[PATCH v5 6/8] net: pch_gbe: Add PHY reset and MAC address fallback for RISC-V

[Uros Stajic]

Hi Leo,

On 3/17/26 09:49, Leo Liang wrote:
> On Wed, Dec 24, 2025 at 03:47:02PM +0000, Uros Stajic wrote:
>> From: Chao-ying Fu <cfu at mips.com>
>>
>> Add optional PHY reset support via GPIO defined in the device tree.
>>
>> Improve robustness by handling probe errors and falling back to the
>> environment-provided MAC address if no hardware MAC is found.
>>
>> Signed-off-by: Chao-ying Fu <cfu at mips.com>
>> Signed-off-by: Uros Stajic <uros.stajic at htecgroup.com>
>> ---
>>   board/mips/boston-riscv/Kconfig |  4 ++++
>>   drivers/net/pch_gbe.c           | 37 +++++++++++++++++++++++++++++++--
>>   drivers/net/pch_gbe.h           |  1 +
>>   3 files changed, 40 insertions(+), 2 deletions(-)
>>
>> diff --git a/board/mips/boston-riscv/Kconfig b/board/mips/boston-riscv/Kconfig
>> index 68c5fc50489..4d55d96603e 100644
>> --- a/board/mips/boston-riscv/Kconfig
>> +++ b/board/mips/boston-riscv/Kconfig
>> @@ -40,4 +40,8 @@ config PHY_REALTEK
>>       bool
>>       default y
>>
>> +config TFTP_FILE_NAME_MAX_LEN
>> +    int "Maximum length of TFTP file name"
>> +    default 256
>> +
>>   endif
>> diff --git a/drivers/net/pch_gbe.c b/drivers/net/pch_gbe.c
>> index adeca3d040d..dea8ab828ac 100644
>> --- a/drivers/net/pch_gbe.c
>> +++ b/drivers/net/pch_gbe.c
>> @@ -7,6 +7,7 @@
>>
>>   #include <cpu_func.h>
>>   #include <dm.h>
>> +#include <env.h>
>>   #include <errno.h>
>>   #include <log.h>
>>   #include <malloc.h>
>> @@ -15,6 +16,7 @@
>>   #include <miiphy.h>
>>   #include <linux/delay.h>
>>   #include "pch_gbe.h"
>> +#include <asm/gpio.h>
> 
> This should be <asm-generic/gpio.h>, right?
> 

Thanks, you're right. I'll switch it to <asm-generic/gpio.h> in the next 
revision.

>>
>>   #if !defined(CONFIG_PHYLIB)
>>   # error "PCH Gigabit Ethernet driver requires PHYLIB - missing CONFIG_PHYLIB"
>> @@ -33,6 +35,13 @@ static void pch_gbe_mac_read(struct pch_gbe_regs *mac_regs, u8 *addr)
>>        macid_lo = readl(&mac_regs->mac_adr[0].low) & 0xffff;
>>        debug("pch_gbe: macid_hi %#x macid_lo %#x\n", macid_hi, macid_lo);
>>
>> +     if (!macid_lo && !macid_hi) {
>> +             if (eth_env_get_enetaddr("ethaddr", addr))
>> +                     return;
>> +
>> +             printf("No MAC found in either EG20T H/W or environment");
>> +     }
>> +
>>        addr[0] = (u8)(macid_hi & 0xff);
>>        addr[1] = (u8)((macid_hi >> 8) & 0xff);
>>        addr[2] = (u8)((macid_hi >> 16) & 0xff);
>> @@ -74,6 +83,14 @@ static int pch_gbe_reset(struct udevice *dev)
>>        priv->rx_idx = 0;
>>        priv->tx_idx = 0;
>>
>> +     if (dm_gpio_is_valid(&priv->gpio_phy_reset)) {
>> +             /* Reset the PHY */
>> +             dm_gpio_set_value(&priv->gpio_phy_reset, 1);
>> +             udelay(15000);
>> +             dm_gpio_set_value(&priv->gpio_phy_reset, 0);
>> +             udelay(5000);
>> +     }
>> +
>>        writel(PCH_GBE_ALL_RST, &mac_regs->reset);
>>
>>        /*
>> @@ -450,6 +467,11 @@ static int pch_gbe_probe(struct udevice *dev)
>>        plat->iobase = (ulong)iobase;
>>        priv->mac_regs = (struct pch_gbe_regs *)iobase;
>>
>> +     err = gpio_request_by_name(dev, "phy-reset-gpios", 0,
>> +                                &priv->gpio_phy_reset, GPIOD_IS_OUT);
>> +     if (err && (err != -ENOENT))
>> +             return err;
>> +
>>        /* Read MAC address from SROM and initialize dev->enetaddr with it */
>>        pch_gbe_mac_read(priv->mac_regs, plat->enetaddr);
>>
>> @@ -459,9 +481,17 @@ static int pch_gbe_probe(struct udevice *dev)
>>
>>        err = pch_gbe_reset(dev);
>>        if (err)
>> -             return err;
>> +             goto out_err;
>> +
>> +     err = pch_gbe_phy_init(dev);
>> +     if (err)
>> +             goto out_err;
>>
>> -     return pch_gbe_phy_init(dev);
>> +     return 0;
>> +out_err:
>> +     if (dm_gpio_is_valid(&priv->gpio_phy_reset))
>> +             dm_gpio_free(dev, &priv->gpio_phy_reset);
>> +     return err;
>>   }
>>
>>   static int pch_gbe_remove(struct udevice *dev)
>> @@ -472,6 +502,9 @@ static int pch_gbe_remove(struct udevice *dev)
>>        mdio_unregister(priv->bus);
>>        mdio_free(priv->bus);
>>
>> +     if (dm_gpio_is_valid(&priv->gpio_phy_reset))
>> +             dm_gpio_free(dev, &priv->gpio_phy_reset);
>> +
>>        return 0;
>>   }
>>
>> diff --git a/drivers/net/pch_gbe.h b/drivers/net/pch_gbe.h
>> index 7e0fdbfd5a3..dcbb94094bc 100644
>> --- a/drivers/net/pch_gbe.h
>> +++ b/drivers/net/pch_gbe.h
>> @@ -292,6 +292,7 @@ struct pch_gbe_priv {
>>        struct udevice *dev;
>>        int rx_idx;
>>        int tx_idx;
>> +     struct gpio_desc gpio_phy_reset;
>>   };
>>
>>   #endif /* _PCH_GBE_H_ */

Best regards,
Uros