Re: [Qemu-devel] PCI 64-bit BAR access with qemu

[Francois WELLENREITER <francois.wellenreiter@bull.net>]

Hi Max,

thank you for your answer. Actually, I hadn't confused.
I already thought to your proposal but I found that it was a really ugly 
solution (essentially because of the uint32_t to uint64_t silent 
conversion).
Isn't there any other (current or future) development that may fix it ?

             François

Le 12/10/2011 13:00, Max Filippov a écrit :
>>     I've read a few days ago that it was possible to emulate PCI device with
>> 64-bit BARs and have a real 64-bit memory access.
>> Thus, I've created a virtual device named toto accessible through a 64-bit
>> BAR
> You've probably confused an ability to locate BAR anywhere in 64-bit
> address space (such BAR actually spans 2 consecutive PCI BAR registers
> and has 100 in its 3 least significant bits) and an ability to access
> BAR-mapped memory in 64 bit items.
>
> You obviously want the latter but currently it is not implemented, see e.g.
>
> static inline DATA_TYPE glue(io_read, SUFFIX)(target_phys_addr_t physaddr,
>                                                target_ulong addr,
>                                                void *retaddr)
>
> definition in the softmmu_template.h.
>
> And it's quite simple to fix it, you only need to change
> io_{read,write} in the softmmu_template.h and extend
> io_mem_{read,write} loops in exec.c to 4 elements, taking care that
> io_mem_{read,write}[3] can pass uint64_t.
>