Re: [PATCH v4 2/2] hw/arm: Add minimal support for the B-L475E-IOT01A board

[Philippe Mathieu-Daudé]

On 21/12/23 22:32, Inès Varhol wrote:
> This commit adds a new B-L475E-IOT01A board using the STM32L475VG SoC
> as well as a dedicated documentation file.
> The implementation is derived from the Netduino Plus 2 machine.
> There are no peripherals implemented yet, only memory regions.
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>
> Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
> Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
> ---
>   MAINTAINERS                             |  7 +++
>   configs/devices/arm-softmmu/default.mak |  1 +
>   docs/system/arm/b-l475e-iot01a.rst      | 46 ++++++++++++++++
>   docs/system/arm/stm32.rst               |  6 ++-
>   docs/system/target-arm.rst              |  1 +
>   hw/arm/Kconfig                          |  6 +++
>   hw/arm/b-l475e-iot01a.c                 | 70 +++++++++++++++++++++++++
>   hw/arm/meson.build                      |  1 +
>   8 files changed, 136 insertions(+), 2 deletions(-)
>   create mode 100644 docs/system/arm/b-l475e-iot01a.rst
>   create mode 100644 hw/arm/b-l475e-iot01a.c


> diff --git a/hw/arm/b-l475e-iot01a.c b/hw/arm/b-l475e-iot01a.c
> new file mode 100644
> index 0000000000..c3790e3dc8
> --- /dev/null
> +++ b/hw/arm/b-l475e-iot01a.c
> @@ -0,0 +1,70 @@
> +/*
> + * B-L475E-IOT01A Discovery Kit machine
> + * (B-L475E-IOT01A IoT Node)
> + *
> + * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
> + * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + * This work is heavily inspired by the netduinoplus2 by Alistair Francis.
> + * Original code is licensed under the MIT License:
> + *
> + * Copyright (c) 2014 Alistair Francis <alistair@alistair23.me>
> + */
> +
> +/*
> + * The reference used is the STMicroElectronics UM2153 User manual
> + * Discovery kit for IoT node, multi-channel communication with STM32L4.
> + * https://www.st.com/en/evaluation-tools/b-l475e-iot01a.html#documentation
> + */
> +
> +#include "qemu/osdep.h"
> +#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/stm32l4x5_soc.h"
> +#include "hw/arm/boot.h"
> +
> +/* Main SYSCLK frequency in Hz (80MHz) */
> +#define SYSCLK_FRQ 80000000ULL
> +
> +static void b_l475e_iot01a_init(MachineState *machine)
> +{
> +    const Stm32l4x5SocClass *sc;
> +    DeviceState *dev;
> +    Clock *sysclk;
> +
> +    /* 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_STM32L4X5XG_SOC);

Missing machine parentship relation.

> +    sc = STM32L4X5_SOC_GET_CLASS(dev);
> +    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,
> +                       0, sc->flash_size);
> +}

Using:

-- >8 --
diff --git a/hw/arm/b-l475e-iot01a.c b/hw/arm/b-l475e-iot01a.c
index c3790e3dc8..85b8cdcd57 100644
--- a/hw/arm/b-l475e-iot01a.c
+++ b/hw/arm/b-l475e-iot01a.c
@@ -45,10 +45,11 @@ static void b_l475e_iot01a_init(MachineState *machine)
     clock_set_hz(sysclk, SYSCLK_FRQ);

     dev = qdev_new(TYPE_STM32L4X5XG_SOC);
-    sc = STM32L4X5_SOC_GET_CLASS(dev);
+    object_property_add_child(OBJECT(machine), "soc", OBJECT(dev));
     qdev_connect_clock_in(dev, "sysclk", sysclk);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);

+    sc = STM32L4X5_SOC_GET_CLASS(dev);
     armv7m_load_kernel(ARM_CPU(first_cpu),
                        machine->kernel_filename,
                        0, sc->flash_size);
---

we get:

(qemu) info qom-tree
/machine (b-l475e-iot01a-machine)
  /SYSCLK (clock)
  /peripheral (container)
  /peripheral-anon (container)
  /soc (stm32l4x5xg-soc)
    /SRAM1[0] (memory-region)
    /SRAM2[0] (memory-region)
    /armv7m (armv7m)
      /armv7m-container[0] (memory-region)
      /bitband[0] (ARM-bitband-memory)
        /bitband[0] (memory-region)
      /bitband[1] (ARM-bitband-memory)
        /bitband[0] (memory-region)
      /cpu (cortex-m4-arm-cpu)
        /unnamed-gpio-in[0] (irq)
        /unnamed-gpio-in[1] (irq)
        /unnamed-gpio-in[2] (irq)
        /unnamed-gpio-in[3] (irq)
      /cpuclk (clock)
      /nvic (armv7m_nvic)
        /NMI[0] (irq)
        ...