[Skiboot] [PATCH] npu2-opencapi: don't fence on masked XSL errors

Frederic Barrat fbarrat at linux.ibm.com
Thu Dec 12 04:07:24 AEDT 2019

An upcoming change in the initfile is going to modify the default
action and fence behavior of some of the NPU FIR2 bits. We're already
overriding the settings of most of those. The one exception is for
bits 41 and 42, which are XSL errors impacting 2 links that we
mask (instead we rely on the subsequent OTL error, which is per link).

The new initfile will fence-on-error for bits 41 and 42. And even if
the FIRs are masked, the NPU logic could fence the links, which is not
what we want. So this patch makes sure we don't fence on the FIRs we
want to ignore. It has no effect on existing firmware.

Signed-off-by: Frederic Barrat <fbarrat at linux.ibm.com>
 hw/npu2-opencapi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/npu2-opencapi.c b/hw/npu2-opencapi.c
index ed6650f4..3b8b5976 100644
--- a/hw/npu2-opencapi.c
+++ b/hw/npu2-opencapi.c
@@ -1681,6 +1681,7 @@ static int enable_interrupts(struct npu2 *p)
 	reg = npu2_scom_read(p->chip_id, p->xscom_base, NPU2_MISC_FENCE_ENABLE2,
 	reg |= xstop_override;
+	reg &= ~(PPC_BIT(41) | PPC_BIT(42));
 	npu2_scom_write(p->chip_id, p->xscom_base, NPU2_MISC_FENCE_ENABLE2,
 			NPU2_MISC_DA_LEN_8B, reg);

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