kernel: add bgmac fixes for various issues

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 45388

1 files changed, 87 insertions, 0 deletions

diff --git a/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch b/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch
new file mode 100644
index 0000000000..79746540c9
--- /dev/null
+++ b/target/linux/generic/patches-3.18/077-05-bgmac-leave-interrupts-disabled-as-long-as-there-is-.patch
@@ -0,0 +1,87 @@
+From: Felix Fietkau <nbd@openwrt.org>
+Date: Sun, 12 Apr 2015 10:08:04 +0200
+Subject: [PATCH] bgmac: leave interrupts disabled as long as there is work
+ to do
+
+Always poll rx and tx during NAPI poll instead of relying on the status
+of the first interrupt. This prevents bgmac_poll from leaving unfinished
+work around until the next IRQ.
+In my tests this makes bridging/routing throughput under heavy load more
+stable and ensures that no new IRQs arrive as long as bgmac_poll uses up
+the entire budget.
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+---
+
+--- a/drivers/net/ethernet/broadcom/bgmac.c
++++ b/drivers/net/ethernet/broadcom/bgmac.c
+@@ -1105,8 +1105,6 @@ static void bgmac_chip_reset(struct bgma
+ 	bgmac_phy_init(bgmac);
+ 
+ 	netdev_reset_queue(bgmac->net_dev);
+-
+-	bgmac->int_status = 0;
+ }
+ 
+ static void bgmac_chip_intrs_on(struct bgmac *bgmac)
+@@ -1221,14 +1219,13 @@ static irqreturn_t bgmac_interrupt(int i
+ 	if (!int_status)
+ 		return IRQ_NONE;
+ 
+-	/* Ack */
+-	bgmac_write(bgmac, BGMAC_INT_STATUS, int_status);
++	int_status &= ~(BGMAC_IS_TX0 | BGMAC_IS_RX);
++	if (int_status)
++		bgmac_err(bgmac, "Unknown IRQs: 0x%08X\n", int_status);
+ 
+ 	/* Disable new interrupts until handling existing ones */
+ 	bgmac_chip_intrs_off(bgmac);
+ 
+-	bgmac->int_status = int_status;
+-
+ 	napi_schedule(&bgmac->napi);
+ 
+ 	return IRQ_HANDLED;
+@@ -1237,25 +1234,17 @@ static irqreturn_t bgmac_interrupt(int i
+ static int bgmac_poll(struct napi_struct *napi, int weight)
+ {
+ 	struct bgmac *bgmac = container_of(napi, struct bgmac, napi);
+-	struct bgmac_dma_ring *ring;
+ 	int handled = 0;
+ 
+-	if (bgmac->int_status & BGMAC_IS_TX0) {
+-		ring = &bgmac->tx_ring[0];
+-		bgmac_dma_tx_free(bgmac, ring);
+-		bgmac->int_status &= ~BGMAC_IS_TX0;
+-	}
++	/* Ack */
++	bgmac_write(bgmac, BGMAC_INT_STATUS, ~0);
+ 
+-	if (bgmac->int_status & BGMAC_IS_RX) {
+-		ring = &bgmac->rx_ring[0];
+-		handled += bgmac_dma_rx_read(bgmac, ring, weight);
+-		bgmac->int_status &= ~BGMAC_IS_RX;
+-	}
++	bgmac_dma_tx_free(bgmac, &bgmac->tx_ring[0]);
++	handled += bgmac_dma_rx_read(bgmac, &bgmac->rx_ring[0], weight);
+ 
+-	if (bgmac->int_status) {
+-		bgmac_err(bgmac, "Unknown IRQs: 0x%08X\n", bgmac->int_status);
+-		bgmac->int_status = 0;
+-	}
++	/* poll again if more events arrived in the mean time */
++	if (bgmac_read(bgmac, BGMAC_INT_STATUS) & (BGMAC_IS_TX0 | BGMAC_IS_RX))
++		return handled;
+ 
+ 	if (handled < weight) {
+ 		napi_complete(napi);
+--- a/drivers/net/ethernet/broadcom/bgmac.h
++++ b/drivers/net/ethernet/broadcom/bgmac.h
+@@ -452,7 +452,6 @@ struct bgmac {
+ 
+ 	/* Int */
+ 	u32 int_mask;
+-	u32 int_status;
+ 
+ 	/* Current MAC state */
+ 	int mac_speed;