On 9/11/21 1:31 PM, Sean Anderson wrote: > +CC Heinrich > > Did you ever try booting with WDT on k210? > > On 9/11/21 12:43 PM, Samuel Holland wrote: >> Hello, >> >> I am porting U-Boot to the Allwinner D1 SoC, and I ran into an issue >> where the board fails to boot if I enable watchdog auto-start. >> >> The call to get_timer() -> get_ticks() panics because no timer is >> available. And since panic_finish() calls udelay(), this causes infinite >> recursion of trying and failing to get the timer. >> >> The issue is that the RISC-V architectural timer driver is bound in >> arch_early_init_r, which is only called _after_ the first instance of >> INIT_FUNC_WATCHDOG_RESET in the initcall list. >> >> Below is a boot log where I commented out the calls to get_timer() and >> time_after_eq() in watchdog_reset() in order to illustrate the problem. >> >> I modified the log to add the initcall symbol names for clarity. >> >>> U-Boot 2021.10-rc2-00278-ge2be1a426d6-dirty (Jan 01 1970 - 00:00:00 >>> +0000) >>> >>> DRAM: 512 MiB >>> initcall: 000000005ff63916 >>> initcall: 000000005ff6391a >>> initcall: 000000004a012a4e (initr_reloc_global_data) >>> initcall: 000000004a012a88 (initr_barrier) >>> initcall: 000000004a012a1c (initr_malloc) >>> Pre-reloc malloc() used 0x720 bytes (1 KB) >>> initcall: 000000004a01290e (log_init) >>> initcall: 000000004a012a94 (initr_bootstage) >>> initcall: 000000004a012a8c (initr_of_live) >>> initcall: 000000004a012a06 (initr_dm) >>> Binding device root_driver to driver root_driver >>> Probing device root_driver with driver root_driver >>> Binding device osc24M_clk to driver fixed_clock >>> Binding device soc to driver simple_bus >>> Binding device pinctrl@2000000 to driver sunxi-pinctrl >>> Binding device pinctrl@2000000 to driver gpio_sunxi >>> Binding device PA to driver gpio_sunxi >>> Binding device PB to driver gpio_sunxi >>> Binding device PC to driver gpio_sunxi >>> Binding device PD to driver gpio_sunxi >>> Binding device PE to driver gpio_sunxi >>> Binding device PF to driver gpio_sunxi >>> Binding device PG to driver gpio_sunxi >>> Binding device i2c0-pb10-pins to driver pinconfig >>> Binding device i2c2-pb0-pins to driver pinconfig >>> Binding device mmc0-pins to driver pinconfig >>> Binding device mmc1-pins to driver pinconfig >>> Binding device rgmii-pe-pins to driver pinconfig >>> Binding device spi0-pins to driver pinconfig >>> Binding device spi1-pd-pins to driver pinconfig >>> Binding device uart0-pb8-pins to driver pinconfig >>> Binding device uart1-pg6-pins to driver pinconfig >>> Binding device uart1-pg8-rts-cts-pins to driver pinconfig >>> Binding device i2s2-pb-pins to driver pinconfig >>> Binding device i2s2-pb3-din-pin to driver pinconfig >>> Binding device i2s2-pb4-dout-pin to driver pinconfig >>> Binding device ledc-pc0-pin to driver pinconfig >>> Binding device pwm0-pd16-pin to driver pinconfig >>> Binding device pwm2-pd18-pin to driver pinconfig >>> Binding device pwm7-pd22-pin to driver pinconfig >>> Binding device spdif-pd22-pin to driver pinconfig >>> Binding device clock-controller@2001000 to driver sun50i_d1_ccu >>> Binding device reset to driver sunxi_reset >>> Binding device serial@2500000 to driver ns16550_serial >>> Binding device serial@2500400 to driver ns16550_serial >>> Binding device i2c@2502000 to driver i2c_mvtwsi >>> Binding device i2c@2502800 to driver i2c_mvtwsi >>> Binding device mmc@4020000 to driver sunxi_mmc >>> Binding device m...@4020000.blk to driver mmc_blk >>> Binding device mmc@4021000 to driver sunxi_mmc >>> Binding device m...@4021000.blk to driver mmc_blk >>> Binding device usb@4100000 to driver sunxi-musb >>> Binding device phy@4100400 to driver sun4i_usb_phy >>> Binding device usb@4101000 to driver ehci_generic >>> Binding device usb@4101400 to driver ohci_generic >>> Binding device usb@4200000 to driver ehci_generic >>> Binding device usb@4200400 to driver ohci_generic >>> Binding device ethernet@4500000 to driver eth_sun8i_emac >>> Binding device watchdog@6011000 to driver sunxi_wdt >>> initcall: 000000004a001914 (board_init) >>> initcall: 000000004a04d814 (efi_memory_init) >>> initcall: 000000004a012a9c (initr_binman) >>> initcall: 000000004a012a90 (initr_dm_devices) >> >> Here's where dm_timer_init() would be called if CONFIG_TIMER_EARLY was >> enabled, but that still doesn't help because the timer is not bound yet. >> In fact, CONFIG_TIMER_EARLY actually makes the situation worse, because >> the board hangs if dm_timer_init() fails: >> >> initcall sequence 000000005ffdac78 failed at call 000000004a012a06 >> (err=-19) >> ### ERROR ### Please RESET the board ### > > I'm not sure what's going on here. Why does dm_timer_init get called > from initr_dm?
dm_timer_init gets called from initr_dm_devices (not initr_dm) if CONFIG_TIMER_EARLY is enabled. > Why does it fail? It fails because at this point there are no devices bound for the timer uclass, so uclass_first_device_err returns -ENODEV. Regards, Samuel > --Sean > >>> initcall: 000000004a01c4f4 (stdio_init_tables) >>> initcall: 000000004a039ff8 (serial_initialize) >>> Probing device pinctrl@2000000 with driver sunxi-pinctrl >>> Probing device soc with driver simple_bus >>> Probing device clock-controller@2001000 with driver sun50i_d1_ccu >>> Probing device osc24M_clk with driver fixed_clock >>> Probing device uart0-pb8-pins with driver pinconfig >>> Probing device serial@2500000 with driver ns16550_serial >>> Probing device reset with driver sunxi_reset >>> initcall: 000000004a0129ea (initr_announce) >>> Now running in RAM - U-Boot at: 5ff51000 >>> initcall: 000000004a0367ce (initr_watchdog) >>> Probing device watchdog@6011000 with driver sunxi_wdt >>> WDT: Started with servicing (16s timeout) >>> initcall: 000000004a012610 (init_func_watchdog_reset) >> >> Here's where the timer needs to be available for watchdog auto-start to >> work. An unpatched U-Boot would panic here. >> >>> initcall: 000000004a012a84 (arch_initr_trap) >>> initcall: 000000004a012610 (init_func_watchdog_reset) >>> initcall: 000000004a012610 (init_func_watchdog_reset) >>> initcall: 000000004a000ed4 (arch_early_init_r) >>> Binding device cpus to driver cpu_bus >>> Binding device cpu@0 to driver riscv_cpu >>> Binding device riscv_timer to driver riscv_timer >> >> But here is where the timer device is actually bound. >> >> Do you have any suggestions for how best to fix this? >> >> Some things I can think of: >> - Add an option to probe the CPU device early in initr_dm_devices() >> - Require the board to probe the CPU device from board_init() >> - Move arch_early_init_r() earlier in the initcall list >> - Skip restarting the watchdog until a timer is available (but this >> would not fix CONFIG_TIMER_EARLY) >> >> Thanks, >> Samuel >> >>> Probing device cpus with driver cpu_bus >>> Probing device cpu@0 with driver riscv_cpu >>> Binding device sbi-sysreset to driver sbi-sysreset >>> initcall: 000000004a012a98 (power_init_board) >>> initcall: 000000004a012610 (init_func_watchdog_reset) >>> initcall: 000000004a0129ca (initr_mmc) >>> MMC: Probing device mmc0-pins with driver pinconfig >>> Probing device mmc@4020000 with driver sunxi_mmc >>> Probing device pinctrl@2000000 with driver gpio_sunxi >>> Probing device PF with driver gpio_sunxi >>> Need to init timer! >>> Probing device riscv_timer with driver riscv_timer >>> Timer is 000000005df34f80 >>> Read timer, got 0x17dacfb >>> Timer is 000000005df34f80 >>> Read timer, got 0x17f63b8 >>> Probing device mmc1-pins with driver pinconfig >>> Probing device mmc@4021000 with driver sunxi_mmc >>> Timer is 000000005df34f80 >>> Read timer, got 0x186be7e >>> Timer is 000000005df34f80 >>> Read timer, got 0x188752e >>> mmc@4020000: 0, mmc@4021000: 1 >>> initcall: 000000004a012970 (relocated to 000000005ff63970) >>> Loading Environment from nowhere... OK >>> initcall: 000000004a012610 (relocated to 000000005ff63610) >>> initcall: 000000004a012912 (relocated to 000000005ff63912) >>> initcall: 000000004a012610 (relocated to 000000005ff63610) >>> initcall: 000000004a01c50c (relocated to 000000005ff6d50c) >>> initcall: 000000004a010938 (relocated to 000000005ff61938) >>> initcall: 000000004a0188bc (relocated to 000000005ff698bc) >>> In: serial@2500000 >>> Out: serial@2500000 >>> Err: serial@2500000 >>> initcall: 000000004a012610 (relocated to 000000005ff63610) >>> initcall: 000000004a0012dc (relocated to 000000005ff522dc) >>> initcall: 000000004a012950 (relocated to 000000005ff63950) >>> initcall: 000000004a012610 (relocated to 000000005ff63610) >>> initcall: 000000004a012934 (relocated to 000000005ff63934) >>> Net: phy interface8 >>> Probing device rgmii-pe-pins with driver pinconfig >>> Probing device ethernet@4500000 with driver eth_sun8i_emac >>> Timer is 000000005df34f80 >>> Read timer, got 0x1ae9538 >>> Timer is 000000005df34f80 >>> Read timer, got 0x1b04bed >>> Timer is 000000005df34f80 >>> Read timer, got 0x1b202af >>> Timer is 000000005df34f80 >>> Read timer, got 0x1b3b96e >>> Timer is 000000005df34f80 >>> Read timer, got 0x1b5702c >>> Timer is 000000005df34f80 >>> Read timer, got 0x1b726ec >>> >>> Warning: ethernet@4500000 (eth0) using random MAC address - >>> 62:69:97:68:19:04 >>> eth0: ethernet@4500000 >>> initcall: 000000004a01292a (relocated to 000000005ff6392a) >>> Hit any key to stop autoboot: 0 >> >> >
