[PATCH v2 03/29] LoongArch: KVM: Implement kvm hardware enable, disable interface

[Tianrui Zhao]

Implement kvm hardware enable, disable interface, setting
the guest config register to enable virtualization features
when called the interface.

Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
---
 arch/loongarch/kvm/main.c | 71 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
index d7969d02a..6afd97823 100644
--- a/arch/loongarch/kvm/main.c
+++ b/arch/loongarch/kvm/main.c
@@ -11,6 +11,77 @@
 
 static struct kvm_context __percpu *vmcs;
 
+void kvm_init_vmcs(struct kvm *kvm)
+{
+	kvm->arch.vmcs = vmcs;
+}
+
+long kvm_arch_dev_ioctl(struct file *filp,
+			unsigned int ioctl, unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_check_processor_compat(void *opaque)
+{
+	return 0;
+}
+
+int kvm_arch_hardware_setup(void *opaque)
+{
+	return 0;
+}
+
+int kvm_arch_hardware_enable(void)
+{
+	unsigned long gcfg = 0;
+
+	/* First init gtlbc, gcfg, gstat, gintc. All guest use the same config */
+	clear_csr_gtlbc(CSR_GTLBC_USETGID | CSR_GTLBC_TOTI);
+	write_csr_gcfg(0);
+	write_csr_gstat(0);
+	write_csr_gintc(0);
+
+	/*
+	 * Enable virtualization features granting guest direct control of
+	 * certain features:
+	 * GCI=2:       Trap on init or unimplement cache instruction.
+	 * TORU=0:      Trap on Root Unimplement.
+	 * CACTRL=1:    Root control cache.
+	 * TOP=0:       Trap on Previlege.
+	 * TOE=0:       Trap on Exception.
+	 * TIT=0:       Trap on Timer.
+	 */
+	if (cpu_has_gcip_all)
+		gcfg |= CSR_GCFG_GCI_SECURE;
+	if (cpu_has_matc_root)
+		gcfg |= CSR_GCFG_MATC_ROOT;
+
+	gcfg |= CSR_GCFG_TIT;
+	write_csr_gcfg(gcfg);
+
+	kvm_flush_tlb_all();
+
+	/* Enable using TGID  */
+	set_csr_gtlbc(CSR_GTLBC_USETGID);
+	kvm_debug("gtlbc:%llx gintc:%llx gstat:%llx gcfg:%llx",
+			read_csr_gtlbc(), read_csr_gintc(),
+			read_csr_gstat(), read_csr_gcfg());
+
+	return 0;
+}
+
+void kvm_arch_hardware_disable(void)
+{
+	clear_csr_gtlbc(CSR_GTLBC_USETGID | CSR_GTLBC_TOTI);
+	write_csr_gcfg(0);
+	write_csr_gstat(0);
+	write_csr_gintc(0);
+
+	/* Flush any remaining guest TLB entries */
+	kvm_flush_tlb_all();
+}
+
 int kvm_arch_init(void *opaque)
 {
 	struct kvm_context *context;
-- 
2.31.1