Re: [Qemu-devel] [PATCH] hw/misc/blob-loader: add a generic blob loader

[Paolo Bonzini]

Il 02/01/2014 06:50, Peter Crosthwaite ha scritto:
> On Thu, Jan 2, 2014 at 3:35 PM, Li Guang <address@hidden> wrote:
>> this blob loader will be used to load a specified
>> blob into a specified RAM address.
>>
> 
> Suggested-by: Peter Crosthwaite <address@hidden>
> 
>> Signed-off-by: Li Guang <address@hidden>
>> ---
>> it can be used now for allwinner-a10, like:
>> "-device blob-loader,addr=0x43000000,file=/path/script.bin"
>>
>> reference:
>> http://linux-sunxi.org/Sunxi-tools
>>
>> script file address:
>> http://dl.dbank.com/c00aonvlmw
>>
>> Thanks to Peter Crosthwaite for the idea!
>> ---
>>  default-configs/arm-softmmu.mak |    2 +
>>  hw/misc/Makefile.objs           |    2 +
>>  hw/misc/blob-loader.c           |   75 
>> +++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 79 insertions(+), 0 deletions(-)
>>  create mode 100644 hw/misc/blob-loader.c
>>
>> diff --git a/default-configs/arm-softmmu.mak 
>> b/default-configs/arm-softmmu.mak
>> index ce1d620..50c71a6 100644
>> --- a/default-configs/arm-softmmu.mak
>> +++ b/default-configs/arm-softmmu.mak
>> @@ -87,3 +87,5 @@ CONFIG_INTEGRATOR_DEBUG=y
>>  CONFIG_ALLWINNER_A10_PIT=y
>>  CONFIG_ALLWINNER_A10_PIC=y
>>  CONFIG_ALLWINNER_A10=y
>> +
>> +CONFIG_BLOB_LOADER=y
> 
> This shouldn't be arm specific. I would make the argument that the
> blob loader has global validity.
> 
>> diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
>> index f674365..df28288 100644
>> --- a/hw/misc/Makefile.objs
>> +++ b/hw/misc/Makefile.objs
>> @@ -42,3 +42,5 @@ obj-$(CONFIG_SLAVIO) += slavio_misc.o
>>  obj-$(CONFIG_ZYNQ) += zynq_slcr.o
>>
>>  obj-$(CONFIG_PVPANIC) += pvpanic.o
>> +
>> +obj-$(CONFIG_BLOB_LOADER) += blob-loader.o
>> diff --git a/hw/misc/blob-loader.c b/hw/misc/blob-loader.c
>> new file mode 100644
>> index 0000000..d7f1408
>> --- /dev/null
>> +++ b/hw/misc/blob-loader.c
>> @@ -0,0 +1,75 @@
>> +#include "hw/sysbus.h"
>> +#include "hw/devices.h"
>> +#include "hw/loader.h"
>> +#include "qemu/error-report.h"
>> +
>> +typedef struct BlobLoaderState {
> 
> /*< private >/*
> 
>> +    DeviceState qdev;
> 
> parent_obj;
> 
> /*< public >/*
> 
>> +    uint32_t addr;
> 
> uint64_t or hwaddr. Blob loading shouldn't be limited to 32 bit.
> 
>> +    char *file;
>> +} BlobLoaderState;
>> +
>> +#define TYPE_BLOB_LOADER "blob-loader"
>> +#define BLOB_LOADER(obj) OBJECT_CHECK(BlobLoaderState, (obj), 
>> TYPE_BLOB_LOADER)
>> +
>> +static Property blob_loader_props[] = {
>> +    DEFINE_PROP_UINT32("addr", BlobLoaderState, addr, 0),
>> +    DEFINE_PROP_STRING("file", BlobLoaderState, file),
>> +    DEFINE_PROP_END_OF_LIST(),
>> +};
>> +
>> +static void do_blob_load(BlobLoaderState *s)
>> +{
>> +    char *file_name;
>> +    int file_size;
>> +
>> +    if  (s->file == NULL) {
>> +        error_report("please spicify a file for blob loader\n");
>> +        return;
> 
> Should you exit(1)? Better yet, return true for error and ..
> 
>> +    }
>> +    file_name = qemu_find_file(QEMU_FILE_TYPE_BIOS, s->file);
>> +    if (file_name == NULL) {
>> +        error_report("can't find %s\n", s->file);
>> +        return;
>> +    }
>> +    file_size = get_image_size(file_name);
>> +    if (file_size < 0) {
>> +        error_report("can't get file size of %s\n", file_name);
>> +        return;
>> +    }
>> +    if (load_image_targphys(file_name, s->addr, file_size) < 0) {
>> +        error_report("can't load %s\n", file_name);
>> +        return;
>> +    }
>> +}
>> +
>> +static int blob_loader_init(DeviceState *dev)
>> +{
>> +    BlobLoaderState *s = BLOB_LOADER(dev);
>> +
>> +    do_blob_load(s);
> 
> exit(1) here.

No, please use "realize" and avoid init.  This way you can use an Error*
to report the error.

Also, the actual load_image_targphys call probably should be done in a
reset handler, not at realize time.

Paolo

>> +    return 0;
>> +}
>> +
>> +static void blob_loader_class_init(ObjectClass *klass, void *data)
> 
> s/klass/oc.

Actually klass is quite commonly used.

Paolo

>> +{
>> +    DeviceClass *dc = DEVICE_CLASS(klass);
>> +
>> +    dc->props = blob_loader_props;
>> +    dc->desc = "blob loader";
>> +    dc->init = blob_loader_init;
> 
> I'm wondering whether blob loading is actually a reset step not an
> init. Will doing it at init will play foul with VMSD, as your blob
> loader will trample non-reset state on machine restore?
> 
> Regards,
> Peter
> 
>> +}
>> +
>> +static TypeInfo blob_loader_info = {
>> +    .name                  = TYPE_BLOB_LOADER,
>> +    .parent                = TYPE_DEVICE,
>> +    .instance_size         = sizeof(BlobLoaderState),
>> +    .class_init            = blob_loader_class_init,
>> +};
>> +
>> +static void blob_loader_register_type(void)
>> +{
>> +    type_register_static(&blob_loader_info);
>> +}
>> +
>> +type_init(blob_loader_register_type)
>> --
>> 1.7.2.5
>>
>>
> 
>