From: Tianrui Zhao <zhaotian...@loongson.cn>

Add core KVM selftests support for LoongArch, it includes exception
handler, mmu page table setup and vcpu startup entry supporting etc.

Signed-off-by: Tianrui Zhao <zhaotian...@loongson.cn>
Signed-off-by: Bibo Mao <maob...@loongson.cn>
---
 .../selftests/kvm/lib/loongarch/exception.S   |  59 ++++
 .../selftests/kvm/lib/loongarch/processor.c   | 332 ++++++++++++++++++
 2 files changed, 391 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..e6d1cd549944
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/loongarch/processor.c
@@ -0,0 +1,332 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <assert.h>
+#include <linux/compiler.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+
+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++)
+               *(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, DEFAULT_LOONARCH64_PAGE_TABLE_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]);
+                               *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;
+       *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, &regs);
+       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, &regs);
+}
+
+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,
+                       DEFAULT_LOONARCH64_STACK_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);
+}
+
+struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
+                                 void *guest_code)
+{
+       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,
+                       DEFAULT_LOONARCH64_STACK_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, &regs);
+       regs.gpr[3] = stack_vaddr + stack_size;
+       regs.pc = (uint64_t)guest_code;
+       vcpu_regs_set(vcpu, &regs);
+
+       return vcpu;
+}
-- 
2.39.3


Reply via email to