mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 15:02:32 +00:00
46 lines
1.7 KiB
Diff
46 lines
1.7 KiB
Diff
|
From 65b91d9a2af917b88d5381cd6a3d7bc92723c0f6 Mon Sep 17 00:00:00 2001
|
||
|
|
From: Joshua Emele <jemele@acm.org>
|
||
|
|
Date: Wed, 7 Nov 2018 16:07:40 -0800
|
||
|
|
Subject: [PATCH] lan78xx: Debounce link events to minimize poll storm
|
||
|
|
|
||
|
|
The bInterval is set to 4 (i.e. 8 microframes => 1ms) and the only bit
|
||
|
|
that the driver pays attention to is "link was reset". If there's a
|
||
|
|
flapping status bit in that endpoint data, (such as if PHY negotiation
|
||
|
|
needs a few tries to get a stable link) then polling at a slower rate
|
||
|
|
would act as a de-bounce.
|
||
|
|
|
||
|
|
See: https://github.com/raspberrypi/linux/issues/2447
|
||
|
|
---
|
||
|
|
drivers/net/usb/lan78xx.c | 13 ++++++++++++-
|
||
|
|
1 file changed, 12 insertions(+), 1 deletion(-)
|
||
|
|
|
||
|
|
--- a/drivers/net/usb/lan78xx.c
|
||
|
|
+++ b/drivers/net/usb/lan78xx.c
|
||
|
|
@@ -454,6 +454,11 @@ static bool enable_tso;
|
||
|
|
module_param(enable_tso, bool, 0644);
|
||
|
|
MODULE_PARM_DESC(enable_tso, "Enables TCP segmentation offload");
|
||
|
|
|
||
|
|
+#define INT_URB_MICROFRAMES_PER_MS 8
|
||
|
|
+static int int_urb_interval_ms = 8;
|
||
|
|
+module_param(int_urb_interval_ms, int, 0);
|
||
|
|
+MODULE_PARM_DESC(int_urb_interval_ms, "Override usb interrupt urb interval");
|
||
|
|
+
|
||
|
|
static int lan78xx_read_reg(struct lan78xx_net *dev, u32 index, u32 *data)
|
||
|
|
{
|
||
|
|
u32 *buf;
|
||
|
|
@@ -4148,7 +4153,13 @@ static int lan78xx_probe(struct usb_inte
|
||
|
|
netdev->max_mtu = MAX_SINGLE_PACKET_SIZE;
|
||
|
|
netif_set_gso_max_size(netdev, MAX_SINGLE_PACKET_SIZE - MAX_HEADER);
|
||
|
|
|
||
|
|
- period = ep_intr->desc.bInterval;
|
||
|
|
+ if (int_urb_interval_ms <= 0)
|
||
|
|
+ period = ep_intr->desc.bInterval;
|
||
|
|
+ else
|
||
|
|
+ period = int_urb_interval_ms * INT_URB_MICROFRAMES_PER_MS;
|
||
|
|
+
|
||
|
|
+ netif_notice(dev, probe, netdev, "int urb period %d\n", period);
|
||
|
|
+
|
||
|
|
maxp = usb_maxpacket(dev->udev, dev->pipe_intr, 0);
|
||
|
|
buf = kmalloc(maxp, GFP_KERNEL);
|
||
|
|
if (buf) {
|