Re: [PATCH v2 01/11] net: phy: Add rockchip phy driver support

From: Florian Fainelli
Date: Thu Jul 27 2017 - 12:51:42 EST


On 07/27/2017 05:55 AM, David Wu wrote:
> Support internal ephy currently.
>
> Signed-off-by: David Wu <david.wu@xxxxxxxxxxxxxx>
> ---
> changes in v2:
> - Alphabetic order for Kconfig and Makefile.
> - Add analog register init.
> - Disable auto-mdix for workround.
> - Rename config
>
> drivers/net/phy/Kconfig | 5 ++
> drivers/net/phy/Makefile | 1 +
> drivers/net/phy/rockchip.c | 128 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 134 insertions(+)
> create mode 100644 drivers/net/phy/rockchip.c
>
> diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
> index 2dda720..8dc6cd7 100644
> --- a/drivers/net/phy/Kconfig
> +++ b/drivers/net/phy/Kconfig
> @@ -334,6 +334,11 @@ config REALTEK_PHY
> ---help---
> Supports the Realtek 821x PHY.
>
> +config ROCKCHIP_PHY
> + tristate "Drivers for ROCKCHIP PHYs"

"Driver for Rockchip Ethernet PHYs" would seem more appropriate, this is
just one driver for now.

> + ---help---
> + Currently supports the internal ephy.

EPHY is usually how an Ethernet PHY is abbreviated.

> +
> config SMSC_PHY
> tristate "SMSC PHYs"
> ---help---
> diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
> index 8e9b9f3..350520e 100644
> --- a/drivers/net/phy/Makefile
> +++ b/drivers/net/phy/Makefile
> @@ -66,6 +66,7 @@ obj-$(CONFIG_MICROSEMI_PHY) += mscc.o
> obj-$(CONFIG_NATIONAL_PHY) += national.o
> obj-$(CONFIG_QSEMI_PHY) += qsemi.o
> obj-$(CONFIG_REALTEK_PHY) += realtek.o
> +obj-$(CONFIG_ROCKCHIP_PHY) += rockchip.o
> obj-$(CONFIG_SMSC_PHY) += smsc.o
> obj-$(CONFIG_STE10XP) += ste10Xp.o
> obj-$(CONFIG_TERANETICS_PHY) += teranetics.o
> diff --git a/drivers/net/phy/rockchip.c b/drivers/net/phy/rockchip.c
> new file mode 100644
> index 0000000..3f74658
> --- /dev/null
> +++ b/drivers/net/phy/rockchip.c
> @@ -0,0 +1,128 @@
> +/**
> + * drivers/net/phy/rockchip.c
> + *
> + * Driver for ROCKCHIP PHY
> + *
> + * Copyright (c) 2017, Fuzhou Rockchip Electronics Co., Ltd
> + *
> + * David Wu<david.wu@xxxxxxxxxxxxxx>

Missing space between your last name and your email address, there is
another typo like this in the MODULE_AUTHOR() macro.

> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mii.h>
> +#include <linux/ethtool.h>
> +#include <linux/phy.h>
> +#include <linux/netdevice.h>
> +
> +#define MII_INTERNAL_CTRL_STATUS 17
> +#define SMI_ADDR_TSTCNTL 20
> +#define SMI_ADDR_TSTREAD1 21
> +#define SMI_ADDR_TSTREAD2 22
> +#define SMI_ADDR_TSTWRITE 23
> +
> +#define AUTOMDIX_EN BIT(7)
> +#define TSTCNTL_RD (BIT(15) | BIT(10))
> +#define TSTCNTL_WR (BIT(14) | BIT(10))
> +
> +#define WR_ADDR_A7CFG 0x18
> +
> +static void rockchip_init_tstmode(struct phy_device *phydev)
> +{
> + /* Enable access to Analog and DSP register banks */
> + phy_write(phydev, SMI_ADDR_TSTCNTL, 0x0400);
> + phy_write(phydev, SMI_ADDR_TSTCNTL, 0x0000);
> + phy_write(phydev, SMI_ADDR_TSTCNTL, 0x0400);
> +}
> +
> +static void rockchip_close_tstmode(struct phy_device *phydev)
> +{
> + /* Back to basic register bank */
> + phy_write(phydev, SMI_ADDR_TSTCNTL, 0x0000);
> +}
> +
> +static void rockchip_internal_phy_analog_init(struct phy_device *phydev)
> +{
> + rockchip_init_tstmode(phydev);

Technically MDIO writes can fail, but you are not propagating the return
value, so you could be stuck on a bad page/bank.

> +
> + /*
> + * Adjust tx amplitude to make sginal better,
> + * the default value is 0x8.
> + */
> + phy_write(phydev, SMI_ADDR_TSTWRITE, 0xB);
> + phy_write(phydev, SMI_ADDR_TSTCNTL, TSTCNTL_WR | WR_ADDR_A7CFG);

Likewise.

> +
> + rockchip_close_tstmode(phydev);

Same here.

> +}
> +
> +static int rockchip_internal_phy_config_init(struct phy_device *phydev)
> +{
> + int val;
> +
> + /*
> + * The auto MIDX has linked problem on some board,
> + * workround to disable auto MDIX.
> + */

If this a board-specific problem you may consider register a PHY fixup
for the affected boards, or introduce a specific property to illustrate
that MDI-X is broken.

> + val = phy_read(phydev, MII_INTERNAL_CTRL_STATUS);
> + val &= ~AUTOMDIX_EN;
> + phy_write(phydev, MII_INTERNAL_CTRL_STATUS, val);

You also need to reject MDI configuration requests coming via
phy_ethtool_ksettings_set() which you should see in the
phyddrv::config_ane callback.

> +
> + rockchip_internal_phy_analog_init(phydev);
> +
> + return 0;
> +}
> +
> +static int rockchip_internal_phy_read_status(struct phy_device *phydev)
> +{
> + int ret, old_speed;
> +
> + old_speed = phydev->speed;
> + ret = genphy_read_status(phydev);
> + if (ret)
> + return ret;
> +
> + /*
> + * If mode switch happens from 10BT to 100BT, all DSP/AFE
> + * registers are set to default values. So any AFE/DSP
> + * registers have to be re-initialized in this case.
> + */
> + if ((old_speed == SPEED_10) && (phydev->speed == SPEED_100))
> + rockchip_internal_phy_analog_init(phydev);

link changes can be intercepted with a link_change_notify callback,
which would be more appropriate than doing this during read_status here.

> +
> + return ret;
> +}
> +
> +static struct phy_driver rockchip_phy_driver[] = {
> +{
> + .phy_id = 0x1234d400,
> + .phy_id_mask = 0xffff0000,

This mask is way too wide, the industry practice is to have the last 4
digits contain the PHY revision, so I would expect to see 0xffff_fff0
here as a mask.

> + .name = "rockchip internal ephy",

Rockchip internal EPHY?

> + .features = (PHY_BASIC_FEATURES | SUPPORTED_Pause
> + | SUPPORTED_Asym_Pause),
> + .soft_reset = genphy_soft_reset,

Since this is a driver for an internal PHY you also need:

.flags = PHY_IS_INTERNAL

> + .config_init = rockchip_internal_phy_config_init,
> + .config_aneg = genphy_config_aneg,
> + .read_status = rockchip_internal_phy_read_status,
> + .suspend = genphy_suspend,
> + .resume = genphy_resume,

You probably need your resume function to restore the AFE/DSP settings
that were done in rockchip_internal_phy_config_init()

> +},
> +};
> +
> +module_phy_driver(rockchip_phy_driver);
> +
> +static struct mdio_device_id __maybe_unused rockchip_phy_tbl[] = {
> + { 0x1234d400, 0xffff0000 },

Please also fix up the mask here.

> + { }
> +};
> +
> +MODULE_DEVICE_TABLE(mdio, rockchip_phy_tbl);
> +
> +MODULE_AUTHOR("David Wu<david.wu@xxxxxxxxxxxxxx>");

Typo here (same as in the heading).

> +MODULE_DESCRIPTION("Rockchip phy driver");

"Rockchip Ethernet PHY driver" so make it clear what type of PHY it manages?

> +MODULE_LICENSE("GPL v2");
>


--
Florian