Philippe Mathieu-Daudé <f4...@amsat.org> writes:
> We will soon implement the SYS_timer. This timer is used by Linux > in the thermal subsystem, so once available, the subsystem will be > enabled and poll the temperature sensors. We need to provide the > minimum required to keep Linux booting. > > Add a dummy thermal sensor returning ~25°C based on: > https://github.com/raspberrypi/linux/blob/rpi-5.3.y/drivers/thermal/broadcom/bcm2835_thermal.c > > Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org> > --- > checkpatch warning: > WARNING: added, moved or deleted file(s), does MAINTAINERS need updating? > This is OK because the regex are: > > F: hw/*/bcm283* > F: include/hw/*/bcm283* > --- > hw/misc/Makefile.objs | 1 + > hw/misc/bcm2835_thermal.c | 109 ++++++++++++++++++++++++++++++ > include/hw/misc/bcm2835_thermal.h | 27 ++++++++ > 3 files changed, 137 insertions(+) > create mode 100644 hw/misc/bcm2835_thermal.c > create mode 100644 include/hw/misc/bcm2835_thermal.h > > diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs > index a150680966..c89f3816a5 100644 > --- a/hw/misc/Makefile.objs > +++ b/hw/misc/Makefile.objs > @@ -53,6 +53,7 @@ common-obj-$(CONFIG_OMAP) += omap_tap.o > common-obj-$(CONFIG_RASPI) += bcm2835_mbox.o > common-obj-$(CONFIG_RASPI) += bcm2835_property.o > common-obj-$(CONFIG_RASPI) += bcm2835_rng.o > +common-obj-$(CONFIG_RASPI) += bcm2835_thermal.o > common-obj-$(CONFIG_SLAVIO) += slavio_misc.o > common-obj-$(CONFIG_ZYNQ) += zynq_slcr.o > common-obj-$(CONFIG_ZYNQ) += zynq-xadc.o > diff --git a/hw/misc/bcm2835_thermal.c b/hw/misc/bcm2835_thermal.c > new file mode 100644 > index 0000000000..bac23f21ea > --- /dev/null > +++ b/hw/misc/bcm2835_thermal.c > @@ -0,0 +1,109 @@ > +/* > + * BCM2835 dummy thermal sensor > + * > + * Copyright (C) 2019 Philippe Mathieu-Daudé <f4...@amsat.org> > + * > + * SPDX-License-Identifier: GPL-2.0-or-later > + */ > +#include "qemu/osdep.h" > +#include "hw/sysbus.h" > +#include "hw/misc/bcm2835_thermal.h" > +#include "qemu/log.h" > +#include "qapi/error.h" > +#include "hw/registerfields.h" > + > +REG32(CTL, 0) > +FIELD(CTL, POWER_DOWN, 0, 1) > +FIELD(CTL, RESET, 1, 1) > +FIELD(CTL, BANDGAP_CTRL, 2, 3) > +FIELD(CTL, INTERRUPT_ENABLE, 5, 1) > +FIELD(CTL, DIRECT, 6, 1) > +FIELD(CTL, INTERRUPT_CLEAR, 7, 1) > +FIELD(CTL, HOLD, 8, 10) > +FIELD(CTL, RESET_DELAY, 18, 8) > +FIELD(CTL, REGULATOR_ENABLE, 26, 1) > + > +REG32(STAT, 4) > +FIELD(STAT, DATA, 0, 10) > +FIELD(STAT, VALID, 10, 1) > +FIELD(STAT, INTERRUPT, 11, 1) > + > +#define THERMAL_OFFSET_C 412 > +#define THERMAL_COEFF (-0.538f) > + > +static uint16_t bcm2835_thermal_temp2adc(int temp_C) > +{ > + return (temp_C - THERMAL_OFFSET_C) / THERMAL_COEFF; > +} > + > +static uint64_t bcm2835_thermal_read(void *opaque, hwaddr addr, unsigned > size) > +{ > + Bcm2835ThermalState *s = BCM2835_THERMAL(opaque); > + uint32_t val = 0; > + > + switch (addr) { > + case A_CTL: > + val = s->ctl; > + break; > + case A_STAT: > + val = FIELD_DP32(bcm2835_thermal_temp2adc(25), STAT, VALID, true); > + break; > + default: > + g_assert_not_reached(); Will a unaligned read already have faulted and delivered an exception to the guest? As this access it controlled by the guest it could potentially take down QEMU. Perhaps it should be a LOG_GUEST_ERROR as bellow? > + } > + return val; > +} > + > +static void bcm2835_thermal_write(void *opaque, hwaddr addr, > + uint64_t value, unsigned size) > +{ > + Bcm2835ThermalState *s = BCM2835_THERMAL(opaque); > + > + switch (addr) { > + case A_CTL: > + s->ctl = value; > + break; > + default: > + qemu_log_mask(LOG_GUEST_ERROR, "%s: write 0x%" PRIx64 > + " to 0x%" HWADDR_PRIx "\n", > + __func__, value, addr); > + } > +} > + > +static const MemoryRegionOps bcm2835_thermal_ops = { > + .read = bcm2835_thermal_read, > + .write = bcm2835_thermal_write, > + .impl.max_access_size = 4, > + .valid.min_access_size = 4, > + .endianness = DEVICE_NATIVE_ENDIAN, > +}; > + > +static void bcm2835_thermal_realize(DeviceState *dev, Error **errp) > +{ > + Bcm2835ThermalState *s = BCM2835_THERMAL(dev); > + > + memory_region_init_io(&s->iomem, OBJECT(s), &bcm2835_thermal_ops, > + s, TYPE_BCM2835_THERMAL, 8); > + sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem); > +} > + > +static void bcm2835_thermal_class_init(ObjectClass *klass, void *data) > +{ > + DeviceClass *dc = DEVICE_CLASS(klass); > + > + dc->realize = bcm2835_thermal_realize; > +} > + > +static const TypeInfo bcm2835_thermal_info = { > + .name = TYPE_BCM2835_THERMAL, > + .parent = TYPE_SYS_BUS_DEVICE, > + .instance_size = sizeof(Bcm2835ThermalState), > + .class_init = bcm2835_thermal_class_init, > +}; > + > +static void bcm2835_thermal_register_types(void) > +{ > + type_register_static(&bcm2835_thermal_info); > +} > + > +type_init(bcm2835_thermal_register_types) > diff --git a/include/hw/misc/bcm2835_thermal.h > b/include/hw/misc/bcm2835_thermal.h > new file mode 100644 > index 0000000000..f85cce7214 > --- /dev/null > +++ b/include/hw/misc/bcm2835_thermal.h > @@ -0,0 +1,27 @@ > +/* > + * BCM2835 dummy thermal sensor > + * > + * Copyright (C) 2019 Philippe Mathieu-Daudé <f4...@amsat.org> > + * > + * SPDX-License-Identifier: GPL-2.0-or-later > + */ > +#ifndef HW_MISC_BCM2835_THERMAL_H > +#define HW_MISC_BCM2835_THERMAL_H > + > +#include "hw/qdev-properties.h" > +#include "hw/sysbus.h" > + > +#define TYPE_BCM2835_THERMAL "bcm2835-thermal" > + > +#define BCM2835_THERMAL(obj) \ > + OBJECT_CHECK(Bcm2835ThermalState, (obj), TYPE_BCM2835_THERMAL) > + > +typedef struct { > + /*< private >*/ > + SysBusDevice parent_obj; > + /*< public >*/ > + MemoryRegion iomem; > + uint32_t ctl; > +} Bcm2835ThermalState; > + > +#endif Otherwise: Reviewed-by: Alex Bennée <alex.ben...@linaro.org> -- Alex Bennée
