Linux kernel from version 3.4 requires CM_REFCNT register for sched timer for Integrator/CP board (integrator_defconfig).
See http://infocenter.arm.com/help/topic/com.arm.doc.dui0138e/ch04s06s11.html Signed-off-by: Jan Petrous <jan.petr...@tieto.com> --- hw/arm/integratorcp.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/hw/arm/integratorcp.c b/hw/arm/integratorcp.c index c44b2a4..f419764 100644 --- a/hw/arm/integratorcp.c +++ b/hw/arm/integratorcp.c @@ -83,8 +83,11 @@ static uint64_t integratorcm_read(void *opaque, hwaddr offset, case 9: /* CM_INIT */ return s->cm_init; case 10: /* CM_REFCT */ - /* ??? High frequency timer. */ - hw_error("integratorcm_read: CM_REFCT"); + /* This register, CM_REFCNT, provides a 32-bit count value. + * The count increments at the fixed reference clock frequency of 24MHz + * and can be used as a real-time counter. + */ + return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), 24, 1000); case 12: /* CM_FLAGS */ return s->cm_flags; case 14: /* CM_NVFLAGS */ -- 1.7.11.3
From a4f7f6220df71a7c7540a6722cc5f96c7d061e28 Mon Sep 17 00:00:00 2001 From: Jan Petrous <jan.petr...@tieto.com> Date: Tue, 5 Nov 2013 12:13:57 +0100 Subject: [PATCH] integrator/cp: add support for REFCNT register Linux kernel from version 3.4 requires CM_REFCNT register for sched timer for Integrator/CP board (integrator_defconfig). See http://infocenter.arm.com/help/topic/com.arm.doc.dui0138e/ch04s06s11.html Signed-off-by: Jan Petrous <jan.petr...@tieto.com> --- hw/arm/integratorcp.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/hw/arm/integratorcp.c b/hw/arm/integratorcp.c index c44b2a4..f419764 100644 --- a/hw/arm/integratorcp.c +++ b/hw/arm/integratorcp.c @@ -83,8 +83,11 @@ static uint64_t integratorcm_read(void *opaque, hwaddr offset, case 9: /* CM_INIT */ return s->cm_init; case 10: /* CM_REFCT */ - /* ??? High frequency timer. */ - hw_error("integratorcm_read: CM_REFCT"); + /* This register, CM_REFCNT, provides a 32-bit count value. + * The count increments at the fixed reference clock frequency of 24MHz + * and can be used as a real-time counter. + */ + return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), 24, 1000); case 12: /* CM_FLAGS */ return s->cm_flags; case 14: /* CM_NVFLAGS */ -- 1.7.11.3
