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From: Joost van Zwieten <joost@diskos.nl>
To: Tom Rini <trini@konsulko.com>
Cc: Jaehoon Chung <jh80.chung@samsung.com>, u-boot@lists.denx.de
Subject: Re: kernel doesn't start on Odroid U2 unless setting initrd_high
Date: Wed, 11 Jan 2023 22:08:59 +0100	[thread overview]
Message-ID: <ZQACOR.7QWCDFUGRWRZ2@diskos.nl> (raw)
In-Reply-To: <20230111203844.GO3787616@bill-the-cat>



On Wed, Jan 11, 2023 at 15:38, Tom Rini <trini@konsulko.com> wrote:
> On Wed, Jan 11, 2023 at 09:28:42PM +0100, Joost van Zwieten wrote:
>> 
>> 
>>  On Tue, Jan 10, 2023 at 18:29, Tom Rini <trini@konsulko.com> wrote:
>>  > On Wed, Jan 11, 2023 at 12:10:42AM +0100, Joost van Zwieten wrote:
>>  > >
>>  > >
>>  > >  On Tue, Jan 10, 2023 at 18:08, Tom Rini <trini@konsulko.com> 
>> wrote:
>>  > >  > On Wed, Jan 11, 2023 at 12:01:46AM +0100, Joost van Zwieten 
>> wrote:
>>  > >  > >
>>  > >  > >
>>  > >  > >  On Tue, Jan 10, 2023 at 13:41, Tom Rini 
>> <trini@konsulko.com>
>>  > > wrote:
>>  > >  > >  > On Tue, Jan 10, 2023 at 09:13:32AM +0100, Joost van 
>> Zwieten
>>  > > wrote:
>>  > >  > >  >
>>  > >  > >  > >  Dear maintainers,
>>  > >  > >  > >
>>  > >  > >  > >  As of commit 4963f63fe61f15329d77472a762b1d8bf754d24b
>>  > > U-Boot
>>  > >  > > fails
>>  > >  > >  > > to start
>>  > >  > >  > >  a kernel (with `bootz`) on my Odroid U2 unless I 
>> force
>>  > >  > >  > > `initrd_high`, e.g.
>>  > >  > >  > >  to `0x50000000`. With commit 4963f63f and 
>> `initrd_high`
>>  > >  > > *unset* I
>>  > >  > >  > > get the
>>  > >  > >  > >  following output:
>>  > >  > >  > >
>>  > >  > >  > >     U-Boot 2020.10-rc2-00314-g4963f63fe6 (Jan 09 2023 
>> -
>>  > > 23:59:31
>>  > >  > >  > > +0100)
>>  > >  > >  > >
>>  > >  > >  > >     CPU: Exynos4412 @ 1 GHz
>>  > >  > >  > >     Model: Odroid based on Exynos4412
>>  > >  > >  > >     Type: u3
>>  > >  > >  > >     DRAM: 2 GiB
>>  > >  > >  > >     LDO20@VDDQ_EMMC_1.8V: set 1800000 uV; enabling
>>  > >  > >  > >     LDO22@VDDQ_EMMC_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     LDO21@TFLASH_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     MMC: SAMSUNG SDHCI: 2, EXYNOS DWMMC: 0
>>  > >  > >  > >     Loading Environment from MMC... *** Warning - bad 
>> CRC,
>>  > > using
>>  > >  > >  > > default
>>  > >  > >  > >  environment
>>  > >  > >  > >
>>  > >  > >  > >     In: serial
>>  > >  > >  > >     Out: serial
>>  > >  > >  > >     Err: serial
>>  > >  > >  > >     Boot device: MMC(2)
>>  > >  > >  > >     Net: No ethernet found.
>>  > >  > >  > >     Hit any key to stop autoboot: 0
>>  > >  > >  > >     Odroid # env set fk_kvers 5.10.0-20-armmp
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > > ${fdt_addr_r}
>>  > >  > >  > >  /boot/dtbs/${fk_kvers}/exynos4412-odroidu3.dtb
>>  > >  > >  > >     53440 bytes read in 50 ms (1 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${kernel_addr_r}
>>  > >  > >  > >  /boot/vmlinuz-${fk_kvers}
>>  > >  > >  > >     4973056 bytes read in 182 ms (26.1 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${ramdisk_addr_r}
>>  > >  > >  > >  /boot/initrd.img-${fk_kvers}
>>  > >  > >  > >     22231585 bytes read in 777 ms (27.3 MiB/s)
>>  > >  > >  > >     Odroid # env set bootargs console=ttySAC1,115200n8
>>  > >  > >  > >     Odroid # bootz ${kernel_addr_r}
>>  > >  > > ${ramdisk_addr_r}:${filesize}
>>  > >  > >  > >  ${fdt_addr_r}
>>  > >  > >  > >     Kernel image @ 0x41000000 [ 0x000000 - 0x4be200 ]
>>  > >  > >  > >     ## Flattened Device Tree blob at 40800000
>>  > >  > >  > >        Booting using the fdt blob at 0x40800000
>>  > >  > >  > >        Loading Ramdisk to b9947000, end bae7aa21 ... 
>> OK
>>  > >  > >  > >        Loading Device Tree to b9936000, end b99460bf 
>> ... OK
>>  > >  > >  > >
>>  > >  > >  > >     Starting kernel ...
>>  > >  > >  > >
>>  > >  > >  > >  And that's all I ever see. Normally the initrd loads 
>> a
>>  > > module
>>  > >  > > that
>>  > >  > >  > > causes an
>>  > >  > >  > >  LED on the Odroid to blink, and this is not happening
>>  > > either,
>>  > >  > > so
>>  > >  > >  > > I'm pretty
>>  > >  > >  > >  confident the kernel doesn't start or at least 
>> crashes
>>  > > before
>>  > >  > >  > > producing
>>  > >  > >  > >  output. If I set `initrd_high` to `0x50000000` (or
>>  > > something
>>  > >  > > in the
>>  > >  > >  > >  neighborhood) the kernel starts just fine:
>>  > >  > >  > >
>>  > >  > >  > >     U-Boot 2020.10-rc2-00314-g4963f63fe6 (Jan 09 2023 
>> -
>>  > > 23:59:31
>>  > >  > >  > > +0100)
>>  > >  > >  > >
>>  > >  > >  > >     CPU: Exynos4412 @ 1 GHz
>>  > >  > >  > >     Model: Odroid based on Exynos4412
>>  > >  > >  > >     Type: u3
>>  > >  > >  > >     DRAM: 2 GiB
>>  > >  > >  > >     LDO20@VDDQ_EMMC_1.8V: set 1800000 uV; enabling
>>  > >  > >  > >     LDO22@VDDQ_EMMC_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     LDO21@TFLASH_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     MMC: SAMSUNG SDHCI: 2, EXYNOS DWMMC: 0
>>  > >  > >  > >     Loading Environment from MMC... *** Warning - bad 
>> CRC,
>>  > > using
>>  > >  > >  > > default
>>  > >  > >  > >  environment
>>  > >  > >  > >
>>  > >  > >  > >     In: serial
>>  > >  > >  > >     Out: serial
>>  > >  > >  > >     Err: serial
>>  > >  > >  > >     Boot device: MMC(2)
>>  > >  > >  > >     Net: No ethernet found.
>>  > >  > >  > >     Hit any key to stop autoboot: 0
>>  > >  > >  > >     Odroid # env set fk_kvers 5.10.0-20-armmp
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > > ${fdt_addr_r}
>>  > >  > >  > >  /boot/dtbs/${fk_kvers}/exynos4412-odroidu3.dtb
>>  > >  > >  > >     53440 bytes read in 49 ms (1 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${kernel_addr_r}
>>  > >  > >  > >  /boot/vmlinuz-${fk_kvers}
>>  > >  > >  > >     4973056 bytes read in 181 ms (26.2 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${ramdisk_addr_r}
>>  > >  > >  > >  /boot/initrd.img-${fk_kvers}
>>  > >  > >  > >     22231585 bytes read in 777 ms (27.3 MiB/s)
>>  > >  > >  > >     Odroid # env set bootargs console=ttySAC1,115200n8
>>  > >  > >  > >     Odroid # env set initrd_high 0x50000000
>>  > >  > >  > >     Odroid # bootz ${kernel_addr_r}
>>  > >  > > ${ramdisk_addr_r}:${filesize}
>>  > >  > >  > >  ${fdt_addr_r}
>>  > >  > >  > >     Kernel image @ 0x41000000 [ 0x000000 - 0x4be200 ]
>>  > >  > >  > >     ## Flattened Device Tree blob at 40800000
>>  > >  > >  > >        Booting using the fdt blob at 0x40800000
>>  > >  > >  > >        Loading Ramdisk to 4eacc000, end 4ffffa21 ... 
>> OK
>>  > >  > >  > >        Loading Device Tree to bae6a000, end bae7a0bf 
>> ... OK
>>  > >  > >  > >
>>  > >  > >  > >     Starting kernel ...
>>  > >  > >  > >
>>  > >  > >  > >     [ 0.000000] Booting Linux on physical CPU 0xa00
>>  > >  > >  > >     <truncated>
>>  > >  > >  > >
>>  > >  > >  > >  The difference between those two runs is the location
>>  > > where
>>  > >  > > U-Boot
>>  > >  > >  > > loads the
>>  > >  > >  > >  initrd. The parent commit of 4963f63f boots fine 
>> without
>>  > >  > > setting
>>  > >  > >  > >  `initrd_high`:
>>  > >  > >  > >
>>  > >  > >  > >     U-Boot 2020.10-rc2-00313-gdfaf6a5797 (Jan 10 2023 
>> -
>>  > > 00:13:19
>>  > >  > >  > > +0100)
>>  > >  > >  > >
>>  > >  > >  > >     CPU: Exynos4412 @ 1 GHz
>>  > >  > >  > >     Model: Odroid based on Exynos4412
>>  > >  > >  > >     Type: u3
>>  > >  > >  > >     DRAM: 2 GiB
>>  > >  > >  > >     LDO20@VDDQ_EMMC_1.8V: set 1800000 uV; enabling
>>  > >  > >  > >     LDO22@VDDQ_EMMC_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     LDO21@TFLASH_2.8V: set 2800000 uV; enabling
>>  > >  > >  > >     MMC: SAMSUNG SDHCI: 2, EXYNOS DWMMC: 0
>>  > >  > >  > >     Loading Environment from MMC... *** Warning - bad 
>> CRC,
>>  > > using
>>  > >  > >  > > default
>>  > >  > >  > >  environment
>>  > >  > >  > >
>>  > >  > >  > >     In: serial
>>  > >  > >  > >     Out: serial
>>  > >  > >  > >     Err: serial
>>  > >  > >  > >     Boot device: MMC(2)
>>  > >  > >  > >     Net: No ethernet found.
>>  > >  > >  > >     Hit any key to stop autoboot: 0
>>  > >  > >  > >     Odroid # env set fk_kvers 5.10.0-20-armmp
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > > ${fdt_addr_r}
>>  > >  > >  > >  /boot/dtbs/${fk_kvers}/exynos4412-odroidu3.dtb
>>  > >  > >  > >     53440 bytes read in 49 ms (1 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${kernel_addr_r}
>>  > >  > >  > >  /boot/vmlinuz-${fk_kvers}
>>  > >  > >  > >     4973056 bytes read in 181 ms (26.2 MiB/s)
>>  > >  > >  > >     Odroid # load mmc ${mmcbootdev}:${mmcbootpart}
>>  > >  > > ${ramdisk_addr_r}
>>  > >  > >  > >  /boot/initrd.img-${fk_kvers}
>>  > >  > >  > >     22231585 bytes read in 776 ms (27.3 MiB/s)
>>  > >  > >  > >     Odroid # env set bootargs console=ttySAC1,115200n8
>>  > >  > >  > >     Odroid # bootz ${kernel_addr_r}
>>  > >  > > ${ramdisk_addr_r}:${filesize}
>>  > >  > >  > >  ${fdt_addr_r}
>>  > >  > >  > >     Kernel image @ 0x41000000 [ 0x000000 - 0x4be200 ]
>>  > >  > >  > >     ## Flattened Device Tree blob at 40800000
>>  > >  > >  > >        Booting using the fdt blob at 0x40800000
>>  > >  > >  > >        Loading Ramdisk to 4eacc000, end 4ffffa21 ... 
>> OK
>>  > >  > >  > >        Loading Device Tree to 4eabb000, end 4eacb0bf 
>> ... OK
>>  > >  > >  > >
>>  > >  > >  > >     Starting kernel ...
>>  > >  > >  > >
>>  > >  > >  > >     [ 0.000000] Booting Linux on physical CPU 0xa00
>>  > >  > >  > >     <truncated>
>>  > >  > >  > >
>>  > >  > >  > >  I've tested two different kernels from Debian 
>> (buster and
>>  > >  > > bullseye)
>>  > >  > >  > > and both
>>  > >  > >  > >  have the same problem. I'm building U-Boot using the
>>  > > default
>>  > >  > > config
>>  > >  > >  > > for
>>  > >  > >  > >  board `odroid` and boot the Odroid from an SD card 
>> with
>>  > >  > > firmware
>>  > >  > >  > > (`bl1`,
>>  > >  > >  > >  `bl2` and `tzsw`) from Hardkernel's clone of the 
>> u-boot
>>  > >  > > repository
>>  > >  > >  > > [1].
>>  > >  > >  > >  There are no peripherals connected apart from the SD 
>> card
>>  > > and
>>  > >  > > the
>>  > >  > >  > > serial
>>  > >  > >  > >  console. Please let me know if you need more 
>> information.
>>  > >  > >  >
>>  > >  > >  > Interesting. So what does "bdi" show, both in the older 
>> good
>>  > > and
>>  > >  > >  > then current tree? Specifically the information about 
>> where
>>  > > DRAM
>>  > >  > > is, and
>>  > >  > >  > how large it is? Thanks.
>>  > >  > >  >
>>  > >  > >  > --
>>  > >  > >  > Tom
>>  > >  > >
>>  > >  > >  Both 4963f63f (not working) and its parent (working) 
>> produce
>>  > > the
>>  > >  > > same
>>  > >  > >  output:
>>  > >  > >
>>  > >  > >     boot_params = 0x40000100
>>  > >  > >     DRAM bank   = 0x00000000
>>  > >  > >     -> start    = 0x40000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000001
>>  > >  > >     -> start    = 0x50000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000002
>>  > >  > >     -> start    = 0x60000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000003
>>  > >  > >     -> start    = 0x70000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000004
>>  > >  > >     -> start    = 0x80000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000005
>>  > >  > >     -> start    = 0x90000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000006
>>  > >  > >     -> start    = 0xa0000000
>>  > >  > >     -> size     = 0x10000000
>>  > >  > >     DRAM bank   = 0x00000007
>>  > >  > >     -> start    = 0xb0000000
>>  > >  > >     -> size     = 0x0ff00000
>>  > >  > >     memstart    = 0x40000000
>>  > >  > >     memsize     = 0x7ff00000
>>  > >  > >     flashstart  = 0x00000000
>>  > >  > >     flashsize   = 0x00000000
>>  > >  > >     flashoffset = 0x00000000
>>  > >  > >     baudrate    = 115200 bps
>>  > >  > >     relocaddr   = 0xbfe83000
>>  > >  > >     reloc off   = 0x7c083000
>>  > >  > >     Build       = 32-bit
>>  > >  > >     current eth = unknown
>>  > >  > >     ethaddr     = (not set)
>>  > >  > >     IP addr     = <NULL>
>>  > >  > >     fdt_blob    = 0xbae7bf00
>>  > >  > >     new_fdt     = 0xbae7bf00
>>  > >  > >     fdt_size    = 0x00002fa0
>>  > >  > >     lmb_dump_all:
>>  > >  > >         memory.cnt             = 0x1
>>  > >  > >         memory.size            = 0x0
>>  > >  > >         memory.reg[0x0].base   = 0x40000000
>>  > >  > >                        .size   = 0x7ff00000
>>  > >  > >
>>  > >  > >         reserved.cnt           = 0x1
>>  > >  > >         reserved.size          = 0x0
>>  > >  > >         reserved.reg[0x0].base = 0xbae7acd0
>>  > >  > >                          .size = 0x5085330
>>  > >  > >     arch_number = 0x000010c1
>>  > >  > >     TLB addr    = 0xbfef0000
>>  > >  > >     irq_sp      = 0xbae7bef0
>>  > >  > >     sp start    = 0xbae7bee0
>>  > >  > >     Board Type  = 0
>>  > >  > >     Early malloc usage: f0 / 400
>>  > >  > >
>>  > >  > >  I'm not sure if this is relevant, but with the failing 
>> commit
>>  > > I can
>>  > >  > > get the
>>  > >  > >  kernel to start with `initrd_high` set to `0x70000000` or
>>  > > lower,
>>  > >  > > but not
>>  > >  > >  higher.
>>  > >  >
>>  > >  > OK, so 8 whole banks, of 256MB each. Does this platform have 
>> 2GB
>>  > > of
>>  > >  > memory for real?
>>  > >  >
>>  > >  > --
>>  > >  > Tom
>>  > >
>>  > >  Yes, it does. See https://www.hardkernel.com/shop/odroid-u3/ .
>>  >
>>  > Thanks. I guess my current thought is that in the absence of 
>> adding
>>  > earlycon to the kernel args, to perhaps get more info out of the 
>> kernel
>>  > as to when / where it's dying, that bootm_size should be set to
>>  > 0x10000000 (256MB) to replicate the old behavior, on this 
>> platform.
>>  > Jaehoon, do you have any other ideas?
>>  >
>>  > --
>>  > Tom
>> 
>>  I was not aware of the existence of `earlycon`. Running the first 
>> failing
>>  commit 4963f63f with `earlycon` and with `initrd_high` *unset* 
>> reveals a
>>  kernel panic:
>> 
>>     Kernel image @ 0x41000000 [ 0x000000 - 0x4be200 ]
>>     ## Flattened Device Tree blob at 40800000
>>        Booting using the fdt blob at 0x40800000
>>        Loading Ramdisk to b9947000, end bae7aa21 ... OK
>>        Loading Device Tree to b9936000, end b99460bf ... OK
>> 
>>     Starting kernel ...
>> 
>>     [    0.000000] Booting Linux on physical CPU 0xa00
>>     [    0.000000] Linux version 5.10.0-20-armmp
>>  (debian-kernel@lists.debian.org) (gcc-10 (Debian 10.2.1-6) 10.2.1 
>> 20210110,
>>  GNU ld (GNU Binutils for Debian) 2.35.2) #1 SMP Debian 5.10.158-2
>>  (2022-12-13)
>>     [    0.000000] CPU: ARMv7 Processor [413fc090] revision 0 
>> (ARMv7),
>>  cr=10c5387d
>>     [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT 
>> aliasing
>>  instruction cache
>>     [    0.000000] OF: fdt: Machine model: Hardkernel ODROID-U3 
>> board based
>>  on Exynos4412
>>     [    0.000000] earlycon: exynos4210 at MMIO 0x13810000 (options 
>> '')
>>     [    0.000000] printk: bootconsole [exynos4210] enabled
>>     [    0.000000] Memory policy: Data cache writealloc
>>     [    0.000000] efi: UEFI not found.
>>     [    0.000000] Reserved memory: created DMA memory pool at 
>> 0xbf700000,
>>  size 8 MiB
>>     [    0.000000] OF: reserved mem: initialized node 
>> region_mfc_right,
>>  compatible id shared-dma-pool
>>     [    0.000000] Reserved memory: created DMA memory pool at 
>> 0xbd300000,
>>  size 36 MiB
>>     [    0.000000] OF: reserved mem: initialized node 
>> region_mfc_left,
>>  compatible id shared-dma-pool
>>     [    0.000000] cma: Reserved 16 MiB at 0xbc000000
>>     [    0.000000] Samsung CPU ID: 0xe4412220
>>     [    0.000000] Zone ranges:
>>     [    0.000000]   DMA      [mem 
>> 0x0000000040000000-0x000000006fffffff]
>>     [    0.000000]   Normal   empty
>>     [    0.000000]   HighMem  [mem 
>> 0x0000000070000000-0x00000000bd2fffff]
> 
> So here we go. Initrd cannot be in highmem. I cannot find this
> documented, quickly, under https://www.kernel.org/doc/html/latest/ so 
> I
> guess this is more just background knowledge than formal knowledge. 
> This
> also matches up with your noting that initrd_high=0x70000000 works.
> 
> --
> Tom

I found this [1]. Section 5 mentions placing the initrd in lowmem, if I 
understand everything correctly.

Setting `bootm_size` to ` 0x10000000` works for me. I can write a patch 
that adds `bootm_size=0x100000000` to `CFG_EXTRA_ENV_SETTINGS` in 
`include/configs/odroid.h` if you want, but I don't understand the fix, 
high mem and low mem well enough to write a decent commit message. I 
can certainly test (a backport of, see bug reports [2], [3]) a patch.

Thanks for identifying the problem and proposing a fix!

Best, Joost

PS: I didn't subscribe to the mailing list, so if someone sends a 
patch, please CC me.

[1]: https://www.kernel.org/doc/Documentation/arm/booting.rst
[2]: https://lists.denx.de/pipermail/u-boot/2023-January/504115.html
[3]: https://lists.denx.de/pipermail/u-boot/2023-January/504116.html



  reply	other threads:[~2023-01-11 21:10 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-10  8:13 kernel doesn't start on Odroid U2 unless setting initrd_high Joost van Zwieten
2023-01-10 18:41 ` Tom Rini
2023-01-10 23:01   ` Joost van Zwieten
2023-01-10 23:08     ` Tom Rini
2023-01-10 23:10       ` Joost van Zwieten
2023-01-10 23:29         ` Tom Rini
2023-01-11 20:28           ` Joost van Zwieten
2023-01-11 20:38             ` Tom Rini
2023-01-11 21:08               ` Joost van Zwieten [this message]
2023-01-12  0:10                 ` Tom Rini
2023-01-12 22:32                   ` Joost van Zwieten
2023-01-13 15:01                     ` Tom Rini

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