1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2008-2011 Freescale Semiconductor, Inc. All rights reserved.
4 *
5 * Author: Yu Liu, <yu.liu@freescale.com>
6 *
7 * Description:
8 * This file is derived from arch/powerpc/kvm/44x.c,
9 * by Hollis Blanchard <hollisb@us.ibm.com>.
10 */
11
12#include <linux/kvm_host.h>
13#include <linux/slab.h>
14#include <linux/err.h>
15#include <linux/export.h>
16#include <linux/module.h>
17#include <linux/miscdevice.h>
18
19#include <asm/reg.h>
20#include <asm/cputable.h>
21#include <asm/kvm_ppc.h>
22
23#include "../mm/mmu_decl.h"
24#include "booke.h"
25#include "e500.h"
26
27struct id {
28	unsigned long val;
29	struct id **pentry;
30};
31
32#define NUM_TIDS 256
33
34/*
35 * This table provide mappings from:
36 * (guestAS,guestTID,guestPR) --> ID of physical cpu
37 * guestAS	[0..1]
38 * guestTID	[0..255]
39 * guestPR	[0..1]
40 * ID		[1..255]
41 * Each vcpu keeps one vcpu_id_table.
42 */
43struct vcpu_id_table {
44	struct id id[2][NUM_TIDS][2];
45};
46
47/*
48 * This table provide reversed mappings of vcpu_id_table:
49 * ID --> address of vcpu_id_table item.
50 * Each physical core has one pcpu_id_table.
51 */
52struct pcpu_id_table {
53	struct id *entry[NUM_TIDS];
54};
55
56static DEFINE_PER_CPU(struct pcpu_id_table, pcpu_sids);
57
58/* This variable keeps last used shadow ID on local core.
59 * The valid range of shadow ID is [1..255] */
60static DEFINE_PER_CPU(unsigned long, pcpu_last_used_sid);
61
62/*
63 * Allocate a free shadow id and setup a valid sid mapping in given entry.
64 * A mapping is only valid when vcpu_id_table and pcpu_id_table are match.
65 *
66 * The caller must have preemption disabled, and keep it that way until
67 * it has finished with the returned shadow id (either written into the
68 * TLB or arch.shadow_pid, or discarded).
69 */
70static inline int local_sid_setup_one(struct id *entry)
71{
72	unsigned long sid;
73	int ret = -1;
74
75	sid = __this_cpu_inc_return(pcpu_last_used_sid);
76	if (sid < NUM_TIDS) {
77		__this_cpu_write(pcpu_sids.entry[sid], entry);
78		entry->val = sid;
79		entry->pentry = this_cpu_ptr(&pcpu_sids.entry[sid]);
80		ret = sid;
81	}
82
83	/*
84	 * If sid == NUM_TIDS, we've run out of sids.  We return -1, and
85	 * the caller will invalidate everything and start over.
86	 *
87	 * sid > NUM_TIDS indicates a race, which we disable preemption to
88	 * avoid.
89	 */
90	WARN_ON(sid > NUM_TIDS);
91
92	return ret;
93}
94
95/*
96 * Check if given entry contain a valid shadow id mapping.
97 * An ID mapping is considered valid only if
98 * both vcpu and pcpu know this mapping.
99 *
100 * The caller must have preemption disabled, and keep it that way until
101 * it has finished with the returned shadow id (either written into the
102 * TLB or arch.shadow_pid, or discarded).
103 */
104static inline int local_sid_lookup(struct id *entry)
105{
106	if (entry && entry->val != 0 &&
107	    __this_cpu_read(pcpu_sids.entry[entry->val]) == entry &&
108	    entry->pentry == this_cpu_ptr(&pcpu_sids.entry[entry->val]))
109		return entry->val;
110	return -1;
111}
112
113/* Invalidate all id mappings on local core -- call with preempt disabled */
114static inline void local_sid_destroy_all(void)
115{
116	__this_cpu_write(pcpu_last_used_sid, 0);
117	memset(this_cpu_ptr(&pcpu_sids), 0, sizeof(pcpu_sids));
118}
119
120static void *kvmppc_e500_id_table_alloc(struct kvmppc_vcpu_e500 *vcpu_e500)
121{
122	vcpu_e500->idt = kzalloc(sizeof(struct vcpu_id_table), GFP_KERNEL);
123	return vcpu_e500->idt;
124}
125
126static void kvmppc_e500_id_table_free(struct kvmppc_vcpu_e500 *vcpu_e500)
127{
128	kfree(vcpu_e500->idt);
129	vcpu_e500->idt = NULL;
130}
131
132/* Map guest pid to shadow.
133 * We use PID to keep shadow of current guest non-zero PID,
134 * and use PID1 to keep shadow of guest zero PID.
135 * So that guest tlbe with TID=0 can be accessed at any time */
136static void kvmppc_e500_recalc_shadow_pid(struct kvmppc_vcpu_e500 *vcpu_e500)
137{
138	preempt_disable();
139	vcpu_e500->vcpu.arch.shadow_pid = kvmppc_e500_get_sid(vcpu_e500,
140			get_cur_as(&vcpu_e500->vcpu),
141			get_cur_pid(&vcpu_e500->vcpu),
142			get_cur_pr(&vcpu_e500->vcpu), 1);
143	vcpu_e500->vcpu.arch.shadow_pid1 = kvmppc_e500_get_sid(vcpu_e500,
144			get_cur_as(&vcpu_e500->vcpu), 0,
145			get_cur_pr(&vcpu_e500->vcpu), 1);
146	preempt_enable();
147}
148
149/* Invalidate all mappings on vcpu */
150static void kvmppc_e500_id_table_reset_all(struct kvmppc_vcpu_e500 *vcpu_e500)
151{
152	memset(vcpu_e500->idt, 0, sizeof(struct vcpu_id_table));
153
154	/* Update shadow pid when mappings are changed */
155	kvmppc_e500_recalc_shadow_pid(vcpu_e500);
156}
157
158/* Invalidate one ID mapping on vcpu */
159static inline void kvmppc_e500_id_table_reset_one(
160			       struct kvmppc_vcpu_e500 *vcpu_e500,
161			       int as, int pid, int pr)
162{
163	struct vcpu_id_table *idt = vcpu_e500->idt;
164
165	BUG_ON(as >= 2);
166	BUG_ON(pid >= NUM_TIDS);
167	BUG_ON(pr >= 2);
168
169	idt->id[as][pid][pr].val = 0;
170	idt->id[as][pid][pr].pentry = NULL;
171
172	/* Update shadow pid when mappings are changed */
173	kvmppc_e500_recalc_shadow_pid(vcpu_e500);
174}
175
176/*
177 * Map guest (vcpu,AS,ID,PR) to physical core shadow id.
178 * This function first lookup if a valid mapping exists,
179 * if not, then creates a new one.
180 *
181 * The caller must have preemption disabled, and keep it that way until
182 * it has finished with the returned shadow id (either written into the
183 * TLB or arch.shadow_pid, or discarded).
184 */
185unsigned int kvmppc_e500_get_sid(struct kvmppc_vcpu_e500 *vcpu_e500,
186				 unsigned int as, unsigned int gid,
187				 unsigned int pr, int avoid_recursion)
188{
189	struct vcpu_id_table *idt = vcpu_e500->idt;
190	int sid;
191
192	BUG_ON(as >= 2);
193	BUG_ON(gid >= NUM_TIDS);
194	BUG_ON(pr >= 2);
195
196	sid = local_sid_lookup(&idt->id[as][gid][pr]);
197
198	while (sid <= 0) {
199		/* No mapping yet */
200		sid = local_sid_setup_one(&idt->id[as][gid][pr]);
201		if (sid <= 0) {
202			_tlbil_all();
203			local_sid_destroy_all();
204		}
205
206		/* Update shadow pid when mappings are changed */
207		if (!avoid_recursion)
208			kvmppc_e500_recalc_shadow_pid(vcpu_e500);
209	}
210
211	return sid;
212}
213
214unsigned int kvmppc_e500_get_tlb_stid(struct kvm_vcpu *vcpu,
215				      struct kvm_book3e_206_tlb_entry *gtlbe)
216{
217	return kvmppc_e500_get_sid(to_e500(vcpu), get_tlb_ts(gtlbe),
218				   get_tlb_tid(gtlbe), get_cur_pr(vcpu), 0);
219}
220
221void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 pid)
222{
223	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
224
225	if (vcpu->arch.pid != pid) {
226		vcpu_e500->pid[0] = vcpu->arch.pid = pid;
227		kvmppc_e500_recalc_shadow_pid(vcpu_e500);
228	}
229}
230
231/* gtlbe must not be mapped by more than one host tlbe */
232void kvmppc_e500_tlbil_one(struct kvmppc_vcpu_e500 *vcpu_e500,
233                           struct kvm_book3e_206_tlb_entry *gtlbe)
234{
235	struct vcpu_id_table *idt = vcpu_e500->idt;
236	unsigned int pr, tid, ts;
237	int pid;
238	u32 val, eaddr;
239	unsigned long flags;
240
241	ts = get_tlb_ts(gtlbe);
242	tid = get_tlb_tid(gtlbe);
243
244	preempt_disable();
245
246	/* One guest ID may be mapped to two shadow IDs */
247	for (pr = 0; pr < 2; pr++) {
248		/*
249		 * The shadow PID can have a valid mapping on at most one
250		 * host CPU.  In the common case, it will be valid on this
251		 * CPU, in which case we do a local invalidation of the
252		 * specific address.
253		 *
254		 * If the shadow PID is not valid on the current host CPU,
255		 * we invalidate the entire shadow PID.
256		 */
257		pid = local_sid_lookup(&idt->id[ts][tid][pr]);
258		if (pid <= 0) {
259			kvmppc_e500_id_table_reset_one(vcpu_e500, ts, tid, pr);
260			continue;
261		}
262
263		/*
264		 * The guest is invalidating a 4K entry which is in a PID
265		 * that has a valid shadow mapping on this host CPU.  We
266		 * search host TLB to invalidate it's shadow TLB entry,
267		 * similar to __tlbil_va except that we need to look in AS1.
268		 */
269		val = (pid << MAS6_SPID_SHIFT) | MAS6_SAS;
270		eaddr = get_tlb_eaddr(gtlbe);
271
272		local_irq_save(flags);
273
274		mtspr(SPRN_MAS6, val);
275		asm volatile("tlbsx 0, %[eaddr]" : : [eaddr] "r" (eaddr));
276		val = mfspr(SPRN_MAS1);
277		if (val & MAS1_VALID) {
278			mtspr(SPRN_MAS1, val & ~MAS1_VALID);
279			asm volatile("tlbwe");
280		}
281
282		local_irq_restore(flags);
283	}
284
285	preempt_enable();
286}
287
288void kvmppc_e500_tlbil_all(struct kvmppc_vcpu_e500 *vcpu_e500)
289{
290	kvmppc_e500_id_table_reset_all(vcpu_e500);
291}
292
293void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr)
294{
295	/* Recalc shadow pid since MSR changes */
296	kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
297}
298
299static void kvmppc_core_vcpu_load_e500(struct kvm_vcpu *vcpu, int cpu)
300{
301	kvmppc_booke_vcpu_load(vcpu, cpu);
302
303	/* Shadow PID may be expired on local core */
304	kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
305}
306
307static void kvmppc_core_vcpu_put_e500(struct kvm_vcpu *vcpu)
308{
309#ifdef CONFIG_SPE
310	if (vcpu->arch.shadow_msr & MSR_SPE)
311		kvmppc_vcpu_disable_spe(vcpu);
312#endif
313
314	kvmppc_booke_vcpu_put(vcpu);
315}
316
317static int kvmppc_e500_check_processor_compat(void)
318{
319	int r;
320
321	if (strcmp(cur_cpu_spec->cpu_name, "e500v2") == 0)
322		r = 0;
323	else
324		r = -ENOTSUPP;
325
326	return r;
327}
328
329static void kvmppc_e500_tlb_setup(struct kvmppc_vcpu_e500 *vcpu_e500)
330{
331	struct kvm_book3e_206_tlb_entry *tlbe;
332
333	/* Insert large initial mapping for guest. */
334	tlbe = get_entry(vcpu_e500, 1, 0);
335	tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_256M);
336	tlbe->mas2 = 0;
337	tlbe->mas7_3 = E500_TLB_SUPER_PERM_MASK;
338
339	/* 4K map for serial output. Used by kernel wrapper. */
340	tlbe = get_entry(vcpu_e500, 1, 1);
341	tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_4K);
342	tlbe->mas2 = (0xe0004500 & 0xFFFFF000) | MAS2_I | MAS2_G;
343	tlbe->mas7_3 = (0xe0004500 & 0xFFFFF000) | E500_TLB_SUPER_PERM_MASK;
344}
345
346int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
347{
348	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
349
350	kvmppc_e500_tlb_setup(vcpu_e500);
351
352	/* Registers init */
353	vcpu->arch.pvr = mfspr(SPRN_PVR);
354	vcpu_e500->svr = mfspr(SPRN_SVR);
355
356	vcpu->arch.cpu_type = KVM_CPU_E500V2;
357
358	return 0;
359}
360
361static int kvmppc_core_get_sregs_e500(struct kvm_vcpu *vcpu,
362				      struct kvm_sregs *sregs)
363{
364	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
365
366	sregs->u.e.features |= KVM_SREGS_E_ARCH206_MMU | KVM_SREGS_E_SPE |
367	                       KVM_SREGS_E_PM;
368	sregs->u.e.impl_id = KVM_SREGS_E_IMPL_FSL;
369
370	sregs->u.e.impl.fsl.features = 0;
371	sregs->u.e.impl.fsl.svr = vcpu_e500->svr;
372	sregs->u.e.impl.fsl.hid0 = vcpu_e500->hid0;
373	sregs->u.e.impl.fsl.mcar = vcpu_e500->mcar;
374
375	sregs->u.e.ivor_high[0] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL];
376	sregs->u.e.ivor_high[1] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA];
377	sregs->u.e.ivor_high[2] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND];
378	sregs->u.e.ivor_high[3] =
379		vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR];
380
381	kvmppc_get_sregs_ivor(vcpu, sregs);
382	kvmppc_get_sregs_e500_tlb(vcpu, sregs);
383	return 0;
384}
385
386static int kvmppc_core_set_sregs_e500(struct kvm_vcpu *vcpu,
387				      struct kvm_sregs *sregs)
388{
389	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
390	int ret;
391
392	if (sregs->u.e.impl_id == KVM_SREGS_E_IMPL_FSL) {
393		vcpu_e500->svr = sregs->u.e.impl.fsl.svr;
394		vcpu_e500->hid0 = sregs->u.e.impl.fsl.hid0;
395		vcpu_e500->mcar = sregs->u.e.impl.fsl.mcar;
396	}
397
398	ret = kvmppc_set_sregs_e500_tlb(vcpu, sregs);
399	if (ret < 0)
400		return ret;
401
402	if (!(sregs->u.e.features & KVM_SREGS_E_IVOR))
403		return 0;
404
405	if (sregs->u.e.features & KVM_SREGS_E_SPE) {
406		vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL] =
407			sregs->u.e.ivor_high[0];
408		vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA] =
409			sregs->u.e.ivor_high[1];
410		vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND] =
411			sregs->u.e.ivor_high[2];
412	}
413
414	if (sregs->u.e.features & KVM_SREGS_E_PM) {
415		vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR] =
416			sregs->u.e.ivor_high[3];
417	}
418
419	return kvmppc_set_sregs_ivor(vcpu, sregs);
420}
421
422static int kvmppc_get_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
423				   union kvmppc_one_reg *val)
424{
425	int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
426	return r;
427}
428
429static int kvmppc_set_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
430				   union kvmppc_one_reg *val)
431{
432	int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
433	return r;
434}
435
436static int kvmppc_core_vcpu_create_e500(struct kvm_vcpu *vcpu)
437{
438	struct kvmppc_vcpu_e500 *vcpu_e500;
439	int err;
440
441	BUILD_BUG_ON(offsetof(struct kvmppc_vcpu_e500, vcpu) != 0);
442	vcpu_e500 = to_e500(vcpu);
443
444	if (kvmppc_e500_id_table_alloc(vcpu_e500) == NULL)
445		return -ENOMEM;
446
447	err = kvmppc_e500_tlb_init(vcpu_e500);
448	if (err)
449		goto uninit_id;
450
451	vcpu->arch.shared = (void*)__get_free_page(GFP_KERNEL|__GFP_ZERO);
452	if (!vcpu->arch.shared) {
453		err = -ENOMEM;
454		goto uninit_tlb;
455	}
456
457	return 0;
458
459uninit_tlb:
460	kvmppc_e500_tlb_uninit(vcpu_e500);
461uninit_id:
462	kvmppc_e500_id_table_free(vcpu_e500);
463	return err;
464}
465
466static void kvmppc_core_vcpu_free_e500(struct kvm_vcpu *vcpu)
467{
468	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
469
470	free_page((unsigned long)vcpu->arch.shared);
471	kvmppc_e500_tlb_uninit(vcpu_e500);
472	kvmppc_e500_id_table_free(vcpu_e500);
473}
474
475static int kvmppc_core_init_vm_e500(struct kvm *kvm)
476{
477	return 0;
478}
479
480static void kvmppc_core_destroy_vm_e500(struct kvm *kvm)
481{
482}
483
484static struct kvmppc_ops kvm_ops_e500 = {
485	.get_sregs = kvmppc_core_get_sregs_e500,
486	.set_sregs = kvmppc_core_set_sregs_e500,
487	.get_one_reg = kvmppc_get_one_reg_e500,
488	.set_one_reg = kvmppc_set_one_reg_e500,
489	.vcpu_load   = kvmppc_core_vcpu_load_e500,
490	.vcpu_put    = kvmppc_core_vcpu_put_e500,
491	.vcpu_create = kvmppc_core_vcpu_create_e500,
492	.vcpu_free   = kvmppc_core_vcpu_free_e500,
493	.init_vm = kvmppc_core_init_vm_e500,
494	.destroy_vm = kvmppc_core_destroy_vm_e500,
495	.emulate_op = kvmppc_core_emulate_op_e500,
496	.emulate_mtspr = kvmppc_core_emulate_mtspr_e500,
497	.emulate_mfspr = kvmppc_core_emulate_mfspr_e500,
498	.create_vcpu_debugfs = kvmppc_create_vcpu_debugfs_e500,
499};
500
501static int __init kvmppc_e500_init(void)
502{
503	int r, i;
504	unsigned long ivor[3];
505	/* Process remaining handlers above the generic first 16 */
506	unsigned long *handler = &kvmppc_booke_handler_addr[16];
507	unsigned long handler_len;
508	unsigned long max_ivor = 0;
509
510	r = kvmppc_e500_check_processor_compat();
511	if (r)
512		goto err_out;
513
514	r = kvmppc_booke_init();
515	if (r)
516		goto err_out;
517
518	/* copy extra E500 exception handlers */
519	ivor[0] = mfspr(SPRN_IVOR32);
520	ivor[1] = mfspr(SPRN_IVOR33);
521	ivor[2] = mfspr(SPRN_IVOR34);
522	for (i = 0; i < 3; i++) {
523		if (ivor[i] > ivor[max_ivor])
524			max_ivor = i;
525
526		handler_len = handler[i + 1] - handler[i];
527		memcpy((void *)kvmppc_booke_handlers + ivor[i],
528		       (void *)handler[i], handler_len);
529	}
530	handler_len = handler[max_ivor + 1] - handler[max_ivor];
531	flush_icache_range(kvmppc_booke_handlers, kvmppc_booke_handlers +
532			   ivor[max_ivor] + handler_len);
533
534	r = kvm_init(sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
535	if (r)
536		goto err_out;
537	kvm_ops_e500.owner = THIS_MODULE;
538	kvmppc_pr_ops = &kvm_ops_e500;
539
540err_out:
541	return r;
542}
543
544static void __exit kvmppc_e500_exit(void)
545{
546	kvmppc_pr_ops = NULL;
547	kvmppc_booke_exit();
548}
549
550module_init(kvmppc_e500_init);
551module_exit(kvmppc_e500_exit);
552MODULE_ALIAS_MISCDEV(KVM_MINOR);
553MODULE_ALIAS("devname:kvm");
554