[REGRESSION] Out of memory error: unable to boot on imx8mp/imx8mm

[Francesco Dolcini]

+Fabio, Marex, Peng, Frieder

On Tue, Dec 17, 2024 at 08:18:50AM -0300, João Paulo Gonçalves wrote:
> > 
> > Okay. Please try changing the value of ram_top to 0x1_0000_0000
> > instead of 0xFFFF_FFFF. That should work.
> >
> 
> Changing ram_top to 0x1_0000_0000 worked:
> 
> U-Boot SPL 2025.01-rc4-00025-g100a40dd79f8 (Dec 17 2024 - 08:05:06 -0300)
> DDR configured as dual rank
> WDT:   Started watchdog at 30280000 with servicing every 1000ms (60s timeout)
> SEC0:  RNG instantiated
> Normal Boot
> Trying to boot from BOOTROM
> Boot Stage: Primary boot
> Find img info 0x4802d400, size 1116
> Need continue download 1024
> NOTICE:  BL31: v2.6(release):lf_v2.6-g3c1583ba0a
> NOTICE:  BL31: Built : 11:00:38, Nov 21 2022
> 
> 
> U-Boot 2025.01-rc4-00025-g100a40dd79f8 (Dec 17 2024 - 08:05:06 -0300)
> 
> CPU:   Freescale i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
> CPU:   Industrial temperature grade (-40C to 105C) at 54C
> Reset cause: POR
> DRAM:  Ram top: 100000000
> 8 GiB
> Core:  183 devices, 31 uclasses, devicetree: separate
> WDT:   Started watchdog at 30280000 with servicing every 1000ms (60s timeout)
> MMC:   FSL_SDHC: 1, FSL_SDHC: 2
> Loading Environment from MMC... Reading from MMC(2)... OK
> In:    serial at 30880000
> Out:   serial at 30880000
> Err:   serial at 30880000
> Model: Toradex 0070 Verdin iMX8M Plus Quad 8GB WB IT V1.1A
> Serial#: 15207893
> Carrier: Toradex Dahlia V1.1C, Serial# 11060859
> SEC0:  RNG instantiated
> Setting variant to wifi
> Net:   eth1: ethernet at 30be0000, eth0: ethernet at 30bf0000 [PRIME]
> Hit any key to stop autoboot:  0 
> MMC: no card present
> switch to partitions #0, OK
> mmc2(part 0) is current device
> Scanning mmc 2:1...
> Found U-Boot script /boot.scr
> 5974 bytes read in 1 ms (5.7 MiB/s)
> ## Executing script at 50280000
> Loading DeviceTree: imx8mp-verdin-wifi-dev.dtb
> ...
> Starting kernel ...
> 
> The change is shown in the patch below, but I am unsure if this is the
> correct solution. Should ram_top be the last valid address or the upper
> bound?
> 
> diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c
> index 9588b8b28bf2..e01774ebc8a4 100644
> --- a/arch/arm/mach-imx/imx8m/soc.c
> +++ b/arch/arm/mach-imx/imx8m/soc.c
> @@ -362,7 +362,7 @@ phys_addr_t board_get_usable_ram_top(phys_size_t total_size)
>          * space below the 4G address boundary (which is 3GiB big),
>          * even when the effective available memory is bigger.
>          */
> -       top_addr = clamp_val((u64)PHYS_SDRAM + gd->ram_size, 0, 0xffffffff);
> +       top_addr = clamp_val((u64)PHYS_SDRAM + gd->ram_size, 0, 0x100000000);
>  
>         /*
>          * rom_pointer[0] stores the TEE memory start address.

see commit e27bddff4b97 ("imx8m: Restrict usable memory to space below 4G boundary").

I assume such a change might introduce regressions.

Francesco