[PATCH v3 05/10] net/fec: add dual fec support for mx28
Shawn Guo
shawn.guo at freescale.com
Wed Jan 5 23:14:59 EST 2011
Hi Uwe,
On Wed, Jan 05, 2011 at 05:34:49PM +0100, Uwe Kleine-König wrote:
> Hello,
>
> On Wed, Jan 05, 2011 at 10:07:32PM +0800, Shawn Guo wrote:
> > This patch is to add mx28 dual fec support. Here are some key notes
> > for mx28 fec controller.
> >
> > - The mx28 fec controller naming ENET-MAC is a different IP from FEC
> > used on other i.mx variants. But they are basically compatible
> > on software interface, so it's possible to share the same driver.
> > - ENET-MAC design made an improper assumption that it runs on a
> > big-endian system. As the result, driver has to swap every frame
> > going to and coming from the controller.
> > - The external phys can only be configured by fec0, which means fec1
> > can not work independently and both phys need to be configured by
> > mii_bus attached on fec0.
> > - ENET-MAC reset will get mac address registers reset too.
> > - ENET-MAC MII/RMII mode and 10M/100M speed are configured
> > differently FEC.
> > - ETHER_EN bit must be set to get ENET-MAC interrupt work.
> >
> > Signed-off-by: Shawn Guo <shawn.guo at freescale.com>
> > ---
> > Changes for v3:
> > - Move v2 changes into patch #3
> > - Use device name to check if it's running on ENET-MAC
> >
> > drivers/net/Kconfig | 7 ++-
> > drivers/net/fec.c | 140 +++++++++++++++++++++++++++++++++++++++++++++------
> > drivers/net/fec.h | 5 +-
> > 3 files changed, 131 insertions(+), 21 deletions(-)
> >
> > diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> > index 4f1755b..f34629b 100644
> > --- a/drivers/net/Kconfig
> > +++ b/drivers/net/Kconfig
> > @@ -1944,18 +1944,19 @@ config 68360_ENET
> > config FEC
> > bool "FEC ethernet controller (of ColdFire and some i.MX CPUs)"
> > depends on M523x || M527x || M5272 || M528x || M520x || M532x || \
> > - MACH_MX27 || ARCH_MX35 || ARCH_MX25 || ARCH_MX5
> > + MACH_MX27 || ARCH_MX35 || ARCH_MX25 || ARCH_MX5 || SOC_IMX28
> > select PHYLIB
> > help
> > Say Y here if you want to use the built-in 10/100 Fast ethernet
> > controller on some Motorola ColdFire and Freescale i.MX processors.
> >
> > config FEC2
> > - bool "Second FEC ethernet controller (on some ColdFire CPUs)"
> > + bool "Second FEC ethernet controller"
> > depends on FEC
> > help
> > Say Y here if you want to use the second built-in 10/100 Fast
> > - ethernet controller on some Motorola ColdFire processors.
> > + ethernet controller on some Motorola ColdFire and Freescale
> > + i.MX processors.
> >
> > config FEC_MPC52xx
> > tristate "MPC52xx FEC driver"
> > diff --git a/drivers/net/fec.c b/drivers/net/fec.c
> > index 8a1c51f..67ba263 100644
> > --- a/drivers/net/fec.c
> > +++ b/drivers/net/fec.c
> > @@ -17,6 +17,8 @@
> > *
> > * Bug fixes and cleanup by Philippe De Muyter (phdm at macqel.be)
> > * Copyright (c) 2004-2006 Macq Electronique SA.
> > + *
> > + * Copyright (C) 2010 Freescale Semiconductor, Inc.
> > */
> >
> > #include <linux/module.h>
> > @@ -45,20 +47,33 @@
> >
> > #include <asm/cacheflush.h>
> >
> > -#ifndef CONFIG_ARCH_MXC
> > +#if !defined(CONFIG_ARCH_MXC) && !defined(CONFIG_SOC_IMX28)
> maybe !defined(CONFIG_ARM)?
>
Sounds good.
> > #include <asm/coldfire.h>
> > #include <asm/mcfsim.h>
> > #endif
> >
> > #include "fec.h"
> >
> > -#ifdef CONFIG_ARCH_MXC
> > -#include <mach/hardware.h>
> > +#if defined(CONFIG_ARCH_MXC) || defined(CONFIG_SOC_IMX28)
> > #define FEC_ALIGNMENT 0xf
> > #else
> > #define FEC_ALIGNMENT 0x3
> > #endif
> >
> > +#define DRIVER_NAME "fec"
> > +#define ENET_MAC_NAME "enet-mac"
> > +
> > +static struct platform_device_id fec_devtype[] = {
> > + {
> > + .name = DRIVER_NAME,
> > + }, {
> > + .name = ENET_MAC_NAME,
> > + }
> I'd done it differently:
>
> {
> .name = "fec",
> .driver_data = 0,
> }, {
> .name = "imx28-fec",
> .driver_data = HAS_ENET_MAC | ...,
> }
>
> and then test the bits in driver_data (which you get using
> platform_get_device_id() when you need to distinguish.
> Comparing names doesn't scale, assume there are three further features
> to distinguish, then you need to use strtok or index and get device
> names like enet-mac-with-feature1-but-without-feature2-and-feature3.
>
Makes sense. The frame endian issue will be fixed in future revision,
so I would define bit SWAP_FRAME for testing.
> > +};
> > +
> > +static unsigned fec_is_enetmac;
> > +static struct mii_bus *fec_mii_bus;
> In practice this might work, but actually these are per-device
> properties, not driver-global. So it should go into the private data
> struct.
>
Since it's just a tmp variable for holding fec0 mii_bus in function
fec_enet_mii_init, I would move it into the function as a static
variable.
> > +
> > static unsigned char macaddr[ETH_ALEN];
> > module_param_array(macaddr, byte, NULL, 0);
> > MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");
> > @@ -129,7 +144,8 @@ MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");
> > * account when setting it.
> > */
> > #if defined(CONFIG_M523x) || defined(CONFIG_M527x) || defined(CONFIG_M528x) || \
> > - defined(CONFIG_M520x) || defined(CONFIG_M532x) || defined(CONFIG_ARCH_MXC)
> > + defined(CONFIG_M520x) || defined(CONFIG_M532x) || \
> > + defined(CONFIG_ARCH_MXC) || defined(CONFIG_SOC_IMX28)
> > #define OPT_FRAME_SIZE (PKT_MAXBUF_SIZE << 16)
> > #else
> > #define OPT_FRAME_SIZE 0
> > @@ -208,6 +224,17 @@ static void fec_stop(struct net_device *dev);
> > /* Transmitter timeout */
> > #define TX_TIMEOUT (2 * HZ)
> >
> > +static void *swap_buffer(void *bufaddr, int len)
> > +{
> > + int i;
> > + unsigned int *buf = bufaddr;
> > +
> > + for (i = 0; i < (len + 3) / 4; i++, buf++)
> > + *buf = __swab32(*buf);
> Would it better to use cpu_to_be32 here? Then the compiler might
> be smart enough to optimize it away on BE. (Currently the code
> generated for a BE build would be wrong with your patch, wouldn't it?)
Yes.
> > +
> > + return bufaddr;
> > +}
> > +
> > static netdev_tx_t
> > fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
> > {
> > @@ -256,6 +283,14 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
> > bufaddr = fep->tx_bounce[index];
> > }
> >
> > + /*
> > + * enet-mac design made an improper assumption that it's running
> > + * on a big endian system. As the result, driver has to swap
> if he was really aware that he limits the performant use of the fec to
> big endian systems, can you please make him stop designing hardware!?
>
You over looked my power :) BTW, he had left Freescale.
> > + * every frame going to and coming from the controller.
> > + */
> > + if (fec_is_enetmac)
> > + swap_buffer(bufaddr, skb->len);
> > +
> > /* Save skb pointer */
> > fep->tx_skbuff[fep->skb_cur] = skb;
> >
> > @@ -487,6 +522,9 @@ fec_enet_rx(struct net_device *dev)
> > dma_unmap_single(NULL, bdp->cbd_bufaddr, bdp->cbd_datlen,
> > DMA_FROM_DEVICE);
> >
> > + if (fec_is_enetmac)
> > + swap_buffer(data, pkt_len);
> > +
> > /* This does 16 byte alignment, exactly what we need.
> > * The packet length includes FCS, but we don't want to
> > * include that when passing upstream as it messes up
> > @@ -689,6 +727,7 @@ static int fec_enet_mii_probe(struct net_device *dev)
> > char mdio_bus_id[MII_BUS_ID_SIZE];
> > char phy_name[MII_BUS_ID_SIZE + 3];
> > int phy_id;
> > + int dev_id = fep->pdev->id;
> >
> > fep->phy_dev = NULL;
> >
> > @@ -700,6 +739,8 @@ static int fec_enet_mii_probe(struct net_device *dev)
> > continue;
> > if (fep->mii_bus->phy_map[phy_id]->phy_id == 0)
> > continue;
> > + if (fec_is_enetmac && dev_id--)
> > + continue;
> > strncpy(mdio_bus_id, fep->mii_bus->id, MII_BUS_ID_SIZE);
> > break;
> > }
> > @@ -741,6 +782,28 @@ static int fec_enet_mii_init(struct platform_device *pdev)
> > struct fec_enet_private *fep = netdev_priv(dev);
> > int err = -ENXIO, i;
> >
> > + /*
> > + * The dual fec interfaces are not equivalent with enet-mac.
> > + * Here are the differences:
> > + *
> > + * - fec0 supports MII & RMII modes while fec1 only supports RMII
> > + * - fec0 acts as the 1588 time master while fec1 is slave
> > + * - external phys can only be configured by fec0
> > + *
> > + * That is to say fec1 can not work independently. It only works
> > + * when fec0 is working. The reason behind this design is that the
> > + * second interface is added primarily for Switch mode.
> > + *
> > + * Because of the last point above, both phys are attached on fec0
> > + * mdio interface in board design, and need to be configured by
> > + * fec0 mii_bus.
> > + */
> > + if (fec_is_enetmac && pdev->id) {
> > + /* fec1 uses fec0 mii_bus */
> > + fep->mii_bus = fec_mii_bus;
> > + return 0;
> > + }
> > +
> > fep->mii_timeout = 0;
> >
> > /*
> > @@ -777,6 +840,10 @@ static int fec_enet_mii_init(struct platform_device *pdev)
> > if (mdiobus_register(fep->mii_bus))
> > goto err_out_free_mdio_irq;
> >
> > + /* save fec0 mii_bus */
> > + if (fec_is_enetmac)
> > + fec_mii_bus = fep->mii_bus;
> > +
> > return 0;
> >
> > err_out_free_mdio_irq:
> > @@ -1149,11 +1216,22 @@ fec_restart(struct net_device *dev, int duplex)
> > {
> > struct fec_enet_private *fep = netdev_priv(dev);
> > int i;
> > + u32 val, temp_mac[2];
> >
> > /* Whack a reset. We should wait for this. */
> > writel(1, fep->hwp + FEC_ECNTRL);
> > udelay(10);
> >
> > + /*
> > + * enet-mac reset will reset mac address registers too,
> > + * so need to reconfigure it.
> > + */
> > + if (fec_is_enetmac) {
> > + memcpy(&temp_mac, dev->dev_addr, ETH_ALEN);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > + writel(cpu_to_be32(temp_mac[0]), fep->hwp + FEC_ADDR_LOW);
> > + writel(cpu_to_be32(temp_mac[1]), fep->hwp + FEC_ADDR_HIGH);
> where is the value saved to temp_mac[]? For me it looks you write
> uninitialized data into the mac registers.
memcpy above.
--
Regards,
Shawn
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