[PATCH 12/12] atl1c: restore max-read-request-size in Device Conrol Register

From: xiong
Date: Wed Apr 18 2012 - 01:34:31 EST


in some platforms, we found the max-read-request-size in Device Control
Register is set to 0 by (BIOS?) during bootup, this will cause the
performance(throughput) very bad.
Restore it to a min-value.
register definition of REG_DEVICE_CTRL is removed, using kernel API to
access it as it's a standard pcie register.

Signed-off-by: xiong <xiong@xxxxxxxxxxxxxxxx>
Tested-by: Liu David <dwliu@xxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/atheros/atl1c/atl1c_hw.h | 6 +-----
drivers/net/ethernet/atheros/atl1c/atl1c_main.c | 16 ++++++++++------
2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_hw.h b/drivers/net/ethernet/atheros/atl1c/atl1c_hw.h
index a0b56ef..a37c82f 100644
--- a/drivers/net/ethernet/atheros/atl1c/atl1c_hw.h
+++ b/drivers/net/ethernet/atheros/atl1c/atl1c_hw.h
@@ -54,11 +54,7 @@ int atl1c_phy_power_saving(struct atl1c_hw *hw);
#define DEVICE_CAP_MAX_PAYLOAD_MASK 0x7
#define DEVICE_CAP_MAX_PAYLOAD_SHIFT 0

-#define REG_DEVICE_CTRL 0x60
-#define DEVICE_CTRL_MAX_PAYLOAD_MASK 0x7
-#define DEVICE_CTRL_MAX_PAYLOAD_SHIFT 5
-#define DEVICE_CTRL_MAX_RREQ_SZ_MASK 0x7
-#define DEVICE_CTRL_MAX_RREQ_SZ_SHIFT 12
+#define DEVICE_CTRL_MAXRRS_MIN 2

#define REG_LINK_CTRL 0x68
#define LINK_CTRL_L0S_EN 0x01
diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
index 8e737a5..b554004 100644
--- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
@@ -1045,19 +1045,23 @@ static void atl1c_configure_des_ring(struct atl1c_adapter *adapter)
static void atl1c_configure_tx(struct atl1c_adapter *adapter)
{
struct atl1c_hw *hw = &adapter->hw;
- u32 dev_ctrl_data;
- u32 max_pay_load;
+ int max_pay_load;
u16 tx_offload_thresh;
u32 txq_ctrl_data;

tx_offload_thresh = MAX_TX_OFFLOAD_THRESH;
AT_WRITE_REG(hw, REG_TX_TSO_OFFLOAD_THRESH,
(tx_offload_thresh >> 3) & TX_TSO_OFFLOAD_THRESH_MASK);
- AT_READ_REG(hw, REG_DEVICE_CTRL, &dev_ctrl_data);
- max_pay_load = (dev_ctrl_data >> DEVICE_CTRL_MAX_RREQ_SZ_SHIFT) &
- DEVICE_CTRL_MAX_RREQ_SZ_MASK;
+ max_pay_load = pcie_get_readrq(adapter->pdev) >> 8;
hw->dmar_block = min_t(u32, max_pay_load, hw->dmar_block);
-
+ /*
+ * if BIOS had changed the dam-read-max-length to an invalid value,
+ * restore it to default value
+ */
+ if (hw->dmar_block < DEVICE_CTRL_MAXRRS_MIN) {
+ pcie_set_readrq(adapter->pdev, 128 << DEVICE_CTRL_MAXRRS_MIN);
+ hw->dmar_block = DEVICE_CTRL_MAXRRS_MIN;
+ }
txq_ctrl_data =
hw->nic_type == athr_l2c_b || hw->nic_type == athr_l2c_b2 ?
L2CB_TXQ_CFGV : L1C_TXQ_CFGV;
--
1.7.7

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