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 #include <linux/pgtable.h>
12
13 #include <asm/lppaca.h>
14 #include <asm/paca.h>
15 #include <asm/sections.h>
16 #include <asm/kexec.h>
17 #include <asm/svm.h>
18 #include <asm/ultravisor.h>
19 #include <asm/rtas.h>
20
21 #include "setup.h"
22
23 #ifndef CONFIG_SMP
24 #define boot_cpuid 0
25 #endif
26
alloc_paca_data(unsigned long size,unsigned long align,unsigned long limit,int cpu)27 static void *__init alloc_paca_data(unsigned long size, unsigned long align,
28 unsigned long limit, int cpu)
29 {
30 void *ptr;
31 int nid;
32
33 /*
34 * boot_cpuid paca is allocated very early before cpu_to_node is up.
35 * Set bottom-up mode, because the boot CPU should be on node-0,
36 * which will put its paca in the right place.
37 */
38 if (cpu == boot_cpuid) {
39 nid = NUMA_NO_NODE;
40 memblock_set_bottom_up(true);
41 } else {
42 nid = early_cpu_to_node(cpu);
43 }
44
45 ptr = memblock_alloc_try_nid(size, align, MEMBLOCK_LOW_LIMIT,
46 limit, nid);
47 if (!ptr)
48 panic("cannot allocate paca data");
49
50 if (cpu == boot_cpuid)
51 memblock_set_bottom_up(false);
52
53 return ptr;
54 }
55
56 #ifdef CONFIG_PPC_PSERIES
57
58 #define LPPACA_SIZE 0x400
59
alloc_shared_lppaca(unsigned long size,unsigned long limit,int cpu)60 static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit,
61 int cpu)
62 {
63 size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
64 static unsigned long shared_lppaca_size;
65 static void *shared_lppaca;
66 void *ptr;
67
68 if (!shared_lppaca) {
69 memblock_set_bottom_up(true);
70
71 /*
72 * See Documentation/powerpc/ultravisor.rst for more details.
73 *
74 * UV/HV data sharing is in PAGE_SIZE granularity. In order to
75 * minimize the number of pages shared, align the allocation to
76 * PAGE_SIZE.
77 */
78 shared_lppaca =
79 memblock_alloc_try_nid(shared_lppaca_total_size,
80 PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
81 limit, NUMA_NO_NODE);
82 if (!shared_lppaca)
83 panic("cannot allocate shared data");
84
85 memblock_set_bottom_up(false);
86 uv_share_page(PHYS_PFN(__pa(shared_lppaca)),
87 shared_lppaca_total_size >> PAGE_SHIFT);
88 }
89
90 ptr = shared_lppaca + shared_lppaca_size;
91 shared_lppaca_size += size;
92
93 /*
94 * This is very early in boot, so no harm done if the kernel crashes at
95 * this point.
96 */
97 BUG_ON(shared_lppaca_size > shared_lppaca_total_size);
98
99 return ptr;
100 }
101
102 /*
103 * See asm/lppaca.h for more detail.
104 *
105 * lppaca structures must must be 1kB in size, L1 cache line aligned,
106 * and not cross 4kB boundary. A 1kB size and 1kB alignment will satisfy
107 * these requirements.
108 */
init_lppaca(struct lppaca * lppaca)109 static inline void init_lppaca(struct lppaca *lppaca)
110 {
111 BUILD_BUG_ON(sizeof(struct lppaca) != 640);
112
113 *lppaca = (struct lppaca) {
114 .desc = cpu_to_be32(0xd397d781), /* "LpPa" */
115 .size = cpu_to_be16(LPPACA_SIZE),
116 .fpregs_in_use = 1,
117 .slb_count = cpu_to_be16(64),
118 .vmxregs_in_use = 0,
119 .page_ins = 0, };
120 };
121
new_lppaca(int cpu,unsigned long limit)122 static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
123 {
124 struct lppaca *lp;
125
126 BUILD_BUG_ON(sizeof(struct lppaca) > LPPACA_SIZE);
127
128 if (early_cpu_has_feature(CPU_FTR_HVMODE))
129 return NULL;
130
131 if (is_secure_guest())
132 lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu);
133 else
134 lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
135
136 init_lppaca(lp);
137
138 return lp;
139 }
140 #endif /* CONFIG_PPC_PSERIES */
141
142 #ifdef CONFIG_PPC_BOOK3S_64
143
144 /*
145 * 3 persistent SLBs are allocated here. The buffer will be zero
146 * initially, hence will all be invaild until we actually write them.
147 *
148 * If you make the number of persistent SLB entries dynamic, please also
149 * update PR KVM to flush and restore them accordingly.
150 */
new_slb_shadow(int cpu,unsigned long limit)151 static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit)
152 {
153 struct slb_shadow *s;
154
155 if (cpu != boot_cpuid) {
156 /*
157 * Boot CPU comes here before early_radix_enabled
158 * is parsed (e.g., for disable_radix). So allocate
159 * always and this will be fixed up in free_unused_pacas.
160 */
161 if (early_radix_enabled())
162 return NULL;
163 }
164
165 s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu);
166
167 s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
168 s->buffer_length = cpu_to_be32(sizeof(*s));
169
170 return s;
171 }
172
173 #endif /* CONFIG_PPC_BOOK3S_64 */
174
175 #ifdef CONFIG_PPC_PSERIES
176 /**
177 * new_rtas_args() - Allocates rtas args
178 * @cpu: CPU number
179 * @limit: Memory limit for this allocation
180 *
181 * Allocates a struct rtas_args and return it's pointer,
182 * if not in Hypervisor mode
183 *
184 * Return: Pointer to allocated rtas_args
185 * NULL if CPU in Hypervisor Mode
186 */
new_rtas_args(int cpu,unsigned long limit)187 static struct rtas_args * __init new_rtas_args(int cpu, unsigned long limit)
188 {
189 limit = min_t(unsigned long, limit, RTAS_INSTANTIATE_MAX);
190
191 if (early_cpu_has_feature(CPU_FTR_HVMODE))
192 return NULL;
193
194 return alloc_paca_data(sizeof(struct rtas_args), L1_CACHE_BYTES,
195 limit, cpu);
196 }
197 #endif /* CONFIG_PPC_PSERIES */
198
199 /* The Paca is an array with one entry per processor. Each contains an
200 * lppaca, which contains the information shared between the
201 * hypervisor and Linux.
202 * On systems with hardware multi-threading, there are two threads
203 * per processor. The Paca array must contain an entry for each thread.
204 * The VPD Areas will give a max logical processors = 2 * max physical
205 * processors. The processor VPD array needs one entry per physical
206 * processor (not thread).
207 */
208 struct paca_struct **paca_ptrs __read_mostly;
209 EXPORT_SYMBOL(paca_ptrs);
210
initialise_paca(struct paca_struct * new_paca,int cpu)211 void __init initialise_paca(struct paca_struct *new_paca, int cpu)
212 {
213 #ifdef CONFIG_PPC_PSERIES
214 new_paca->lppaca_ptr = NULL;
215 #endif
216 #ifdef CONFIG_PPC_BOOK3E
217 new_paca->kernel_pgd = swapper_pg_dir;
218 #endif
219 new_paca->lock_token = 0x8000;
220 new_paca->paca_index = cpu;
221 new_paca->kernel_toc = kernel_toc_addr();
222 new_paca->kernelbase = (unsigned long) _stext;
223 /* Only set MSR:IR/DR when MMU is initialized */
224 new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR);
225 new_paca->hw_cpu_id = 0xffff;
226 new_paca->kexec_state = KEXEC_STATE_NONE;
227 new_paca->__current = &init_task;
228 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL;
229 #ifdef CONFIG_PPC_BOOK3S_64
230 new_paca->slb_shadow_ptr = NULL;
231 #endif
232
233 #ifdef CONFIG_PPC_BOOK3E
234 /* For now -- if we have threads this will be adjusted later */
235 new_paca->tcd_ptr = &new_paca->tcd;
236 #endif
237
238 #ifdef CONFIG_PPC_PSERIES
239 new_paca->rtas_args_reentrant = NULL;
240 #endif
241 }
242
243 /* Put the paca pointer into r13 and SPRG_PACA */
setup_paca(struct paca_struct * new_paca)244 void setup_paca(struct paca_struct *new_paca)
245 {
246 /* Setup r13 */
247 local_paca = new_paca;
248
249 #ifdef CONFIG_PPC_BOOK3E
250 /* On Book3E, initialize the TLB miss exception frames */
251 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
252 #else
253 /*
254 * In HV mode, we setup both HPACA and PACA to avoid problems
255 * if we do a GET_PACA() before the feature fixups have been
256 * applied.
257 *
258 * Normally you should test against CPU_FTR_HVMODE, but CPU features
259 * are not yet set up when we first reach here.
260 */
261 if (mfmsr() & MSR_HV)
262 mtspr(SPRN_SPRG_HPACA, local_paca);
263 #endif
264 mtspr(SPRN_SPRG_PACA, local_paca);
265
266 }
267
268 static int __initdata paca_nr_cpu_ids;
269 static int __initdata paca_ptrs_size;
270 static int __initdata paca_struct_size;
271
allocate_paca_ptrs(void)272 void __init allocate_paca_ptrs(void)
273 {
274 paca_nr_cpu_ids = nr_cpu_ids;
275
276 paca_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
277 paca_ptrs = memblock_alloc_raw(paca_ptrs_size, SMP_CACHE_BYTES);
278 if (!paca_ptrs)
279 panic("Failed to allocate %d bytes for paca pointers\n",
280 paca_ptrs_size);
281
282 memset(paca_ptrs, 0x88, paca_ptrs_size);
283 }
284
allocate_paca(int cpu)285 void __init allocate_paca(int cpu)
286 {
287 u64 limit;
288 struct paca_struct *paca;
289
290 BUG_ON(cpu >= paca_nr_cpu_ids);
291
292 #ifdef CONFIG_PPC_BOOK3S_64
293 /*
294 * We access pacas in real mode, and cannot take SLB faults
295 * on them when in virtual mode, so allocate them accordingly.
296 */
297 limit = min(ppc64_bolted_size(), ppc64_rma_size);
298 #else
299 limit = ppc64_rma_size;
300 #endif
301
302 paca = alloc_paca_data(sizeof(struct paca_struct), L1_CACHE_BYTES,
303 limit, cpu);
304 paca_ptrs[cpu] = paca;
305
306 initialise_paca(paca, cpu);
307 #ifdef CONFIG_PPC_PSERIES
308 paca->lppaca_ptr = new_lppaca(cpu, limit);
309 #endif
310 #ifdef CONFIG_PPC_BOOK3S_64
311 paca->slb_shadow_ptr = new_slb_shadow(cpu, limit);
312 #endif
313 #ifdef CONFIG_PPC_PSERIES
314 paca->rtas_args_reentrant = new_rtas_args(cpu, limit);
315 #endif
316 paca_struct_size += sizeof(struct paca_struct);
317 }
318
free_unused_pacas(void)319 void __init free_unused_pacas(void)
320 {
321 int new_ptrs_size;
322
323 new_ptrs_size = sizeof(struct paca_struct *) * nr_cpu_ids;
324 if (new_ptrs_size < paca_ptrs_size)
325 memblock_phys_free(__pa(paca_ptrs) + new_ptrs_size,
326 paca_ptrs_size - new_ptrs_size);
327
328 paca_nr_cpu_ids = nr_cpu_ids;
329 paca_ptrs_size = new_ptrs_size;
330
331 #ifdef CONFIG_PPC_BOOK3S_64
332 if (early_radix_enabled()) {
333 /* Ugly fixup, see new_slb_shadow() */
334 memblock_phys_free(__pa(paca_ptrs[boot_cpuid]->slb_shadow_ptr),
335 sizeof(struct slb_shadow));
336 paca_ptrs[boot_cpuid]->slb_shadow_ptr = NULL;
337 }
338 #endif
339
340 printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
341 paca_ptrs_size + paca_struct_size, nr_cpu_ids);
342 }
343
copy_mm_to_paca(struct mm_struct * mm)344 void copy_mm_to_paca(struct mm_struct *mm)
345 {
346 #ifdef CONFIG_PPC_BOOK3S
347 mm_context_t *context = &mm->context;
348
349 #ifdef CONFIG_PPC_MM_SLICES
350 VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
351 memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
352 LOW_SLICE_ARRAY_SZ);
353 memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
354 TASK_SLICE_ARRAY_SZ(context));
355 #else /* CONFIG_PPC_MM_SLICES */
356 get_paca()->mm_ctx_user_psize = context->user_psize;
357 get_paca()->mm_ctx_sllp = context->sllp;
358 #endif
359 #else /* !CONFIG_PPC_BOOK3S */
360 return;
361 #endif
362 }
363