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