diff options
| -rw-r--r-- | hw/xscom.c | 22 |
1 files changed, 21 insertions, 1 deletions
@@ -1,4 +1,4 @@ -/* Copyright 2013-2014 IBM Corp. +/* Copyright 2013-2017 IBM Corp. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -284,6 +284,16 @@ static int __xscom_read(uint32_t gcid, uint32_t pcb_addr, uint64_t *val) if (xscom_is_multicast_addr(pcb_addr) && ret == OPAL_XSCOM_CHIPLET_OFF) return ret; + /* + * Workaround on P9: PRD does operations it *knows* will fail with this + * error to work around a hardware issue where accesses via the PIB + * (FSI or OCC) work as expected, accesses via the ADU (what xscom goes + * through) do not. The chip logic will always return all FFs if there + * is any error on the scom. + */ + if (proc_gen == proc_gen_p9 && ret == OPAL_XSCOM_CHIPLET_OFF) + return ret; + prerror("XSCOM: Read failed, ret = %lld\n", ret); return ret; } @@ -324,6 +334,16 @@ static int __xscom_write(uint32_t gcid, uint32_t pcb_addr, uint64_t val) if (xscom_is_multicast_addr(pcb_addr) && ret == OPAL_XSCOM_CHIPLET_OFF) return ret; + /* + * Workaround on P9: PRD does operations it *knows* will fail with this + * error to work around a hardware issue where accesses via the PIB + * (FSI or OCC) work as expected, accesses via the ADU (what xscom goes + * through) do not. The chip logic will always return all FFs if there + * is any error on the scom. + */ + if (proc_gen == proc_gen_p9 && ret == OPAL_XSCOM_CHIPLET_OFF) + return ret; + prerror("XSCOM: Write failed, ret = %lld\n", ret); return ret; } |