It's common to want to print a human-readable indication of a clock's
frequency. Provide a utility function in the clock API to return a
string which is a displayable representation of the frequency,
and use it in qdev-monitor.c.
Before:
(qemu) info qtree
[...]
dev: xilinx,zynq_slcr, id ""
clock-in "ps_clk" freq_hz=3.333333e+07
mmio 00000000f8000000/0000000000001000
After:
dev: xilinx,zynq_slcr, id ""
clock-in "ps_clk" freq_hz=33.3 MHz
mmio 00000000f8000000/0000000000001000
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
This is based on Philippe's patch
"qdev-monitor: Display frequencies scaled to SI unit"
but I have abstracted out the "prettified string" into the clock API.
---
docs/devel/clocks.rst | 5 +++++
include/hw/clock.h | 12 ++++++++++++
hw/core/clock.c | 6 ++++++
softmmu/qdev-monitor.c | 6 +++---
4 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst
index 9a93d1361b4..cf8067542a1 100644
--- a/docs/devel/clocks.rst
+++ b/docs/devel/clocks.rst
@@ -267,6 +267,11 @@ Here is an example:
clock_get(dev->my_clk_input));
}
+If you are only interested in the frequency for displaying it to
+humans (for instance in debugging), use ``clock_display_freq()``,
+which returns a prettified string-representation, e.g. "33.3 MHz".
+The caller must free the string with g_free() after use.
+
Calculating expiry deadlines
----------------------------
diff --git a/include/hw/clock.h b/include/hw/clock.h
index 9c0b1eb4c3f..7bc9afb0800 100644
--- a/include/hw/clock.h
+++ b/include/hw/clock.h
@@ -252,4 +252,16 @@ static inline bool clock_is_enabled(const Clock *clk)
return clock_get(clk) != 0;
}
+/**
+ * clock_display_freq: return human-readable representation of clock frequency
+ * @clk: clock
+ *
+ * Return a string which has a human-readable representation of the
+ * clock's frequency, e.g. "33.3 MHz". This is intended for debug
+ * and display purposes.
+ *
+ * The caller is responsible for freeing the string with g_free().
+ */
+char *clock_display_freq(Clock *clk);
+
#endif /* QEMU_HW_CLOCK_H */
diff --git a/hw/core/clock.c b/hw/core/clock.c
index 8c6af223e7c..76b5f468b6e 100644
--- a/hw/core/clock.c
+++ b/hw/core/clock.c
@@ -12,6 +12,7 @@
*/
#include "qemu/osdep.h"
+#include "qemu/cutils.h"
#include "hw/clock.h"
#include "trace.h"
@@ -111,6 +112,11 @@ static void clock_disconnect(Clock *clk)
QLIST_REMOVE(clk, sibling);
}
+char *clock_display_freq(Clock *clk)
+{
+ return freq_to_str(clock_get_hz(clk));
+}
+
static void clock_initfn(Object *obj)
{
Clock *clk = CLOCK(obj);
diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
index bf79d0bbcd9..6263d600026 100644
--- a/softmmu/qdev-monitor.c
+++ b/softmmu/qdev-monitor.c
@@ -747,11 +747,11 @@ static void qdev_print(Monitor *mon, DeviceState *dev, int indent)
}
}
QLIST_FOREACH(ncl, &dev->clocks, node) {
- qdev_printf("clock-%s%s \"%s\" freq_hz=%e\n",
+ g_autofree char *freq_str = clock_display_freq(ncl->clock);
+ qdev_printf("clock-%s%s \"%s\" freq_hz=%s\n",
ncl->output ? "out" : "in",
ncl->alias ? " (alias)" : "",
- ncl->name,
- CLOCK_PERIOD_TO_HZ(1.0 * clock_get(ncl->clock)));
+ ncl->name, freq_str);
}
class = object_get_class(OBJECT(dev));
do {
--
2.20.1
On 12/8/20 12:15 PM, Peter Maydell wrote: > It's common to want to print a human-readable indication of a clock's > frequency. Provide a utility function in the clock API to return a > string which is a displayable representation of the frequency, > and use it in qdev-monitor.c. > > Before: > > (qemu) info qtree > [...] > dev: xilinx,zynq_slcr, id "" > clock-in "ps_clk" freq_hz=3.333333e+07 > mmio 00000000f8000000/0000000000001000 > > After: > > dev: xilinx,zynq_slcr, id "" > clock-in "ps_clk" freq_hz=33.3 MHz > mmio 00000000f8000000/0000000000001000 > > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > This is based on Philippe's patch > "qdev-monitor: Display frequencies scaled to SI unit" > but I have abstracted out the "prettified string" into the clock API. > --- Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
On 12/8/20 7:15 PM, Peter Maydell wrote:
> It's common to want to print a human-readable indication of a clock's
> frequency. Provide a utility function in the clock API to return a
> string which is a displayable representation of the frequency,
> and use it in qdev-monitor.c.
>
> Before:
>
> (qemu) info qtree
> [...]
> dev: xilinx,zynq_slcr, id ""
> clock-in "ps_clk" freq_hz=3.333333e+07
> mmio 00000000f8000000/0000000000001000
>
> After:
>
> dev: xilinx,zynq_slcr, id ""
> clock-in "ps_clk" freq_hz=33.3 MHz
> mmio 00000000f8000000/0000000000001000
>
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
> ---
> This is based on Philippe's patch
> "qdev-monitor: Display frequencies scaled to SI unit"
> but I have abstracted out the "prettified string" into the clock API.
> ---
> docs/devel/clocks.rst | 5 +++++
> include/hw/clock.h | 12 ++++++++++++
> hw/core/clock.c | 6 ++++++
> softmmu/qdev-monitor.c | 6 +++---
> 4 files changed, 26 insertions(+), 3 deletions(-)
>
> diff --git a/docs/devel/clocks.rst b/docs/devel/clocks.rst
> index 9a93d1361b4..cf8067542a1 100644
> --- a/docs/devel/clocks.rst
> +++ b/docs/devel/clocks.rst
> @@ -267,6 +267,11 @@ Here is an example:
> clock_get(dev->my_clk_input));
> }
>
> +If you are only interested in the frequency for displaying it to
> +humans (for instance in debugging), use ``clock_display_freq()``,
> +which returns a prettified string-representation, e.g. "33.3 MHz".
> +The caller must free the string with g_free() after use.
> +
> Calculating expiry deadlines
> ----------------------------
>
> diff --git a/include/hw/clock.h b/include/hw/clock.h
> index 9c0b1eb4c3f..7bc9afb0800 100644
> --- a/include/hw/clock.h
> +++ b/include/hw/clock.h
> @@ -252,4 +252,16 @@ static inline bool clock_is_enabled(const Clock *clk)
> return clock_get(clk) != 0;
> }
>
> +/**
> + * clock_display_freq: return human-readable representation of clock frequency
> + * @clk: clock
> + *
> + * Return a string which has a human-readable representation of the
> + * clock's frequency, e.g. "33.3 MHz". This is intended for debug
> + * and display purposes.
> + *
> + * The caller is responsible for freeing the string with g_free().
> + */
> +char *clock_display_freq(Clock *clk);
> +
> #endif /* QEMU_HW_CLOCK_H */
> diff --git a/hw/core/clock.c b/hw/core/clock.c
> index 8c6af223e7c..76b5f468b6e 100644
> --- a/hw/core/clock.c
> +++ b/hw/core/clock.c
> @@ -12,6 +12,7 @@
> */
>
> #include "qemu/osdep.h"
> +#include "qemu/cutils.h"
> #include "hw/clock.h"
> #include "trace.h"
>
> @@ -111,6 +112,11 @@ static void clock_disconnect(Clock *clk)
> QLIST_REMOVE(clk, sibling);
> }
>
> +char *clock_display_freq(Clock *clk)
> +{
> + return freq_to_str(clock_get_hz(clk));
> +}
> +
> static void clock_initfn(Object *obj)
> {
> Clock *clk = CLOCK(obj);
> diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
> index bf79d0bbcd9..6263d600026 100644
> --- a/softmmu/qdev-monitor.c
> +++ b/softmmu/qdev-monitor.c
> @@ -747,11 +747,11 @@ static void qdev_print(Monitor *mon, DeviceState *dev, int indent)
> }
> }
> QLIST_FOREACH(ncl, &dev->clocks, node) {
> - qdev_printf("clock-%s%s \"%s\" freq_hz=%e\n",
> + g_autofree char *freq_str = clock_display_freq(ncl->clock);
> + qdev_printf("clock-%s%s \"%s\" freq_hz=%s\n",
> ncl->output ? "out" : "in",
> ncl->alias ? " (alias)" : "",
> - ncl->name,
> - CLOCK_PERIOD_TO_HZ(1.0 * clock_get(ncl->clock)));
> + ncl->name, freq_str);
> }
> class = object_get_class(OBJECT(dev));
> do {
>
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