[PATCH v1 01/14] xen/riscv: implement get_s_time()

[Oleksii Kurochko]

Also tick_to_ns() is implemeted as it is used in get_s_time().

Signed-off-by: Oleksii Kurochko <oleksii.kuroc...@gmail.com>
---
 xen/arch/riscv/include/asm/time.h | 6 ++++++
 xen/arch/riscv/stubs.c            | 5 -----
 xen/arch/riscv/time.c             | 7 +++++++
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/xen/arch/riscv/include/asm/time.h 
b/xen/arch/riscv/include/asm/time.h
index e8d9ffec57..0f6aa99ab1 100644
--- a/xen/arch/riscv/include/asm/time.h
+++ b/xen/arch/riscv/include/asm/time.h
@@ -3,6 +3,7 @@
 #define ASM__RISCV__TIME_H
 
 #include <xen/bug.h>
+#include <xen/lib.h>
 #include <xen/types.h>
 #include <asm/csr.h>
 
@@ -23,6 +24,11 @@ static inline cycles_t get_cycles(void)
     return csr_read(CSR_TIME);
 }
 
+static inline s_time_t ticks_to_ns(uint64_t ticks)
+{
+    return muldiv64(ticks, SECONDS(1), 1000 * cpu_khz);
+}
+
 void preinit_xen_time(void);
 
 #endif /* ASM__RISCV__TIME_H */
diff --git a/xen/arch/riscv/stubs.c b/xen/arch/riscv/stubs.c
index a1d64534cd..83416d3350 100644
--- a/xen/arch/riscv/stubs.c
+++ b/xen/arch/riscv/stubs.c
@@ -27,11 +27,6 @@ nodemask_t __read_mostly node_online_map = { { [0] = 1UL } };
 
 /* time.c */
 
-s_time_t get_s_time(void)
-{
-    BUG_ON("unimplemented");
-}
-
 int reprogram_timer(s_time_t timeout)
 {
     BUG_ON("unimplemented");
diff --git a/xen/arch/riscv/time.c b/xen/arch/riscv/time.c
index 905bb13eb4..81e06781f8 100644
--- a/xen/arch/riscv/time.c
+++ b/xen/arch/riscv/time.c
@@ -4,10 +4,17 @@
 #include <xen/init.h>
 #include <xen/lib.h>
 #include <xen/sections.h>
+#include <xen/types.h>
 
 unsigned long __ro_after_init cpu_khz; /* CPU clock frequency in kHz. */
 uint64_t __ro_after_init boot_clock_cycles;
 
+s_time_t get_s_time(void)
+{
+    uint64_t ticks = get_cycles() - boot_clock_cycles;
+    return ticks_to_ns(ticks);
+}
+
 /* Set up the timer on the boot CPU (early init function) */
 static void __init preinit_dt_xen_time(void)
 {
-- 
2.49.0