boards: st: stm32h7s78_dk: add Ethernet support

Add Ethernet configuration for mac and mdio nodes.
Define the SRAM region for Ethernet descriptor and buffer
using memory-regions = <...> in the mac node for this board
and for nucleo_h7s3l8, since they both use the same
mpu_regions.c and sections.ld files.

Add memory-regions property to st,stm32h7-ethernet.yaml file.

Update mpu_regions.c and sections.ld to use the region defined
in board's .dtsi file. Add an assert to mpu_regions.c to check
if the memory-region node refers to the zephyr,sram region.

Disable mac node in .overlay files for tests/drivers/memc/ram
since ethernet drivers that get enabled by it consume sram1
node and thus fail the test.

Update the yaml files to include Ethernet tag and
update documentation to explain Ethernet usage.

Signed-off-by: Benjamin Klaric <benjamin.klaric01@gmail.com>

Author: bklaric1

boards/st/nucleo_h7s3l8/nucleo_h7s3l8.dts

@@ -181,6 +181,7 @@
 	pinctrl-names = "default";
 	phy-connection-type = "rmii";
 	phy-handle = <&eth_phy>;
+	memory-regions = <&sram1>;
 	status = "okay";
 };
 

boards/st/stm32h7s78_dk/doc/index.rst

@@ -181,6 +181,7 @@ Default Zephyr Peripheral Mapping:
 - XSPI1 NCS/DQS0/DQS1/CLK/IO: PO0/PO2/PO3/PO4/PP0..15
 - I2C1 SCL/SDA: PB6/PB9
 - FDCAN1 RX/TX : PB8/PB9
+- ETH: PA2/PA7/PB0/PB1/PC1/PC4/PC5/PD7/PG11
 
 System Clock
 ------------
@@ -208,6 +209,12 @@ STM32H7S78-DK Discovery board has 2 FDCAN bus interfaces.
 FDCAN1 is configured but not enabled by default. To enable it, make sure
 that ``i2c1`` is disabled, since they share the PB9 pin.
 
+Ethernet
+--------
+
+In order to use Ethernet on STM32H7S78-DK, you need to set the ``JP6`` jumper
+to PC1 position on the back side of the board.
+
 Programming and Debugging
 *************************
 

boards/st/stm32h7s78_dk/stm32h7s78_dk-common.dtsi

@@ -11,6 +11,11 @@
 #include "zephyr/dt-bindings/display/panel.h"
 #include <zephyr/dt-bindings/input/input-event-codes.h>
 
+/*
+ * WARNING:
+ * JP6 must be in PC1 position when using Ethernet.
+ */
+
 / {
 	chosen {
 		zephyr,console = &uart4;
@@ -228,6 +233,32 @@
 	status = "disabled";
 };
 
+&mac {
+	pinctrl-0 = <&eth_rmii_ref_clk_pd7
+		     &eth_rmii_crs_dv_pa7
+		     &eth_rmii_rxd0_pc4
+		     &eth_rmii_rxd1_pc5
+		     &eth_rmii_tx_en_pg11
+		     &eth_rmii_txd0_pb0
+		     &eth_rmii_txd1_pb1>;
+	pinctrl-names = "default";
+	phy-connection-type = "rmii";
+	phy-handle = <&eth_phy>;
+	memory-regions = <&sram1>;
+	status = "okay";
+};
+
+&mdio {
+	pinctrl-0 = <&eth_mdio_pa2 &eth_mdc_pc1>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	eth_phy: ethernet-phy@0 {
+		compatible = "ethernet-phy";
+		reg = <0x00>;
+	};
+};
+
 &xspi1 {
 	pinctrl-0 = <&xspim_p1_ncs1_po0 &xspim_p1_dqs0_po2
 		     &xspim_p1_dqs1_po3 &xspim_p1_clk_po4

boards/st/stm32h7s78_dk/stm32h7s78_dk.yaml

@@ -16,4 +16,5 @@ supported:
   - octospi
   - usbd
   - memc
+  - netif:eth
 vendor: st

boards/st/stm32h7s78_dk/stm32h7s78_dk_stm32h7s7xx_ext_flash_app.yaml

@@ -17,4 +17,5 @@ supported:
   - octospi
   - usbd
   - memc
+  - netif:eth
 vendor: st

dts/arm/st/h7rs/stm32h7rs.dtsi

@@ -54,13 +54,15 @@
 		reg = <0x24000000 DT_SIZE_K(456)>;
 		compatible = "zephyr,memory-region", "mmio-sram";
 		zephyr,memory-region = "SRAM0";
+		#memory-region-cells = <0>;
 	};
 
 	/* System data RAM accessible over AHB bus: SRAM1 in D2 domain */
 	sram1: memory@30000000 {
 		reg = <0x30000000 DT_SIZE_K(16)>;
 		compatible = "zephyr,memory-region", "mmio-sram";
 		zephyr,memory-region = "SRAM1";
+		#memory-region-cells = <0>;
 		zephyr,memory-attr = <DT_MEM_ARM(ATTR_MPU_RAM)>;
 	};
 
@@ -69,6 +71,7 @@
 		compatible = "zephyr,memory-region", "mmio-sram";
 		reg = <0x30004000 DT_SIZE_K(16)>;
 		zephyr,memory-region = "SRAM2";
+		#memory-region-cells = <0>;
 		/* Disable SRAM2 by default to avoid unintended access.
 		 * To enable it, explicitly define zephyr,memory-attr
 		 * to configure MPU attributes.

dts/bindings/ethernet/st,stm32h7-ethernet.yaml

@@ -11,4 +11,11 @@ description: |
 
 compatible: "st,stm32h7-ethernet"
 
-include: st,stm32-ethernet-common.yaml
+include:
+  - "st,stm32-ethernet-common.yaml"
+  - "memory-region.yaml"
+
+properties:
+  memory-regions:
+    description: |
+      Reference to SRAM node used for Ethernet DMA buffer and descriptor.

soc/st/stm32/stm32h7rsx/mpu_regions.c

@@ -30,8 +30,10 @@ static const struct arm_mpu_region mpu_regions[] = {
 	/* Region 4 - Ready only flash with unique device id */
 	MPU_REGION_ENTRY("ID", 0x08FFF800, REGION_FLASH_ATTR(REGION_2K)),
 
-#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(mac))
-#define sram_eth_node DT_NODELABEL(sram2)
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(mac)) && \
+	DT_NODE_HAS_PROP(DT_NODELABEL(mac), memory_regions)
+#define sram_eth_node DT_PHANDLE(DT_NODELABEL(mac), memory_regions)
+
 #if DT_NODE_HAS_STATUS_OKAY(sram_eth_node)
 	/* Region 5 - Ethernet DMA buffer RAM */
 	MPU_REGION_ENTRY("SRAM_ETH_BUF", DT_REG_ADDR(sram_eth_node),
@@ -42,6 +44,12 @@ static const struct arm_mpu_region mpu_regions[] = {
 #endif
 };
 
+#ifdef sram_eth_node
+	BUILD_ASSERT(!DT_SAME_NODE(sram_eth_node, DT_CHOSEN(zephyr_sram)),
+	     "Remove property memory-regions from 'mac' node "
+	     "to locate ethernet buffers in system RAM.");
+#endif
+
 const struct arm_mpu_config mpu_config = {
 	.num_regions = ARRAY_SIZE(mpu_regions),
 	.mpu_regions = mpu_regions,

soc/st/stm32/stm32h7rsx/sections.ld

@@ -4,8 +4,10 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(mac))
-#define sram_eth_node	DT_NODELABEL(sram2)
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(mac)) && \
+    DT_NODE_HAS_PROP(DT_NODELABEL(mac), memory_regions)
+#define sram_eth_node DT_PHANDLE(DT_NODELABEL(mac), memory_regions)
+
 #if DT_NODE_HAS_STATUS_OKAY(sram_eth_node)
 SECTION_DATA_PROLOGUE(eth_stm32,(NOLOAD),)
 {

tests/drivers/memc/ram/boards/stm32h7s78_dk.overlay

@@ -8,3 +8,11 @@
 	zephyr,memory-attr = <DT_MEM_ARM(ATTR_MPU_RAM)>;
 	status = "okay";
 };
+
+&mac {
+	/*
+	 * mac is disabled for this test since the ethernet driver that gets
+	 * enabled by this node consumes the sram1 node thus failing this test
+	 */
+	status = "disabled";
+};