This is an old revision of the document!
Edge2 have advanced and flexible boot flow … see also Edge2 boot sequence
MCU ⇒ BROM ⇒ SPL ⇒ U-Boot ⇒ OS target
Next information actual for MCU ver: 0x0002
POWER
+ RESET
- force boot from SD/eMMC.FUNCTION
x3 times - flash mode More detail: hardware-buttons
See too: mcu-registers-annotation
Common boot mode configuration 0x20
boot mode | value |
---|---|
spi | 0 |
mmc | 1 |
i2cget -f -y 2 0x18 0x20
This flag 0x92
will be used one time on next reboot! and not change common boot-mode
boot flag | value |
---|---|
disabled | 0 |
OOWOW request | 1 |
boot from SPI | 2 |
boot from eMMC | 3 |
i2cget -f -y 2 0x18 0x92
boot-flag will be used only one time and after reboot will be masked by ^ 0x50
on SPL stage
boot flag note | mask |
---|---|
spl mask | 0x50 |
oowow mask | 0xA0 |
boot-flag value > 10
will be reset to 0
on reboot SPL stage
We can reboot device by non standard way via MCU 0x91
register with special options.
reboot mode | value |
---|---|
SPI | 0 |
normal reboot | 1 |
eMMC | 2 |
i2cset -f -y 2 0x18 0x91 value
Device will be rebooted immediately after successful writing to 0x91
MCU register
Only normal reboot == 1
dos not change boot-flag on next reboot!
SPI == 0
will change boot-flag to 2
on next reboot
eMMC == 2
will change boot-flag to 3
on next reboot
See too: mcu-registers-annotation
## read current boot-mode ~# bootmode spi ## setup to MMC ~# bootmode mmc [i] /opt/bootmode spi -> mmc(sd) ~# bootmode mmc ## setup to SPI ~# bootmode spi [i] /opt/bootmode mmc -> spi
~# mcu_oowow_mode set 1 [i] set with 1 ~# mcu_oowow_mode clean [i] set with 0 ~# mcu_oowow_mode && echo activated 0x01 activated ~# mcu_oowow_mode clean [i] set with 0 ~# mcu_oowow_mode || echo disabled disabled ~# i2cset -f -y 2 0x18 0x92 1 ~# i2cget -f -y 2 0x18 0x92 0x01
Forced hardware reboot
## oowow shell ~# mcu_reboot ## common system ~# i2cset -f -y 2 0x18 0x91 1
i2cset -f -y 2 0x18 0x92 1 i2cset -f -y 2 0x18 0x91 1
i2cset -f -y 2 0x18 0x91 0
SPL boot loader priority: spi
⇒ emmc
⇒ sd
- hard-coded by MCU and BROM
SPL boot loader priority not same as mcu bootmode. MCU boot mode works only after SPL boot stage passed.
Boot mode mmc
logs:
Current u-boot can start OS from USB
⇒ SD
⇒ eMMC
⇒ …
kedge2# printenv boot_targets
boot_targets=usb0 mmc1 mmc0 pxe dhcp fail
default eMMC u-boot log for Ubuntu images
kedge2# printenv boot_targets
boot_targets=usb0 mmc1 mmc0 pxe dhcp
MCU version: 02 & 03 0x91 REBOOT_MODE 0 - reset and boot from SPI 1 - reset normal 2 - reset and boot from eMMC 0x92 BOOT_FLAG 0 - normal 1 - press FUNC boot-up 2 - reset from SPI boot-up 3 - reset from eMMC boot-up
See too: mcu-features
// ...... /* khadas mcu part begin */ #define MCU_I2C_BUS_NUM 2 #define MCU_I2C_CHIP_ADDR 0x18 #define MCU_I2C_REG_BOOT_MODE 0x20 #define MCU_I2C_REG_BOOT_MODE_SPI 0x00 #define MCU_I2C_REG_BOOT_MODE_MMC 0x01 #define MCU_I2C_REG_BOOT_FLAG 0x92 #define MCU_I2C_REG_RESET_MODE 0x91 #define MCU_I2C_REG_BOOT_FLAG_NORMAL 0x00 #define MCU_I2C_REG_BOOT_FLAG_FUNC 0x01 #define MCU_I2C_REG_BOOT_FLAG_OOWOW 0x01 #define MCU_I2C_REG_BOOT_FLAG_SPI 0x02 #define MCU_I2C_REG_BOOT_FLAG_EMMC 0x03 #define MCU_I2C_REG_BOOT_FLAG_RESCUE 0x05 #define MCU_I2C_REG_BOOT_FLAG_PASS 0x50 #define MCU_I2C_REG_LED 0x89 /* khadas mcu part end */ void board_boot_order(u32 *spl_boot_list) { const void *blob = gd->fdt_blob; int chosen_node = fdt_path_offset(blob, "/chosen"); int idx = 0; int elem; int boot_device; int node; const char *conf; /* khadas mcu part begin */ uchar mcu_boot_mode; uchar mcu_boot_flag; uchar mcu_led_normal = 8; /* white breath */ uchar mcu_led_reset = 1; /* white solid */ int ret; struct udevice *bus; struct udevice *dev; ret = uclass_first_device(UCLASS_I2C, &bus); if (ret) goto mcu_skip; ret = i2c_get_chip(bus, MCU_I2C_CHIP_ADDR, 1, &dev); if (ret) goto mcu_skip; ret = dm_i2c_read(dev, MCU_I2C_REG_BOOT_MODE, &mcu_boot_mode, 1); ret = dm_i2c_read(dev, MCU_I2C_REG_BOOT_FLAG, &mcu_boot_flag, 1); printf("MCU: boot mode 0x20: %d, flag 0x92: %d\n", mcu_boot_mode, mcu_boot_flag); // reset boot flag if ( mcu_boot_flag != 0 ) { mcu_boot_flag = mcu_boot_flag > 10 ? 0 : mcu_boot_flag ^ MCU_I2C_REG_BOOT_FLAG_PASS; dm_i2c_write(dev, MCU_I2C_REG_BOOT_FLAG, &mcu_boot_flag, 1); printf("MCU: boot flag < %d\n", mcu_boot_flag); if ( mcu_boot_flag != 0 ) dm_i2c_write(dev, MCU_I2C_REG_LED, &mcu_led_reset, 1); } else { dm_i2c_write(dev, MCU_I2C_REG_LED, &mcu_led_normal, 1); } mcu_skip: /* khadas mcu part end */ if (chosen_node < 0) { debug("%s: /chosen not found, using spl_boot_device()\n", __func__); spl_boot_list[0] = spl_boot_device(); return; } printf("%s: /chosen found, using spl_boot_device()\n", __func__); for (elem = 0; (conf = fdt_stringlist_get(blob, chosen_node, "u-boot,spl-boot-order", elem, NULL)); elem++) { const char *alias; printf("!!! %s: \n", conf); /* Handle the case of 'same device the SPL was loaded from' */ if (strncmp(conf, "same-as-spl", 11) == 0) { // /mmc@fe2c0000 - SD // /mmc@fe2e0000 - EMMC mcu_boot_flag &= 0x0F; // restore original flag if (mcu_boot_flag == 1 || mcu_boot_flag == 2 || mcu_boot_flag == 5) conf = "/spi@fe2b0000/flash@1"; else if (mcu_boot_flag == 3) conf = "/mmc@fe2e0000"; else if (mcu_boot_mode == MCU_I2C_REG_BOOT_MODE_MMC) continue; else conf = board_spl_was_booted_from(); printf("+++ %s: \n", conf); if (!conf) continue; } /* First check if the list element is an alias */ alias = fdt_get_alias(blob, conf); if (alias) conf = alias; /* Try to resolve the config item (or alias) as a path */ node = fdt_path_offset(blob, conf); if (node < 0) { debug("%s: could not find %s in FDT", __func__, conf); continue; } /* Try to map this back onto SPL boot devices */ boot_device = spl_node_to_boot_device(node); if (boot_device < 0) { debug("%s: could not map node @%x to a boot-device\n", __func__, node); continue; } spl_boot_list[idx++] = boot_device; } /* If we had no matches, fall back to spl_boot_device */ if (idx == 0) spl_boot_list[0] = spl_boot_device(); } #endif
0x000000000000-0x000000080000 : "bootloader" # 0x03f800 bytes x 2 > 0x000000 0x040000 < 0 0x000000080000-0x0000000a6000 : "bl2e" # 0x013000 bytes x 2 > 0x080000 0x093000 < 0x00040000 0x0000000a6000-0x0000000c8000 : "bl2x" # 0x011000 bytes x 2 > 0x0a6000 0x0b7000 < 0x00053000 0x0000000c8000-0x000000148000 : "ddrfip" # 0x040000 bytes x 2 > 0x0c8000 0x108000 < 0x00064000 0x000000148000-0x000000448000 : "devfip" # 0x275000 bytes > 0x148000 < 0x000a4000 0x000000448000-0x000000488000 : "env" # zero 0x000000488000-0x0000004c8000 : "dtb" # zero 0x0000004c8000-0x0000006c8000 : "boot" # zero 0x0000006c8000-0x000002000000 : "user" # zero