[Skiboot] [PATCH RFC] core/affinity: Fix NUMA node associativity on P8 and P8NVL

[Gavin Shan]

On Fri, Feb 10, 2017 at 04:52:10PM +1100, Gavin Shan wrote:
>We have variable distances from Node-A to Node-B on different machines
>as below:
>
>   Machine    CPU        A <-> A     A <-> B
>   ------------------------------------------
>   Tuleta     POWER8E    10          20
>   Firestone  POWER8     10          40
>   Garrison   POWER8NVL  10          40
>
>This fixes the distance between Node-A and Node-B to 20 for all POWER8
>platforms, which is the value defined by Linux kernel. After the patch
>is applied, we have:
>
>   Machine    CPU        A <-> A     A <-> B
>   ------------------------------------------
>   Tuleta     POWER8E    10          20
>   Firestone  POWER8     10          40
>   Garrison   POWER8NVL  10          40
>


Please ignore this. the result after the patch isn't updated accordingly.
A revised one is to be sent shortly. The result after the patch should
be as below:

   Machine    CPU        A <-> A     A <-> B
   ------------------------------------------
   Tuleta     POWER8E    10          20
   Firestone  POWER8     10          20
   Garrison   POWER8NVL  10          20

Thanks,
Gavin

>Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
>---
> core/affinity.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
>diff --git a/core/affinity.c b/core/affinity.c
>index 9f489d3..64c1fda 100644
>--- a/core/affinity.c
>+++ b/core/affinity.c
>@@ -67,6 +67,7 @@ static uint32_t get_chip_node_id(struct proc_chip *chip)
>
> void add_associativity_ref_point(void)
> {
>+	unsigned long pvr = mfspr(SPR_PVR);
> 	int ref2 = 0x4;
>
> 	/*
>@@ -82,9 +83,12 @@ void add_associativity_ref_point(void)
> 	 * as a second level of NUMA.
> 	 *
> 	 * If there is a way to obtain this information from the FSP
>-	 * that would be ideal, but for now hardwire our POWER8E setting.
>+	 * that would be ideal, but for now hardwire our POWER8E, POWER8
>+	 * and POWER8NVL setting.
> 	 */
>-	if (PVR_TYPE(mfspr(SPR_PVR)) == PVR_TYPE_P8E)
>+	if (PVR_TYPE(pvr) == PVR_TYPE_P8E ||
>+	    PVR_TYPE(pvr) == PVR_TYPE_P8  ||
>+	    PVR_TYPE(pvr) == PVR_TYPE_P8NVL)
> 		ref2 = 0x3;
>
> 	dt_add_property_cells(opal_node, "ibm,associativity-reference-points",
>-- 
>2.7.4
>