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
26static 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
59static 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/arch/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 */
108static 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
121static 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_64S_HASH_MMU
142/*
143 * 3 persistent SLBs are allocated here.  The buffer will be zero
144 * initially, hence will all be invaild until we actually write them.
145 *
146 * If you make the number of persistent SLB entries dynamic, please also
147 * update PR KVM to flush and restore them accordingly.
148 */
149static struct slb_shadow * __init new_slb_shadow(int cpu, unsigned long limit)
150{
151	struct slb_shadow *s;
152
153	if (cpu != boot_cpuid) {
154		/*
155		 * Boot CPU comes here before early_radix_enabled
156		 * is parsed (e.g., for disable_radix). So allocate
157		 * always and this will be fixed up in free_unused_pacas.
158		 */
159		if (early_radix_enabled())
160			return NULL;
161	}
162
163	s = alloc_paca_data(sizeof(*s), L1_CACHE_BYTES, limit, cpu);
164
165	s->persistent = cpu_to_be32(SLB_NUM_BOLTED);
166	s->buffer_length = cpu_to_be32(sizeof(*s));
167
168	return s;
169}
170#endif /* CONFIG_PPC_64S_HASH_MMU */
171
172/* The Paca is an array with one entry per processor.  Each contains an
173 * lppaca, which contains the information shared between the
174 * hypervisor and Linux.
175 * On systems with hardware multi-threading, there are two threads
176 * per processor.  The Paca array must contain an entry for each thread.
177 * The VPD Areas will give a max logical processors = 2 * max physical
178 * processors.  The processor VPD array needs one entry per physical
179 * processor (not thread).
180 */
181struct paca_struct **paca_ptrs __read_mostly;
182EXPORT_SYMBOL(paca_ptrs);
183
184void __init initialise_paca(struct paca_struct *new_paca, int cpu)
185{
186#ifdef CONFIG_PPC_PSERIES
187	new_paca->lppaca_ptr = NULL;
188#endif
189#ifdef CONFIG_PPC_BOOK3E_64
190	new_paca->kernel_pgd = swapper_pg_dir;
191#endif
192	new_paca->lock_token = 0x8000;
193	new_paca->paca_index = cpu;
194#ifndef CONFIG_PPC_KERNEL_PCREL
195	new_paca->kernel_toc = kernel_toc_addr();
196#endif
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_64S_HASH_MMU
205	new_paca->slb_shadow_ptr = NULL;
206#endif
207
208#ifdef CONFIG_PPC_BOOK3E_64
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 */
215void setup_paca(struct paca_struct *new_paca)
216{
217	/* Setup r13 */
218	local_paca = new_paca;
219
220#ifdef CONFIG_PPC_BOOK3E_64
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
239static int __initdata paca_nr_cpu_ids;
240static int __initdata paca_ptrs_size;
241static int __initdata paca_struct_size;
242
243void __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
256void __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_64S_HASH_MMU
282	paca->slb_shadow_ptr = new_slb_shadow(cpu, limit);
283#endif
284	paca_struct_size += sizeof(struct paca_struct);
285}
286
287void __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_phys_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_64S_HASH_MMU
300	if (early_radix_enabled()) {
301		/* Ugly fixup, see new_slb_shadow() */
302		memblock_phys_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
312#ifdef CONFIG_PPC_64S_HASH_MMU
313void copy_mm_to_paca(struct mm_struct *mm)
314{
315	mm_context_t *context = &mm->context;
316
317	VM_BUG_ON(!mm_ctx_slb_addr_limit(context));
318	memcpy(&get_paca()->mm_ctx_low_slices_psize, mm_ctx_low_slices(context),
319	       LOW_SLICE_ARRAY_SZ);
320	memcpy(&get_paca()->mm_ctx_high_slices_psize, mm_ctx_high_slices(context),
321	       TASK_SLICE_ARRAY_SZ(context));
322}
323#endif /* CONFIG_PPC_64S_HASH_MMU */
324