diff options
| -rw-r--r-- | drivers/pcmcia/topic.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/pcmcia/topic.h b/drivers/pcmcia/topic.h index 615a45a8fe86..582688fe7505 100644 --- a/drivers/pcmcia/topic.h +++ b/drivers/pcmcia/topic.h @@ -104,6 +104,9 @@ #define TOPIC_EXCA_IF_CONTROL 0x3e /* 8 bit */ #define TOPIC_EXCA_IFC_33V_ENA 0x01 +#define TOPIC_PCI_CFG_PPBCN 0x3e /* 16-bit */ +#define TOPIC_PCI_CFG_PPBCN_WBEN 0x0400 + static void topic97_zoom_video(struct pcmcia_socket *sock, int onoff) { struct yenta_socket *socket = container_of(sock, struct yenta_socket, socket); @@ -138,6 +141,7 @@ static int topic97_override(struct yenta_socket *socket) static int topic95_override(struct yenta_socket *socket) { u8 fctrl; + u16 ppbcn; /* enable 3.3V support for 16bit cards */ fctrl = exca_readb(socket, TOPIC_EXCA_IF_CONTROL); @@ -146,6 +150,18 @@ static int topic95_override(struct yenta_socket *socket) /* tell yenta to use exca registers to power 16bit cards */ socket->flags |= YENTA_16BIT_POWER_EXCA | YENTA_16BIT_POWER_DF; + /* Disable write buffers to prevent lockups under load with numerous + Cardbus cards, observed on Tecra 500CDT and reported elsewhere on the + net. This is not a power-on default according to the datasheet + but some BIOSes seem to set it. */ + if (pci_read_config_word(socket->dev, TOPIC_PCI_CFG_PPBCN, &ppbcn) == 0 + && socket->dev->revision <= 7 + && (ppbcn & TOPIC_PCI_CFG_PPBCN_WBEN)) { + ppbcn &= ~TOPIC_PCI_CFG_PPBCN_WBEN; + pci_write_config_word(socket->dev, TOPIC_PCI_CFG_PPBCN, ppbcn); + dev_info(&socket->dev->dev, "Disabled ToPIC95 Cardbus write buffers.\n"); + } + return 0; } |