cxgb3 - Stop mac RX when changing MTU
Rx traffic needs to be halted when the MTU is changed
to avoid a potential chip hang.
Reset/restore MAC filters around a MTU change.
Also fix the pause frames high materwark setting.
Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/cxgb3/regs.h b/drivers/net/cxgb3/regs.h
index bf9d6be..020859c 100644
--- a/drivers/net/cxgb3/regs.h
+++ b/drivers/net/cxgb3/regs.h
@@ -1882,6 +1882,10 @@
#define V_COPYALLFRAMES(x) ((x) << S_COPYALLFRAMES)
#define F_COPYALLFRAMES V_COPYALLFRAMES(1U)
+#define S_DISBCAST 1
+#define V_DISBCAST(x) ((x) << S_DISBCAST)
+#define F_DISBCAST V_DISBCAST(1U)
+
#define A_XGM_RX_HASH_LOW 0x814
#define A_XGM_RX_HASH_HIGH 0x818
diff --git a/drivers/net/cxgb3/xgmac.c b/drivers/net/cxgb3/xgmac.c
index a506792..16cadba 100644
--- a/drivers/net/cxgb3/xgmac.c
+++ b/drivers/net/cxgb3/xgmac.c
@@ -231,6 +231,28 @@
return 0;
}
+static void disable_exact_filters(struct cmac *mac)
+{
+ unsigned int i, reg = mac->offset + A_XGM_RX_EXACT_MATCH_LOW_1;
+
+ for (i = 0; i < EXACT_ADDR_FILTERS; i++, reg += 8) {
+ u32 v = t3_read_reg(mac->adapter, reg);
+ t3_write_reg(mac->adapter, reg, v);
+ }
+ t3_read_reg(mac->adapter, A_XGM_RX_EXACT_MATCH_LOW_1); /* flush */
+}
+
+static void enable_exact_filters(struct cmac *mac)
+{
+ unsigned int i, reg = mac->offset + A_XGM_RX_EXACT_MATCH_HIGH_1;
+
+ for (i = 0; i < EXACT_ADDR_FILTERS; i++, reg += 8) {
+ u32 v = t3_read_reg(mac->adapter, reg);
+ t3_write_reg(mac->adapter, reg, v);
+ }
+ t3_read_reg(mac->adapter, A_XGM_RX_EXACT_MATCH_LOW_1); /* flush */
+}
+
/* Calculate the RX hash filter index of an Ethernet address */
static int hash_hw_addr(const u8 * addr)
{
@@ -281,6 +303,14 @@
return 0;
}
+static int rx_fifo_hwm(int mtu)
+{
+ int hwm;
+
+ hwm = max(MAC_RXFIFO_SIZE - 3 * mtu, (MAC_RXFIFO_SIZE * 38) / 100);
+ return min(hwm, MAC_RXFIFO_SIZE - 8192);
+}
+
int t3_mac_set_mtu(struct cmac *mac, unsigned int mtu)
{
int hwm, lwm;
@@ -306,11 +336,38 @@
lwm = min(3 * (int)mtu, MAC_RXFIFO_SIZE / 4);
v = t3_read_reg(adap, A_XGM_RXFIFO_CFG + mac->offset);
+ if (adap->params.rev == T3_REV_B2 &&
+ (t3_read_reg(adap, A_XGM_RX_CTRL + mac->offset) & F_RXEN)) {
+ disable_exact_filters(mac);
+ t3_set_reg_field(adap, A_XGM_RXFIFO_CFG + mac->offset,
+ F_ENHASHMCAST | F_COPYALLFRAMES, F_DISBCAST);
+
+ /* drain rx FIFO */
+ if (t3_wait_op_done(adap,
+ A_XGM_RX_MAX_PKT_SIZE_ERR_CNT +
+ mac->offset,
+ 1 << 31, 1, 20, 5)) {
+ t3_write_reg(adap, A_XGM_RXFIFO_CFG + mac->offset, v);
+ enable_exact_filters(mac);
+ return -EIO;
+ }
+ t3_write_reg(adap, A_XGM_RX_MAX_PKT_SIZE + mac->offset, mtu);
+ enable_exact_filters(mac);
+ } else
+ t3_write_reg(adap, A_XGM_RX_MAX_PKT_SIZE + mac->offset, mtu);
+
+ /*
+ * Adjust the PAUSE frame watermarks. We always set the LWM, and the
+ * HWM only if flow-control is enabled.
+ */
+ hwm = rx_fifo_hwm(mtu);
+ lwm = min(3 * (int)mtu, MAC_RXFIFO_SIZE / 4);
v &= ~V_RXFIFOPAUSELWM(M_RXFIFOPAUSELWM);
v |= V_RXFIFOPAUSELWM(lwm / 8);
if (G_RXFIFOPAUSEHWM(v))
v = (v & ~V_RXFIFOPAUSEHWM(M_RXFIFOPAUSEHWM)) |
V_RXFIFOPAUSEHWM(hwm / 8);
+
t3_write_reg(adap, A_XGM_RXFIFO_CFG + mac->offset, v);
/* Adjust the TX FIFO threshold based on the MTU */
@@ -329,7 +386,6 @@
(hwm - lwm) * 4 / 8);
t3_write_reg(adap, A_XGM_TX_PAUSE_QUANTA + mac->offset,
MAC_RXFIFO_SIZE * 4 * 8 / 512);
-
return 0;
}
@@ -357,6 +413,15 @@
V_PORTSPEED(M_PORTSPEED), val);
}
+ val = t3_read_reg(adap, A_XGM_RXFIFO_CFG + oft);
+ val &= ~V_RXFIFOPAUSEHWM(M_RXFIFOPAUSEHWM);
+ if (fc & PAUSE_TX)
+ val |= V_RXFIFOPAUSEHWM(rx_fifo_hwm(
+ t3_read_reg(adap,
+ A_XGM_RX_MAX_PKT_SIZE
+ + oft)) / 8);
+ t3_write_reg(adap, A_XGM_RXFIFO_CFG + oft, val);
+
t3_set_reg_field(adap, A_XGM_TX_CFG + oft, F_TXPAUSEEN,
(fc & PAUSE_RX) ? F_TXPAUSEEN : 0);
return 0;