hw/arm/stm32f205: Wire up sysclk and refclk

Wire up the sysclk and refclk for the stm32f205 SoC.  This SoC always
runs the systick refclk at 1/8 the frequency of the main CPU clock,
so the board code only needs to provide a single sysclk clock.

Because there is only one board using this SoC, we convert the SoC
and the board together, rather than splitting it into "add clock to
SoC; connect clock in board; add error check in SoC code that clock
is wired up".

When the systick device starts honouring its clock inputs, this will
fix an emulation inaccuracy in the netduino2 board where the systick
reference clock was running at 1MHz rather than 15MHz.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Alexandre Iooss <erdnaxe@crans.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Message-id: 20210812093356.1946-13-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2021-08-12 10:33:43 +01:00
parent b5ff0c6183
commit 68ba05fba4
3 changed files with 41 additions and 5 deletions

View file

@ -26,6 +26,7 @@
#include "qapi/error.h"
#include "hw/boards.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-clock.h"
#include "qemu/error-report.h"
#include "hw/arm/stm32f205_soc.h"
#include "hw/arm/boot.h"
@ -36,16 +37,17 @@
static void netduino2_init(MachineState *machine)
{
DeviceState *dev;
Clock *sysclk;
/*
* TODO: ideally we would model the SoC RCC and let it handle
* system_clock_scale, including its ability to define different
* possible SYSCLK sources.
*/
system_clock_scale = NANOSECONDS_PER_SECOND / SYSCLK_FRQ;
/* This clock doesn't need migration because it is fixed-frequency */
sysclk = clock_new(OBJECT(machine), "SYSCLK");
clock_set_hz(sysclk, SYSCLK_FRQ);
dev = qdev_new(TYPE_STM32F205_SOC);
qdev_prop_set_string(dev, "cpu-type", ARM_CPU_TYPE_NAME("cortex-m3"));
qdev_connect_clock_in(dev, "sysclk", sysclk);
sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
armv7m_load_kernel(ARM_CPU(first_cpu), machine->kernel_filename,