[Skiboot] [PATCH v2 14/17] xive/p9: introduce NVT_SHIFT

[Oliver O'Halloran]

On Thu, 2019-09-12 at 19:22 +0200, Cédric Le Goater wrote:
> This defines the size of our VP space.
> 
> Signed-off-by: Cédric Le Goater <clg at kaod.org>
> ---
>  hw/xive.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/xive.c b/hw/xive.c
> index 6572a45f57be..8c92a612a5fa 100644
> --- a/hw/xive.c
> +++ b/hw/xive.c
> @@ -189,7 +189,10 @@
>   *
>   * XXX Adjust that based on BAR value ?
>   */
> -#define MAX_VP_ORDER		19	/* 512k */
> +

> +#define NVT_SHIFT		19	/* in sync with EQ_W6_NVT_INDEX */

What is the being kept in sync with? The width of the "Base NVT Block
Offset (Index)" field in the XIVE spec? Is that a HW specific value or
is there some software configuration that I'm not understanding here?

> +#define MAX_VP_ORDER		NVT_SHIFT /* 512k */
>  #define MAX_VP_COUNT		(1ul << MAX_VP_ORDER)
>  #define VP_PER_PAGE		(0x10000 / 64) // Use sizeof ?
>  #define IND_VP_TABLE_SIZE	((MAX_VP_COUNT / VP_PER_PAGE) * 8)
> @@ -4042,7 +4045,7 @@ static int64_t opal_xive_get_vp_info(uint64_t vp_id,
>  	}
>  
>  	if (out_cam_value)
> -		*out_cam_value = (blk << 19) | idx;
> +		*out_cam_value = (blk << NVT_SHIFT) | idx;
>  
>  	if (out_report_cl_pair) {
>  		*out_report_cl_pair = ((uint64_t)(vp->w6 & 0x0fffffff)) << 32;