Merge branch 'bugfix/eth_plus_wifi_doc_v5.2' into 'release/v5.2'

docs(esp_eth): added warning to not use ESP32 as ETH CLK source with WiFi (v5.2)

See merge request espressif/esp-idf!33246
This commit is contained in:
David Čermák 2024-09-12 14:35:15 +08:00
commit 95e16f6a72
4 changed files with 18 additions and 11 deletions

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@ -59,13 +59,11 @@ menu "Ethernet"
bool "Output RMII clock from GPIO0 (Experimental!)"
default n
help
GPIO0 can be set to output a pre-divided PLL clock (test only!).
Enabling this option will configure GPIO0 to output a 50MHz clock.
In fact this clock doesn't have directly relationship with EMAC peripheral.
Sometimes this clock won't work well with your PHY chip. You might need to
add some extra devices after GPIO0 (e.g. inverter).
Note that outputting RMII clock on GPIO0 is an experimental practice.
If you want the Ethernet to work with WiFi, don't select GPIO0 output mode for stability.
GPIO0 can be set to output a pre-divided PLL clock. Enabling this option will configure
GPIO0 to output a 50MHz clock. In fact this clock doesn't have directly relationship with
EMAC peripheral. Sometimes this clock may not work well with your PHY chip.
WARNING: If you want the Ethernet to work with WiFi, dont select ESP32 as RMII CLK output
as it would result in clock instability!
if !ETH_RMII_CLK_OUTPUT_GPIO0
config ETH_RMII_CLK_OUT_GPIO
@ -74,6 +72,8 @@ menu "Ethernet"
default 17
help
Set the GPIO number to output RMII Clock.
WARNING: If you want the Ethernet to work with WiFi, dont select ESP32 as RMII CLK output
as it would result in clock instability!
endif # !ETH_RMII_CLK_OUTPUT_GPIO0
endif # ETH_RMII_CLK_OUTPUT

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@ -349,6 +349,8 @@ typedef enum {
/**
* @brief RMII Clock GPIO number Options
*
* @warning If you want the Ethernet to work with WiFi, dont select ESP32 as RMII CLK output as it would result in clock instability.
*
*/
typedef enum {
/**
@ -362,10 +364,8 @@ typedef enum {
/**
* @brief Output RMII Clock from internal APLL Clock available at GPIO0
*
* @note GPIO0 can be set to output a pre-divided PLL clock (test only!). Enabling this option will configure GPIO0 to output a 50MHz clock.
* In fact this clock doesnt have directly relationship with EMAC peripheral. Sometimes this clock wont work well with your PHY chip.
* You might need to add some extra devices after GPIO0 (e.g. inverter). Note that outputting RMII clock on GPIO0 is an experimental practice.
* If you want the Ethernet to work with WiFi, dont select GPIO0 output mode for stability.
* @note GPIO0 can be set to output a pre-divided PLL clock. Enabling this option will configure GPIO0 to output a 50MHz clock.
* In fact this clock doesnt have directly relationship with EMAC peripheral. Sometimes this clock may not work well with your PHY chip.
*
*/
EMAC_APPL_CLK_OUT_GPIO = 0,

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@ -137,6 +137,9 @@ The Ethernet driver is composed of two parts: MAC and PHY.
* Force the PHY device to reset status (as the case **a** in the picture). **This could fail for some PHY device** (i.e., it still outputs signals to GPIO0 even in reset state).
.. warning::
If you want the **Ethernet to work with Wi-Fi**, dont select ESP32 as source of ``REF_CLK`` as it would result in ``REF_CLK`` instability. Either disable Wi-Fi or use a PHY or an external oscillator as the ``REF_CLK`` source.
**No matter which RMII clock mode you select, you really need to take care of the signal integrity of REF_CLK in your hardware design!** Keep the trace as short as possible. Keep it away from RF devices and inductor elements.
.. note::

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@ -142,6 +142,10 @@ ESP-IDF 提供一系列功能强大且兼具一致性的 API为内部以太
.. note::
ESP-IDF 只支持 RMII 接口(即在 Kconfig 选项 :ref:`CONFIG_ETH_PHY_INTERFACE` 中始终选择 ``CONFIG_ETH_PHY_INTERFACE_RMII``)。
.. warning::
如希望 **以太网与 Wi-Fi 一起工作**,不要选择 ESP32 作为 ``REF_CLK`` 的源,因为这会导致 ``REF_CLK`` 不稳定。可以选择禁用 Wi-Fi或使用 PHY 或外部振荡器作为 ``REF_CLK`` 的源。
在数据平面使用的信号通过 MUX 连接至特定的 GPIO这些信号无法配置至其他 GPIO。在控制平面使用的信号则可以通过 Matrix 矩阵路由到任何空闲 GPIO。相关的硬件设计示例请参考 `ESP32-Ethernet-Kit <https://docs.espressif.com/projects/esp-dev-kits/zh_CN/latest/esp32/esp32-ethernet-kit/index.html>`_
根据以太网板设计,需要分别为 MAC 和 PHY 配置必要的参数,通过两者完成驱动程序的安装。