, limit
);
245 allocate_slb_shadows(nr_cpus
, limit
);
247 /* Can't use for_each_*_cpu, as they aren't functional yet */
248 for (cpu
= 0; cpu
< nr_cpus
; cpu
++)
249 initialise_paca(&paca
[cpu
], cpu
);
252 void __init
free_unused_pacas(void)
256 new_size
= PAGE_ALIGN(sizeof(struct paca_struct
) * nr_cpu_ids
);
258 if (new_size
>= paca_size
)
261 memblock_free(__pa(paca
) + new_size
, paca_size
- new_size
);
263 printk(KERN_DEBUG
"Freed %u bytes for unused pacas\n",
264 paca_size
- new_size
);
266 paca_size
= new_size
;
271 void copy_mm_to_paca(struct mm_struct
*mm
)
273 #ifdef CONFIG_PPC_BOOK3S
274 mm_context_t
*context
= &mm
->context
;
276 get_paca()->mm_ctx_id
= context
->id
;
277 #ifdef CONFIG_PPC_MM_SLICES
278 VM_BUG_ON(!mm
->context
.slb_addr_limit
);
279 get_paca()->mm_ctx_slb_addr_limit
= mm
->context
.slb_addr_limit
;
280 get_paca()->mm_ctx_low_slices_psize
= context
->low_slices_psize
;
281 memcpy(&get_paca()->mm_ctx_high_slices_psize
,
282 &context
->high_slices_psize
, TASK_SLICE_ARRAY_SZ(mm
));
283 #else /* CONFIG_PPC_MM_SLICES */
284 get_paca()->mm_ctx_user_psize
= context
->user_psize
;
285 get_paca()->mm_ctx_sllp
= context
->sllp
;
287 #else /* !CONFIG_PPC_BOOK3S */