[RFC] riscv: visionfive2: use OF_BOARD_SETUP

[Torsten Duwe]

U-Boot already has a mechanism to fix up the DT before OS boot.
This avoids the excessive duplication of data and work proposed
by the explicit separation of 1.2a and 1.3b board revisions. It
will also, to a good degree, improve the user experience, as
pointed out by Matthias.

The defconfig changes required (in diffconfig format) are

-I2C n
-NET_RANDOM_ETHADDR y
+CMD_I2C y
+CMD_MISC y
+DM_I2C y
+I2C_EEPROM y
+MISC y
+MISC_INIT_R y
+OF_BOARD_SETUP y
+SPL_DM_I2C n
+SPL_MISC n
+SYS_I2C_DW y
+SYS_I2C_EEPROM_ADDR 0x0

along with the patch below. It has the neat side effect of providing
the network with the proper MAC addresses ;)

I take advantage of the fact that I²C-5 is also required to talk to the
PMIC, so it must already be initialised by OpenSBI. All that's required
is to declare the EEPROM and to pull in the drivers.

This is only a proof of concept; let me know if you like it and I can
add the other 12 DT patches to adjust_for_rev13b(), or maybe start with
1.3b as the default and go the other way, or something in between.

The last hunk, to the i2c Makefile, is IMHO an independent fix, because
the implication PCI => ACPI in designware_i2c_pci is invalid, and the
VisionFive2 config proves it. Use this quick hack for now.

Signed-off-by: Torsten Duwe <duwe at suse.de>

---
diff --git a/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi b/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
index ff9df56ec2..fd3a1d057a 100644
--- a/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
+++ b/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
@@ -119,6 +119,12 @@
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c5_pins>;
 	status = "okay";
+
+	eeprom at 50 {
+		compatible = "atmel,24c04";
+		reg = <0x50>;
+		pagesize = <0x10>;
+	};
 };
 
 &i2c6 {
diff --git a/board/starfive/visionfive2/starfive_visionfive2.c b/board/starfive/visionfive2/starfive_visionfive2.c
index 613fe793c4..d7f846a357 100644
--- a/board/starfive/visionfive2/starfive_visionfive2.c
+++ b/board/starfive/visionfive2/starfive_visionfive2.c
@@ -7,6 +7,10 @@
 #include <common.h>
 #include <asm/io.h>
 #include <cpu_func.h>
+#include <dm/uclass.h>
+#include <fdt_support.h>
+#include <i2c_eeprom.h>
+#include <net.h>
 #include <linux/bitops.h>
 
 #define JH7110_L2_PREFETCHER_BASE_ADDR		0x2030000
@@ -38,3 +42,62 @@ int board_init(void)
 
 	return 0;
 }
+
+#ifdef CONFIG_MISC_INIT_R
+int misc_init_r(void)
+{
+	int ret = 0;
+
+#ifdef CONFIG_I2C_EEPROM
+       struct udevice *dev;
+	char mac_addr[6];
+	unsigned char pcb_rev, BOM;
+
+	ret = uclass_first_device_err(UCLASS_I2C_EEPROM, &dev);
+	if (ret)
+		goto out;
+
+	if (eth_env_get_enetaddr("ethaddr", mac_addr) == 0) {
+		int i;
+		for (i=0; i<2; i++) {
+			ret = i2c_eeprom_read(dev, 0x78+6*i, mac_addr, 6);
+			if (!ret && is_valid_ethaddr(mac_addr))
+				eth_env_set_enetaddr_by_index("eth", i, mac_addr);
+		}
+	}
+
+	ret = i2c_eeprom_read(dev, 0x76, &pcb_rev, 1);
+	if (!ret)
+		env_set_hex("board_revision", pcb_rev);
+
+	ret = i2c_eeprom_read(dev, 0x77, &BOM, 1);
+
+	out:
+#endif
+        return ret;
+}
+#endif
+
+#ifdef CONFIG_OF_BOARD_SETUP
+static void adjust_for_rev13b(void * fdt)
+{
+	do_fixup_by_path(fdt, "/soc/ethernet at 16040000",
+			 "phy-mode", "rgmii-id", 9, 0);
+	/*
+	   ... other fixups ...
+
+	 */
+}
+
+int ft_board_setup(void *fdt, struct bd_info *bdip)
+{
+	unsigned char pcb_rev = 0;
+
+	pcb_rev = env_get_hex("board_revision", pcb_rev);
+	if (pcb_rev >= 0xB2) {
+		printf("Adjusting FDT for v1.3B board rev\n");
+		adjust_for_rev13b(fdt);
+	}
+	return 0;
+}
+#endif
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 99545df2e5..828856e40d 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -19,8 +19,10 @@ obj-$(CONFIG_SYS_I2C_CA) += i2c-cortina.o
 obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
 obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
 ifdef CONFIG_PCI
+ifdef CONFIG_ACPIGEN
 obj-$(CONFIG_SYS_I2C_DW) += designware_i2c_pci.o
 endif
+endif
 obj-$(CONFIG_SYS_I2C_FSL) += fsl_i2c.o
 obj-$(CONFIG_SYS_I2C_IHS) += ihs_i2c.o
 obj-$(CONFIG_SYS_I2C_INTEL) += intel_i2c.o