LoongArch: KVM: Set reserved bit as zero about cpucfg

Commit Message

Bibo Mao March 5, 2024, 11:33 a.m. UTC

Supported cpucfg information comes from function _kvm_get_cpucfg_mask().
It should be zero if it is reserved by HW or if it is not supported
by KVM.

Also LoongArch software page table walk feature defined in CPUCFG2_PTW
is supported by KVM, it should be enabled by default.

Signed-off-by: Bibo Mao <[e-mail]>
---
 arch/loongarch/kvm/vcpu.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

Patch

diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index 36106922b5d7..fc25c406021c 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -304,11 +304,15 @@  static int _kvm_get_cpucfg_mask(int id, u64 *v)
 		return -EINVAL;
 
 	switch (id) {
-	case 2:
+	case LOONGARCH_CPUCFG1:
+		/* CPUCFG1_MSGINT is not supported by KVM */
+		*v = GENMASK(25, 0);
+		return 0;
+	case LOONGARCH_CPUCFG2:
 		/* CPUCFG2 features unconditionally supported by KVM */
 		*v = CPUCFG2_FP     | CPUCFG2_FPSP  | CPUCFG2_FPDP     |
 		     CPUCFG2_FPVERS | CPUCFG2_LLFTP | CPUCFG2_LLFTPREV |
-		     CPUCFG2_LAM;
+		     CPUCFG2_LSPW | CPUCFG2_LAM;
 		/*
 		 * For the ISA extensions listed below, if one is supported
 		 * by the host, then it is also supported by KVM.
@@ -318,6 +322,21 @@  static int _kvm_get_cpucfg_mask(int id, u64 *v)
 		if (cpu_has_lasx)
 			*v |= CPUCFG2_LASX;
 
+		return 0;
+	case LOONGARCH_CPUCFG3:
+		*v = GENMASK(16, 0);
+		return 0;
+	case LOONGARCH_CPUCFG6:
+		/* PMU is not supported by KVM now */
+	case LOONGARCH_CPUCFG6 + 1 ... LOONGARCH_CPUCFG16 - 1:
+		/* Not used by HW now, need be zero */
+		*v = 0;
+		return 0;
+	case LOONGARCH_CPUCFG16:
+		*v = GENMASK(16, 0);
+		return 0;
+	case LOONGARCH_CPUCFG17 ... LOONGARCH_CPUCFG20:
+		*v = GENMASK(30, 0);
 		return 0;
 	default:
 		/*
@@ -344,7 +363,7 @@  static int kvm_check_cpucfg(int id, u64 val)
 		return -EINVAL;
 
 	switch (id) {
-	case 2:
+	case LOONGARCH_CPUCFG2:
 		if (!(val & CPUCFG2_LLFTP))
 			/* Guests must have a constant timer */
 			return -EINVAL;