Re: [Qemu-devel] [RFC PATCH v2 05/13] spapr_pci: Introduce a liobn number generating macros

[Alexander Graf <agraf@suse.de>]

On 15.08.14 12:12, Alexey Kardashevskiy wrote:
> We are going to have multiple DMA windows per PHB and we want them to
> migrate so we need a predictable way of assigning LIOBNs.
> 
> This introduces a macro which makes up a LIOBN from fixed prefix,
> PHB index (unique PHB id) and window number.
> 
> This introduces a SPAPR_PCI_DMA_WINDOW_NUM() to know the window number
> from LIOBN, will be used in next patch(es) to distinguish the default
> 32bit windows from dynamic windows.
> 
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> ---
>  hw/ppc/spapr_pci.c     | 2 +-
>  include/hw/ppc/spapr.h | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 5c46c0d..17eb0d8 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -529,7 +529,7 @@ static void spapr_phb_realize(DeviceState *dev, Error **errp)
>          }
>  
>          sphb->buid = SPAPR_PCI_BASE_BUID + sphb->index;
> -        sphb->dma_liobn = SPAPR_PCI_BASE_LIOBN + sphb->index;
> +        sphb->dma_liobn = SPAPR_PCI_LIOBN(sphb->index, 0);
>  
>          windows_base = SPAPR_PCI_WINDOW_BASE
>              + sphb->index * SPAPR_PCI_WINDOW_SPACING;
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index c9d6c6c..782519a 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -443,7 +443,8 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
>  #define SPAPR_TCE_PAGE_MASK    (SPAPR_TCE_PAGE_SIZE - 1)
>  
>  #define SPAPR_VIO_BASE_LIOBN    0x00000000
> -#define SPAPR_PCI_BASE_LIOBN    0x80000000
> +#define SPAPR_PCI_LIOBN(i, n)   (0x80000000 | ((i) << 8) | (n))
> +#define SPAPR_PCI_DMA_WINDOW_NUM(liobn) ((liobn) & 0xff)

Good idea. Mind to convert VIO as well to make them consistent?


Alex