Commit Graph

5 Commits

Author SHA1 Message Date
Peter Maydell
b7cd9c1e84 clock: Define and use new clock_display_freq()
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>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201215150929.30311-5-peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2021-01-04 23:24:44 +01:00
Luc Michel
a6414d3b59 hw/core/clock: trace clock values in Hz instead of ns
The nanosecond unit greatly limits the dynamic range we can display in
clock value traces, for values in the order of 1GHz and more. The
internal representation can go way beyond this value and it is quite
common for today's clocks to be within those ranges.

For example, a frequency between 500MHz+ and 1GHz will be displayed as
1ns. Beyond 1GHz, it will show up as 0ns.

Replace nanosecond periods traces with frequencies in the Hz unit
to have more dynamic range in the trace output.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Signed-off-by: Luc Michel <luc@lmichel.fr>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-10-27 11:10:44 +00:00
Luc Michel
5ebc664800 hw/core/clock: Add the clock_new helper function
This function creates a clock and parents it to another object with a
given name. It calls clock_setup_canonical_path before returning the
new clock.

This function is useful to create clocks in devices when one doesn't
want to expose it at the qdev level (as an input or an output).

Suggested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Luc Michel <luc@lmichel.fr>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201010135759.437903-4-luc@lmichel.fr>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2020-10-16 18:58:10 +02:00
Philippe Mathieu-Daudé
15aa2876d9 hw/clock: Let clock_set() return boolean value
Let clock_set() return a boolean value whether the clock
has been updated or not.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200806123858.30058-3-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-08-28 10:02:44 +01:00
Peter Maydell
4cba075efe hw/core/clock: introduce clock object
This object may be used to represent a clock inside a clock tree.

A clock may be connected to another clock so that it receives update,
through a callback, whenever the source/parent clock is updated.

Although only the root clock of a clock tree controls the values
(represented as periods) of all clocks in tree, each clock holds
a local state containing the current value so that it can be fetched
independently. It will allows us to fullfill migration requirements
by migrating each clock independently of others.

This is based on the original work of Frederic Konrad.

Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20200406135251.157596-2-damien.hedde@greensocs.com
[PMM: Use uint64_t rather than unsigned long long in trace events;
 the dtrace backend can't handle the latter]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-04-30 11:52:28 +01:00