Re: [Qemu-devel] [PATCH] hw: Add test device for unittests execution

[Peter Maydell]

On 4 October 2012 04:49, Lucas Meneghel Rodrigues <address@hidden> wrote:
> Add a test device which supports the kvmctl ioports,
> so one can run the KVM unittest suite [1].
>
> Usage:
>
> qemu -device testdev
>
> 1) Removed port 0xf1, since now kvm-unit-tests use
>    serial
>
> 2) Removed exit code port 0xf4, since that can be
>    replaced by
>
> -device isa-debugexit,iobase=0xf4,access-size=2
>
> 3) Removed ram size port 0xd1, since guest memory
>    size can be retrieved from firmware, there's a
>    patch for kvm-unit-tests including an API to
>    retrieve that value.
>
> [1] Preliminary versions of this patch were posted
> to the mailing list about a year ago, I re-read the
> comments of the thread, and had guidance from
> Paolo about which ports to remove from the test
> device.

General remark: there's no documentation anywhere in
this patch. I don't necessarily mean user-facing docs,
but at least a descriptive comment saying what the
heck this device is and what it does would be helpful.


>
> CC: Paolo Bonzini <address@hidden>
> Signed-off-by: Gerd Hoffmann <address@hidden>
> Signed-off-by: Avi Kivity <address@hidden>
> Signed-off-by: Marcelo Tosatti <address@hidden>
> Signed-off-by: Lucas Meneghel Rodrigues <address@hidden>
> ---
>  hw/i386/Makefile.objs |   1 +
>  hw/testdev.c          | 131 
> ++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 132 insertions(+)
>  create mode 100644 hw/testdev.c
>
> diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
> index 8c764bb..64d2787 100644
> --- a/hw/i386/Makefile.objs
> +++ b/hw/i386/Makefile.objs
> @@ -11,5 +11,6 @@ obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
>  obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o 
> xen_pt_msi.o
>  obj-y += kvm/
>  obj-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o
> +obj-y += testdev.o

...the device is useful even in non-KVM configs, then?

>  obj-y := $(addprefix ../,$(obj-y))
> diff --git a/hw/testdev.c b/hw/testdev.c
> new file mode 100644
> index 0000000..44070f2
> --- /dev/null
> +++ b/hw/testdev.c
> @@ -0,0 +1,131 @@
> +#include <sys/mman.h>

This file needs a leading comment with the usual copyright/license/
description of what the file does.

> +#include "hw.h"
> +#include "qdev.h"
> +#include "isa.h"
> +
> +struct testdev {
> +    ISADevice dev;
> +    MemoryRegion iomem;
> +    CharDriverState *chr;
> +};
> +
> +#define TYPE_TESTDEV "testdev"
> +#define TESTDEV(obj) \
> +     OBJECT_CHECK(struct testdev, (obj), TYPE_TESTDEV)
> +
> +static void test_device_irq_line(void *opaque, uint32_t addr, uint32_t data)
> +{
> +    struct testdev *dev = opaque;
> +
> +    qemu_set_irq(isa_get_irq(&dev->dev, addr - 0x2000), !!data);
> +}
> +
> +static uint32 test_device_ioport_data;
> +
> +static void test_device_ioport_write(void *opaque, uint32_t addr, uint32_t 
> data)
> +{
> +    test_device_ioport_data = data;
> +}
> +
> +static uint32_t test_device_ioport_read(void *opaque, uint32_t addr)
> +{
> +    return test_device_ioport_data;
> +}
> +
> +static void test_device_flush_page(void *opaque, uint32_t addr, uint32_t 
> data)
> +{
> +    target_phys_addr_t len = 4096;
> +    void *a = cpu_physical_memory_map(data & ~0xffful, &len, 0);
> +
> +    mprotect(a, 4096, PROT_NONE);
> +    mprotect(a, 4096, PROT_READ|PROT_WRITE);
> +    cpu_physical_memory_unmap(a, len, 0, 0);
> +}
> +
> +static char *iomem_buf;
> +
> +static uint32_t test_iomem_readb(void *opaque, target_phys_addr_t addr)
> +{
> +    return iomem_buf[addr];
> +}
> +
> +static uint32_t test_iomem_readw(void *opaque, target_phys_addr_t addr)
> +{
> +    return *(uint16_t*)(iomem_buf + addr);
> +}
> +
> +static uint32_t test_iomem_readl(void *opaque, target_phys_addr_t addr)
> +{
> +    return *(uint32_t*)(iomem_buf + addr);
> +}
> +
> +static void test_iomem_writeb(void *opaque, target_phys_addr_t addr, 
> uint32_t val)
> +{
> +    iomem_buf[addr] = val;
> +}
> +
> +static void test_iomem_writew(void *opaque, target_phys_addr_t addr, 
> uint32_t val)
> +{
> +    *(uint16_t*)(iomem_buf + addr) = val;
> +}
> +
> +static void test_iomem_writel(void *opaque, target_phys_addr_t addr, 
> uint32_t val)
> +{
> +    *(uint32_t*)(iomem_buf + addr) = val;
> +}
> +
> +static const MemoryRegionOps test_iomem_ops = {
> +    .old_mmio = {
> +        .read = { test_iomem_readb, test_iomem_readw, test_iomem_readl, },
> +        .write = { test_iomem_writeb, test_iomem_writew, test_iomem_writel, 
> },
> +    },
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +};
> +
> +static int init_test_device(ISADevice *isa)
> +{
> +    struct testdev *dev = DO_UPCAST(struct testdev, dev, isa);
> +
> +    register_ioport_read(0xe0, 1, 1, test_device_ioport_read, dev);
> +    register_ioport_write(0xe0, 1, 1, test_device_ioport_write, dev);
> +    register_ioport_read(0xe0, 1, 2, test_device_ioport_read, dev);
> +    register_ioport_write(0xe0, 1, 2, test_device_ioport_write, dev);
> +    register_ioport_read(0xe0, 1, 4, test_device_ioport_read, dev);
> +    register_ioport_write(0xe0, 1, 4, test_device_ioport_write, dev);
> +    register_ioport_write(0xe4, 1, 4, test_device_flush_page, dev);
> +    register_ioport_write(0x2000, 24, 1, test_device_irq_line, NULL);
> +    iomem_buf = g_malloc0(0x10000);
> +    memory_region_init_io(&dev->iomem, &test_iomem_ops, dev,
> +                          "testdev", 0x10000);
> +    memory_region_add_subregion(isa_address_space(&dev->dev), 0xff000000,
> +                                                  &dev->iomem);
> +    return 0;
> +}
> +
> +static Property testdev_isa_properties[] = {
> +    DEFINE_PROP_CHR("chardev", struct testdev, chr),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void testdev_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    ISADeviceClass *k = ISA_DEVICE_CLASS(klass);
> +
> +    k->init = init_test_device;
> +    dc->props = testdev_isa_properties;
> +}
> +
> +static TypeInfo testdev_info = {
> +    .name           = "testdev",

Overly generic name?

> +    .parent         = TYPE_ISA_DEVICE,
> +    .instance_size  = sizeof(struct testdev),
> +    .class_init     = testdev_class_init,
> +};

Can this be generalised to not be specifically an ISA
device? (that's rather an x86-ism). Would the device be
useful for unit tests of other KVM architectures? Or
are we providing it purely for a legacy x86 testsuite?

> +
> +static void testdev_register_types(void)
> +{
> +    type_register_static(&testdev_info);
> +}
> +
> +type_init(testdev_register_types)
> --
> 1.7.11.4
>
>

thanks
-- PMM