+++ /dev/null
-From 6599df775e2cbb4988bdf8239acf4fbec70e5ef9 Mon Sep 17 00:00:00 2001
-From: Linus Walleij <linus.walleij@linaro.org>
-Date: Sat, 23 Sep 2023 20:38:22 +0200
-Subject: [PATCH 3/4] net: ixp4xx_eth: Support changing the MTU
-
-As we don't specify the MTU in the driver, the framework
-will fall back to 1500 bytes and this doesn't work very
-well when we try to attach a DSA switch:
-
- eth1: mtu greater than device maximum
- ixp4xx_eth c800a000.ethernet eth1: error -22 setting
- MTU to 1504 to include DSA overhead
-
-After locating an out-of-tree patch in OpenWrt I found
-suitable code to set the MTU on the interface and ported
-it and updated it. Now the MTU gets set properly.
-
-Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
-Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
----
- drivers/net/ethernet/xscale/ixp4xx_eth.c | 65 +++++++++++++++++++++++-
- 1 file changed, 64 insertions(+), 1 deletion(-)
-
---- a/drivers/net/ethernet/xscale/ixp4xx_eth.c
-+++ b/drivers/net/ethernet/xscale/ixp4xx_eth.c
-@@ -24,6 +24,7 @@
- #include <linux/dma-mapping.h>
- #include <linux/dmapool.h>
- #include <linux/etherdevice.h>
-+#include <linux/if_vlan.h>
- #include <linux/io.h>
- #include <linux/kernel.h>
- #include <linux/net_tstamp.h>
-@@ -63,7 +64,15 @@
-
- #define POOL_ALLOC_SIZE (sizeof(struct desc) * (RX_DESCS + TX_DESCS))
- #define REGS_SIZE 0x1000
--#define MAX_MRU 1536 /* 0x600 */
-+
-+/* MRU is said to be 14320 in a code dump, the SW manual says that
-+ * MRU/MTU is 16320 and includes VLAN and ethernet headers.
-+ * See "IXP400 Software Programmer's Guide" section 10.3.2, page 161.
-+ *
-+ * FIXME: we have chosen the safe default (14320) but if you can test
-+ * jumboframes, experiment with 16320 and see what happens!
-+ */
-+#define MAX_MRU (14320 - VLAN_ETH_HLEN)
- #define RX_BUFF_SIZE ALIGN((NET_IP_ALIGN) + MAX_MRU, 4)
-
- #define NAPI_WEIGHT 16
-@@ -1182,6 +1191,54 @@ static void destroy_queues(struct port *
- }
- }
-
-+static int ixp4xx_do_change_mtu(struct net_device *dev, int new_mtu)
-+{
-+ struct port *port = netdev_priv(dev);
-+ struct npe *npe = port->npe;
-+ int framesize, chunks;
-+ struct msg msg = {};
-+
-+ /* adjust for ethernet headers */
-+ framesize = new_mtu + VLAN_ETH_HLEN;
-+ /* max rx/tx 64 byte chunks */
-+ chunks = DIV_ROUND_UP(framesize, 64);
-+
-+ msg.cmd = NPE_SETMAXFRAMELENGTHS;
-+ msg.eth_id = port->id;
-+
-+ /* Firmware wants to know buffer size in 64 byte chunks */
-+ msg.byte2 = chunks << 8;
-+ msg.byte3 = chunks << 8;
-+
-+ msg.byte4 = msg.byte6 = framesize >> 8;
-+ msg.byte5 = msg.byte7 = framesize & 0xff;
-+
-+ if (npe_send_recv_message(npe, &msg, "ETH_SET_MAX_FRAME_LENGTH"))
-+ return -EIO;
-+ netdev_dbg(dev, "set MTU on NPE %s to %d bytes\n",
-+ npe_name(npe), new_mtu);
-+
-+ return 0;
-+}
-+
-+static int ixp4xx_eth_change_mtu(struct net_device *dev, int new_mtu)
-+{
-+ int ret;
-+
-+ /* MTU can only be changed when the interface is up. We also
-+ * set the MTU from dev->mtu when opening the device.
-+ */
-+ if (dev->flags & IFF_UP) {
-+ ret = ixp4xx_do_change_mtu(dev, new_mtu);
-+ if (ret < 0)
-+ return ret;
-+ }
-+
-+ dev->mtu = new_mtu;
-+
-+ return 0;
-+}
-+
- static int eth_open(struct net_device *dev)
- {
- struct port *port = netdev_priv(dev);
-@@ -1232,6 +1289,8 @@ static int eth_open(struct net_device *d
- if (npe_send_recv_message(port->npe, &msg, "ETH_SET_FIREWALL_MODE"))
- return -EIO;
-
-+ ixp4xx_do_change_mtu(dev, dev->mtu);
-+
- if ((err = request_queues(port)) != 0)
- return err;
-
-@@ -1374,6 +1433,7 @@ static int eth_close(struct net_device *
- static const struct net_device_ops ixp4xx_netdev_ops = {
- .ndo_open = eth_open,
- .ndo_stop = eth_close,
-+ .ndo_change_mtu = ixp4xx_eth_change_mtu,
- .ndo_start_xmit = eth_xmit,
- .ndo_set_rx_mode = eth_set_mcast_list,
- .ndo_eth_ioctl = eth_ioctl,
-@@ -1488,6 +1548,9 @@ static int ixp4xx_eth_probe(struct platf
- ndev->dev.dma_mask = dev->dma_mask;
- ndev->dev.coherent_dma_mask = dev->coherent_dma_mask;
-
-+ ndev->min_mtu = ETH_MIN_MTU;
-+ ndev->max_mtu = MAX_MRU;
-+
- netif_napi_add_weight(ndev, &port->napi, eth_poll, NAPI_WEIGHT);
-
- if (!(port->npe = npe_request(NPE_ID(port->id))))
projects / openwrt / staging / nbd.git / blobdiff