From 4a815dc1eda7f4cf1868bea3f402a488c129c78e Mon Sep 17 00:00:00 2001 From: yongari Date: Mon, 10 Jan 2011 19:55:30 +0000 Subject: [PATCH] MFC r217226: Apply DMA address space restriction to controllers that have 4GB DMA boundary bug and runs with PCI-X mode. watchdog timeout was observed on BCM5704 which lives behind certain PCI-X bridge(e.g. AMD 8131 PCI-X bridge). It's still not clear whether the root cause came from that PCI-X bridge or not. The watchdog timeout indicates the issue is in TX path. If the bridge reorders TX mailbox write accesses it would generate all kinds of problems but I'm not sure. This should be revisited. Early MFC requested by re@ for inclusion in 8.2-RC2/7.4-RC2. Tested by: Michael L. Squires (mikes <> siralan dot org) Approved by: re (kensmith) git-svn-id: svn://svn.freebsd.org/base/releng/8.2@217233 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- sys/dev/bge/if_bge.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/sys/dev/bge/if_bge.c b/sys/dev/bge/if_bge.c index 09d790ec..0fb31734 100644 --- a/sys/dev/bge/if_bge.c +++ b/sys/dev/bge/if_bge.c @@ -2479,8 +2479,18 @@ bge_dma_alloc(struct bge_softc *sc) /* Create parent tag for buffers. */ boundary = 0; - if ((sc->bge_flags & BGE_FLAG_4G_BNDRY_BUG) != 0) + if ((sc->bge_flags & BGE_FLAG_4G_BNDRY_BUG) != 0) { boundary = BGE_DMA_BNDRY; + /* + * XXX + * watchdog timeout issue was observed on BCM5704 which + * lives behind PCI-X bridge(e.g AMD 8131 PCI-X bridge). + * Limiting DMA address space to 32bits seems to address + * it. + */ + if (sc->bge_flags & BGE_FLAG_PCIX) + lowaddr = BUS_SPACE_MAXADDR_32BIT; + } error = bus_dma_tag_create(bus_get_dma_tag(sc->bge_dev), 1, boundary, lowaddr, BUS_SPACE_MAXADDR, NULL, NULL, BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, -- 2.42.0