KVM: arm64: Enable the EL1 physical timer for AArch32 guests

Some 32bits guest OS can use the CNTP timer, however KVM does not
handle the accesses, injecting a fault instead.

Use the proper handlers to emulate the EL1 Physical Timer (CNTP)
register accesses of AArch32 guests.
Signed-off-by: NJérémy Fanguède <j.fanguede@virtualopensystems.com>
Signed-off-by: NAlvise Rigo <a.rigo@virtualopensystems.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

arch/arm64/kvm/sys_regs.c

@@ -1565,6 +1565,11 @@ static const struct sys_reg_desc cp15_regs[] = {
 
 	{ Op1( 0), CRn(13), CRm( 0), Op2( 1), access_vm_reg, NULL, c13_CID },
 
+	/* CNTP_TVAL */
+	{ Op1( 0), CRn(14), CRm( 2), Op2( 0), access_cntp_tval },
+	/* CNTP_CTL */
+	{ Op1( 0), CRn(14), CRm( 2), Op2( 1), access_cntp_ctl },
+
 	/* PMEVCNTRn */
 	PMU_PMEVCNTR(0),
 	PMU_PMEVCNTR(1),
@@ -1638,6 +1643,7 @@ static const struct sys_reg_desc cp15_64_regs[] = {
 	{ Op1( 0), CRn( 0), CRm( 9), Op2( 0), access_pmu_evcntr },
 	{ Op1( 0), CRn( 0), CRm(12), Op2( 0), access_gic_sgi },
 	{ Op1( 1), CRn( 0), CRm( 2), Op2( 0), access_vm_reg, NULL, c2_TTBR1 },
+	{ Op1( 2), CRn( 0), CRm(14), Op2( 0), access_cntp_cval },
 };
 
 /* Target specific emulation tables */