| Message ID | 1484247815-15279-3-git-send-email-peter.maydell@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
Peter Maydell <peter.maydell@linaro.org> writes: > Create a new "unimplemented" sysbus device, which simply accepts > all read and write accesses, and implements them as read-as-zero, > write-ignored, with logging of the access as LOG_UNIMP. > > This is useful for stubbing out bits of an SoC or board model > which haven't been written yet. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> This looks good: Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Is there any millage at being able to define areas on the command line or would we expect every usage of this to be from a board file in the source? It would be useful to link to this somewhere from the docs/wiki as a good example of a modern QDEV device boilerplate. It would make a change from telling people to "find a recent device and use it as a template" on IRC ;-) Paolo, Would this be in docs/ or on somewhere else? > --- > hw/misc/Makefile.objs | 2 + > include/hw/misc/unimp.h | 39 ++++++++++++++++++ > hw/misc/unimp.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 148 insertions(+) > create mode 100644 include/hw/misc/unimp.h > create mode 100644 hw/misc/unimp.c > > diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs > index 1a89615..898e4cc 100644 > --- a/hw/misc/Makefile.objs > +++ b/hw/misc/Makefile.objs > @@ -6,6 +6,8 @@ common-obj-$(CONFIG_SGA) += sga.o > common-obj-$(CONFIG_ISA_TESTDEV) += pc-testdev.o > common-obj-$(CONFIG_PCI_TESTDEV) += pci-testdev.o > > +common-obj-y += unimp.o > + > obj-$(CONFIG_VMPORT) += vmport.o > > # ARM devices > diff --git a/include/hw/misc/unimp.h b/include/hw/misc/unimp.h > new file mode 100644 > index 0000000..3462d85 > --- /dev/null > +++ b/include/hw/misc/unimp.h > @@ -0,0 +1,39 @@ > +/* > + * "Unimplemented" device > + * > + * Copyright Linaro Limited, 2017 > + * Written by Peter Maydell > + */ > + > +#ifndef HW_MISC_UNIMP_H > +#define HW_MISC_UNIMP_H > + > +#define TYPE_UNIMPLEMENTED_DEVICE "unimplemented-device" > + > +/** > + * create_unimplemented_device: create and map a dummy device > + * @name: name of the device for debug logging > + * @base: base address of the device's MMIO region > + * @size: size of the device's MMIO region > + * > + * This utility function creates and maps an instance of unimplemented-device, > + * which is a dummy device which simply logs all guest accesses to > + * it via the qemu_log LOG_UNIMP debug log. > + * The device is mapped at priority -1000, which means that you can > + * use it to cover a large region and then map other devices on top of it > + * if necessary. > + */ > +static inline void create_unimplemented_device(const char *name, > + hwaddr base, > + hwaddr size) > +{ > + DeviceState *dev = qdev_create(NULL, TYPE_UNIMPLEMENTED_DEVICE); > + > + qdev_prop_set_string(dev, "name", name); > + qdev_prop_set_uint64(dev, "size", size); > + qdev_init_nofail(dev); > + > + sysbus_mmio_map_overlap(SYS_BUS_DEVICE(dev), 0, base, -1000); > +} > + > +#endif > diff --git a/hw/misc/unimp.c b/hw/misc/unimp.c > new file mode 100644 > index 0000000..bcbb585 > --- /dev/null > +++ b/hw/misc/unimp.c > @@ -0,0 +1,107 @@ > +/* "Unimplemented" device > + * > + * This is a dummy device which accepts and logs all accesses. > + * It's useful for stubbing out regions of an SoC or board > + * map which correspond to devices that have not yet been > + * implemented. This is often sufficient to placate initial > + * guest device driver probing such that the system will > + * come up. > + * > + * Copyright Linaro Limited, 2017 > + * Written by Peter Maydell > + */ > + > +#include "qemu/osdep.h" > +#include "hw/hw.h" > +#include "hw/sysbus.h" > +#include "hw/misc/unimp.h" > +#include "qemu/log.h" > +#include "qapi/error.h" > + > +#define UNIMPLEMENTED_DEVICE(obj) \ > + OBJECT_CHECK(UnimplementedDeviceState, (obj), TYPE_UNIMPLEMENTED_DEVICE) > + > +typedef struct { > + SysBusDevice parent_obj; > + MemoryRegion iomem; > + char *name; > + uint64_t size; > +} UnimplementedDeviceState; > + > +static uint64_t unimp_read(void *opaque, hwaddr offset, unsigned size) > +{ > + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); > + > + qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read " > + "(size %d, offset 0x%" HWADDR_PRIx ")\n", > + s->name, size, offset); > + return 0; > +} > + > +static void unimp_write(void *opaque, hwaddr offset, > + uint64_t value, unsigned size) > +{ > + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); > + > + qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write " > + "(size %d, value 0x%" PRIx64 > + ", offset 0x%" HWADDR_PRIx ")\n", > + s->name, size, value, offset); > +} > + > +static const MemoryRegionOps unimp_ops = { > + .read = unimp_read, > + .write = unimp_write, > + .impl.min_access_size = 1, > + .impl.max_access_size = 8, > + .valid.min_access_size = 1, > + .valid.max_access_size = 8, > + .endianness = DEVICE_NATIVE_ENDIAN, > +}; > + > +static void unimp_realize(DeviceState *dev, Error **errp) > +{ > + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(dev); > + > + if (s->size == 0) { > + error_setg(errp, "property 'size' not specified or zero"); > + return; > + } > + > + if (s->name == NULL) { > + error_setg(errp, "property 'name' not specified"); > + return; > + } > + > + memory_region_init_io(&s->iomem, OBJECT(s), &unimp_ops, s, > + s->name, s->size); > + sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem); > +} > + > +static Property unimp_properties[] = { > + DEFINE_PROP_UINT64("size", UnimplementedDeviceState, size, 0), > + DEFINE_PROP_STRING("name", UnimplementedDeviceState, name), > + DEFINE_PROP_END_OF_LIST(), > +}; > + > +static void unimp_class_init(ObjectClass *klass, void *data) > +{ > + DeviceClass *dc = DEVICE_CLASS(klass); > + > + dc->realize = unimp_realize; > + dc->props = unimp_properties; > +} > + > +static const TypeInfo unimp_info = { > + .name = TYPE_UNIMPLEMENTED_DEVICE, > + .parent = TYPE_SYS_BUS_DEVICE, > + .instance_size = sizeof(UnimplementedDeviceState), > + .class_init = unimp_class_init, > +}; > + > +static void unimp_register_types(void) > +{ > + type_register_static(&unimp_info); > +} > + > +type_init(unimp_register_types) -- Alex Bennée
On 27 January 2017 at 14:33, Alex Bennée <alex.bennee@linaro.org> wrote: > Is there any millage at being able to define areas on the command line > or would we expect every usage of this to be from a board file in the > source? Command line syntax is for life, not just for Christmas, so I'd rather we didn't add any until somebody comes up with a genuine use case for it. thanks -- PMM
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs index 1a89615..898e4cc 100644 --- a/hw/misc/Makefile.objs +++ b/hw/misc/Makefile.objs @@ -6,6 +6,8 @@ common-obj-$(CONFIG_SGA) += sga.o common-obj-$(CONFIG_ISA_TESTDEV) += pc-testdev.o common-obj-$(CONFIG_PCI_TESTDEV) += pci-testdev.o +common-obj-y += unimp.o + obj-$(CONFIG_VMPORT) += vmport.o # ARM devices diff --git a/include/hw/misc/unimp.h b/include/hw/misc/unimp.h new file mode 100644 index 0000000..3462d85 --- /dev/null +++ b/include/hw/misc/unimp.h @@ -0,0 +1,39 @@ +/* + * "Unimplemented" device + * + * Copyright Linaro Limited, 2017 + * Written by Peter Maydell + */ + +#ifndef HW_MISC_UNIMP_H +#define HW_MISC_UNIMP_H + +#define TYPE_UNIMPLEMENTED_DEVICE "unimplemented-device" + +/** + * create_unimplemented_device: create and map a dummy device + * @name: name of the device for debug logging + * @base: base address of the device's MMIO region + * @size: size of the device's MMIO region + * + * This utility function creates and maps an instance of unimplemented-device, + * which is a dummy device which simply logs all guest accesses to + * it via the qemu_log LOG_UNIMP debug log. + * The device is mapped at priority -1000, which means that you can + * use it to cover a large region and then map other devices on top of it + * if necessary. + */ +static inline void create_unimplemented_device(const char *name, + hwaddr base, + hwaddr size) +{ + DeviceState *dev = qdev_create(NULL, TYPE_UNIMPLEMENTED_DEVICE); + + qdev_prop_set_string(dev, "name", name); + qdev_prop_set_uint64(dev, "size", size); + qdev_init_nofail(dev); + + sysbus_mmio_map_overlap(SYS_BUS_DEVICE(dev), 0, base, -1000); +} + +#endif diff --git a/hw/misc/unimp.c b/hw/misc/unimp.c new file mode 100644 index 0000000..bcbb585 --- /dev/null +++ b/hw/misc/unimp.c @@ -0,0 +1,107 @@ +/* "Unimplemented" device + * + * This is a dummy device which accepts and logs all accesses. + * It's useful for stubbing out regions of an SoC or board + * map which correspond to devices that have not yet been + * implemented. This is often sufficient to placate initial + * guest device driver probing such that the system will + * come up. + * + * Copyright Linaro Limited, 2017 + * Written by Peter Maydell + */ + +#include "qemu/osdep.h" +#include "hw/hw.h" +#include "hw/sysbus.h" +#include "hw/misc/unimp.h" +#include "qemu/log.h" +#include "qapi/error.h" + +#define UNIMPLEMENTED_DEVICE(obj) \ + OBJECT_CHECK(UnimplementedDeviceState, (obj), TYPE_UNIMPLEMENTED_DEVICE) + +typedef struct { + SysBusDevice parent_obj; + MemoryRegion iomem; + char *name; + uint64_t size; +} UnimplementedDeviceState; + +static uint64_t unimp_read(void *opaque, hwaddr offset, unsigned size) +{ + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); + + qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read " + "(size %d, offset 0x%" HWADDR_PRIx ")\n", + s->name, size, offset); + return 0; +} + +static void unimp_write(void *opaque, hwaddr offset, + uint64_t value, unsigned size) +{ + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque); + + qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write " + "(size %d, value 0x%" PRIx64 + ", offset 0x%" HWADDR_PRIx ")\n", + s->name, size, value, offset); +} + +static const MemoryRegionOps unimp_ops = { + .read = unimp_read, + .write = unimp_write, + .impl.min_access_size = 1, + .impl.max_access_size = 8, + .valid.min_access_size = 1, + .valid.max_access_size = 8, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void unimp_realize(DeviceState *dev, Error **errp) +{ + UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(dev); + + if (s->size == 0) { + error_setg(errp, "property 'size' not specified or zero"); + return; + } + + if (s->name == NULL) { + error_setg(errp, "property 'name' not specified"); + return; + } + + memory_region_init_io(&s->iomem, OBJECT(s), &unimp_ops, s, + s->name, s->size); + sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem); +} + +static Property unimp_properties[] = { + DEFINE_PROP_UINT64("size", UnimplementedDeviceState, size, 0), + DEFINE_PROP_STRING("name", UnimplementedDeviceState, name), + DEFINE_PROP_END_OF_LIST(), +}; + +static void unimp_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = unimp_realize; + dc->props = unimp_properties; +} + +static const TypeInfo unimp_info = { + .name = TYPE_UNIMPLEMENTED_DEVICE, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(UnimplementedDeviceState), + .class_init = unimp_class_init, +}; + +static void unimp_register_types(void) +{ + type_register_static(&unimp_info); +} + +type_init(unimp_register_types)
Create a new "unimplemented" sysbus device, which simply accepts all read and write accesses, and implements them as read-as-zero, write-ignored, with logging of the access as LOG_UNIMP. This is useful for stubbing out bits of an SoC or board model which haven't been written yet. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- hw/misc/Makefile.objs | 2 + include/hw/misc/unimp.h | 39 ++++++++++++++++++ hw/misc/unimp.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 148 insertions(+) create mode 100644 include/hw/misc/unimp.h create mode 100644 hw/misc/unimp.c -- 2.7.4