@samitouri / QOSamiQemu / commits / 22947b2e95

hvf: arm: physical timer emulation

Enable this through leveraging TCG's physical timer emulation. This allows nested virtualisation to work with a kernel-irqchip=off + GICv2. Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr> Message-id: 20260429190532.26538-14-mohamed@unpredictable.fr Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Mohamed Mediouni committed May 5, 2026 at 09:25 UTC 22947b2e95f37573b50db363bafb6ae4a6fcc2f2
1 file changed +19 -9
target/arm/hvf/hvf.c
+19 -9
@@ -189,7 +189,9 @@ void hvf_arm_init_debug(void)
189 #define SYSREG_OSDLR_EL1 SYSREG(2, 0, 1, 3, 4)
190 #define SYSREG_LORC_EL1 SYSREG(3, 0, 10, 4, 3)
191 #define SYSREG_CNTPCT_EL0 SYSREG(3, 3, 14, 0, 1)
192 +#define SYSREG_CNTP_TVAL_EL0 SYSREG(3, 3, 14, 2, 0)
193 #define SYSREG_CNTP_CTL_EL0 SYSREG(3, 3, 14, 2, 1)
194 +#define SYSREG_CNTP_CVAL_EL0 SYSREG(3, 3, 14, 2, 2)
195 #define SYSREG_PMCR_EL0 SYSREG(3, 3, 9, 12, 0)
196 #define SYSREG_PMUSERENR_EL0 SYSREG(3, 3, 9, 14, 0)
197 #define SYSREG_PMCNTENSET_EL0 SYSREG(3, 3, 9, 12, 1)
@@ -1728,9 +1730,15 @@ static int hvf_sysreg_read(CPUState *cpu, uint32_t reg, uint64_t *val)
1730
1731 switch (reg) {
1732 case SYSREG_CNTPCT_EL0:
1731 - *val = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) /
1732 - gt_cntfrq_period_ns(arm_cpu);
1733 - return 0;
1733 + case SYSREG_CNTP_CTL_EL0:
1734 + case SYSREG_CNTP_CVAL_EL0:
1735 + case SYSREG_CNTP_TVAL_EL0:
1736 + assert(!hvf_irqchip_in_kernel());
1737 + /* Call the TCG sysreg handler. */
1738 + if (hvf_sysreg_read_cp(cpu, "PTimer", reg, val)) {
1739 + return 0;
1740 + }
1741 + break;
1742 case SYSREG_OSLSR_EL1:
1743 *val = env->cp15.oslsr_el1;
1744 return 0;
@@ -2024,12 +2032,14 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val)
2032 env->cp15.oslsr_el1 = val & 1;
2033 return 0;
2034 case SYSREG_CNTP_CTL_EL0:
2027 - /*
2028 - * Guests should not rely on the physical counter, but macOS emits
2029 - * disable writes to it. Let it do so, but ignore the requests.
2030 - */
2031 - qemu_log_mask(LOG_UNIMP, "Unsupported write to CNTP_CTL_EL0\n");
2032 - return 0;
2035 + case SYSREG_CNTP_CVAL_EL0:
2036 + case SYSREG_CNTP_TVAL_EL0:
2037 + assert(!hvf_irqchip_in_kernel());
2038 + /* Call the TCG sysreg handler. */
2039 + if (hvf_sysreg_write_cp(cpu, "PTimer", reg, val)) {
2040 + return 0;
2041 + }
2042 + break;
2043 case SYSREG_OSDLR_EL1:
2044 /* Dummy register */
2045 return 0;