[TG3]: Fix 5700/5701 DMA corruption on Apple G4.

Fix 5700/5701 DMA write corruption on Apple G4 by detecting the Apple
UniNorth PCI 1.5 chipset and adjusting the DMA write boundary to 16. DMA
test fails to detect the problem with this chipset.

Thanks to Manuel Perez Ayala for reporting the problem and helping to
debug it.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index e944aac258e3090c63b2c483bab9e28dd5cc872f..77337c3b42851695cb69086549d692a0a3e7e6f4 100644 (file)
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -9695,10 +9695,24 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
        }
        if ((tp->dma_rwctrl & DMA_RWCTRL_WRITE_BNDRY_MASK) !=
            DMA_RWCTRL_WRITE_BNDRY_16) {
+               static struct pci_device_id dma_wait_state_chipsets[] = {
+                       { PCI_DEVICE(PCI_VENDOR_ID_APPLE,
+                                    PCI_DEVICE_ID_APPLE_UNI_N_PCI15) },
+                       { },
+               };
+
                /* DMA test passed without adjusting DMA boundary,
-                * just restore the calculated DMA boundary
+                * now look for chipsets that are known to expose the
+                * DMA bug without failing the test.
                 */
-               tp->dma_rwctrl = saved_dma_rwctrl;
+               if (pci_dev_present(dma_wait_state_chipsets)) {
+                       tp->dma_rwctrl &= ~DMA_RWCTRL_WRITE_BNDRY_MASK;
+                       tp->dma_rwctrl |= DMA_RWCTRL_WRITE_BNDRY_16;
+               }
+               else
+                       /* Safe to use the calculated DMA boundary. */
+                       tp->dma_rwctrl = saved_dma_rwctrl;
+
                tw32(TG3PCI_DMA_RW_CTRL, tp->dma_rwctrl);
        }
 

diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index 18f734ec9181f9b30c0358a89284a0d5fa8e277e..b8b4ebf9abf1f3b28089030edcb067f4f08a080f 100644 (file)
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -874,6 +874,7 @@
 #define PCI_DEVICE_ID_APPLE_KL_USB_P   0x0026
 #define PCI_DEVICE_ID_APPLE_UNI_N_AGP_P        0x0027
 #define PCI_DEVICE_ID_APPLE_UNI_N_AGP15        0x002d
+#define PCI_DEVICE_ID_APPLE_UNI_N_PCI15        0x002e
 #define PCI_DEVICE_ID_APPLE_UNI_N_FW2  0x0030
 #define PCI_DEVICE_ID_APPLE_UNI_N_GMAC2        0x0032
 #define PCI_DEVIEC_ID_APPLE_UNI_N_ATA  0x0033