Re: [RESEND PATCH v2 02/11] net: dwc_eth_qos: Add option "snps,reset-gpio" phy-rst gpio for stm32

[David Wu]

Hi Patrick,

Yes, this is the case, it should be add at PHY node, and I also used the 
original writing "snps,reset*" at MAC node. Anyway, I will try to put 
the reset gpio in the PHY node.

在 2020/5/13 下午8:55, Patrick DELAUNAY 写道:
Hi David

From: David Wu <david...@rock-chips.com>
Sent: mardi 12 mai 2020 11:56

It can be seen that most of the Socs using STM mac, "snps,reset-gpio"
gpio is used, adding this option makes reset function more general.

Signed-off-by: David Wu <david...@rock-chips.com>
---

Changes in v2:
- Remove the code is not related (Patrice)

  drivers/net/dwc_eth_qos.c | 32 +++++++++++++++++++++++++++++++-
  1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c index
66a02aa80b..92dab678c7 100644
--- a/drivers/net/dwc_eth_qos.c
+++ b/drivers/net/dwc_eth_qos.c
@@ -314,6 +314,7 @@ struct eqos_priv {
        struct eqos_tegra186_regs *tegra186_regs;
        struct reset_ctl reset_ctl;
        struct gpio_desc phy_reset_gpio;
+       u32 reset_delays[3];
        struct clk clk_master_bus;
        struct clk clk_rx;
        struct clk clk_ptp_ref;
@@ -739,6 +740,15 @@ static int eqos_start_resets_stm32(struct udevice *dev)

        debug("%s(dev=%p):\n", __func__, dev);
        if (dm_gpio_is_valid(&eqos->phy_reset_gpio)) {
+               ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 0);
+               if (ret < 0) {
+                       pr_err("dm_gpio_set_value(phy_reset, deassert) failed:
%d",
+                              ret);
+                       return ret;
+               }
+
+               udelay(eqos->reset_delays[0]);
+
                ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 1);
                if (ret < 0) {
                        pr_err("dm_gpio_set_value(phy_reset, assert) failed: 
%d",
@@ -746,7 +756,7 @@ static int eqos_start_resets_stm32(struct udevice *dev)
                        return ret;
                }

-               udelay(2);
+               udelay(eqos->reset_delays[1]);

                ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 0);
                if (ret < 0) {
@@ -754,6 +764,8 @@ static int eqos_start_resets_stm32(struct udevice *dev)
                               ret);
                        return ret;
                }
+
+               udelay(eqos->reset_delays[2]);
        }
        debug("%s: OK\n", __func__);

@@ -1864,11 +1876,29 @@ static int eqos_probe_resources_stm32(struct
udevice *dev)
                if (ret)
                        pr_warn("gpio_request_by_name(phy reset) not provided
%d",
                                ret);
+               else
+                       eqos->reset_delays[1] = 2;

                eqos->phyaddr = ofnode_read_u32_default(phandle_args.node,
                                                        "reg", -1);
        }

+       if (!dm_gpio_is_valid(&eqos->phy_reset_gpio)) {
+               int reset_flags = GPIOD_IS_OUT;
+
+               if (dev_read_bool(dev, "snps,reset-active-low"))
+                       reset_flags |= GPIOD_ACTIVE_LOW;
+
+               ret = gpio_request_by_name(dev, "snps,reset-gpio", 0,
+                                          &eqos->phy_reset_gpio, reset_flags);
+               if (ret == 0)
+                       ret = dev_read_u32_array(dev, "snps,reset-delays-us",
+                                                eqos->reset_delays, 3);
+               else
+                       pr_warn("gpio_request_by_name(snps,reset-gpio) failed:
%d",
+                               ret);
+       }
+
        debug("%s: OK\n", __func__);
        return 0;

--
2.19.1



This obsolete binding isn't expected to be supported in stm32 glue for dwmac
(and it tis the purpose of eqos_stm32_config)

Reference in linux binding
./Documentation/devicetree/bindings/net/stm32-dwmac.txt (the glue)
./Documentation/devicetree/bindings/net/snps,dwmac.yaml

   snps,reset-gpio:
     deprecated: true

   snps,reset-active-low:
     deprecated: true

   snps,reset-delays-us:
     deprecated: true

I expected that gpio reset in future device tree should be managed by only by 
PHY generic binding
(upstream in progress on Linux side for STM32MP15x), as described in:

Documentation/devicetree/bindings/net/ethernet-phy.yaml

   reset-gpios:
     maxItems: 1
     description:
       The GPIO phandle and specifier for the PHY reset signal.

   reset-assert-us:
     description:
       Delay after the reset was asserted in microseconds. If this
       property is missing the delay will be skipped.

   reset-deassert-us:
     description:
       Delay after the reset was deasserted in microseconds. If
       this property is missing the delay will be skipped.

See alsoU-Boot: doc/device-tree-bindings/net/phy.txt

Something as

&mac {
        status = "okay";
        pinctrl-0       = <&ethernet_mii>;
        pinctrl-names   = "default";
        phy-mode        = "mii";
        phy-handle      = <&phy1>;
        mdio0 {
                #address-cells = <1>;
                #size-cells = <0>;
                compatible = "snps,dwmac-mdio";
                phy1: ethernet-phy@1 {
                        reg = <1>;
+                       reset-assert-us = <10000>;
+                       reset-deassert-us = <30000>;
+                       reset-gpios = <&gpioh 15 GPIO_ACTIVE_LOW>;
                };
        };
};

And this binding "reset-gpios" is supported since the commit 5177b31ba6aa
("net: dwc_eth_qos: implement reset-gpios for stm32")

"reset-assert-us" and "reset-deassert-us" can be added if needed.

For witch product / compatible do you want add the support of this obsolete 
binding ?

Regards

Patrick