Add core KVM selftests support for LoongArch, it includes exception handler, mmu page table setup and vcpu startup entry supporting etc.
Signed-off-by: Bibo Mao maobibo@loongson.cn --- .../selftests/kvm/lib/loongarch/exception.S | 59 +++ .../selftests/kvm/lib/loongarch/processor.c | 349 ++++++++++++++++++ 2 files changed, 408 insertions(+) create mode 100644 tools/testing/selftests/kvm/lib/loongarch/exception.S create mode 100644 tools/testing/selftests/kvm/lib/loongarch/processor.c
diff --git a/tools/testing/selftests/kvm/lib/loongarch/exception.S b/tools/testing/selftests/kvm/lib/loongarch/exception.S new file mode 100644 index 000000000000..88bfa505c6f5 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/loongarch/exception.S @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include "processor.h" + +/* address of refill exception should be 4K aligned */ +.balign 4096 +.global handle_tlb_refill +handle_tlb_refill: + csrwr t0, LOONGARCH_CSR_TLBRSAVE + csrrd t0, LOONGARCH_CSR_PGD + lddir t0, t0, 3 + lddir t0, t0, 1 + ldpte t0, 0 + ldpte t0, 1 + tlbfill + csrrd t0, LOONGARCH_CSR_TLBRSAVE + ertn + + /* + * save and restore all gprs except base register, + * and default value of base register is sp ($r3). + */ +.macro save_gprs base + .irp n,1,2,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 + st.d $r\n, \base, 8 * \n + .endr +.endm + +.macro restore_gprs base + .irp n,1,2,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 + ld.d $r\n, \base, 8 * \n + .endr +.endm + +/* address of general exception should be 4K aligned */ +.balign 4096 +.global handle_exception +handle_exception: + csrwr sp, LOONGARCH_CSR_KS0 + csrrd sp, LOONGARCH_CSR_KS1 + addi.d sp, sp, -EXREGS_SIZE + + save_gprs sp + /* save sp register to stack */ + csrrd t0, LOONGARCH_CSR_KS0 + st.d t0, sp, 3 * 8 + + csrrd t0, LOONGARCH_CSR_ERA + st.d t0, sp, PC_OFFSET_EXREGS + csrrd t0, LOONGARCH_CSR_ESTAT + st.d t0, sp, ESTAT_OFFSET_EXREGS + csrrd t0, LOONGARCH_CSR_BADV + st.d t0, sp, BADV_OFFSET_EXREGS + + or a0, sp, zero + bl route_exception + restore_gprs sp + csrrd sp, LOONGARCH_CSR_KS0 + ertn diff --git a/tools/testing/selftests/kvm/lib/loongarch/processor.c b/tools/testing/selftests/kvm/lib/loongarch/processor.c new file mode 100644 index 000000000000..25b7f896a107 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/loongarch/processor.c @@ -0,0 +1,349 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <assert.h> +#include <linux/compiler.h> + +#include "kvm_util.h" +#include "processor.h" +#include "ucall_common.h" + +#define LOONGARCH_GUEST_STACK_VADDR_MIN 0x200000 +#define LOONARCH_PAGE_TABLE_PHYS_MIN 0x200000 + +static vm_paddr_t invalid_pgtable[4]; +static uint64_t virt_pte_index(struct kvm_vm *vm, vm_vaddr_t gva, int level) +{ + unsigned int shift; + uint64_t mask; + + shift = level * (vm->page_shift - 3) + vm->page_shift; + mask = (1UL << (vm->page_shift - 3)) - 1; + return (gva >> shift) & mask; +} + +static uint64_t pte_addr(struct kvm_vm *vm, uint64_t entry) +{ + return entry & ~((0x1UL << vm->page_shift) - 1); +} + +static uint64_t ptrs_per_pte(struct kvm_vm *vm) +{ + return 1 << (vm->page_shift - 3); +} + +static void virt_set_pgtable(struct kvm_vm *vm, vm_paddr_t table, vm_paddr_t child) +{ + uint64_t *ptep; + int i, ptrs_per_pte; + + ptep = addr_gpa2hva(vm, table); + ptrs_per_pte = 1 << (vm->page_shift - 3); + for (i = 0; i < ptrs_per_pte; i++) + WRITE_ONCE(*(ptep + i), child); +} + +void virt_arch_pgd_alloc(struct kvm_vm *vm) +{ + int i; + vm_paddr_t child, table; + + if (vm->pgd_created) + return; + child = table = 0; + for (i = 0; i < vm->pgtable_levels; i++) { + invalid_pgtable[i] = child; + table = vm_phy_page_alloc(vm, LOONARCH_PAGE_TABLE_PHYS_MIN, + vm->memslots[MEM_REGION_PT]); + TEST_ASSERT(table, "Fail to allocate page tale at level %d\n", i); + virt_set_pgtable(vm, table, child); + child = table; + } + vm->pgd = table; + vm->pgd_created = true; +} + +static int virt_pte_none(uint64_t *ptep, int level) +{ + return *ptep == invalid_pgtable[level]; +} + +static uint64_t *virt_populate_pte(struct kvm_vm *vm, vm_vaddr_t gva, int alloc) +{ + uint64_t *ptep; + vm_paddr_t child; + int level; + + if (!vm->pgd_created) + goto unmapped_gva; + + level = vm->pgtable_levels - 1; + child = vm->pgd; + while (level > 0) { + ptep = addr_gpa2hva(vm, child) + virt_pte_index(vm, gva, level) * 8; + if (virt_pte_none(ptep, level)) { + if (alloc) { + child = vm_alloc_page_table(vm); + virt_set_pgtable(vm, child, invalid_pgtable[level - 1]); + WRITE_ONCE(*ptep, child); + } else + goto unmapped_gva; + + } else + child = pte_addr(vm, *ptep); + level--; + } + + ptep = addr_gpa2hva(vm, child) + virt_pte_index(vm, gva, level) * 8; + return ptep; + +unmapped_gva: + TEST_FAIL("No mapping for vm virtual address, gva: 0x%lx", gva); + exit(EXIT_FAILURE); +} + +vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) +{ + uint64_t *ptep; + + ptep = virt_populate_pte(vm, gva, 0); + TEST_ASSERT(*ptep != 0, "Virtual address vaddr: 0x%lx not mapped\n", gva); + + return pte_addr(vm, *ptep) + (gva & (vm->page_size - 1)); +} + +void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr) +{ + uint32_t prot_bits; + uint64_t *ptep; + + TEST_ASSERT((vaddr % vm->page_size) == 0, + "Virtual address not on page boundary,\n" + "vaddr: 0x%lx vm->page_size: 0x%x", vaddr, vm->page_size); + TEST_ASSERT(sparsebit_is_set(vm->vpages_valid, + (vaddr >> vm->page_shift)), + "Invalid virtual address, vaddr: 0x%lx", vaddr); + TEST_ASSERT((paddr % vm->page_size) == 0, + "Physical address not on page boundary,\n" + "paddr: 0x%lx vm->page_size: 0x%x", paddr, vm->page_size); + TEST_ASSERT((paddr >> vm->page_shift) <= vm->max_gfn, + "Physical address beyond maximum supported,\n" + "paddr: 0x%lx vm->max_gfn: 0x%lx vm->page_size: 0x%x", + paddr, vm->max_gfn, vm->page_size); + + ptep = virt_populate_pte(vm, vaddr, 1); + prot_bits = _PAGE_PRESENT | __READABLE | __WRITEABLE | _CACHE_CC; + prot_bits |= _PAGE_USER; + WRITE_ONCE(*ptep, paddr | prot_bits); +} + +static void pte_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent, uint64_t page, int level) +{ + static const char * const type[] = { "pte", "pmd", "pud", "pgd"}; + uint64_t pte, *ptep; + + if (level < 0) + return; + + for (pte = page; pte < page + ptrs_per_pte(vm) * 8; pte += 8) { + ptep = addr_gpa2hva(vm, pte); + if (virt_pte_none(ptep, level)) + continue; + fprintf(stream, "%*s%s: %lx: %lx at %p\n", + indent, "", type[level], pte, *ptep, ptep); + pte_dump(stream, vm, indent + 1, pte_addr(vm, *ptep), level--); + } +} + +void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent) +{ + int level; + + if (!vm->pgd_created) + return; + + level = vm->pgtable_levels - 1; + pte_dump(stream, vm, indent, vm->pgd, level); +} + +void vcpu_arch_dump(FILE *stream, struct kvm_vcpu *vcpu, uint8_t indent) +{ +} + +void assert_on_unhandled_exception(struct kvm_vcpu *vcpu) +{ + struct ucall uc; + + if (get_ucall(vcpu, &uc) != UCALL_UNHANDLED) + return; + + TEST_FAIL("Unexpected exception (pc:0x%lx, estat:0x%lx, badv:0x%lx)", + uc.args[0], uc.args[1], uc.args[2]); +} + +void route_exception(struct ex_regs *regs) +{ + unsigned long pc, estat, badv; + + pc = regs->pc; + estat = regs->estat; + badv = regs->badv; + ucall(UCALL_UNHANDLED, 3, pc, estat, badv); + while (1) + ; +} + +void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...) +{ + va_list ap; + struct kvm_regs regs; + int i; + + TEST_ASSERT(num >= 1 && num <= 8, "Unsupported number of args,\n" + "num: %u\n", num); + + vcpu_regs_get(vcpu, ®s); + va_start(ap, num); + for (i = 0; i < num; i++) + regs.gpr[i + 4] = va_arg(ap, uint64_t); + va_end(ap); + vcpu_regs_set(vcpu, ®s); +} + +static void loongarch_get_csr(struct kvm_vcpu *vcpu, uint64_t id, void *addr) +{ + uint64_t csrid; + + csrid = KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | 8 * id; + __vcpu_get_reg(vcpu, csrid, addr); +} + +static void loongarch_set_csr(struct kvm_vcpu *vcpu, uint64_t id, uint64_t val) +{ + uint64_t csrid; + + csrid = KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | 8 * id; + vcpu_set_reg(vcpu, csrid, val); +} + +static void loongarch_vcpu_setup(struct kvm_vcpu *vcpu) +{ + unsigned long val; + int width; + struct kvm_vm *vm = vcpu->vm; + + switch (vm->mode) { + case VM_MODE_P48V48_16K: + case VM_MODE_P40V48_16K: + case VM_MODE_P36V48_16K: + case VM_MODE_P36V47_16K: + break; + + default: + TEST_FAIL("Unknown guest mode, mode: 0x%x", vm->mode); + } + + /* user mode and page enable mode */ + val = PLV_USER | CSR_CRMD_PG; + loongarch_set_csr(vcpu, LOONGARCH_CSR_CRMD, val); + loongarch_set_csr(vcpu, LOONGARCH_CSR_PRMD, val); + loongarch_set_csr(vcpu, LOONGARCH_CSR_EUEN, 1); + loongarch_set_csr(vcpu, LOONGARCH_CSR_ECFG, 0); + loongarch_set_csr(vcpu, LOONGARCH_CSR_TCFG, 0); + loongarch_set_csr(vcpu, LOONGARCH_CSR_ASID, 1); + + width = vm->page_shift - 3; + val = 0; + switch (vm->pgtable_levels) { + case 4: + /* pud page shift and width */ + val = (vm->page_shift + width * 2) << 20 | (width << 25); + /* fall throuth */ + case 3: + /* pmd page shift and width */ + val |= (vm->page_shift + width) << 10 | (width << 15); + /* pte page shift and width */ + val |= vm->page_shift | width << 5; + break; + default: + TEST_FAIL("Got %u page table levels, expected 3 or 4", vm->pgtable_levels); + } + loongarch_set_csr(vcpu, LOONGARCH_CSR_PWCTL0, val); + + /* PGD page shift and width */ + val = (vm->page_shift + width * (vm->pgtable_levels - 1)) | width << 6; + loongarch_set_csr(vcpu, LOONGARCH_CSR_PWCTL1, val); + loongarch_set_csr(vcpu, LOONGARCH_CSR_PGDL, vm->pgd); + + /* + * Refill exception runs on real mode + * Entry address should be physical address + */ + val = addr_gva2gpa(vm, (unsigned long)handle_tlb_refill); + loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBRENTRY, val); + + /* + * General exception runs on page-enabled mode + * Entry address should be virtual address + */ + val = (unsigned long)handle_exception; + loongarch_set_csr(vcpu, LOONGARCH_CSR_EENTRY, val); + + loongarch_get_csr(vcpu, LOONGARCH_CSR_TLBIDX, &val); + val &= ~CSR_TLBIDX_SIZEM; + val |= PS_DEFAULT_SIZE << CSR_TLBIDX_SIZE; + loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBIDX, val); + + loongarch_set_csr(vcpu, LOONGARCH_CSR_STLBPGSIZE, PS_DEFAULT_SIZE); + + /* LOONGARCH_CSR_KS1 is used for exception stack */ + val = __vm_vaddr_alloc(vm, vm->page_size, + LOONGARCH_GUEST_STACK_VADDR_MIN, MEM_REGION_DATA); + TEST_ASSERT(val != 0, "No memory for exception stack"); + val = val + vm->page_size; + loongarch_set_csr(vcpu, LOONGARCH_CSR_KS1, val); + + loongarch_get_csr(vcpu, LOONGARCH_CSR_TLBREHI, &val); + val &= ~CSR_TLBREHI_PS; + val |= PS_DEFAULT_SIZE << CSR_TLBREHI_PS_SHIFT; + loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBREHI, val); + + loongarch_set_csr(vcpu, LOONGARCH_CSR_CPUID, vcpu->id); + loongarch_set_csr(vcpu, LOONGARCH_CSR_TMID, vcpu->id); +} + +static struct kvm_vcpu *loongarch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id) +{ + size_t stack_size; + uint64_t stack_vaddr; + struct kvm_regs regs; + struct kvm_vcpu *vcpu; + + vcpu = __vm_vcpu_add(vm, vcpu_id); + stack_size = vm->page_size; + stack_vaddr = __vm_vaddr_alloc(vm, stack_size, + LOONGARCH_GUEST_STACK_VADDR_MIN, MEM_REGION_DATA); + TEST_ASSERT(stack_vaddr != 0, "No memory for vm stack"); + + loongarch_vcpu_setup(vcpu); + /* Setup guest general purpose registers */ + vcpu_regs_get(vcpu, ®s); + regs.gpr[3] = stack_vaddr + stack_size; + vcpu_regs_set(vcpu, ®s); + + return vcpu; +} + +struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id) +{ + return loongarch_vcpu_add(vm, vcpu_id); +} + +void vcpu_arch_set_entry_point(struct kvm_vcpu *vcpu, void *guest_code) +{ + struct kvm_regs regs; + + /* Setup guest PC register */ + vcpu_regs_get(vcpu, ®s); + regs.pc = (uint64_t)guest_code; + vcpu_regs_set(vcpu, ®s); +}