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-rw-r--r--arch/riscv/kvm/main.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
new file mode 100644
index 0000000000..48ae0d4b39
--- /dev/null
+++ b/arch/riscv/kvm/main.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ * Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kvm_host.h>
+#include <asm/csr.h>
+#include <asm/hwcap.h>
+#include <asm/sbi.h>
+
+long kvm_arch_dev_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_hardware_enable(void)
+{
+ unsigned long hideleg, hedeleg;
+
+ hedeleg = 0;
+ hedeleg |= (1UL << EXC_INST_MISALIGNED);
+ hedeleg |= (1UL << EXC_BREAKPOINT);
+ hedeleg |= (1UL << EXC_SYSCALL);
+ hedeleg |= (1UL << EXC_INST_PAGE_FAULT);
+ hedeleg |= (1UL << EXC_LOAD_PAGE_FAULT);
+ hedeleg |= (1UL << EXC_STORE_PAGE_FAULT);
+ csr_write(CSR_HEDELEG, hedeleg);
+
+ hideleg = 0;
+ hideleg |= (1UL << IRQ_VS_SOFT);
+ hideleg |= (1UL << IRQ_VS_TIMER);
+ hideleg |= (1UL << IRQ_VS_EXT);
+ csr_write(CSR_HIDELEG, hideleg);
+
+ /* VS should access only the time counter directly. Everything else should trap */
+ csr_write(CSR_HCOUNTEREN, 0x02);
+
+ csr_write(CSR_HVIP, 0);
+
+ kvm_riscv_aia_enable();
+
+ return 0;
+}
+
+void kvm_arch_hardware_disable(void)
+{
+ kvm_riscv_aia_disable();
+
+ /*
+ * After clearing the hideleg CSR, the host kernel will receive
+ * spurious interrupts if hvip CSR has pending interrupts and the
+ * corresponding enable bits in vsie CSR are asserted. To avoid it,
+ * hvip CSR and vsie CSR must be cleared before clearing hideleg CSR.
+ */
+ csr_write(CSR_VSIE, 0);
+ csr_write(CSR_HVIP, 0);
+ csr_write(CSR_HEDELEG, 0);
+ csr_write(CSR_HIDELEG, 0);
+}
+
+static int __init riscv_kvm_init(void)
+{
+ int rc;
+ const char *str;
+
+ if (!riscv_isa_extension_available(NULL, h)) {
+ kvm_info("hypervisor extension not available\n");
+ return -ENODEV;
+ }
+
+ if (sbi_spec_is_0_1()) {
+ kvm_info("require SBI v0.2 or higher\n");
+ return -ENODEV;
+ }
+
+ if (!sbi_probe_extension(SBI_EXT_RFENCE)) {
+ kvm_info("require SBI RFENCE extension\n");
+ return -ENODEV;
+ }
+
+ kvm_riscv_gstage_mode_detect();
+
+ kvm_riscv_gstage_vmid_detect();
+
+ rc = kvm_riscv_aia_init();
+ if (rc && rc != -ENODEV)
+ return rc;
+
+ kvm_info("hypervisor extension available\n");
+
+ switch (kvm_riscv_gstage_mode()) {
+ case HGATP_MODE_SV32X4:
+ str = "Sv32x4";
+ break;
+ case HGATP_MODE_SV39X4:
+ str = "Sv39x4";
+ break;
+ case HGATP_MODE_SV48X4:
+ str = "Sv48x4";
+ break;
+ case HGATP_MODE_SV57X4:
+ str = "Sv57x4";
+ break;
+ default:
+ return -ENODEV;
+ }
+ kvm_info("using %s G-stage page table format\n", str);
+
+ kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
+
+ if (kvm_riscv_aia_available())
+ kvm_info("AIA available with %d guest external interrupts\n",
+ kvm_riscv_aia_nr_hgei);
+
+ rc = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ if (rc) {
+ kvm_riscv_aia_exit();
+ return rc;
+ }
+
+ return 0;
+}
+module_init(riscv_kvm_init);
+
+static void __exit riscv_kvm_exit(void)
+{
+ kvm_riscv_aia_exit();
+
+ kvm_exit();
+}
+module_exit(riscv_kvm_exit);