[SLOF] [PATCH v1 09/27] virtio: add 64-bit virtio helpers for 1.0

[Alexey Kardashevskiy]

On 01/14/2016 09:58 PM, Nikunj A Dadhania wrote:
> Alexey Kardashevskiy <aik at ozlabs.ru> writes:
>
>> On 01/13/2016 10:16 PM, Nikunj A Dadhania wrote:
>>> Signed-off-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
>>> ---
>>>    lib/libvirtio/virtio.c | 18 ++++++++++++++++++
>>>    lib/libvirtio/virtio.h |  2 ++
>>>    2 files changed, 20 insertions(+)
>>>
>>> diff --git a/lib/libvirtio/virtio.c b/lib/libvirtio/virtio.c
>>> index 77676c7..aa4a45b 100644
>>> --- a/lib/libvirtio/virtio.c
>>> +++ b/lib/libvirtio/virtio.c
>>> @@ -81,6 +81,24 @@ struct virtio_dev_common {
>>>    	le64 q_used;
>>>    } __attribute__ ((packed));
>>>
>>> +void virtio_write64(void *addr, uint64_t val)
>>> +{
>>> +	uint32_t hi = (val >> 32) & 0xFFFFFFFF;
>>> +	uint32_t lo = val & 0xFFFFFFFF;
>>> +
>>> +	ci_write_32(addr, cpu_to_le32(lo));
>>> +	ci_write_32(addr + 4, cpu_to_le32(hi));
>>> +}
>>
>>
>> ci_write_64 and cpu_to_le64 are there, why these new helpers?
>
> Thats not the same here if you notice. virtio needs the 64bit writes to
> be broken to high and low and write 32bits.


Put this to commit log then.

>
>>
>>
>>> +
>>> +uint64_t virtio_read64(void *addr)
>>> +{
>>> +	uint64_t hi, lo;
>>> +
>>> +	lo = le32_to_cpu(ci_read_32(addr));
>>> +	hi = le32_to_cpu(ci_read_32(addr + 4));
>>> +	return (hi << 32) | lo;
>>> +}
>>> +
>>>    static void virtio_process_cap(struct virtio_device *dev, uint8_t cap_ptr)
>>>    {
>>>    	struct virtio_cap *cap;
>>> diff --git a/lib/libvirtio/virtio.h b/lib/libvirtio/virtio.h
>>> index 537862b..aa75c2d 100644
>>> --- a/lib/libvirtio/virtio.h
>>> +++ b/lib/libvirtio/virtio.h
>>> @@ -106,6 +106,8 @@ struct vqs {
>>>    /* Parts of the virtqueue are aligned on a 4096 byte page boundary */
>>>    #define VQ_ALIGN(addr)	(((addr) + 0xfff) & ~0xfff)
>>>
>>> +extern void virtio_write64(void *addr, uint64_t val);
>>> +extern uint64_t virtio_read64(void *addr);
>>>    extern unsigned long virtio_vring_size(unsigned int qsize);
>>>    extern unsigned int virtio_get_qsize(struct virtio_device *dev, int queue);
>>>    extern struct vring_desc *virtio_get_vring_desc(struct virtio_device *dev, int queue);
>>>
>>
>>
>> --
>> Alexey
>


-- 
Alexey