xref: /linux/tools/testing/selftests/kvm/lib/riscv/processor.c (revision f4b0c4b508364fde023e4f7b9f23f7e38c663dfe)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * RISC-V code
4  *
5  * Copyright (C) 2021 Western Digital Corporation or its affiliates.
6  */
7 
8 #include <linux/compiler.h>
9 #include <assert.h>
10 
11 #include "kvm_util.h"
12 #include "processor.h"
13 #include "ucall_common.h"
14 
15 #define DEFAULT_RISCV_GUEST_STACK_VADDR_MIN	0xac0000
16 
17 static vm_vaddr_t exception_handlers;
18 
__vcpu_has_ext(struct kvm_vcpu * vcpu,uint64_t ext)19 bool __vcpu_has_ext(struct kvm_vcpu *vcpu, uint64_t ext)
20 {
21 	unsigned long value = 0;
22 	int ret;
23 
24 	ret = __vcpu_get_reg(vcpu, ext, &value);
25 
26 	return !ret && !!value;
27 }
28 
page_align(struct kvm_vm * vm,uint64_t v)29 static uint64_t page_align(struct kvm_vm *vm, uint64_t v)
30 {
31 	return (v + vm->page_size) & ~(vm->page_size - 1);
32 }
33 
pte_addr(struct kvm_vm * vm,uint64_t entry)34 static uint64_t pte_addr(struct kvm_vm *vm, uint64_t entry)
35 {
36 	return ((entry & PGTBL_PTE_ADDR_MASK) >> PGTBL_PTE_ADDR_SHIFT) <<
37 		PGTBL_PAGE_SIZE_SHIFT;
38 }
39 
ptrs_per_pte(struct kvm_vm * vm)40 static uint64_t ptrs_per_pte(struct kvm_vm *vm)
41 {
42 	return PGTBL_PAGE_SIZE / sizeof(uint64_t);
43 }
44 
45 static uint64_t pte_index_mask[] = {
46 	PGTBL_L0_INDEX_MASK,
47 	PGTBL_L1_INDEX_MASK,
48 	PGTBL_L2_INDEX_MASK,
49 	PGTBL_L3_INDEX_MASK,
50 };
51 
52 static uint32_t pte_index_shift[] = {
53 	PGTBL_L0_INDEX_SHIFT,
54 	PGTBL_L1_INDEX_SHIFT,
55 	PGTBL_L2_INDEX_SHIFT,
56 	PGTBL_L3_INDEX_SHIFT,
57 };
58 
pte_index(struct kvm_vm * vm,vm_vaddr_t gva,int level)59 static uint64_t pte_index(struct kvm_vm *vm, vm_vaddr_t gva, int level)
60 {
61 	TEST_ASSERT(level > -1,
62 		"Negative page table level (%d) not possible", level);
63 	TEST_ASSERT(level < vm->pgtable_levels,
64 		"Invalid page table level (%d)", level);
65 
66 	return (gva & pte_index_mask[level]) >> pte_index_shift[level];
67 }
68 
virt_arch_pgd_alloc(struct kvm_vm * vm)69 void virt_arch_pgd_alloc(struct kvm_vm *vm)
70 {
71 	size_t nr_pages = page_align(vm, ptrs_per_pte(vm) * 8) / vm->page_size;
72 
73 	if (vm->pgd_created)
74 		return;
75 
76 	vm->pgd = vm_phy_pages_alloc(vm, nr_pages,
77 				     KVM_GUEST_PAGE_TABLE_MIN_PADDR,
78 				     vm->memslots[MEM_REGION_PT]);
79 	vm->pgd_created = true;
80 }
81 
virt_arch_pg_map(struct kvm_vm * vm,uint64_t vaddr,uint64_t paddr)82 void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
83 {
84 	uint64_t *ptep, next_ppn;
85 	int level = vm->pgtable_levels - 1;
86 
87 	TEST_ASSERT((vaddr % vm->page_size) == 0,
88 		"Virtual address not on page boundary,\n"
89 		"  vaddr: 0x%lx vm->page_size: 0x%x", vaddr, vm->page_size);
90 	TEST_ASSERT(sparsebit_is_set(vm->vpages_valid,
91 		(vaddr >> vm->page_shift)),
92 		"Invalid virtual address, vaddr: 0x%lx", vaddr);
93 	TEST_ASSERT((paddr % vm->page_size) == 0,
94 		"Physical address not on page boundary,\n"
95 		"  paddr: 0x%lx vm->page_size: 0x%x", paddr, vm->page_size);
96 	TEST_ASSERT((paddr >> vm->page_shift) <= vm->max_gfn,
97 		"Physical address beyond maximum supported,\n"
98 		"  paddr: 0x%lx vm->max_gfn: 0x%lx vm->page_size: 0x%x",
99 		paddr, vm->max_gfn, vm->page_size);
100 
101 	ptep = addr_gpa2hva(vm, vm->pgd) + pte_index(vm, vaddr, level) * 8;
102 	if (!*ptep) {
103 		next_ppn = vm_alloc_page_table(vm) >> PGTBL_PAGE_SIZE_SHIFT;
104 		*ptep = (next_ppn << PGTBL_PTE_ADDR_SHIFT) |
105 			PGTBL_PTE_VALID_MASK;
106 	}
107 	level--;
108 
109 	while (level > -1) {
110 		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) +
111 		       pte_index(vm, vaddr, level) * 8;
112 		if (!*ptep && level > 0) {
113 			next_ppn = vm_alloc_page_table(vm) >>
114 				   PGTBL_PAGE_SIZE_SHIFT;
115 			*ptep = (next_ppn << PGTBL_PTE_ADDR_SHIFT) |
116 				PGTBL_PTE_VALID_MASK;
117 		}
118 		level--;
119 	}
120 
121 	paddr = paddr >> PGTBL_PAGE_SIZE_SHIFT;
122 	*ptep = (paddr << PGTBL_PTE_ADDR_SHIFT) |
123 		PGTBL_PTE_PERM_MASK | PGTBL_PTE_VALID_MASK;
124 }
125 
addr_arch_gva2gpa(struct kvm_vm * vm,vm_vaddr_t gva)126 vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
127 {
128 	uint64_t *ptep;
129 	int level = vm->pgtable_levels - 1;
130 
131 	if (!vm->pgd_created)
132 		goto unmapped_gva;
133 
134 	ptep = addr_gpa2hva(vm, vm->pgd) + pte_index(vm, gva, level) * 8;
135 	if (!ptep)
136 		goto unmapped_gva;
137 	level--;
138 
139 	while (level > -1) {
140 		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) +
141 		       pte_index(vm, gva, level) * 8;
142 		if (!ptep)
143 			goto unmapped_gva;
144 		level--;
145 	}
146 
147 	return pte_addr(vm, *ptep) + (gva & (vm->page_size - 1));
148 
149 unmapped_gva:
150 	TEST_FAIL("No mapping for vm virtual address gva: 0x%lx level: %d",
151 		  gva, level);
152 	exit(1);
153 }
154 
pte_dump(FILE * stream,struct kvm_vm * vm,uint8_t indent,uint64_t page,int level)155 static void pte_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent,
156 		     uint64_t page, int level)
157 {
158 #ifdef DEBUG
159 	static const char *const type[] = { "pte", "pmd", "pud", "p4d"};
160 	uint64_t pte, *ptep;
161 
162 	if (level < 0)
163 		return;
164 
165 	for (pte = page; pte < page + ptrs_per_pte(vm) * 8; pte += 8) {
166 		ptep = addr_gpa2hva(vm, pte);
167 		if (!*ptep)
168 			continue;
169 		fprintf(stream, "%*s%s: %lx: %lx at %p\n", indent, "",
170 			type[level], pte, *ptep, ptep);
171 		pte_dump(stream, vm, indent + 1,
172 			 pte_addr(vm, *ptep), level - 1);
173 	}
174 #endif
175 }
176 
virt_arch_dump(FILE * stream,struct kvm_vm * vm,uint8_t indent)177 void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
178 {
179 	int level = vm->pgtable_levels - 1;
180 	uint64_t pgd, *ptep;
181 
182 	if (!vm->pgd_created)
183 		return;
184 
185 	for (pgd = vm->pgd; pgd < vm->pgd + ptrs_per_pte(vm) * 8; pgd += 8) {
186 		ptep = addr_gpa2hva(vm, pgd);
187 		if (!*ptep)
188 			continue;
189 		fprintf(stream, "%*spgd: %lx: %lx at %p\n", indent, "",
190 			pgd, *ptep, ptep);
191 		pte_dump(stream, vm, indent + 1,
192 			 pte_addr(vm, *ptep), level - 1);
193 	}
194 }
195 
riscv_vcpu_mmu_setup(struct kvm_vcpu * vcpu)196 void riscv_vcpu_mmu_setup(struct kvm_vcpu *vcpu)
197 {
198 	struct kvm_vm *vm = vcpu->vm;
199 	unsigned long satp;
200 
201 	/*
202 	 * The RISC-V Sv48 MMU mode supports 56-bit physical address
203 	 * for 48-bit virtual address with 4KB last level page size.
204 	 */
205 	switch (vm->mode) {
206 	case VM_MODE_P52V48_4K:
207 	case VM_MODE_P48V48_4K:
208 	case VM_MODE_P40V48_4K:
209 		break;
210 	default:
211 		TEST_FAIL("Unknown guest mode, mode: 0x%x", vm->mode);
212 	}
213 
214 	satp = (vm->pgd >> PGTBL_PAGE_SIZE_SHIFT) & SATP_PPN;
215 	satp |= SATP_MODE_48;
216 
217 	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(satp), satp);
218 }
219 
vcpu_arch_dump(FILE * stream,struct kvm_vcpu * vcpu,uint8_t indent)220 void vcpu_arch_dump(FILE *stream, struct kvm_vcpu *vcpu, uint8_t indent)
221 {
222 	struct kvm_riscv_core core;
223 
224 	vcpu_get_reg(vcpu, RISCV_CORE_REG(mode), &core.mode);
225 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.pc), &core.regs.pc);
226 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.ra), &core.regs.ra);
227 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.sp), &core.regs.sp);
228 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.gp), &core.regs.gp);
229 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.tp), &core.regs.tp);
230 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t0), &core.regs.t0);
231 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t1), &core.regs.t1);
232 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t2), &core.regs.t2);
233 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s0), &core.regs.s0);
234 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s1), &core.regs.s1);
235 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a0), &core.regs.a0);
236 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a1), &core.regs.a1);
237 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a2), &core.regs.a2);
238 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a3), &core.regs.a3);
239 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a4), &core.regs.a4);
240 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a5), &core.regs.a5);
241 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a6), &core.regs.a6);
242 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.a7), &core.regs.a7);
243 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s2), &core.regs.s2);
244 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s3), &core.regs.s3);
245 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s4), &core.regs.s4);
246 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s5), &core.regs.s5);
247 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s6), &core.regs.s6);
248 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s7), &core.regs.s7);
249 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s8), &core.regs.s8);
250 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s9), &core.regs.s9);
251 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s10), &core.regs.s10);
252 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.s11), &core.regs.s11);
253 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t3), &core.regs.t3);
254 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t4), &core.regs.t4);
255 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t5), &core.regs.t5);
256 	vcpu_get_reg(vcpu, RISCV_CORE_REG(regs.t6), &core.regs.t6);
257 
258 	fprintf(stream,
259 		" MODE:  0x%lx\n", core.mode);
260 	fprintf(stream,
261 		" PC: 0x%016lx   RA: 0x%016lx SP: 0x%016lx GP: 0x%016lx\n",
262 		core.regs.pc, core.regs.ra, core.regs.sp, core.regs.gp);
263 	fprintf(stream,
264 		" TP: 0x%016lx   T0: 0x%016lx T1: 0x%016lx T2: 0x%016lx\n",
265 		core.regs.tp, core.regs.t0, core.regs.t1, core.regs.t2);
266 	fprintf(stream,
267 		" S0: 0x%016lx   S1: 0x%016lx A0: 0x%016lx A1: 0x%016lx\n",
268 		core.regs.s0, core.regs.s1, core.regs.a0, core.regs.a1);
269 	fprintf(stream,
270 		" A2: 0x%016lx   A3: 0x%016lx A4: 0x%016lx A5: 0x%016lx\n",
271 		core.regs.a2, core.regs.a3, core.regs.a4, core.regs.a5);
272 	fprintf(stream,
273 		" A6: 0x%016lx   A7: 0x%016lx S2: 0x%016lx S3: 0x%016lx\n",
274 		core.regs.a6, core.regs.a7, core.regs.s2, core.regs.s3);
275 	fprintf(stream,
276 		" S4: 0x%016lx   S5: 0x%016lx S6: 0x%016lx S7: 0x%016lx\n",
277 		core.regs.s4, core.regs.s5, core.regs.s6, core.regs.s7);
278 	fprintf(stream,
279 		" S8: 0x%016lx   S9: 0x%016lx S10: 0x%016lx S11: 0x%016lx\n",
280 		core.regs.s8, core.regs.s9, core.regs.s10, core.regs.s11);
281 	fprintf(stream,
282 		" T3: 0x%016lx   T4: 0x%016lx T5: 0x%016lx T6: 0x%016lx\n",
283 		core.regs.t3, core.regs.t4, core.regs.t5, core.regs.t6);
284 }
285 
guest_unexp_trap(void)286 static void __aligned(16) guest_unexp_trap(void)
287 {
288 	sbi_ecall(KVM_RISCV_SELFTESTS_SBI_EXT,
289 		  KVM_RISCV_SELFTESTS_SBI_UNEXP,
290 		  0, 0, 0, 0, 0, 0);
291 }
292 
vcpu_arch_set_entry_point(struct kvm_vcpu * vcpu,void * guest_code)293 void vcpu_arch_set_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
294 {
295 	vcpu_set_reg(vcpu, RISCV_CORE_REG(regs.pc), (unsigned long)guest_code);
296 }
297 
vm_arch_vcpu_add(struct kvm_vm * vm,uint32_t vcpu_id)298 struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id)
299 {
300 	int r;
301 	size_t stack_size;
302 	unsigned long stack_vaddr;
303 	unsigned long current_gp = 0;
304 	struct kvm_mp_state mps;
305 	struct kvm_vcpu *vcpu;
306 
307 	stack_size = vm->page_size == 4096 ? DEFAULT_STACK_PGS * vm->page_size :
308 					     vm->page_size;
309 	stack_vaddr = __vm_vaddr_alloc(vm, stack_size,
310 				       DEFAULT_RISCV_GUEST_STACK_VADDR_MIN,
311 				       MEM_REGION_DATA);
312 
313 	vcpu = __vm_vcpu_add(vm, vcpu_id);
314 	riscv_vcpu_mmu_setup(vcpu);
315 
316 	/*
317 	 * With SBI HSM support in KVM RISC-V, all secondary VCPUs are
318 	 * powered-off by default so we ensure that all secondary VCPUs
319 	 * are powered-on using KVM_SET_MP_STATE ioctl().
320 	 */
321 	mps.mp_state = KVM_MP_STATE_RUNNABLE;
322 	r = __vcpu_ioctl(vcpu, KVM_SET_MP_STATE, &mps);
323 	TEST_ASSERT(!r, "IOCTL KVM_SET_MP_STATE failed (error %d)", r);
324 
325 	/* Setup global pointer of guest to be same as the host */
326 	asm volatile (
327 		"add %0, gp, zero" : "=r" (current_gp) : : "memory");
328 	vcpu_set_reg(vcpu, RISCV_CORE_REG(regs.gp), current_gp);
329 
330 	/* Setup stack pointer and program counter of guest */
331 	vcpu_set_reg(vcpu, RISCV_CORE_REG(regs.sp), stack_vaddr + stack_size);
332 
333 	/* Setup sscratch for guest_get_vcpuid() */
334 	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(sscratch), vcpu_id);
335 
336 	/* Setup default exception vector of guest */
337 	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(stvec), (unsigned long)guest_unexp_trap);
338 
339 	return vcpu;
340 }
341 
vcpu_args_set(struct kvm_vcpu * vcpu,unsigned int num,...)342 void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
343 {
344 	va_list ap;
345 	uint64_t id = RISCV_CORE_REG(regs.a0);
346 	int i;
347 
348 	TEST_ASSERT(num >= 1 && num <= 8, "Unsupported number of args,\n"
349 		    "  num: %u", num);
350 
351 	va_start(ap, num);
352 
353 	for (i = 0; i < num; i++) {
354 		switch (i) {
355 		case 0:
356 			id = RISCV_CORE_REG(regs.a0);
357 			break;
358 		case 1:
359 			id = RISCV_CORE_REG(regs.a1);
360 			break;
361 		case 2:
362 			id = RISCV_CORE_REG(regs.a2);
363 			break;
364 		case 3:
365 			id = RISCV_CORE_REG(regs.a3);
366 			break;
367 		case 4:
368 			id = RISCV_CORE_REG(regs.a4);
369 			break;
370 		case 5:
371 			id = RISCV_CORE_REG(regs.a5);
372 			break;
373 		case 6:
374 			id = RISCV_CORE_REG(regs.a6);
375 			break;
376 		case 7:
377 			id = RISCV_CORE_REG(regs.a7);
378 			break;
379 		}
380 		vcpu_set_reg(vcpu, id, va_arg(ap, uint64_t));
381 	}
382 
383 	va_end(ap);
384 }
385 
kvm_exit_unexpected_exception(int vector,int ec)386 void kvm_exit_unexpected_exception(int vector, int ec)
387 {
388 	ucall(UCALL_UNHANDLED, 2, vector, ec);
389 }
390 
assert_on_unhandled_exception(struct kvm_vcpu * vcpu)391 void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
392 {
393 	struct ucall uc;
394 
395 	if (get_ucall(vcpu, &uc) == UCALL_UNHANDLED) {
396 		TEST_FAIL("Unexpected exception (vector:0x%lx, ec:0x%lx)",
397 			uc.args[0], uc.args[1]);
398 	}
399 }
400 
401 struct handlers {
402 	exception_handler_fn exception_handlers[NR_VECTORS][NR_EXCEPTIONS];
403 };
404 
route_exception(struct ex_regs * regs)405 void route_exception(struct ex_regs *regs)
406 {
407 	struct handlers *handlers = (struct handlers *)exception_handlers;
408 	int vector = 0, ec;
409 
410 	ec = regs->cause & ~CAUSE_IRQ_FLAG;
411 	if (ec >= NR_EXCEPTIONS)
412 		goto unexpected_exception;
413 
414 	/* Use the same handler for all the interrupts */
415 	if (regs->cause & CAUSE_IRQ_FLAG) {
416 		vector = 1;
417 		ec = 0;
418 	}
419 
420 	if (handlers && handlers->exception_handlers[vector][ec])
421 		return handlers->exception_handlers[vector][ec](regs);
422 
423 unexpected_exception:
424 	return kvm_exit_unexpected_exception(vector, ec);
425 }
426 
vcpu_init_vector_tables(struct kvm_vcpu * vcpu)427 void vcpu_init_vector_tables(struct kvm_vcpu *vcpu)
428 {
429 	extern char exception_vectors;
430 
431 	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(stvec), (unsigned long)&exception_vectors);
432 }
433 
vm_init_vector_tables(struct kvm_vm * vm)434 void vm_init_vector_tables(struct kvm_vm *vm)
435 {
436 	vm->handlers = __vm_vaddr_alloc(vm, sizeof(struct handlers),
437 				   vm->page_size, MEM_REGION_DATA);
438 
439 	*(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers;
440 }
441 
vm_install_exception_handler(struct kvm_vm * vm,int vector,exception_handler_fn handler)442 void vm_install_exception_handler(struct kvm_vm *vm, int vector, exception_handler_fn handler)
443 {
444 	struct handlers *handlers = addr_gva2hva(vm, vm->handlers);
445 
446 	assert(vector < NR_EXCEPTIONS);
447 	handlers->exception_handlers[0][vector] = handler;
448 }
449 
vm_install_interrupt_handler(struct kvm_vm * vm,exception_handler_fn handler)450 void vm_install_interrupt_handler(struct kvm_vm *vm, exception_handler_fn handler)
451 {
452 	struct handlers *handlers = addr_gva2hva(vm, vm->handlers);
453 
454 	handlers->exception_handlers[1][0] = handler;
455 }
456 
guest_get_vcpuid(void)457 uint32_t guest_get_vcpuid(void)
458 {
459 	return csr_read(CSR_SSCRATCH);
460 }
461 
sbi_ecall(int ext,int fid,unsigned long arg0,unsigned long arg1,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)462 struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
463 			unsigned long arg1, unsigned long arg2,
464 			unsigned long arg3, unsigned long arg4,
465 			unsigned long arg5)
466 {
467 	register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);
468 	register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);
469 	register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);
470 	register uintptr_t a3 asm ("a3") = (uintptr_t)(arg3);
471 	register uintptr_t a4 asm ("a4") = (uintptr_t)(arg4);
472 	register uintptr_t a5 asm ("a5") = (uintptr_t)(arg5);
473 	register uintptr_t a6 asm ("a6") = (uintptr_t)(fid);
474 	register uintptr_t a7 asm ("a7") = (uintptr_t)(ext);
475 	struct sbiret ret;
476 
477 	asm volatile (
478 		"ecall"
479 		: "+r" (a0), "+r" (a1)
480 		: "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7)
481 		: "memory");
482 	ret.error = a0;
483 	ret.value = a1;
484 
485 	return ret;
486 }
487 
guest_sbi_probe_extension(int extid,long * out_val)488 bool guest_sbi_probe_extension(int extid, long *out_val)
489 {
490 	struct sbiret ret;
491 
492 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid,
493 			0, 0, 0, 0, 0);
494 
495 	__GUEST_ASSERT(!ret.error || ret.error == SBI_ERR_NOT_SUPPORTED,
496 		       "ret.error=%ld, ret.value=%ld\n", ret.error, ret.value);
497 
498 	if (ret.error == SBI_ERR_NOT_SUPPORTED)
499 		return false;
500 
501 	if (out_val)
502 		*out_val = ret.value;
503 
504 	return true;
505 }
506 
get_host_sbi_spec_version(void)507 unsigned long get_host_sbi_spec_version(void)
508 {
509 	struct sbiret ret;
510 
511 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION, 0,
512 		       0, 0, 0, 0, 0);
513 
514 	GUEST_ASSERT(!ret.error);
515 
516 	return ret.value;
517 }
518