xref: /openbmc/linux/arch/arm64/kvm/sys_regs.c (revision 6189f1b0)
1 /*
2  * Copyright (C) 2012,2013 - ARM Ltd
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * Derived from arch/arm/kvm/coproc.c:
6  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
7  * Authors: Rusty Russell <rusty@rustcorp.com.au>
8  *          Christoffer Dall <c.dall@virtualopensystems.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License, version 2, as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include <linux/kvm_host.h>
24 #include <linux/mm.h>
25 #include <linux/uaccess.h>
26 
27 #include <asm/cacheflush.h>
28 #include <asm/cputype.h>
29 #include <asm/debug-monitors.h>
30 #include <asm/esr.h>
31 #include <asm/kvm_arm.h>
32 #include <asm/kvm_coproc.h>
33 #include <asm/kvm_emulate.h>
34 #include <asm/kvm_host.h>
35 #include <asm/kvm_mmu.h>
36 
37 #include <trace/events/kvm.h>
38 
39 #include "sys_regs.h"
40 
41 /*
42  * All of this file is extremly similar to the ARM coproc.c, but the
43  * types are different. My gut feeling is that it should be pretty
44  * easy to merge, but that would be an ABI breakage -- again. VFP
45  * would also need to be abstracted.
46  *
47  * For AArch32, we only take care of what is being trapped. Anything
48  * that has to do with init and userspace access has to go via the
49  * 64bit interface.
50  */
51 
52 /* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
53 static u32 cache_levels;
54 
55 /* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
56 #define CSSELR_MAX 12
57 
58 /* Which cache CCSIDR represents depends on CSSELR value. */
59 static u32 get_ccsidr(u32 csselr)
60 {
61 	u32 ccsidr;
62 
63 	/* Make sure noone else changes CSSELR during this! */
64 	local_irq_disable();
65 	/* Put value into CSSELR */
66 	asm volatile("msr csselr_el1, %x0" : : "r" (csselr));
67 	isb();
68 	/* Read result out of CCSIDR */
69 	asm volatile("mrs %0, ccsidr_el1" : "=r" (ccsidr));
70 	local_irq_enable();
71 
72 	return ccsidr;
73 }
74 
75 /*
76  * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
77  */
78 static bool access_dcsw(struct kvm_vcpu *vcpu,
79 			const struct sys_reg_params *p,
80 			const struct sys_reg_desc *r)
81 {
82 	if (!p->is_write)
83 		return read_from_write_only(vcpu, p);
84 
85 	kvm_set_way_flush(vcpu);
86 	return true;
87 }
88 
89 /*
90  * Generic accessor for VM registers. Only called as long as HCR_TVM
91  * is set. If the guest enables the MMU, we stop trapping the VM
92  * sys_regs and leave it in complete control of the caches.
93  */
94 static bool access_vm_reg(struct kvm_vcpu *vcpu,
95 			  const struct sys_reg_params *p,
96 			  const struct sys_reg_desc *r)
97 {
98 	unsigned long val;
99 	bool was_enabled = vcpu_has_cache_enabled(vcpu);
100 
101 	BUG_ON(!p->is_write);
102 
103 	val = *vcpu_reg(vcpu, p->Rt);
104 	if (!p->is_aarch32) {
105 		vcpu_sys_reg(vcpu, r->reg) = val;
106 	} else {
107 		if (!p->is_32bit)
108 			vcpu_cp15_64_high(vcpu, r->reg) = val >> 32;
109 		vcpu_cp15_64_low(vcpu, r->reg) = val & 0xffffffffUL;
110 	}
111 
112 	kvm_toggle_cache(vcpu, was_enabled);
113 	return true;
114 }
115 
116 /*
117  * Trap handler for the GICv3 SGI generation system register.
118  * Forward the request to the VGIC emulation.
119  * The cp15_64 code makes sure this automatically works
120  * for both AArch64 and AArch32 accesses.
121  */
122 static bool access_gic_sgi(struct kvm_vcpu *vcpu,
123 			   const struct sys_reg_params *p,
124 			   const struct sys_reg_desc *r)
125 {
126 	u64 val;
127 
128 	if (!p->is_write)
129 		return read_from_write_only(vcpu, p);
130 
131 	val = *vcpu_reg(vcpu, p->Rt);
132 	vgic_v3_dispatch_sgi(vcpu, val);
133 
134 	return true;
135 }
136 
137 static bool trap_raz_wi(struct kvm_vcpu *vcpu,
138 			const struct sys_reg_params *p,
139 			const struct sys_reg_desc *r)
140 {
141 	if (p->is_write)
142 		return ignore_write(vcpu, p);
143 	else
144 		return read_zero(vcpu, p);
145 }
146 
147 static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
148 			   const struct sys_reg_params *p,
149 			   const struct sys_reg_desc *r)
150 {
151 	if (p->is_write) {
152 		return ignore_write(vcpu, p);
153 	} else {
154 		*vcpu_reg(vcpu, p->Rt) = (1 << 3);
155 		return true;
156 	}
157 }
158 
159 static bool trap_dbgauthstatus_el1(struct kvm_vcpu *vcpu,
160 				   const struct sys_reg_params *p,
161 				   const struct sys_reg_desc *r)
162 {
163 	if (p->is_write) {
164 		return ignore_write(vcpu, p);
165 	} else {
166 		u32 val;
167 		asm volatile("mrs %0, dbgauthstatus_el1" : "=r" (val));
168 		*vcpu_reg(vcpu, p->Rt) = val;
169 		return true;
170 	}
171 }
172 
173 /*
174  * We want to avoid world-switching all the DBG registers all the
175  * time:
176  *
177  * - If we've touched any debug register, it is likely that we're
178  *   going to touch more of them. It then makes sense to disable the
179  *   traps and start doing the save/restore dance
180  * - If debug is active (DBG_MDSCR_KDE or DBG_MDSCR_MDE set), it is
181  *   then mandatory to save/restore the registers, as the guest
182  *   depends on them.
183  *
184  * For this, we use a DIRTY bit, indicating the guest has modified the
185  * debug registers, used as follow:
186  *
187  * On guest entry:
188  * - If the dirty bit is set (because we're coming back from trapping),
189  *   disable the traps, save host registers, restore guest registers.
190  * - If debug is actively in use (DBG_MDSCR_KDE or DBG_MDSCR_MDE set),
191  *   set the dirty bit, disable the traps, save host registers,
192  *   restore guest registers.
193  * - Otherwise, enable the traps
194  *
195  * On guest exit:
196  * - If the dirty bit is set, save guest registers, restore host
197  *   registers and clear the dirty bit. This ensure that the host can
198  *   now use the debug registers.
199  */
200 static bool trap_debug_regs(struct kvm_vcpu *vcpu,
201 			    const struct sys_reg_params *p,
202 			    const struct sys_reg_desc *r)
203 {
204 	if (p->is_write) {
205 		vcpu_sys_reg(vcpu, r->reg) = *vcpu_reg(vcpu, p->Rt);
206 		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
207 	} else {
208 		*vcpu_reg(vcpu, p->Rt) = vcpu_sys_reg(vcpu, r->reg);
209 	}
210 
211 	return true;
212 }
213 
214 static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
215 {
216 	u64 amair;
217 
218 	asm volatile("mrs %0, amair_el1\n" : "=r" (amair));
219 	vcpu_sys_reg(vcpu, AMAIR_EL1) = amair;
220 }
221 
222 static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
223 {
224 	u64 mpidr;
225 
226 	/*
227 	 * Map the vcpu_id into the first three affinity level fields of
228 	 * the MPIDR. We limit the number of VCPUs in level 0 due to a
229 	 * limitation to 16 CPUs in that level in the ICC_SGIxR registers
230 	 * of the GICv3 to be able to address each CPU directly when
231 	 * sending IPIs.
232 	 */
233 	mpidr = (vcpu->vcpu_id & 0x0f) << MPIDR_LEVEL_SHIFT(0);
234 	mpidr |= ((vcpu->vcpu_id >> 4) & 0xff) << MPIDR_LEVEL_SHIFT(1);
235 	mpidr |= ((vcpu->vcpu_id >> 12) & 0xff) << MPIDR_LEVEL_SHIFT(2);
236 	vcpu_sys_reg(vcpu, MPIDR_EL1) = (1ULL << 31) | mpidr;
237 }
238 
239 /* Silly macro to expand the DBG{BCR,BVR,WVR,WCR}n_EL1 registers in one go */
240 #define DBG_BCR_BVR_WCR_WVR_EL1(n)					\
241 	/* DBGBVRn_EL1 */						\
242 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b100),	\
243 	  trap_debug_regs, reset_val, (DBGBVR0_EL1 + (n)), 0 },		\
244 	/* DBGBCRn_EL1 */						\
245 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b101),	\
246 	  trap_debug_regs, reset_val, (DBGBCR0_EL1 + (n)), 0 },		\
247 	/* DBGWVRn_EL1 */						\
248 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b110),	\
249 	  trap_debug_regs, reset_val, (DBGWVR0_EL1 + (n)), 0 },		\
250 	/* DBGWCRn_EL1 */						\
251 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111),	\
252 	  trap_debug_regs, reset_val, (DBGWCR0_EL1 + (n)), 0 }
253 
254 /*
255  * Architected system registers.
256  * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
257  *
258  * We could trap ID_DFR0 and tell the guest we don't support performance
259  * monitoring.  Unfortunately the patch to make the kernel check ID_DFR0 was
260  * NAKed, so it will read the PMCR anyway.
261  *
262  * Therefore we tell the guest we have 0 counters.  Unfortunately, we
263  * must always support PMCCNTR (the cycle counter): we just RAZ/WI for
264  * all PM registers, which doesn't crash the guest kernel at least.
265  *
266  * Debug handling: We do trap most, if not all debug related system
267  * registers. The implementation is good enough to ensure that a guest
268  * can use these with minimal performance degradation. The drawback is
269  * that we don't implement any of the external debug, none of the
270  * OSlock protocol. This should be revisited if we ever encounter a
271  * more demanding guest...
272  */
273 static const struct sys_reg_desc sys_reg_descs[] = {
274 	/* DC ISW */
275 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b0110), Op2(0b010),
276 	  access_dcsw },
277 	/* DC CSW */
278 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1010), Op2(0b010),
279 	  access_dcsw },
280 	/* DC CISW */
281 	{ Op0(0b01), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b010),
282 	  access_dcsw },
283 
284 	DBG_BCR_BVR_WCR_WVR_EL1(0),
285 	DBG_BCR_BVR_WCR_WVR_EL1(1),
286 	/* MDCCINT_EL1 */
287 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b000),
288 	  trap_debug_regs, reset_val, MDCCINT_EL1, 0 },
289 	/* MDSCR_EL1 */
290 	{ Op0(0b10), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b010),
291 	  trap_debug_regs, reset_val, MDSCR_EL1, 0 },
292 	DBG_BCR_BVR_WCR_WVR_EL1(2),
293 	DBG_BCR_BVR_WCR_WVR_EL1(3),
294 	DBG_BCR_BVR_WCR_WVR_EL1(4),
295 	DBG_BCR_BVR_WCR_WVR_EL1(5),
296 	DBG_BCR_BVR_WCR_WVR_EL1(6),
297 	DBG_BCR_BVR_WCR_WVR_EL1(7),
298 	DBG_BCR_BVR_WCR_WVR_EL1(8),
299 	DBG_BCR_BVR_WCR_WVR_EL1(9),
300 	DBG_BCR_BVR_WCR_WVR_EL1(10),
301 	DBG_BCR_BVR_WCR_WVR_EL1(11),
302 	DBG_BCR_BVR_WCR_WVR_EL1(12),
303 	DBG_BCR_BVR_WCR_WVR_EL1(13),
304 	DBG_BCR_BVR_WCR_WVR_EL1(14),
305 	DBG_BCR_BVR_WCR_WVR_EL1(15),
306 
307 	/* MDRAR_EL1 */
308 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
309 	  trap_raz_wi },
310 	/* OSLAR_EL1 */
311 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b100),
312 	  trap_raz_wi },
313 	/* OSLSR_EL1 */
314 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0001), Op2(0b100),
315 	  trap_oslsr_el1 },
316 	/* OSDLR_EL1 */
317 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0011), Op2(0b100),
318 	  trap_raz_wi },
319 	/* DBGPRCR_EL1 */
320 	{ Op0(0b10), Op1(0b000), CRn(0b0001), CRm(0b0100), Op2(0b100),
321 	  trap_raz_wi },
322 	/* DBGCLAIMSET_EL1 */
323 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1000), Op2(0b110),
324 	  trap_raz_wi },
325 	/* DBGCLAIMCLR_EL1 */
326 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1001), Op2(0b110),
327 	  trap_raz_wi },
328 	/* DBGAUTHSTATUS_EL1 */
329 	{ Op0(0b10), Op1(0b000), CRn(0b0111), CRm(0b1110), Op2(0b110),
330 	  trap_dbgauthstatus_el1 },
331 
332 	/* TEECR32_EL1 */
333 	{ Op0(0b10), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
334 	  NULL, reset_val, TEECR32_EL1, 0 },
335 	/* TEEHBR32_EL1 */
336 	{ Op0(0b10), Op1(0b010), CRn(0b0001), CRm(0b0000), Op2(0b000),
337 	  NULL, reset_val, TEEHBR32_EL1, 0 },
338 
339 	/* MDCCSR_EL1 */
340 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0001), Op2(0b000),
341 	  trap_raz_wi },
342 	/* DBGDTR_EL0 */
343 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0100), Op2(0b000),
344 	  trap_raz_wi },
345 	/* DBGDTR[TR]X_EL0 */
346 	{ Op0(0b10), Op1(0b011), CRn(0b0000), CRm(0b0101), Op2(0b000),
347 	  trap_raz_wi },
348 
349 	/* DBGVCR32_EL2 */
350 	{ Op0(0b10), Op1(0b100), CRn(0b0000), CRm(0b0111), Op2(0b000),
351 	  NULL, reset_val, DBGVCR32_EL2, 0 },
352 
353 	/* MPIDR_EL1 */
354 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b101),
355 	  NULL, reset_mpidr, MPIDR_EL1 },
356 	/* SCTLR_EL1 */
357 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
358 	  access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 },
359 	/* CPACR_EL1 */
360 	{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b010),
361 	  NULL, reset_val, CPACR_EL1, 0 },
362 	/* TTBR0_EL1 */
363 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b000),
364 	  access_vm_reg, reset_unknown, TTBR0_EL1 },
365 	/* TTBR1_EL1 */
366 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b001),
367 	  access_vm_reg, reset_unknown, TTBR1_EL1 },
368 	/* TCR_EL1 */
369 	{ Op0(0b11), Op1(0b000), CRn(0b0010), CRm(0b0000), Op2(0b010),
370 	  access_vm_reg, reset_val, TCR_EL1, 0 },
371 
372 	/* AFSR0_EL1 */
373 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b000),
374 	  access_vm_reg, reset_unknown, AFSR0_EL1 },
375 	/* AFSR1_EL1 */
376 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0001), Op2(0b001),
377 	  access_vm_reg, reset_unknown, AFSR1_EL1 },
378 	/* ESR_EL1 */
379 	{ Op0(0b11), Op1(0b000), CRn(0b0101), CRm(0b0010), Op2(0b000),
380 	  access_vm_reg, reset_unknown, ESR_EL1 },
381 	/* FAR_EL1 */
382 	{ Op0(0b11), Op1(0b000), CRn(0b0110), CRm(0b0000), Op2(0b000),
383 	  access_vm_reg, reset_unknown, FAR_EL1 },
384 	/* PAR_EL1 */
385 	{ Op0(0b11), Op1(0b000), CRn(0b0111), CRm(0b0100), Op2(0b000),
386 	  NULL, reset_unknown, PAR_EL1 },
387 
388 	/* PMINTENSET_EL1 */
389 	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b001),
390 	  trap_raz_wi },
391 	/* PMINTENCLR_EL1 */
392 	{ Op0(0b11), Op1(0b000), CRn(0b1001), CRm(0b1110), Op2(0b010),
393 	  trap_raz_wi },
394 
395 	/* MAIR_EL1 */
396 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0010), Op2(0b000),
397 	  access_vm_reg, reset_unknown, MAIR_EL1 },
398 	/* AMAIR_EL1 */
399 	{ Op0(0b11), Op1(0b000), CRn(0b1010), CRm(0b0011), Op2(0b000),
400 	  access_vm_reg, reset_amair_el1, AMAIR_EL1 },
401 
402 	/* VBAR_EL1 */
403 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b0000), Op2(0b000),
404 	  NULL, reset_val, VBAR_EL1, 0 },
405 
406 	/* ICC_SGI1R_EL1 */
407 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b1011), Op2(0b101),
408 	  access_gic_sgi },
409 	/* ICC_SRE_EL1 */
410 	{ Op0(0b11), Op1(0b000), CRn(0b1100), CRm(0b1100), Op2(0b101),
411 	  trap_raz_wi },
412 
413 	/* CONTEXTIDR_EL1 */
414 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b001),
415 	  access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
416 	/* TPIDR_EL1 */
417 	{ Op0(0b11), Op1(0b000), CRn(0b1101), CRm(0b0000), Op2(0b100),
418 	  NULL, reset_unknown, TPIDR_EL1 },
419 
420 	/* CNTKCTL_EL1 */
421 	{ Op0(0b11), Op1(0b000), CRn(0b1110), CRm(0b0001), Op2(0b000),
422 	  NULL, reset_val, CNTKCTL_EL1, 0},
423 
424 	/* CSSELR_EL1 */
425 	{ Op0(0b11), Op1(0b010), CRn(0b0000), CRm(0b0000), Op2(0b000),
426 	  NULL, reset_unknown, CSSELR_EL1 },
427 
428 	/* PMCR_EL0 */
429 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b000),
430 	  trap_raz_wi },
431 	/* PMCNTENSET_EL0 */
432 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b001),
433 	  trap_raz_wi },
434 	/* PMCNTENCLR_EL0 */
435 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b010),
436 	  trap_raz_wi },
437 	/* PMOVSCLR_EL0 */
438 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b011),
439 	  trap_raz_wi },
440 	/* PMSWINC_EL0 */
441 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b100),
442 	  trap_raz_wi },
443 	/* PMSELR_EL0 */
444 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b101),
445 	  trap_raz_wi },
446 	/* PMCEID0_EL0 */
447 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b110),
448 	  trap_raz_wi },
449 	/* PMCEID1_EL0 */
450 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1100), Op2(0b111),
451 	  trap_raz_wi },
452 	/* PMCCNTR_EL0 */
453 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b000),
454 	  trap_raz_wi },
455 	/* PMXEVTYPER_EL0 */
456 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b001),
457 	  trap_raz_wi },
458 	/* PMXEVCNTR_EL0 */
459 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1101), Op2(0b010),
460 	  trap_raz_wi },
461 	/* PMUSERENR_EL0 */
462 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b000),
463 	  trap_raz_wi },
464 	/* PMOVSSET_EL0 */
465 	{ Op0(0b11), Op1(0b011), CRn(0b1001), CRm(0b1110), Op2(0b011),
466 	  trap_raz_wi },
467 
468 	/* TPIDR_EL0 */
469 	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b010),
470 	  NULL, reset_unknown, TPIDR_EL0 },
471 	/* TPIDRRO_EL0 */
472 	{ Op0(0b11), Op1(0b011), CRn(0b1101), CRm(0b0000), Op2(0b011),
473 	  NULL, reset_unknown, TPIDRRO_EL0 },
474 
475 	/* DACR32_EL2 */
476 	{ Op0(0b11), Op1(0b100), CRn(0b0011), CRm(0b0000), Op2(0b000),
477 	  NULL, reset_unknown, DACR32_EL2 },
478 	/* IFSR32_EL2 */
479 	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0000), Op2(0b001),
480 	  NULL, reset_unknown, IFSR32_EL2 },
481 	/* FPEXC32_EL2 */
482 	{ Op0(0b11), Op1(0b100), CRn(0b0101), CRm(0b0011), Op2(0b000),
483 	  NULL, reset_val, FPEXC32_EL2, 0x70 },
484 };
485 
486 static bool trap_dbgidr(struct kvm_vcpu *vcpu,
487 			const struct sys_reg_params *p,
488 			const struct sys_reg_desc *r)
489 {
490 	if (p->is_write) {
491 		return ignore_write(vcpu, p);
492 	} else {
493 		u64 dfr = read_cpuid(ID_AA64DFR0_EL1);
494 		u64 pfr = read_cpuid(ID_AA64PFR0_EL1);
495 		u32 el3 = !!((pfr >> 12) & 0xf);
496 
497 		*vcpu_reg(vcpu, p->Rt) = ((((dfr >> 20) & 0xf) << 28) |
498 					  (((dfr >> 12) & 0xf) << 24) |
499 					  (((dfr >> 28) & 0xf) << 20) |
500 					  (6 << 16) | (el3 << 14) | (el3 << 12));
501 		return true;
502 	}
503 }
504 
505 static bool trap_debug32(struct kvm_vcpu *vcpu,
506 			 const struct sys_reg_params *p,
507 			 const struct sys_reg_desc *r)
508 {
509 	if (p->is_write) {
510 		vcpu_cp14(vcpu, r->reg) = *vcpu_reg(vcpu, p->Rt);
511 		vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
512 	} else {
513 		*vcpu_reg(vcpu, p->Rt) = vcpu_cp14(vcpu, r->reg);
514 	}
515 
516 	return true;
517 }
518 
519 #define DBG_BCR_BVR_WCR_WVR(n)					\
520 	/* DBGBVRn */						\
521 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_debug32,	\
522 	  NULL, (cp14_DBGBVR0 + (n) * 2) },			\
523 	/* DBGBCRn */						\
524 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_debug32,	\
525 	  NULL, (cp14_DBGBCR0 + (n) * 2) },			\
526 	/* DBGWVRn */						\
527 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_debug32,	\
528 	  NULL, (cp14_DBGWVR0 + (n) * 2) },			\
529 	/* DBGWCRn */						\
530 	{ Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_debug32,	\
531 	  NULL, (cp14_DBGWCR0 + (n) * 2) }
532 
533 #define DBGBXVR(n)						\
534 	{ Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_debug32,	\
535 	  NULL, cp14_DBGBXVR0 + n * 2 }
536 
537 /*
538  * Trapped cp14 registers. We generally ignore most of the external
539  * debug, on the principle that they don't really make sense to a
540  * guest. Revisit this one day, whould this principle change.
541  */
542 static const struct sys_reg_desc cp14_regs[] = {
543 	/* DBGIDR */
544 	{ Op1( 0), CRn( 0), CRm( 0), Op2( 0), trap_dbgidr },
545 	/* DBGDTRRXext */
546 	{ Op1( 0), CRn( 0), CRm( 0), Op2( 2), trap_raz_wi },
547 
548 	DBG_BCR_BVR_WCR_WVR(0),
549 	/* DBGDSCRint */
550 	{ Op1( 0), CRn( 0), CRm( 1), Op2( 0), trap_raz_wi },
551 	DBG_BCR_BVR_WCR_WVR(1),
552 	/* DBGDCCINT */
553 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), trap_debug32 },
554 	/* DBGDSCRext */
555 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 2), trap_debug32 },
556 	DBG_BCR_BVR_WCR_WVR(2),
557 	/* DBGDTR[RT]Xint */
558 	{ Op1( 0), CRn( 0), CRm( 3), Op2( 0), trap_raz_wi },
559 	/* DBGDTR[RT]Xext */
560 	{ Op1( 0), CRn( 0), CRm( 3), Op2( 2), trap_raz_wi },
561 	DBG_BCR_BVR_WCR_WVR(3),
562 	DBG_BCR_BVR_WCR_WVR(4),
563 	DBG_BCR_BVR_WCR_WVR(5),
564 	/* DBGWFAR */
565 	{ Op1( 0), CRn( 0), CRm( 6), Op2( 0), trap_raz_wi },
566 	/* DBGOSECCR */
567 	{ Op1( 0), CRn( 0), CRm( 6), Op2( 2), trap_raz_wi },
568 	DBG_BCR_BVR_WCR_WVR(6),
569 	/* DBGVCR */
570 	{ Op1( 0), CRn( 0), CRm( 7), Op2( 0), trap_debug32 },
571 	DBG_BCR_BVR_WCR_WVR(7),
572 	DBG_BCR_BVR_WCR_WVR(8),
573 	DBG_BCR_BVR_WCR_WVR(9),
574 	DBG_BCR_BVR_WCR_WVR(10),
575 	DBG_BCR_BVR_WCR_WVR(11),
576 	DBG_BCR_BVR_WCR_WVR(12),
577 	DBG_BCR_BVR_WCR_WVR(13),
578 	DBG_BCR_BVR_WCR_WVR(14),
579 	DBG_BCR_BVR_WCR_WVR(15),
580 
581 	/* DBGDRAR (32bit) */
582 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), trap_raz_wi },
583 
584 	DBGBXVR(0),
585 	/* DBGOSLAR */
586 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 4), trap_raz_wi },
587 	DBGBXVR(1),
588 	/* DBGOSLSR */
589 	{ Op1( 0), CRn( 1), CRm( 1), Op2( 4), trap_oslsr_el1 },
590 	DBGBXVR(2),
591 	DBGBXVR(3),
592 	/* DBGOSDLR */
593 	{ Op1( 0), CRn( 1), CRm( 3), Op2( 4), trap_raz_wi },
594 	DBGBXVR(4),
595 	/* DBGPRCR */
596 	{ Op1( 0), CRn( 1), CRm( 4), Op2( 4), trap_raz_wi },
597 	DBGBXVR(5),
598 	DBGBXVR(6),
599 	DBGBXVR(7),
600 	DBGBXVR(8),
601 	DBGBXVR(9),
602 	DBGBXVR(10),
603 	DBGBXVR(11),
604 	DBGBXVR(12),
605 	DBGBXVR(13),
606 	DBGBXVR(14),
607 	DBGBXVR(15),
608 
609 	/* DBGDSAR (32bit) */
610 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), trap_raz_wi },
611 
612 	/* DBGDEVID2 */
613 	{ Op1( 0), CRn( 7), CRm( 0), Op2( 7), trap_raz_wi },
614 	/* DBGDEVID1 */
615 	{ Op1( 0), CRn( 7), CRm( 1), Op2( 7), trap_raz_wi },
616 	/* DBGDEVID */
617 	{ Op1( 0), CRn( 7), CRm( 2), Op2( 7), trap_raz_wi },
618 	/* DBGCLAIMSET */
619 	{ Op1( 0), CRn( 7), CRm( 8), Op2( 6), trap_raz_wi },
620 	/* DBGCLAIMCLR */
621 	{ Op1( 0), CRn( 7), CRm( 9), Op2( 6), trap_raz_wi },
622 	/* DBGAUTHSTATUS */
623 	{ Op1( 0), CRn( 7), CRm(14), Op2( 6), trap_dbgauthstatus_el1 },
624 };
625 
626 /* Trapped cp14 64bit registers */
627 static const struct sys_reg_desc cp14_64_regs[] = {
628 	/* DBGDRAR (64bit) */
629 	{ Op1( 0), CRm( 1), .access = trap_raz_wi },
630 
631 	/* DBGDSAR (64bit) */
632 	{ Op1( 0), CRm( 2), .access = trap_raz_wi },
633 };
634 
635 /*
636  * Trapped cp15 registers. TTBR0/TTBR1 get a double encoding,
637  * depending on the way they are accessed (as a 32bit or a 64bit
638  * register).
639  */
640 static const struct sys_reg_desc cp15_regs[] = {
641 	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
642 
643 	{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_vm_reg, NULL, c1_SCTLR },
644 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
645 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
646 	{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
647 	{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
648 	{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
649 	{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },
650 	{ Op1( 0), CRn( 5), CRm( 1), Op2( 0), access_vm_reg, NULL, c5_ADFSR },
651 	{ Op1( 0), CRn( 5), CRm( 1), Op2( 1), access_vm_reg, NULL, c5_AIFSR },
652 	{ Op1( 0), CRn( 6), CRm( 0), Op2( 0), access_vm_reg, NULL, c6_DFAR },
653 	{ Op1( 0), CRn( 6), CRm( 0), Op2( 2), access_vm_reg, NULL, c6_IFAR },
654 
655 	/*
656 	 * DC{C,I,CI}SW operations:
657 	 */
658 	{ Op1( 0), CRn( 7), CRm( 6), Op2( 2), access_dcsw },
659 	{ Op1( 0), CRn( 7), CRm(10), Op2( 2), access_dcsw },
660 	{ Op1( 0), CRn( 7), CRm(14), Op2( 2), access_dcsw },
661 
662 	/* PMU */
663 	{ Op1( 0), CRn( 9), CRm(12), Op2( 0), trap_raz_wi },
664 	{ Op1( 0), CRn( 9), CRm(12), Op2( 1), trap_raz_wi },
665 	{ Op1( 0), CRn( 9), CRm(12), Op2( 2), trap_raz_wi },
666 	{ Op1( 0), CRn( 9), CRm(12), Op2( 3), trap_raz_wi },
667 	{ Op1( 0), CRn( 9), CRm(12), Op2( 5), trap_raz_wi },
668 	{ Op1( 0), CRn( 9), CRm(12), Op2( 6), trap_raz_wi },
669 	{ Op1( 0), CRn( 9), CRm(12), Op2( 7), trap_raz_wi },
670 	{ Op1( 0), CRn( 9), CRm(13), Op2( 0), trap_raz_wi },
671 	{ Op1( 0), CRn( 9), CRm(13), Op2( 1), trap_raz_wi },
672 	{ Op1( 0), CRn( 9), CRm(13), Op2( 2), trap_raz_wi },
673 	{ Op1( 0), CRn( 9), CRm(14), Op2( 0), trap_raz_wi },
674 	{ Op1( 0), CRn( 9), CRm(14), Op2( 1), trap_raz_wi },
675 	{ Op1( 0), CRn( 9), CRm(14), Op2( 2), trap_raz_wi },
676 
677 	{ Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, c10_PRRR },
678 	{ Op1( 0), CRn(10), CRm( 2), Op2( 1), access_vm_reg, NULL, c10_NMRR },
679 	{ Op1( 0), CRn(10), CRm( 3), Op2( 0), access_vm_reg, NULL, c10_AMAIR0 },
680 	{ Op1( 0), CRn(10), CRm( 3), Op2( 1), access_vm_reg, NULL, c10_AMAIR1 },
681 
682 	/* ICC_SRE */
683 	{ Op1( 0), CRn(12), CRm(12), Op2( 5), trap_raz_wi },
684 
685 	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
686 };
687 
688 static const struct sys_reg_desc cp15_64_regs[] = {
689 	{ Op1( 0), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
690 	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
691 	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
692 };
693 
694 /* Target specific emulation tables */
695 static struct kvm_sys_reg_target_table *target_tables[KVM_ARM_NUM_TARGETS];
696 
697 void kvm_register_target_sys_reg_table(unsigned int target,
698 				       struct kvm_sys_reg_target_table *table)
699 {
700 	target_tables[target] = table;
701 }
702 
703 /* Get specific register table for this target. */
704 static const struct sys_reg_desc *get_target_table(unsigned target,
705 						   bool mode_is_64,
706 						   size_t *num)
707 {
708 	struct kvm_sys_reg_target_table *table;
709 
710 	table = target_tables[target];
711 	if (mode_is_64) {
712 		*num = table->table64.num;
713 		return table->table64.table;
714 	} else {
715 		*num = table->table32.num;
716 		return table->table32.table;
717 	}
718 }
719 
720 static const struct sys_reg_desc *find_reg(const struct sys_reg_params *params,
721 					 const struct sys_reg_desc table[],
722 					 unsigned int num)
723 {
724 	unsigned int i;
725 
726 	for (i = 0; i < num; i++) {
727 		const struct sys_reg_desc *r = &table[i];
728 
729 		if (params->Op0 != r->Op0)
730 			continue;
731 		if (params->Op1 != r->Op1)
732 			continue;
733 		if (params->CRn != r->CRn)
734 			continue;
735 		if (params->CRm != r->CRm)
736 			continue;
737 		if (params->Op2 != r->Op2)
738 			continue;
739 
740 		return r;
741 	}
742 	return NULL;
743 }
744 
745 int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
746 {
747 	kvm_inject_undefined(vcpu);
748 	return 1;
749 }
750 
751 /*
752  * emulate_cp --  tries to match a sys_reg access in a handling table, and
753  *                call the corresponding trap handler.
754  *
755  * @params: pointer to the descriptor of the access
756  * @table: array of trap descriptors
757  * @num: size of the trap descriptor array
758  *
759  * Return 0 if the access has been handled, and -1 if not.
760  */
761 static int emulate_cp(struct kvm_vcpu *vcpu,
762 		      const struct sys_reg_params *params,
763 		      const struct sys_reg_desc *table,
764 		      size_t num)
765 {
766 	const struct sys_reg_desc *r;
767 
768 	if (!table)
769 		return -1;	/* Not handled */
770 
771 	r = find_reg(params, table, num);
772 
773 	if (r) {
774 		/*
775 		 * Not having an accessor means that we have
776 		 * configured a trap that we don't know how to
777 		 * handle. This certainly qualifies as a gross bug
778 		 * that should be fixed right away.
779 		 */
780 		BUG_ON(!r->access);
781 
782 		if (likely(r->access(vcpu, params, r))) {
783 			/* Skip instruction, since it was emulated */
784 			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
785 		}
786 
787 		/* Handled */
788 		return 0;
789 	}
790 
791 	/* Not handled */
792 	return -1;
793 }
794 
795 static void unhandled_cp_access(struct kvm_vcpu *vcpu,
796 				struct sys_reg_params *params)
797 {
798 	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
799 	int cp;
800 
801 	switch(hsr_ec) {
802 	case ESR_ELx_EC_CP15_32:
803 	case ESR_ELx_EC_CP15_64:
804 		cp = 15;
805 		break;
806 	case ESR_ELx_EC_CP14_MR:
807 	case ESR_ELx_EC_CP14_64:
808 		cp = 14;
809 		break;
810 	default:
811 		WARN_ON((cp = -1));
812 	}
813 
814 	kvm_err("Unsupported guest CP%d access at: %08lx\n",
815 		cp, *vcpu_pc(vcpu));
816 	print_sys_reg_instr(params);
817 	kvm_inject_undefined(vcpu);
818 }
819 
820 /**
821  * kvm_handle_cp_64 -- handles a mrrc/mcrr trap on a guest CP15 access
822  * @vcpu: The VCPU pointer
823  * @run:  The kvm_run struct
824  */
825 static int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
826 			    const struct sys_reg_desc *global,
827 			    size_t nr_global,
828 			    const struct sys_reg_desc *target_specific,
829 			    size_t nr_specific)
830 {
831 	struct sys_reg_params params;
832 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
833 	int Rt2 = (hsr >> 10) & 0xf;
834 
835 	params.is_aarch32 = true;
836 	params.is_32bit = false;
837 	params.CRm = (hsr >> 1) & 0xf;
838 	params.Rt = (hsr >> 5) & 0xf;
839 	params.is_write = ((hsr & 1) == 0);
840 
841 	params.Op0 = 0;
842 	params.Op1 = (hsr >> 16) & 0xf;
843 	params.Op2 = 0;
844 	params.CRn = 0;
845 
846 	/*
847 	 * Massive hack here. Store Rt2 in the top 32bits so we only
848 	 * have one register to deal with. As we use the same trap
849 	 * backends between AArch32 and AArch64, we get away with it.
850 	 */
851 	if (params.is_write) {
852 		u64 val = *vcpu_reg(vcpu, params.Rt);
853 		val &= 0xffffffff;
854 		val |= *vcpu_reg(vcpu, Rt2) << 32;
855 		*vcpu_reg(vcpu, params.Rt) = val;
856 	}
857 
858 	if (!emulate_cp(vcpu, &params, target_specific, nr_specific))
859 		goto out;
860 	if (!emulate_cp(vcpu, &params, global, nr_global))
861 		goto out;
862 
863 	unhandled_cp_access(vcpu, &params);
864 
865 out:
866 	/* Do the opposite hack for the read side */
867 	if (!params.is_write) {
868 		u64 val = *vcpu_reg(vcpu, params.Rt);
869 		val >>= 32;
870 		*vcpu_reg(vcpu, Rt2) = val;
871 	}
872 
873 	return 1;
874 }
875 
876 /**
877  * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
878  * @vcpu: The VCPU pointer
879  * @run:  The kvm_run struct
880  */
881 static int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
882 			    const struct sys_reg_desc *global,
883 			    size_t nr_global,
884 			    const struct sys_reg_desc *target_specific,
885 			    size_t nr_specific)
886 {
887 	struct sys_reg_params params;
888 	u32 hsr = kvm_vcpu_get_hsr(vcpu);
889 
890 	params.is_aarch32 = true;
891 	params.is_32bit = true;
892 	params.CRm = (hsr >> 1) & 0xf;
893 	params.Rt  = (hsr >> 5) & 0xf;
894 	params.is_write = ((hsr & 1) == 0);
895 	params.CRn = (hsr >> 10) & 0xf;
896 	params.Op0 = 0;
897 	params.Op1 = (hsr >> 14) & 0x7;
898 	params.Op2 = (hsr >> 17) & 0x7;
899 
900 	if (!emulate_cp(vcpu, &params, target_specific, nr_specific))
901 		return 1;
902 	if (!emulate_cp(vcpu, &params, global, nr_global))
903 		return 1;
904 
905 	unhandled_cp_access(vcpu, &params);
906 	return 1;
907 }
908 
909 int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
910 {
911 	const struct sys_reg_desc *target_specific;
912 	size_t num;
913 
914 	target_specific = get_target_table(vcpu->arch.target, false, &num);
915 	return kvm_handle_cp_64(vcpu,
916 				cp15_64_regs, ARRAY_SIZE(cp15_64_regs),
917 				target_specific, num);
918 }
919 
920 int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
921 {
922 	const struct sys_reg_desc *target_specific;
923 	size_t num;
924 
925 	target_specific = get_target_table(vcpu->arch.target, false, &num);
926 	return kvm_handle_cp_32(vcpu,
927 				cp15_regs, ARRAY_SIZE(cp15_regs),
928 				target_specific, num);
929 }
930 
931 int kvm_handle_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
932 {
933 	return kvm_handle_cp_64(vcpu,
934 				cp14_64_regs, ARRAY_SIZE(cp14_64_regs),
935 				NULL, 0);
936 }
937 
938 int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
939 {
940 	return kvm_handle_cp_32(vcpu,
941 				cp14_regs, ARRAY_SIZE(cp14_regs),
942 				NULL, 0);
943 }
944 
945 static int emulate_sys_reg(struct kvm_vcpu *vcpu,
946 			   const struct sys_reg_params *params)
947 {
948 	size_t num;
949 	const struct sys_reg_desc *table, *r;
950 
951 	table = get_target_table(vcpu->arch.target, true, &num);
952 
953 	/* Search target-specific then generic table. */
954 	r = find_reg(params, table, num);
955 	if (!r)
956 		r = find_reg(params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
957 
958 	if (likely(r)) {
959 		/*
960 		 * Not having an accessor means that we have
961 		 * configured a trap that we don't know how to
962 		 * handle. This certainly qualifies as a gross bug
963 		 * that should be fixed right away.
964 		 */
965 		BUG_ON(!r->access);
966 
967 		if (likely(r->access(vcpu, params, r))) {
968 			/* Skip instruction, since it was emulated */
969 			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
970 			return 1;
971 		}
972 		/* If access function fails, it should complain. */
973 	} else {
974 		kvm_err("Unsupported guest sys_reg access at: %lx\n",
975 			*vcpu_pc(vcpu));
976 		print_sys_reg_instr(params);
977 	}
978 	kvm_inject_undefined(vcpu);
979 	return 1;
980 }
981 
982 static void reset_sys_reg_descs(struct kvm_vcpu *vcpu,
983 			      const struct sys_reg_desc *table, size_t num)
984 {
985 	unsigned long i;
986 
987 	for (i = 0; i < num; i++)
988 		if (table[i].reset)
989 			table[i].reset(vcpu, &table[i]);
990 }
991 
992 /**
993  * kvm_handle_sys_reg -- handles a mrs/msr trap on a guest sys_reg access
994  * @vcpu: The VCPU pointer
995  * @run:  The kvm_run struct
996  */
997 int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run)
998 {
999 	struct sys_reg_params params;
1000 	unsigned long esr = kvm_vcpu_get_hsr(vcpu);
1001 
1002 	params.is_aarch32 = false;
1003 	params.is_32bit = false;
1004 	params.Op0 = (esr >> 20) & 3;
1005 	params.Op1 = (esr >> 14) & 0x7;
1006 	params.CRn = (esr >> 10) & 0xf;
1007 	params.CRm = (esr >> 1) & 0xf;
1008 	params.Op2 = (esr >> 17) & 0x7;
1009 	params.Rt = (esr >> 5) & 0x1f;
1010 	params.is_write = !(esr & 1);
1011 
1012 	return emulate_sys_reg(vcpu, &params);
1013 }
1014 
1015 /******************************************************************************
1016  * Userspace API
1017  *****************************************************************************/
1018 
1019 static bool index_to_params(u64 id, struct sys_reg_params *params)
1020 {
1021 	switch (id & KVM_REG_SIZE_MASK) {
1022 	case KVM_REG_SIZE_U64:
1023 		/* Any unused index bits means it's not valid. */
1024 		if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
1025 			      | KVM_REG_ARM_COPROC_MASK
1026 			      | KVM_REG_ARM64_SYSREG_OP0_MASK
1027 			      | KVM_REG_ARM64_SYSREG_OP1_MASK
1028 			      | KVM_REG_ARM64_SYSREG_CRN_MASK
1029 			      | KVM_REG_ARM64_SYSREG_CRM_MASK
1030 			      | KVM_REG_ARM64_SYSREG_OP2_MASK))
1031 			return false;
1032 		params->Op0 = ((id & KVM_REG_ARM64_SYSREG_OP0_MASK)
1033 			       >> KVM_REG_ARM64_SYSREG_OP0_SHIFT);
1034 		params->Op1 = ((id & KVM_REG_ARM64_SYSREG_OP1_MASK)
1035 			       >> KVM_REG_ARM64_SYSREG_OP1_SHIFT);
1036 		params->CRn = ((id & KVM_REG_ARM64_SYSREG_CRN_MASK)
1037 			       >> KVM_REG_ARM64_SYSREG_CRN_SHIFT);
1038 		params->CRm = ((id & KVM_REG_ARM64_SYSREG_CRM_MASK)
1039 			       >> KVM_REG_ARM64_SYSREG_CRM_SHIFT);
1040 		params->Op2 = ((id & KVM_REG_ARM64_SYSREG_OP2_MASK)
1041 			       >> KVM_REG_ARM64_SYSREG_OP2_SHIFT);
1042 		return true;
1043 	default:
1044 		return false;
1045 	}
1046 }
1047 
1048 /* Decode an index value, and find the sys_reg_desc entry. */
1049 static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu,
1050 						    u64 id)
1051 {
1052 	size_t num;
1053 	const struct sys_reg_desc *table, *r;
1054 	struct sys_reg_params params;
1055 
1056 	/* We only do sys_reg for now. */
1057 	if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG)
1058 		return NULL;
1059 
1060 	if (!index_to_params(id, &params))
1061 		return NULL;
1062 
1063 	table = get_target_table(vcpu->arch.target, true, &num);
1064 	r = find_reg(&params, table, num);
1065 	if (!r)
1066 		r = find_reg(&params, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
1067 
1068 	/* Not saved in the sys_reg array? */
1069 	if (r && !r->reg)
1070 		r = NULL;
1071 
1072 	return r;
1073 }
1074 
1075 /*
1076  * These are the invariant sys_reg registers: we let the guest see the
1077  * host versions of these, so they're part of the guest state.
1078  *
1079  * A future CPU may provide a mechanism to present different values to
1080  * the guest, or a future kvm may trap them.
1081  */
1082 
1083 #define FUNCTION_INVARIANT(reg)						\
1084 	static void get_##reg(struct kvm_vcpu *v,			\
1085 			      const struct sys_reg_desc *r)		\
1086 	{								\
1087 		u64 val;						\
1088 									\
1089 		asm volatile("mrs %0, " __stringify(reg) "\n"		\
1090 			     : "=r" (val));				\
1091 		((struct sys_reg_desc *)r)->val = val;			\
1092 	}
1093 
1094 FUNCTION_INVARIANT(midr_el1)
1095 FUNCTION_INVARIANT(ctr_el0)
1096 FUNCTION_INVARIANT(revidr_el1)
1097 FUNCTION_INVARIANT(id_pfr0_el1)
1098 FUNCTION_INVARIANT(id_pfr1_el1)
1099 FUNCTION_INVARIANT(id_dfr0_el1)
1100 FUNCTION_INVARIANT(id_afr0_el1)
1101 FUNCTION_INVARIANT(id_mmfr0_el1)
1102 FUNCTION_INVARIANT(id_mmfr1_el1)
1103 FUNCTION_INVARIANT(id_mmfr2_el1)
1104 FUNCTION_INVARIANT(id_mmfr3_el1)
1105 FUNCTION_INVARIANT(id_isar0_el1)
1106 FUNCTION_INVARIANT(id_isar1_el1)
1107 FUNCTION_INVARIANT(id_isar2_el1)
1108 FUNCTION_INVARIANT(id_isar3_el1)
1109 FUNCTION_INVARIANT(id_isar4_el1)
1110 FUNCTION_INVARIANT(id_isar5_el1)
1111 FUNCTION_INVARIANT(clidr_el1)
1112 FUNCTION_INVARIANT(aidr_el1)
1113 
1114 /* ->val is filled in by kvm_sys_reg_table_init() */
1115 static struct sys_reg_desc invariant_sys_regs[] = {
1116 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b000),
1117 	  NULL, get_midr_el1 },
1118 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0000), Op2(0b110),
1119 	  NULL, get_revidr_el1 },
1120 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b000),
1121 	  NULL, get_id_pfr0_el1 },
1122 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b001),
1123 	  NULL, get_id_pfr1_el1 },
1124 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b010),
1125 	  NULL, get_id_dfr0_el1 },
1126 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b011),
1127 	  NULL, get_id_afr0_el1 },
1128 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b100),
1129 	  NULL, get_id_mmfr0_el1 },
1130 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b101),
1131 	  NULL, get_id_mmfr1_el1 },
1132 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b110),
1133 	  NULL, get_id_mmfr2_el1 },
1134 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0001), Op2(0b111),
1135 	  NULL, get_id_mmfr3_el1 },
1136 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b000),
1137 	  NULL, get_id_isar0_el1 },
1138 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b001),
1139 	  NULL, get_id_isar1_el1 },
1140 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b010),
1141 	  NULL, get_id_isar2_el1 },
1142 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b011),
1143 	  NULL, get_id_isar3_el1 },
1144 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b100),
1145 	  NULL, get_id_isar4_el1 },
1146 	{ Op0(0b11), Op1(0b000), CRn(0b0000), CRm(0b0010), Op2(0b101),
1147 	  NULL, get_id_isar5_el1 },
1148 	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b001),
1149 	  NULL, get_clidr_el1 },
1150 	{ Op0(0b11), Op1(0b001), CRn(0b0000), CRm(0b0000), Op2(0b111),
1151 	  NULL, get_aidr_el1 },
1152 	{ Op0(0b11), Op1(0b011), CRn(0b0000), CRm(0b0000), Op2(0b001),
1153 	  NULL, get_ctr_el0 },
1154 };
1155 
1156 static int reg_from_user(u64 *val, const void __user *uaddr, u64 id)
1157 {
1158 	if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
1159 		return -EFAULT;
1160 	return 0;
1161 }
1162 
1163 static int reg_to_user(void __user *uaddr, const u64 *val, u64 id)
1164 {
1165 	if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
1166 		return -EFAULT;
1167 	return 0;
1168 }
1169 
1170 static int get_invariant_sys_reg(u64 id, void __user *uaddr)
1171 {
1172 	struct sys_reg_params params;
1173 	const struct sys_reg_desc *r;
1174 
1175 	if (!index_to_params(id, &params))
1176 		return -ENOENT;
1177 
1178 	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
1179 	if (!r)
1180 		return -ENOENT;
1181 
1182 	return reg_to_user(uaddr, &r->val, id);
1183 }
1184 
1185 static int set_invariant_sys_reg(u64 id, void __user *uaddr)
1186 {
1187 	struct sys_reg_params params;
1188 	const struct sys_reg_desc *r;
1189 	int err;
1190 	u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */
1191 
1192 	if (!index_to_params(id, &params))
1193 		return -ENOENT;
1194 	r = find_reg(&params, invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs));
1195 	if (!r)
1196 		return -ENOENT;
1197 
1198 	err = reg_from_user(&val, uaddr, id);
1199 	if (err)
1200 		return err;
1201 
1202 	/* This is what we mean by invariant: you can't change it. */
1203 	if (r->val != val)
1204 		return -EINVAL;
1205 
1206 	return 0;
1207 }
1208 
1209 static bool is_valid_cache(u32 val)
1210 {
1211 	u32 level, ctype;
1212 
1213 	if (val >= CSSELR_MAX)
1214 		return false;
1215 
1216 	/* Bottom bit is Instruction or Data bit.  Next 3 bits are level. */
1217 	level = (val >> 1);
1218 	ctype = (cache_levels >> (level * 3)) & 7;
1219 
1220 	switch (ctype) {
1221 	case 0: /* No cache */
1222 		return false;
1223 	case 1: /* Instruction cache only */
1224 		return (val & 1);
1225 	case 2: /* Data cache only */
1226 	case 4: /* Unified cache */
1227 		return !(val & 1);
1228 	case 3: /* Separate instruction and data caches */
1229 		return true;
1230 	default: /* Reserved: we can't know instruction or data. */
1231 		return false;
1232 	}
1233 }
1234 
1235 static int demux_c15_get(u64 id, void __user *uaddr)
1236 {
1237 	u32 val;
1238 	u32 __user *uval = uaddr;
1239 
1240 	/* Fail if we have unknown bits set. */
1241 	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
1242 		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
1243 		return -ENOENT;
1244 
1245 	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
1246 	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
1247 		if (KVM_REG_SIZE(id) != 4)
1248 			return -ENOENT;
1249 		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
1250 			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
1251 		if (!is_valid_cache(val))
1252 			return -ENOENT;
1253 
1254 		return put_user(get_ccsidr(val), uval);
1255 	default:
1256 		return -ENOENT;
1257 	}
1258 }
1259 
1260 static int demux_c15_set(u64 id, void __user *uaddr)
1261 {
1262 	u32 val, newval;
1263 	u32 __user *uval = uaddr;
1264 
1265 	/* Fail if we have unknown bits set. */
1266 	if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
1267 		   | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
1268 		return -ENOENT;
1269 
1270 	switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
1271 	case KVM_REG_ARM_DEMUX_ID_CCSIDR:
1272 		if (KVM_REG_SIZE(id) != 4)
1273 			return -ENOENT;
1274 		val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
1275 			>> KVM_REG_ARM_DEMUX_VAL_SHIFT;
1276 		if (!is_valid_cache(val))
1277 			return -ENOENT;
1278 
1279 		if (get_user(newval, uval))
1280 			return -EFAULT;
1281 
1282 		/* This is also invariant: you can't change it. */
1283 		if (newval != get_ccsidr(val))
1284 			return -EINVAL;
1285 		return 0;
1286 	default:
1287 		return -ENOENT;
1288 	}
1289 }
1290 
1291 int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1292 {
1293 	const struct sys_reg_desc *r;
1294 	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
1295 
1296 	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1297 		return demux_c15_get(reg->id, uaddr);
1298 
1299 	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
1300 		return -ENOENT;
1301 
1302 	r = index_to_sys_reg_desc(vcpu, reg->id);
1303 	if (!r)
1304 		return get_invariant_sys_reg(reg->id, uaddr);
1305 
1306 	return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id);
1307 }
1308 
1309 int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
1310 {
1311 	const struct sys_reg_desc *r;
1312 	void __user *uaddr = (void __user *)(unsigned long)reg->addr;
1313 
1314 	if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
1315 		return demux_c15_set(reg->id, uaddr);
1316 
1317 	if (KVM_REG_SIZE(reg->id) != sizeof(__u64))
1318 		return -ENOENT;
1319 
1320 	r = index_to_sys_reg_desc(vcpu, reg->id);
1321 	if (!r)
1322 		return set_invariant_sys_reg(reg->id, uaddr);
1323 
1324 	return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id);
1325 }
1326 
1327 static unsigned int num_demux_regs(void)
1328 {
1329 	unsigned int i, count = 0;
1330 
1331 	for (i = 0; i < CSSELR_MAX; i++)
1332 		if (is_valid_cache(i))
1333 			count++;
1334 
1335 	return count;
1336 }
1337 
1338 static int write_demux_regids(u64 __user *uindices)
1339 {
1340 	u64 val = KVM_REG_ARM64 | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
1341 	unsigned int i;
1342 
1343 	val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
1344 	for (i = 0; i < CSSELR_MAX; i++) {
1345 		if (!is_valid_cache(i))
1346 			continue;
1347 		if (put_user(val | i, uindices))
1348 			return -EFAULT;
1349 		uindices++;
1350 	}
1351 	return 0;
1352 }
1353 
1354 static u64 sys_reg_to_index(const struct sys_reg_desc *reg)
1355 {
1356 	return (KVM_REG_ARM64 | KVM_REG_SIZE_U64 |
1357 		KVM_REG_ARM64_SYSREG |
1358 		(reg->Op0 << KVM_REG_ARM64_SYSREG_OP0_SHIFT) |
1359 		(reg->Op1 << KVM_REG_ARM64_SYSREG_OP1_SHIFT) |
1360 		(reg->CRn << KVM_REG_ARM64_SYSREG_CRN_SHIFT) |
1361 		(reg->CRm << KVM_REG_ARM64_SYSREG_CRM_SHIFT) |
1362 		(reg->Op2 << KVM_REG_ARM64_SYSREG_OP2_SHIFT));
1363 }
1364 
1365 static bool copy_reg_to_user(const struct sys_reg_desc *reg, u64 __user **uind)
1366 {
1367 	if (!*uind)
1368 		return true;
1369 
1370 	if (put_user(sys_reg_to_index(reg), *uind))
1371 		return false;
1372 
1373 	(*uind)++;
1374 	return true;
1375 }
1376 
1377 /* Assumed ordered tables, see kvm_sys_reg_table_init. */
1378 static int walk_sys_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
1379 {
1380 	const struct sys_reg_desc *i1, *i2, *end1, *end2;
1381 	unsigned int total = 0;
1382 	size_t num;
1383 
1384 	/* We check for duplicates here, to allow arch-specific overrides. */
1385 	i1 = get_target_table(vcpu->arch.target, true, &num);
1386 	end1 = i1 + num;
1387 	i2 = sys_reg_descs;
1388 	end2 = sys_reg_descs + ARRAY_SIZE(sys_reg_descs);
1389 
1390 	BUG_ON(i1 == end1 || i2 == end2);
1391 
1392 	/* Walk carefully, as both tables may refer to the same register. */
1393 	while (i1 || i2) {
1394 		int cmp = cmp_sys_reg(i1, i2);
1395 		/* target-specific overrides generic entry. */
1396 		if (cmp <= 0) {
1397 			/* Ignore registers we trap but don't save. */
1398 			if (i1->reg) {
1399 				if (!copy_reg_to_user(i1, &uind))
1400 					return -EFAULT;
1401 				total++;
1402 			}
1403 		} else {
1404 			/* Ignore registers we trap but don't save. */
1405 			if (i2->reg) {
1406 				if (!copy_reg_to_user(i2, &uind))
1407 					return -EFAULT;
1408 				total++;
1409 			}
1410 		}
1411 
1412 		if (cmp <= 0 && ++i1 == end1)
1413 			i1 = NULL;
1414 		if (cmp >= 0 && ++i2 == end2)
1415 			i2 = NULL;
1416 	}
1417 	return total;
1418 }
1419 
1420 unsigned long kvm_arm_num_sys_reg_descs(struct kvm_vcpu *vcpu)
1421 {
1422 	return ARRAY_SIZE(invariant_sys_regs)
1423 		+ num_demux_regs()
1424 		+ walk_sys_regs(vcpu, (u64 __user *)NULL);
1425 }
1426 
1427 int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
1428 {
1429 	unsigned int i;
1430 	int err;
1431 
1432 	/* Then give them all the invariant registers' indices. */
1433 	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++) {
1434 		if (put_user(sys_reg_to_index(&invariant_sys_regs[i]), uindices))
1435 			return -EFAULT;
1436 		uindices++;
1437 	}
1438 
1439 	err = walk_sys_regs(vcpu, uindices);
1440 	if (err < 0)
1441 		return err;
1442 	uindices += err;
1443 
1444 	return write_demux_regids(uindices);
1445 }
1446 
1447 static int check_sysreg_table(const struct sys_reg_desc *table, unsigned int n)
1448 {
1449 	unsigned int i;
1450 
1451 	for (i = 1; i < n; i++) {
1452 		if (cmp_sys_reg(&table[i-1], &table[i]) >= 0) {
1453 			kvm_err("sys_reg table %p out of order (%d)\n", table, i - 1);
1454 			return 1;
1455 		}
1456 	}
1457 
1458 	return 0;
1459 }
1460 
1461 void kvm_sys_reg_table_init(void)
1462 {
1463 	unsigned int i;
1464 	struct sys_reg_desc clidr;
1465 
1466 	/* Make sure tables are unique and in order. */
1467 	BUG_ON(check_sysreg_table(sys_reg_descs, ARRAY_SIZE(sys_reg_descs)));
1468 	BUG_ON(check_sysreg_table(cp14_regs, ARRAY_SIZE(cp14_regs)));
1469 	BUG_ON(check_sysreg_table(cp14_64_regs, ARRAY_SIZE(cp14_64_regs)));
1470 	BUG_ON(check_sysreg_table(cp15_regs, ARRAY_SIZE(cp15_regs)));
1471 	BUG_ON(check_sysreg_table(cp15_64_regs, ARRAY_SIZE(cp15_64_regs)));
1472 	BUG_ON(check_sysreg_table(invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs)));
1473 
1474 	/* We abuse the reset function to overwrite the table itself. */
1475 	for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++)
1476 		invariant_sys_regs[i].reset(NULL, &invariant_sys_regs[i]);
1477 
1478 	/*
1479 	 * CLIDR format is awkward, so clean it up.  See ARM B4.1.20:
1480 	 *
1481 	 *   If software reads the Cache Type fields from Ctype1
1482 	 *   upwards, once it has seen a value of 0b000, no caches
1483 	 *   exist at further-out levels of the hierarchy. So, for
1484 	 *   example, if Ctype3 is the first Cache Type field with a
1485 	 *   value of 0b000, the values of Ctype4 to Ctype7 must be
1486 	 *   ignored.
1487 	 */
1488 	get_clidr_el1(NULL, &clidr); /* Ugly... */
1489 	cache_levels = clidr.val;
1490 	for (i = 0; i < 7; i++)
1491 		if (((cache_levels >> (i*3)) & 7) == 0)
1492 			break;
1493 	/* Clear all higher bits. */
1494 	cache_levels &= (1 << (i*3))-1;
1495 }
1496 
1497 /**
1498  * kvm_reset_sys_regs - sets system registers to reset value
1499  * @vcpu: The VCPU pointer
1500  *
1501  * This function finds the right table above and sets the registers on the
1502  * virtual CPU struct to their architecturally defined reset values.
1503  */
1504 void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
1505 {
1506 	size_t num;
1507 	const struct sys_reg_desc *table;
1508 
1509 	/* Catch someone adding a register without putting in reset entry. */
1510 	memset(&vcpu->arch.ctxt.sys_regs, 0x42, sizeof(vcpu->arch.ctxt.sys_regs));
1511 
1512 	/* Generic chip reset first (so target could override). */
1513 	reset_sys_reg_descs(vcpu, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));
1514 
1515 	table = get_target_table(vcpu->arch.target, true, &num);
1516 	reset_sys_reg_descs(vcpu, table, num);
1517 
1518 	for (num = 1; num < NR_SYS_REGS; num++)
1519 		if (vcpu_sys_reg(vcpu, num) == 0x4242424242424242)
1520 			panic("Didn't reset vcpu_sys_reg(%zi)", num);
1521 }
1522