ARM: dts: stm32: Add KS8851-16MLL ethernet on FMC2

Add DT entries, Kconfig entries and board-specific entries to configure
FMC2 bus and make KS8851-16MLL on that bus accessible to U-Boot.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>

3 files changed, 121 insertions, 0 deletions

diff --git a/arch/arm/dts/stm32mp15xx-dhcom-u-boot.dtsi b/arch/arm/dts/stm32mp15xx-dhcom-u-boot.dtsi
index 62c45def43..b57f3d520c 100644
--- a/arch/arm/dts/stm32mp15xx-dhcom-u-boot.dtsi
+++ b/arch/arm/dts/stm32mp15xx-dhcom-u-boot.dtsi
@@ -37,6 +37,12 @@
 			default-state = "on";
 		};
 	};
+
+	/* This is actually on FMC2, but we do not have bus driver for that */
+	ksz8851: ks8851mll@64000000 {
+		compatible = "micrel,ks8851-mll";
+		reg = <0x64000000 0x20000>;
+	};
 };
 
 &i2c4 {
@@ -50,6 +56,68 @@
 	};
 };
 
+&pinctrl {
+	/* These should bound to FMC2 bus driver, but we do not have one */
+	pinctrl-0 = <&fmc_pins_b>;
+	pinctrl-1 = <&fmc_sleep_pins_b>;
+	pinctrl-names = "default", "sleep";
+
+	fmc_pins_b: fmc-0 {
+		pins1 {
+			pinmux = <STM32_PINMUX('D', 4, AF12)>, /* FMC_NOE */
+				 <STM32_PINMUX('D', 5, AF12)>, /* FMC_NWE */
+				 <STM32_PINMUX('B', 7, AF12)>, /* FMC_NL */
+				 <STM32_PINMUX('D', 14, AF12)>, /* FMC_D0 */
+				 <STM32_PINMUX('D', 15, AF12)>, /* FMC_D1 */
+				 <STM32_PINMUX('D', 0, AF12)>, /* FMC_D2 */
+				 <STM32_PINMUX('D', 1, AF12)>, /* FMC_D3 */
+				 <STM32_PINMUX('E', 7, AF12)>, /* FMC_D4 */
+				 <STM32_PINMUX('E', 8, AF12)>, /* FMC_D5 */
+				 <STM32_PINMUX('E', 9, AF12)>, /* FMC_D6 */
+				 <STM32_PINMUX('E', 10, AF12)>, /* FMC_D7 */
+				 <STM32_PINMUX('E', 11, AF12)>, /* FMC_D8 */
+				 <STM32_PINMUX('E', 12, AF12)>, /* FMC_D9 */
+				 <STM32_PINMUX('E', 13, AF12)>, /* FMC_D10 */
+				 <STM32_PINMUX('E', 14, AF12)>, /* FMC_D11 */
+				 <STM32_PINMUX('E', 15, AF12)>, /* FMC_D12 */
+				 <STM32_PINMUX('D', 8, AF12)>, /* FMC_D13 */
+				 <STM32_PINMUX('D', 9, AF12)>, /* FMC_D14 */
+				 <STM32_PINMUX('D', 10, AF12)>, /* FMC_D15 */
+				 <STM32_PINMUX('G', 9, AF12)>, /* FMC_NE2_FMC_NCE */
+				 <STM32_PINMUX('G', 12, AF12)>; /* FMC_NE4 */
+			bias-disable;
+			drive-push-pull;
+			slew-rate = <3>;
+		};
+	};
+
+	fmc_sleep_pins_b: fmc-sleep-0 {
+		pins {
+			pinmux = <STM32_PINMUX('D', 4, ANALOG)>, /* FMC_NOE */
+				 <STM32_PINMUX('D', 5, ANALOG)>, /* FMC_NWE */
+				 <STM32_PINMUX('B', 7, ANALOG)>, /* FMC_NL */
+				 <STM32_PINMUX('D', 14, ANALOG)>, /* FMC_D0 */
+				 <STM32_PINMUX('D', 15, ANALOG)>, /* FMC_D1 */
+				 <STM32_PINMUX('D', 0, ANALOG)>, /* FMC_D2 */
+				 <STM32_PINMUX('D', 1, ANALOG)>, /* FMC_D3 */
+				 <STM32_PINMUX('E', 7, ANALOG)>, /* FMC_D4 */
+				 <STM32_PINMUX('E', 8, ANALOG)>, /* FMC_D5 */
+				 <STM32_PINMUX('E', 9, ANALOG)>, /* FMC_D6 */
+				 <STM32_PINMUX('E', 10, ANALOG)>, /* FMC_D7 */
+				 <STM32_PINMUX('E', 11, ANALOG)>, /* FMC_D8 */
+				 <STM32_PINMUX('E', 12, ANALOG)>, /* FMC_D9 */
+				 <STM32_PINMUX('E', 13, ANALOG)>, /* FMC_D10 */
+				 <STM32_PINMUX('E', 14, ANALOG)>, /* FMC_D11 */
+				 <STM32_PINMUX('E', 15, ANALOG)>, /* FMC_D12 */
+				 <STM32_PINMUX('D', 8, ANALOG)>, /* FMC_D13 */
+				 <STM32_PINMUX('D', 9, ANALOG)>, /* FMC_D14 */
+				 <STM32_PINMUX('D', 10, ANALOG)>, /* FMC_D15 */
+				 <STM32_PINMUX('G', 9, ANALOG)>, /* FMC_NE2_FMC_NCE */
+				 <STM32_PINMUX('G', 12, ANALOG)>; /* FMC_NE4 */
+		};
+	};
+};
+
 &pmic {
 	u-boot,dm-pre-reloc;
 };
diff --git a/board/dhelectronics/dh_stm32mp1/board.c b/board/dhelectronics/dh_stm32mp1/board.c
index 7bcd713a86..a3458a2623 100644
--- a/board/dhelectronics/dh_stm32mp1/board.c
+++ b/board/dhelectronics/dh_stm32mp1/board.c
@@ -375,6 +375,56 @@ static void sysconf_init(void)
 #endif
 }
 
+static void board_init_fmc2(void)
+{
+#define STM32_FMC2_BCR1			0x0
+#define STM32_FMC2_BTR1			0x4
+#define STM32_FMC2_BWTR1		0x104
+#define STM32_FMC2_BCR(x)		((x) * 0x8 + STM32_FMC2_BCR1)
+#define STM32_FMC2_BCRx_FMCEN		BIT(31)
+#define STM32_FMC2_BCRx_WREN		BIT(12)
+#define STM32_FMC2_BCRx_RSVD		BIT(7)
+#define STM32_FMC2_BCRx_FACCEN		BIT(6)
+#define STM32_FMC2_BCRx_MWID(n)		((n) << 4)
+#define STM32_FMC2_BCRx_MTYP(n)		((n) << 2)
+#define STM32_FMC2_BCRx_MUXEN		BIT(1)
+#define STM32_FMC2_BCRx_MBKEN		BIT(0)
+#define STM32_FMC2_BTR(x)		((x) * 0x8 + STM32_FMC2_BTR1)
+#define STM32_FMC2_BTRx_DATAHLD(n)	((n) << 30)
+#define STM32_FMC2_BTRx_BUSTURN(n)	((n) << 16)
+#define STM32_FMC2_BTRx_DATAST(n)	((n) << 8)
+#define STM32_FMC2_BTRx_ADDHLD(n)	((n) << 4)
+#define STM32_FMC2_BTRx_ADDSET(n)	((n) << 0)
+
+#define RCC_MP_AHB6RSTCLRR		0x218
+#define RCC_MP_AHB6RSTCLRR_FMCRST	BIT(12)
+#define RCC_MP_AHB6ENSETR		0x19c
+#define RCC_MP_AHB6ENSETR_FMCEN		BIT(12)
+
+	const u32 bcr = STM32_FMC2_BCRx_WREN |STM32_FMC2_BCRx_RSVD |
+			STM32_FMC2_BCRx_FACCEN | STM32_FMC2_BCRx_MWID(1) |
+			STM32_FMC2_BCRx_MTYP(2) | STM32_FMC2_BCRx_MUXEN |
+			STM32_FMC2_BCRx_MBKEN;
+	const u32 btr = STM32_FMC2_BTRx_DATAHLD(3) |
+			STM32_FMC2_BTRx_BUSTURN(2) |
+			STM32_FMC2_BTRx_DATAST(0x22) |
+			STM32_FMC2_BTRx_ADDHLD(2) |
+			STM32_FMC2_BTRx_ADDSET(2);
+
+	/* Set up FMC2 bus for KS8851-16MLL and X11 SRAM */
+	writel(RCC_MP_AHB6RSTCLRR_FMCRST, STM32_RCC_BASE + RCC_MP_AHB6RSTCLRR);
+	writel(RCC_MP_AHB6ENSETR_FMCEN, STM32_RCC_BASE + RCC_MP_AHB6ENSETR);
+
+	/* KS8851-16MLL -- Muxed mode */
+	writel(bcr, STM32_FMC2_BASE + STM32_FMC2_BCR(1));
+	writel(btr, STM32_FMC2_BASE + STM32_FMC2_BTR(1));
+	/* AS7C34098 SRAM on X11 -- Muxed mode */
+	writel(bcr, STM32_FMC2_BASE + STM32_FMC2_BCR(3));
+	writel(btr, STM32_FMC2_BASE + STM32_FMC2_BTR(3));
+
+	setbits_le32(STM32_FMC2_BASE + STM32_FMC2_BCR1, STM32_FMC2_BCRx_FMCEN);
+}
+
 /* board dependent setup after realloc */
 int board_init(void)
 {
@@ -398,6 +448,8 @@ int board_init(void)
 
 	sysconf_init();
 
+	board_init_fmc2();
+
 	if (CONFIG_IS_ENABLED(CONFIG_LED))
 		led_default_state();
 
diff --git a/configs/stm32mp15_dhcom_basic_defconfig b/configs/stm32mp15_dhcom_basic_defconfig
index 921dea242a..683f15e7d5 100644
--- a/configs/stm32mp15_dhcom_basic_defconfig
+++ b/configs/stm32mp15_dhcom_basic_defconfig
@@ -93,6 +93,7 @@ CONFIG_SPI_FLASH_MTD=y
 CONFIG_SPL_SPI_FLASH_MTD=y
 CONFIG_DM_ETH=y
 CONFIG_DWC_ETH_QOS=y
+CONFIG_KS8851_MLL=y
 CONFIG_PHY=y
 CONFIG_PHY_STM32_USBPHYC=y
 CONFIG_PINCONF=y