[PATCH] chelsio: add MSI support
Using MSI can avoid sharing IRQ and associated overhead.
Tested on PCI-X.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/chelsio/common.h b/drivers/net/chelsio/common.h
index 55f1eaa..b265941 100644
--- a/drivers/net/chelsio/common.h
+++ b/drivers/net/chelsio/common.h
@@ -228,6 +228,7 @@
unsigned short chip_revision;
unsigned char chip_version;
unsigned char is_asic;
+ unsigned char has_msi;
};
struct link_config {
diff --git a/drivers/net/chelsio/cxgb2.c b/drivers/net/chelsio/cxgb2.c
index 571aa06..0ca5b07 100644
--- a/drivers/net/chelsio/cxgb2.c
+++ b/drivers/net/chelsio/cxgb2.c
@@ -107,6 +107,10 @@
module_param(t1powersave, int, 0);
MODULE_PARM_DESC(t1powersave, "Enable/Disable T1 powersaving mode");
+static int disable_msi = 0;
+module_param(disable_msi, int, 0);
+MODULE_PARM_DESC(disable_msi, "Disable Message Signaled Interrupt (MSI)");
+
static const char pci_speed[][4] = {
"33", "66", "100", "133"
};
@@ -215,11 +219,19 @@
}
t1_interrupts_clear(adapter);
- if ((err = request_irq(adapter->pdev->irq,
- t1_select_intr_handler(adapter), IRQF_SHARED,
- adapter->name, adapter))) {
+
+ adapter->params.has_msi = !disable_msi && pci_enable_msi(adapter->pdev) == 0;
+ err = request_irq(adapter->pdev->irq,
+ t1_select_intr_handler(adapter),
+ adapter->params.has_msi ? 0 : IRQF_SHARED,
+ adapter->name, adapter);
+ if (err) {
+ if (adapter->params.has_msi)
+ pci_disable_msi(adapter->pdev);
+
goto out_err;
}
+
t1_sge_start(adapter->sge);
t1_interrupts_enable(adapter);
out_err:
@@ -234,6 +246,8 @@
t1_sge_stop(adapter->sge);
t1_interrupts_disable(adapter);
free_irq(adapter->pdev->irq, adapter);
+ if (adapter->params.has_msi)
+ pci_disable_msi(adapter->pdev);
}
static int cxgb_open(struct net_device *dev)