1 files changed, 19 insertions, 1 deletions

diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c
index 41b740aed3a3..69bd98421eb1 100644
--- a/drivers/parisc/lba_pci.c
+++ b/drivers/parisc/lba_pci.c
@@ -1403,9 +1403,27 @@ lba_hw_init(struct lba_device *d)
                 WRITE_REG32(stat, d->hba.base_addr + LBA_ERROR_CONFIG);
         }
 
-        /* Set HF mode as the default (vs. -1 mode). */
+
+        /*
+         * Hard Fail vs. Soft Fail on PCI "Master Abort".
+         *
+         * "Master Abort" means the MMIO transaction timed out - usually due to
+         * the device not responding to an MMIO read. We would like HF to be
+         * enabled to find driver problems, though it means the system will
+         * crash with a HPMC.
+         *
+         * In SoftFail mode "~0L" is returned as a result of a timeout on the
+         * pci bus. This is like how PCI busses on x86 and most other
+         * architectures behave.  In order to increase compatibility with
+         * existing (x86) PCI hardware and existing Linux drivers we enable
+         * Soft Faul mode on PA-RISC now too.
+         */
         stat = READ_REG32(d->hba.base_addr + LBA_STAT_CTL);
+#if defined(ENABLE_HARDFAIL)
         WRITE_REG32(stat | HF_ENABLE, d->hba.base_addr + LBA_STAT_CTL);
+#else
+        WRITE_REG32(stat & ~HF_ENABLE, d->hba.base_addr + LBA_STAT_CTL);
+#endif
 
         /*
         ** Writing a zero to STAT_CTL.rf (bit 0) will clear reset signal