Author: avg Date: Thu Nov 24 09:43:42 2016 New Revision: 309092 URL: https://svnweb.freebsd.org/changeset/base/309092
Log: fwohci: report whether PhysicalUpperBound register is implemented Please see section 5.15 of 1394 OHCI Specification. If the register is not implemented, then the physical response unit is limited to the first 4GB of the physical memory. In that case the non-cooperative debugging over firewire (using /dev/fwmem) can not be expected to work if a target has more RAM than that. The method is described in gdb.4 and the Developer's Handbook. It seems that most of the consumer hardware does not implement PhysicalUpperBound register. MFC after: 1 week Modified: head/sys/dev/firewire/fwohci.c Modified: head/sys/dev/firewire/fwohci.c ============================================================================== --- head/sys/dev/firewire/fwohci.c Thu Nov 24 09:39:00 2016 (r309091) +++ head/sys/dev/firewire/fwohci.c Thu Nov 24 09:43:42 2016 (r309092) @@ -1860,6 +1860,16 @@ fwohci_intr_core(struct fwohci_softc *sc prequpper = OHCI_PREQUPPER_MAX; } OWRITE(sc, OHCI_PREQUPPER, prequpper & 0xffffffff); + if (OREAD(sc, OHCI_PREQUPPER) != + (prequpper & 0xffffffff)) { + device_printf(fc->dev, + "PhysicalUpperBound register is not " + "implemented. Physical memory access " + "is limited to the first 4GB\n"); + device_printf(fc->dev, + "PhysicalUpperBound = 0x%08x\n", + OREAD(sc, OHCI_PREQUPPER)); + } } /* Set ATRetries register */ OWRITE(sc, OHCI_ATRETRY, 1<<(13 + 16) | 0xfff); _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"