Re: [Qemu-devel] [PATCH RESENT] msix: allow byte and word reading from mmio

[Bernhard Kohl <bernhard.kohl@nsn.com>]

Am 22.08.2010 23:34, schrieb ext Anthony Liguori:
> On 08/19/2010 07:56 AM, Bernhard Kohl wrote:
>    
>> It's legal that the guest reads a single byte or word from mmio.
>> I have an OS which reads single bytes and it works fine on real
>> hardware. Maybe this happens due to casting.
>>
>> Signed-off-by: Bernhard Kohl<bernhard.kohl@nsn.com>
>>
>>      
> Hi Michael,
>
> I'm looking for this to come through your tree unless you disagree.
>
> Regards,
>
> Anthony Liguori
>    

Hi,

could you please look at this again?

Thanks
Bernhard

>    
>> ---
>>    hw/msix.c |   20 ++++++++++++++++----
>>    1 files changed, 16 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/msix.c b/hw/msix.c
>> index d99403a..7dac7f7 100644
>> --- a/hw/msix.c
>> +++ b/hw/msix.c
>> @@ -100,10 +100,22 @@ static uint32_t msix_mmio_readl(void *opaque, target_phys_addr_t addr)
>>        return pci_get_long(page + offset);
>>    }
>>
>> -static uint32_t msix_mmio_read_unallowed(void *opaque, target_phys_addr_t addr)
>> +static uint32_t msix_mmio_readw(void *opaque, target_phys_addr_t addr)
>>    {
>> -    fprintf(stderr, "MSI-X: only dword read is allowed!\n");
>> -    return 0;
>> +    PCIDevice *dev = opaque;
>> +    unsigned int offset = addr&   (MSIX_PAGE_SIZE - 1)&   ~0x1;
>> +    void *page = dev->msix_table_page;
>> +
>> +    return pci_get_word(page + offset);
>> +}
>> +
>> +static uint32_t msix_mmio_readb(void *opaque, target_phys_addr_t addr)
>> +{
>> +    PCIDevice *dev = opaque;
>> +    unsigned int offset = addr&   (MSIX_PAGE_SIZE - 1);
>> +    void *page = dev->msix_table_page;
>> +
>> +    return pci_get_byte(page + offset);
>>    }
>>
>>    static uint8_t msix_pending_mask(int vector)
>> @@ -198,7 +210,7 @@ static CPUWriteMemoryFunc * const msix_mmio_write[] = {
>>    };
>>
>>    static CPUReadMemoryFunc * const msix_mmio_read[] = {
>> -    msix_mmio_read_unallowed, msix_mmio_read_unallowed, msix_mmio_readl
>> +    msix_mmio_readb, msix_mmio_readw, msix_mmio_readl
>>    };
>>
>>    /* Should be called from device's map method. */
>>
>>      
>
>