Re: [PATCH v4 20/45] Implement BCM2838 thermal sensor

[Peter Maydell <peter.maydell@linaro.org>]

On Fri, 8 Dec 2023 at 02:33, Sergey Kambalin <serg.oker@gmail.com> wrote:
>
> Signed-off-by: Sergey Kambalin <sergey.kambalin@auriga.com>
> ---
>  hw/arm/bcm2838_peripherals.c         | 27 ++++++--
>  hw/arm/raspi4b.c                     |  1 -
>  hw/misc/bcm2838_thermal.c            | 98 ++++++++++++++++++++++++++++
>  hw/misc/meson.build                  |  3 +-
>  include/hw/arm/bcm2838_peripherals.h |  2 +
>  include/hw/misc/bcm2838_thermal.h    | 24 +++++++
>  6 files changed, 147 insertions(+), 8 deletions(-)
>  create mode 100644 hw/misc/bcm2838_thermal.c
>  create mode 100644 include/hw/misc/bcm2838_thermal.h
>
> diff --git a/hw/arm/bcm2838_peripherals.c b/hw/arm/bcm2838_peripherals.c
> index 7c489c8e8a..e9c6d47ba6 100644
> --- a/hw/arm/bcm2838_peripherals.c
> +++ b/hw/arm/bcm2838_peripherals.c
> @@ -37,6 +37,9 @@ static void bcm2838_peripherals_init(Object *obj)
>      /* Random Number Generator */
>      object_initialize_child(obj, "rng200", &s->rng200, TYPE_BCM2838_RNG200);
>
> +    /* Thermal */
> +    object_initialize_child(obj, "thermal", &s->thermal, TYPE_BCM2838_THERMAL);
> +
>      /* PCIe Host Bridge */
>      object_initialize_child(obj, "pcie-host", &s->pcie_host,
>                              TYPE_BCM2838_PCIE_HOST);
> @@ -75,6 +78,9 @@ static void bcm2838_peripherals_realize(DeviceState *dev, Error **errp)
>      BCMSocPeripheralBaseState *s_base = BCM_SOC_PERIPHERALS_BASE(dev);
>      MemoryRegion *regs_mr;
>      MemoryRegion *mmio_mr;
> +    MemoryRegion *rng200_mr;
> +    MemoryRegion *thermal_mr;
> +    qemu_irq rng_200_irq;
>
>      int n;
>
> @@ -92,12 +98,20 @@ static void bcm2838_peripherals_realize(DeviceState *dev, Error **errp)
>      if (!sysbus_realize(SYS_BUS_DEVICE(&s->rng200), errp)) {
>          return;
>      }
> -    memory_region_add_subregion(
> -        &s_base->peri_mr, RNG_OFFSET,
> -        sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->rng200), 0));
> -    sysbus_connect_irq(SYS_BUS_DEVICE(&s->rng200), 0,
> -        qdev_get_gpio_in_named(DEVICE(&s_base->ic), BCM2835_IC_GPU_IRQ,
> -                               INTERRUPT_RNG));
> +    rng200_mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->rng200), 0);
> +    memory_region_add_subregion(&s_base->peri_mr, RNG_OFFSET, rng200_mr);
> +
> +    rng_200_irq = qdev_get_gpio_in_named(DEVICE(&s_base->ic),
> +                                         BCM2835_IC_GPU_IRQ, INTERRUPT_RNG);
> +    sysbus_connect_irq(SYS_BUS_DEVICE(&s->rng200), 0, rng_200_irq);

These parts related to the RNG should presumably have been in
the patch which added the RNG device.

> +
> +
> +    /* THERMAL */
> +    if (!sysbus_realize(SYS_BUS_DEVICE(&s->thermal), errp)) {
> +        return;
> +    }
> +    thermal_mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->thermal), 0);
> +    memory_region_add_subregion( &s->peri_low_mr, 0x15D2000, thermal_mr);
>
>      /* Extended Mass Media Controller 2 */
>      object_property_set_uint(OBJECT(&s->emmc2), "sd-spec-version", 3,
> @@ -198,6 +212,7 @@ static void bcm2838_peripherals_realize(DeviceState *dev, Error **errp)
>                               BCM2838_MPHI_SIZE);
>      memory_region_add_subregion(&s_base->peri_mr, BCM2838_MPHI_OFFSET,
>                                  &s->mphi_mr_alias);
> +
>      /* PCIe Root Complex */
>      if (!sysbus_realize(SYS_BUS_DEVICE(&s->pcie_host), errp)) {
>          return;

Stray extra whitespace change -- should probably be in whichever patch
is adding the PCI device to the SoC.

> diff --git a/hw/arm/raspi4b.c b/hw/arm/raspi4b.c
> index 7b5385b8dd..fda27d36cb 100644
> --- a/hw/arm/raspi4b.c
> +++ b/hw/arm/raspi4b.c
> @@ -67,7 +67,6 @@ static void raspi4_modify_dtb(const struct arm_boot_info *info, void *fdt)
>
>      /* Temporarily disable following devices until they are implemented*/
>      const char *to_be_removed_from_dt_as_wa[] = {
> -        "brcm,bcm2711-thermal",
>          "brcm,bcm2711-genet-v5",
>      };
>
> diff --git a/hw/misc/bcm2838_thermal.c b/hw/misc/bcm2838_thermal.c
> new file mode 100644
> index 0000000000..2301f657d0
> --- /dev/null
> +++ b/hw/misc/bcm2838_thermal.c
> @@ -0,0 +1,98 @@
> +/*
> + * BCM2838 dummy thermal sensor
> + *
> + * Copyright (C) 2022 Maksim Kopusov <maksim.kopusov@auriga.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/log.h"
> +#include "qapi/error.h"
> +#include "hw/misc/bcm2838_thermal.h"
> +#include "hw/registerfields.h"
> +#include "migration/vmstate.h"
> +#include "qemu/error-report.h"
> +
> +REG32(STAT, 0x200)
> +FIELD(STAT, DATA, 0, 10)
> +FIELD(STAT, VALID_1, 10, 1)
> +FIELD(STAT, VALID_2, 16, 1)
> +
> +#define BCM2838_THERMAL_SIZE 0xf00
> +
> +#define THERMAL_OFFSET_C 410040
> +#define THERMAL_COEFF  (-487.0f)
> +#define MILLIDEGREE_COEFF 1000
> +
> +static uint16_t bcm2838_thermal_temp2adc(int temp_C)
> +{
> +    return (temp_C * MILLIDEGREE_COEFF - THERMAL_OFFSET_C) / THERMAL_COEFF;
> +}
> +
> +static uint64_t bcm2838_thermal_read(void *opaque, hwaddr addr, unsigned size)
> +{
> +    uint32_t val = 0;
> +
> +    switch (addr) {
> +    case A_STAT:
> +        /* Temperature is always 25°C */
> +        val = FIELD_DP32(val, STAT, DATA, bcm2838_thermal_temp2adc(25));
> +        val = FIELD_DP32(val, STAT, VALID_1, 1);
> +        val = FIELD_DP32(val, STAT, VALID_2, 1);
> +
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s can't access addr: 0x%"PRIx64,

addr here is a hwaddr, so HWADDR_PRIx is the right format string.

> +                     TYPE_BCM2838_THERMAL, addr);
> +    }
> +    return val;
> +}

> diff --git a/hw/misc/meson.build b/hw/misc/meson.build
> index b899e6b596..386471a5e4 100644
> --- a/hw/misc/meson.build
> +++ b/hw/misc/meson.build
> @@ -91,7 +91,8 @@ system_ss.add(when: 'CONFIG_RASPI', if_true: files(
>    'bcm2835_thermal.c',
>    'bcm2835_cprman.c',
>    'bcm2835_powermgt.c',
> -  'bcm2838_rng200.c'
> +  'bcm2838_rng200.c',
> +  'bcm2838_thermal.c'

If you always keep a trailing comma at the end of this kind of list,
then when you add a new item to it you don't need to also edit
the previous line.

>  ))
>  system_ss.add(when: 'CONFIG_SLAVIO', if_true: files('slavio_misc.c'))
>  system_ss.add(when: 'CONFIG_ZYNQ', if_true: files('zynq_slcr.c'))

Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM