From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Mon, 2 Jul 2012 08:20:05 +0000 (+0800)
Subject: bge: Workaround mbox write reordering for PCI-X devices
X-Git-Tag: v3.2.0~705
X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/e8b8fe834af9a19b1be50e90a51cc49735a699b3

bge: Workaround mbox write reordering for PCI-X devices

Add per device tunable hw.bgeX.mbox_reorder to control this; it is
off by default.

Based-on: FreeBSD 232848
---

diff --git a/sys/dev/netif/bge/if_bge.c b/sys/dev/netif/bge/if_bge.c
index 56cc5895aa..c99ffef433 100644
--- a/sys/dev/netif/bge/if_bge.c
+++ b/sys/dev/netif/bge/if_bge.c
@@ -497,6 +497,8 @@ bge_writembx(struct bge_softc *sc, int off, int val)
 		off += BGE_LPMBX_IRQ0_HI - BGE_MBX_IRQ0_HI;
 
 	CSR_WRITE_4(sc, off, val);
+	if (sc->bge_mbox_reorder)
+		CSR_READ_4(sc, off);
 }
 
 static uint8_t
@@ -2155,6 +2157,8 @@ bge_attach(device_t dev)
 		    BGE_PCISTATE_PCI_BUSMODE) == 0) {
 			sc->bge_flags |= BGE_FLAG_PCIX;
 			sc->bge_pcixcap = pci_get_pcixcap_ptr(sc->bge_dev);
+			sc->bge_mbox_reorder = device_getenv_int(sc->bge_dev,
+			    "mbox_reorder", 0);
 		}
  	}
 
diff --git a/sys/dev/netif/bge/if_bgereg.h b/sys/dev/netif/bge/if_bgereg.h
index 43fc2a910c..4d585f8624 100644
--- a/sys/dev/netif/bge/if_bgereg.h
+++ b/sys/dev/netif/bge/if_bgereg.h
@@ -2553,6 +2553,7 @@ struct bge_softc {
 	uint32_t		bge_tx_buf_ratio;
 	uint32_t		bge_mi_mode;
 	int			bge_force_defrag;
+	int			bge_mbox_reorder;
 	int			bge_if_flags;
 	int			bge_txcnt;
 	int			bge_link;