1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * c 2001 PPC 64 Team, IBM Corp
4 */
5
6 #include <linux/smp.h>
7 #include <linux/export.h>
8 #include <linux/memblock.h>
9 #include <linux/sched/task.h>
10 #include <linux/numa.h>
11
12 #include <asm/lppaca.h>
13 #include <asm/paca.h>
14 #include <asm/sections.h>
15 #include <asm/pgtable.h>
16 #include <asm/kexec.h>
17 #include <asm/svm.h>
18 #include <asm/ultravisor.h>
19
20 #include "setup.h"
21
22 #ifndef CONFIG_SMP
23 #define boot_cpuid 0
24 #endif
25
alloc_paca_data(unsigned long size,unsigned long align,unsigned long limit,int cpu)26 static void *__init alloc_paca_data(unsigned long size, unsigned long align,
27 unsigned long limit, int cpu)
28 {
29 void *ptr;
30 int nid;
31
32 /*
33 * boot_cpuid paca is allocated very early before cpu_to_node is up.
34 * Set bottom-up mode, because the boot CPU should be on node-0,
35 * which will put its paca in the right place.
36 */
37 if (cpu == boot_cpuid) {
38 nid = NUMA_NO_NODE;
39 memblock_set_bottom_up(true);
40 } else {
41 nid = early_cpu_to_node(cpu);
42 }
43
44 ptr = memblock_alloc_try_nid(size, align, MEMBLOCK_LOW_LIMIT,
45 limit, nid);
46 if (!ptr)
47 panic("cannot allocate paca data");
48
49 if (cpu == boot_cpuid)
50 memblock_set_bottom_up(false);
51
52 return ptr;
53 }
54
55 #ifdef CONFIG_PPC_PSERIES
56
57 #define LPPACA_SIZE 0x400
58
alloc_shared_lppaca(unsigned long size,unsigned long align,unsigned long limit,int cpu)59 static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
60 unsigned long limit, int cpu)
61 {
62 size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
63 static unsigned long shared_lppaca_size;
64 static void *shared_lppaca;
65 void *ptr;
66
67 if (!shared_lppaca) {
68 memblock_set_bottom_up(true);
69
70 shared_lppaca =
71 memblock_alloc_try_nid(shared_lppaca_total_size,
72 PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
73 limit, NUMA_NO_NODE);
74 if (!shared_lppaca)
75 panic("cannot allocate shared data");
76
77 memblock_set_bottom_up(false);
78 uv_share_page(PHYS_PFN(__pa(shared_lppaca)),
79 shared_lppaca_total_size >> PAGE_SHIFT);
80 }
81
82 ptr = shared_lppaca + shared_lppaca_size;
83 shared_lppaca_size += size;
84
85 /*
86 * This is very early in boot, so no harm done if the kernel crashes at
87 * this point.
88 */
89 BUG_ON(shared_lppaca_size > shared_lppaca_total_size);
90
91 return ptr;
92 }
93
94 /*
95 * See asm/lppaca.h for more detail.
96 *
97 * lppaca structures must must be 1kB in size, L1 cache line aligned,
98 * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
99 * these requirements.
100 */
init_lppaca(struct lppaca * lppaca)101 static inline void init_lppaca(struct lppaca *lppaca)
102 {
103 BUILD_BUG_ON(sizeof(struct lppaca) != 640);
104
105 *lppaca = (struct lppaca) {
106 .desc = cpu_to_be32(0xd397d781), /* "LpPa" */
107 .size = cpu_to_be16(LPPACA_SIZE),
108 .fpregs_in_use = 1,
109 .slb_count = cpu_to_be16(64),
110 .vmxregs_in_use = 0,
111 .page_ins = 0, };
112 };
113
new_lppaca(int cpu,unsigned long limit)114 static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
115 {
116 struct lppaca *lp;
117
118 BUILD_BUG_ON(sizeof(struct lppaca) > LPPACA_SIZE);
119
120 if (early_cpu_has_feature(CPU_FTR_HVMODE))
121 return NULL;
122
123 if (is_secure_guest())
124 lp = alloc_shared_lppaca(LPPACA_SIZE, 0x400, limit, cpu);
125 else
126 lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
127
128 init_lppaca(lp);
129
130 return lp;
131 }
132 #endif /* CONFIG_PPC_PSERIES */
133
134 #ifdef CONFIG_PPC_BOOK3S_64
135
136 /*
137 * 3 persistent SLBs are allocated here. The buffer will be zero
138 * initially, hence will all be invaild until we actually write them.
139 *
140 * If you make the number of persistent SLB entries dynamic, please also
141 * update PR KVM to flush and restore them accordingly.
142 */
new_slb_shadow(int cpu,unsigned long limit)143 static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit)
144 {
145 struct slb_shadow *s;
146
147 if (cpu != boot_cpuid) {
148 /*
149 * Boot CPU comes here before early_radix_enabled
150 * is parsed (e.g., for disable_radix). So allocate
151 * always and this will be fixed up in free_unused_pacas.
152 */
153 if (early_radix_enabled())
154 return NULL;
155 }
156
157 s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu);
158
159 s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
160 s->buffer_length = cpu_to_be32(sizeof(*s));
161
162 return s;
163 }
164
165 #endif /* CONFIG_PPC_BOOK3S_64 */
166
167 /* The Paca is an array with one entry per processor. Each contains an
168 * lppaca, which contains the information shared between the
169 * hypervisor and Linux.
170 * On systems with hardware multi-threading, there are two threads
171 * per processor. The Paca array must contain an entry for each thread.
172 * The VPD Areas will give a max logical processors = 2 * max physical
173 * processors. The processor VPD array needs one entry per physical
174 * processor (not thread).
175 */
176 struct paca_struct **paca_ptrs __read_mostly;
177 EXPORT_SYMBOL(paca_ptrs);
178
initialise_paca(struct paca_struct * new_paca,int cpu)179 void __init initialise_paca(struct paca_struct *new_paca, int cpu)
180 {
181 #ifdef CONFIG_PPC_PSERIES
182 new_paca->lppaca_ptr = NULL;
183 #endif
184 #ifdef CONFIG_PPC_BOOK3E
185 new_paca->kernel_pgd = swapper_pg_dir;
186 #endif
187 new_paca->lock_token = 0x8000;
188 new_paca->paca_index = cpu;
189 new_paca->kernel_toc = kernel_toc_addr();
190 new_paca->kernelbase = (unsigned long) _stext;
191 /* Only set MSR:IR/DR when MMU is initialized */
192 new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR);
193 new_paca->hw_cpu_id = 0xffff;
194 new_paca->kexec_state = KEXEC_STATE_NONE;
195 new_paca->__current = &init_task;
196 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
197 #ifdef CONFIG_PPC_BOOK3S_64
198 new_paca->slb_shadow_ptr = NULL;
199 #endif
200
201 #ifdef CONFIG_PPC_BOOK3E
202 /* For now -- if we have threads this will be adjusted later */
203 new_paca->tcd_ptr = &new_paca->tcd;
204 #endif
205 }
206
207 /* Put the paca pointer into r13 and SPRG_PACA */
setup_paca(struct paca_struct * new_paca)208 void setup_paca(struct paca_struct *new_paca)
209 {
210 /* Setup r13 */
211 local_paca = new_paca;
212
213 #ifdef CONFIG_PPC_BOOK3E
214 /* On Book3E, initialize the TLB miss exception frames */
215 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
216 #else
217 /*
218 * In HV mode, we setup both HPACA and PACA to avoid problems
219 * if we do a GET_PACA() before the feature fixups have been
220 * applied.
221 *
222 * Normally you should test against CPU_FTR_HVMODE, but CPU features
223 * are not yet set up when we first reach here.
224 */
225 if (mfmsr() & MSR_HV)
226 mtspr(SPRN_SPRG_HPACA, local_paca);
227 #endif
228 mtspr(SPRN_SPRG_PACA, local_paca);
229
230 }
231
232 static int __initdata paca_nr_cpu_ids;
233 static int __initdata paca_ptrs_size;
234 static int __initdata paca_struct_size;
235
allocate_paca_ptrs(void)236 void __init allocate_paca_ptrs(void)
237 {
238 paca_nr_cpu_ids = nr_cpu_ids;
239
240 paca_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
241 paca_ptrs = memblock_alloc_raw(paca_ptrs_size, SMP_CACHE_BYTES);
242 if (!paca_ptrs)
243 panic("Failed to allocate %d bytes for paca pointers\n",
244 paca_ptrs_size);
245
246 memset(paca_ptrs, 0x88, paca_ptrs_size);
247 }
248
allocate_paca(int cpu)249 void __init allocate_paca(int cpu)
250 {
251 u64 limit;
252 struct paca_struct *paca;
253
254 BUG_ON(cpu >= paca_nr_cpu_ids);
255
256 #ifdef CONFIG_PPC_BOOK3S_64
257 /*
258 * We access pacas in real mode, and cannot take SLB faults
259 * on them when in virtual mode, so allocate them accordingly.
260 */
261 limit = min(ppc64_bolted_size(), ppc64_rma_size);
262 #else
263 limit = ppc64_rma_size;
264 #endif
265
266 paca = alloc_paca_data(sizeof(struct paca_struct), L1_CACHE_BYTES,
267 limit, cpu);
268 paca_ptrs[cpu] = paca;
269
270 initialise_paca(paca, cpu);
271 #ifdef CONFIG_PPC_PSERIES
272 paca->lppaca_ptr = new_lppaca(cpu, limit);
273 #endif
274 #ifdef CONFIG_PPC_BOOK3S_64
275 paca->slb_shadow_ptr = new_slb_shadow(cpu, limit);
276 #endif
277 paca_struct_size += sizeof(struct paca_struct);
278 }
279
free_unused_pacas(void)280 void __init free_unused_pacas(void)
281 {
282 int new_ptrs_size;
283
284 new_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
285 if (new_ptrs_size < paca_ptrs_size)
286 memblock_free(__pa(paca_ptrs) + new_ptrs_size,
287 paca_ptrs_size - new_ptrs_size);
288
289 paca_nr_cpu_ids = nr_cpu_ids;
290 paca_ptrs_size = new_ptrs_size;
291
292 #ifdef CONFIG_PPC_BOOK3S_64
293 if (early_radix_enabled()) {
294 /* Ugly fixup, see new_slb_shadow() */
295 memblock_free(__pa(paca_ptrs[boot_cpuid]->slb_shadow_ptr),
296 sizeof(struct slb_shadow));
297 paca_ptrs[boot_cpuid]->slb_shadow_ptr = NULL;
298 }
299 #endif
300
301 printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
302 paca_ptrs_size + paca_struct_size, nr_cpu_ids);
303 }
304
copy_mm_to_paca(struct mm_struct * mm)305 void copy_mm_to_paca(struct mm_struct *mm)
306 {
307 #ifdef CONFIG_PPC_BOOK3S
308 mm_context_t *context = &mm->context;
309
310 get_paca()->mm_ctx_id = context->id;
311 #ifdef CONFIG_PPC_MM_SLICES
312 VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
313 get_paca()->mm_ctx_slb_addr_limit = mm_ctx_slb_addr_limit(context);
314 memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
315 LOW_SLICE_ARRAY_SZ);
316 memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
317 TASK_SLICE_ARRAY_SZ(context));
318 #else /* CONFIG_PPC_MM_SLICES */
319 get_paca()->mm_ctx_user_psize = context->user_psize;
320 get_paca()->mm_ctx_sllp = context->sllp;
321 #endif
322 #else /* !CONFIG_PPC_BOOK3S */
323 return;
324 #endif
325 }
326