On 7/11/25 11:23, Luc Michel wrote:
Add the RISCVCPUTimeSrcIf QOM interface to the RISC-V target. This
interface aims at replacing the existing env->rdtime_fn callback in the
RISC-V CPU env. It allows to query the current number of ticks, and the
tick frequency.
Signed-off-by: Luc Michel <[email protected]>
---
target/riscv/cpu-qom.h | 34 ++++++++++++++++++++++++++++++++++
target/riscv/time_helper.h | 16 ++++++++++++++++
target/riscv/time_helper.c | 13 +++++++++++++
3 files changed, 63 insertions(+)
diff --git a/target/riscv/cpu-qom.h b/target/riscv/cpu-qom.h
index 75f4e434085..e5bc23b2ef5 100644
--- a/target/riscv/cpu-qom.h
+++ b/target/riscv/cpu-qom.h
@@ -58,6 +58,40 @@
#define TYPE_RISCV_CPU_XIANGSHAN_KMH
RISCV_CPU_TYPE_NAME("xiangshan-kunminghu")
#define TYPE_RISCV_CPU_HOST RISCV_CPU_TYPE_NAME("host")
OBJECT_DECLARE_CPU_TYPE(RISCVCPU, RISCVCPUClass, RISCV_CPU)
+#define TYPE_RISCV_CPU_TIME_SRC_IF "riscv-cpu-time-src-if"
+
+typedef struct RISCVCPUTimeSrcIfClass RISCVCPUTimeSrcIfClass;
+DECLARE_CLASS_CHECKERS(RISCVCPUTimeSrcIfClass, RISCV_CPU_TIME_SRC_IF,
+ TYPE_RISCV_CPU_TIME_SRC_IF)
+#define RISCV_CPU_TIME_SRC_IF(obj) \
+ INTERFACE_CHECK(RISCVCPUTimeSrcIf, (obj), TYPE_RISCV_CPU_TIME_SRC_IF)
+
+typedef struct RISCVCPUTimeSrcIf RISCVCPUTimeSrcIf;
+
+/**
+ * RISCVCPUTimeSrcIf interface
+ *
+ * This interface is used by CPUs implementing the sstc extension. When the CPU
+ * implements this extension, it must have a time source to implement the sstc
+ * timers. Devices implementing this interface provide a monotonic tick counter
+ * and the associated tick frequency so that the CPU code can compute timer
+ * deadlines.
+ */
+struct RISCVCPUTimeSrcIfClass {
+ InterfaceClass parent_class;
+
+ /**
+ * get_ticks: get the current value of the free running counter associated
+ * with this time source.
+ */
+ uint64_t (*get_ticks)(RISCVCPUTimeSrcIf *);
+
+ /**
+ * get_tick_freq: get the tick frequency of this time source.
+ */
+ uint32_t (*get_tick_freq)(RISCVCPUTimeSrcIf *);
+};
Thanks for the documentation :)
diff --git a/target/riscv/time_helper.h b/target/riscv/time_helper.h
index af1f634f890..b51fdd96570 100644
--- a/target/riscv/time_helper.h
+++ b/target/riscv/time_helper.h
@@ -26,6 +26,22 @@ void riscv_timer_write_timecmp(CPURISCVState *env, QEMUTimer
*timer,
uint64_t timecmp, uint64_t delta,
uint32_t timer_irq);
void riscv_timer_stce_changed(CPURISCVState *env, bool is_m_mode, bool
enable);
void riscv_timer_init(RISCVCPU *cpu);
+static inline uint64_t riscv_cpu_time_src_get_ticks(RISCVCPUTimeSrcIf *src)
+{
+ RISCVCPUTimeSrcIfClass *rctsc = RISCV_CPU_TIME_SRC_IF_GET_CLASS(src);
+
+ g_assert(rctsc->get_ticks != NULL);
+ return rctsc->get_ticks(src);
+}
+
+static inline uint32_t riscv_cpu_time_src_get_tick_freq(RISCVCPUTimeSrcIf *src)
+{
+ RISCVCPUTimeSrcIfClass *rctsc = RISCV_CPU_TIME_SRC_IF_GET_CLASS(src);
+
+ g_assert(rctsc->get_tick_freq != NULL);
+ return rctsc->get_tick_freq(src);
+}
Why inlining these functions? Otherwise,
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
