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From: Carlos Eduardo de Paula <me@carlosedp.com>
To: Damien Le Moal <damien.lemoal@wdc.com>
Cc: linux-riscv <linux-riscv@lists.infradead.org>,
	Anup Patel <Anup.Patel@wdc.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Paul Walmsley <paul.walmsley@sifive.com>
Subject: Re: [PATCH 00/10] Kendryte k210 SoC boards support
Date: Fri, 14 Feb 2020 12:05:51 -0300	[thread overview]
Message-ID: <CADnnUqcFbmspQ0fcggoyPTE4mckoGahHmaNdcJeC7GJD7C16uA@mail.gmail.com> (raw)
In-Reply-To: <20200212103432.660256-1-damien.lemoal@wdc.com>

On Wed, Feb 12, 2020 at 7:34 AM Damien Le Moal <damien.lemoal@wdc.com> wrote:
>
> This series adds support to boot nommu Linux on Kendryte K210 SoC based
> boards. This is all based on initial work done by Christoph Hellwig.
>
> The first 2 patches fix riscv gitignore and a potential nommu
> compilation error. These patches are not specific to the Kendryte
> support.
>
> Patch 3 adds unaligned load/store trap handlers for M-mode.
>
> Patch 4 enables a builtin DTB to allow passing a device tree to the
> kernel when the board bootchain is enabled to pass one.
>
> Patch 5 introduces an early SoC initialization enabling very early
> hardware initialization not possible with device tree entries pointing
> to drivers. This is used in patch 6 which introduces a sysctl driver for
> the K210 SoC. The early SoC initialization is used to enable the
> additional 2MB of SRAM normally reserved to the SoC AI chip.
>
> Patch 7 to 9 add necessary Kconfig changes, a defconfig and a generic
> device tree suitable for many K210 boards.
>
> Finally, patch 10 adds compilation of a bootable image file (bin file)
> that can be used to flash the board ROM.
>
> This series was tested on the Kendryte KD233 development board, the
> Sipeed MAIX dan dock board and the Sipeed MAIXDUINO board. The userspace
> used was built using a modified buildroot tree for the toolchain part
> and an unmodified busybox tree for the initramfs image (embedded in the
> kernel as a cpio file). The folowwing github project contains the
> modified buildroot tree:
>
> https://github.com/damien-lemoal/riscv64-nommu-buildroot
>
> This is based on work from Christoph Hellwig, with additional changes
> and updates to the latest upstream versions for buildroot and uClibc.
>
> Precompiled versions of the toolchain (gcc 9.2) and initramfs file tree
> and cpio file can be found in this project under the directory:
>
> buildroot/riscv64-uclibc-nommu/
>
> Flashing the file arch/riscv/boot/loader.bin to a board can be done
> using the Sipeed kflash.py tool with the command:
>
> kflash.py/kflash.py -p /dev/ttyUSB0 -b 1500000 -t loader.bin
>
> The kflash.py tool can be found here:
>
> https://github.com/sipeed/kflash.py
>
> For reference, using the Sipeed MAIXDUINO board, here is the boot
> output:
>
> [INFO] Rebooting...
> --- forcing DTR inactive
> --- forcing RTS inactive
> --- Miniterm on /dev/ttyUSB0  115200,8,N,1 ---
> --- Quit: Ctrl+] | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H ---
> [    0.000000] Linux version 5.6.0-rc1-00011-ga2b5be1c4374 (damien@yyy) (gcc version 8.2.0 (Buildroot 2018.11-rc2-00003-ga0787e9)) #610 SMP Wed Feb 12 18:53:50 JST 2020
> [    0.000000] earlycon: sifive0 at MMIO 0x0000000038000000 (options '')
> [    0.000000] printk: bootconsole [sifive0] enabled
> [    0.000000] initrd not found or empty - disabling initrd
> [    0.000000] Zone ranges:
> [    0.000000]   DMA32    [mem 0x0000000080000000-0x00000000807fffff]
> [    0.000000]   Normal   empty
> [    0.000000] Movable zone start for each node
> [    0.000000] Early memory node ranges
> [    0.000000]   node   0: [mem 0x0000000080000000-0x00000000807fffff]
> [    0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x00000000807fffff]
> [    0.000000] elf_hwcap is 0x112d
> [    0.000000] percpu: max_distance=0x18000 too large for vmalloc space 0x0
> [    0.000000] percpu: Embedded 12 pages/cpu s18272 r0 d30880 u49152
> [    0.000000] Built 1 zonelists, mobility grouping off.  Total pages: 2020
> [    0.000000] Kernel command line: earlycon console=ttySIF0
> [    0.000000] Dentry cache hash table entries: 1024 (order: 1, 8192 bytes, linear)
> [    0.000000] Inode-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
> [    0.000000] Sorting __ex_table...
> [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> [    0.000000] Memory: 6328K/8192K available (924K kernel code, 110K rwdata, 164K rodata, 321K init, 91K bss, 1864K reserved, 0K cma-reserved)
> [    0.000000] rcu: Hierarchical RCU implementation.
> [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> [    0.000000] NR_IRQS: 0, nr_irqs: 0, preallocated irqs: 0
> [    0.000000] plic: mapped 65 interrupts with 2 handlers for 4 contexts.
> [    0.000000] riscv_timer_init_dt: Registering clocksource cpuid [0] hartid [0]
> [    0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x3990be68b, max_idle_ns: 881590404272 ns
> [    0.000014] sched_clock: 64 bits at 7MHz, resolution 128ns, wraps every 4398046511054ns
> [    0.008232] Console: colour dummy device 80x25
> [    0.012474] Calibrating delay loop (skipped), value calculated using timer frequency.. 15.60 BogoMIPS (lpj=31200)
> [    0.022678] pid_max: default: 4096 minimum: 301
> [    0.027288] Mount-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
> [    0.034414] Mountpoint-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
> [    0.044796] rcu: Hierarchical SRCU implementation.
> [    0.049602] smp: Bringing up secondary CPUs ...
> [    0.054746] smp: Brought up 1 node, 2 CPUs
> [    0.059093] devtmpfs: initialized
> [    0.065523] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
> [    0.074544] futex hash table entries: 16 (order: -2, 1024 bytes, linear)
> [    0.082512] Kendryte K210 SoC sysctl
> [    0.096010] clocksource: Switched to clocksource riscv_clocksource
> [    0.178581] workingset: timestamp_bits=62 max_order=11 bucket_order=0
> [    0.185846] 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 0) is a SiFive UART v0
> [    0.194344] printk: console [ttySIF0] enabled
> [    0.194344] printk: console [ttySIF0] enabled
> [    0.202929] printk: bootconsole [sifive0] disabled
> [    0.202929] printk: bootconsole [sifive0] disabled
> [    0.214853] random: get_random_bytes called from 0x0000000080055178 with crng_init=0
> [    0.223606] devtmpfs: mounted
> [    0.226861] Freeing unused kernel memory: 320K
> [    0.230574] This architecture does not have kernel memory protection.
> [    0.236987] Run /sbin/init as init process
> [    0.241181] Run /etc/init as init process
> [    0.245178] Run /bin/init as init process
>
> -----------------------------
> | Kendryte K210 NOMMU Linux |
> -----------------------------
> Mounting /proc
> Starting shell
>
>
> BusyBox v1.32.0.git (2020-02-12 17:51:45 JST) hush - the humble shell
> Enter 'help' for a list of built-in commands.
>
> / # cat /proc/cpuinfo
> processor       : 0
> hart            : 0
> isa             : rv64imafdc
>
> processor       : 1
> hart            : 1
> isa             : rv64imafdc
>
> / #
> / # ls -l /
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 bin
> drwxr-xr-x    2 0        0                0 Jan  1 00:00 dev
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 etc
> dr-xr-xr-x   58 0        0                0 Jan  1 00:00 proc
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 root
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 sbin
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 sys
> drwxrwxr-x    2 1000     1000             0 Feb 12  2020 tmp
> drwxrwxr-x    4 1000     1000             0 Feb 12  2020 usr
> / #
> / # cat /proc/vmstat
> nr_free_pages 1148
> ...
> / #
>
> The K210 SoC has more devices (GPIO, SD-card, LCD, etc) that likely can
> be enabled and used. For this, the sysctl driver will need further
> improvements as each device uses a different clock. To share the fun,
> supporting these is left as an exercise for the hobbyist and hackers
> interested in this SoC/boards :)
>
> Christoph Hellwig (2):
>   riscv: Add Kendryte K210 SoC support
>   riscv: create a loader.bin for the kendryte kflash.py tool
>
> Damien Le Moal (8):
>   riscv: Fix gitignore
>   riscv: Force flat memory model with no-mmu
>   riscv: Unaligned load/store handling for M_MODE
>   riscv: Add BUILTIN_DTB support
>   riscv: Add SOC early init support
>   riscv: Select required drivers for Kendryte SOC
>   riscv: Add Kendryte K210 device tree
>   riscv: Kendryte K210 default config
>
>  arch/riscv/Kbuild                       |   1 +
>  arch/riscv/Kconfig                      |  19 ++
>  arch/riscv/Kconfig.socs                 |  10 +
>  arch/riscv/Makefile                     |   4 +-
>  arch/riscv/boot/.gitignore              |   2 +
>  arch/riscv/boot/Makefile                |   3 +
>  arch/riscv/boot/dts/Makefile            |   5 +
>  arch/riscv/boot/dts/kendryte/Makefile   |   2 +
>  arch/riscv/boot/dts/kendryte/k210.dts   |  23 ++
>  arch/riscv/boot/dts/kendryte/k210.dtsi  | 123 ++++++++
>  arch/riscv/configs/nommu_k210_defconfig |  68 +++++
>  arch/riscv/include/asm/soc.h            |  23 ++
>  arch/riscv/kernel/Makefile              |   3 +-
>  arch/riscv/kernel/head.S                |   1 +
>  arch/riscv/kernel/setup.c               |   6 +
>  arch/riscv/kernel/soc.c                 |  28 ++
>  arch/riscv/kernel/traps.c               |  27 +-
>  arch/riscv/kernel/traps_misaligned.c    | 371 ++++++++++++++++++++++++
>  arch/riscv/kernel/vmlinux.lds.S         |   6 +
>  arch/riscv/mm/init.c                    |   4 +
>  drivers/soc/Kconfig                     |   1 +
>  drivers/soc/Makefile                    |   1 +
>  drivers/soc/kendryte/Kconfig            |  14 +
>  drivers/soc/kendryte/Makefile           |   3 +
>  drivers/soc/kendryte/k210-sysctl.c      | 245 ++++++++++++++++
>  25 files changed, 987 insertions(+), 6 deletions(-)
>  create mode 100644 arch/riscv/boot/dts/kendryte/Makefile
>  create mode 100644 arch/riscv/boot/dts/kendryte/k210.dts
>  create mode 100644 arch/riscv/boot/dts/kendryte/k210.dtsi
>  create mode 100644 arch/riscv/configs/nommu_k210_defconfig
>  create mode 100644 arch/riscv/include/asm/soc.h
>  create mode 100644 arch/riscv/kernel/soc.c
>  create mode 100644 arch/riscv/kernel/traps_misaligned.c
>  create mode 100644 drivers/soc/kendryte/Kconfig
>  create mode 100644 drivers/soc/kendryte/Makefile
>  create mode 100644 drivers/soc/kendryte/k210-sysctl.c
>
> --
> 2.24.1
>
>

Hi Damien, I've tested the patches on v5.5.0 and it boots perfectly on
my MaixGo board. I used the provided initramfs.cpio as the payload and
got to the busybox prompt.

While trying to build my own busybox, I got a few problems. I've
checked-out your tree and copied the toolchain. Then when building
busybox with your minimal config, I got this error:

  LINK    busybox_unstripped
Your linker does not support --sort-section,alignment
Your linker does not support --sort-common
Your linker does not support -Wl,--gc-sections
Trying libraries: m rt
Failed: -Wl,--start-group  -lm -lrt  -Wl,--end-group
Output of:
/opt/riscv64-uclibc/bin/riscv64-linux-gcc -Wall -Wshadow
-Wwrite-strings -Wundef -Wstrict-prototypes -Wunused
-Wunused-parameter -Wunused-function -Wunused-value
-Wmissing-prototypes -Wmissing-declarations -Wno-format-security
-Wdeclaration-after-statement -Wold-style-definition -finline-limit=0
-fno-builtin-strlen -fomit-frame-pointer -ffunction-sections
-fdata-sections -fno-guess-branch-probability -funsigned-char
-static-libgcc -falign-functions=1 -falign-jumps=1 -falign-labels=1
-falign-loops=1 -fno-unwind-tables -fno-asynchronous-unwind-tables
-fno-builtin-printf -Wno-string-plus-int -Wno-constant-logical-operand
-Os -Os -fPIC --sysroot=/opt/riscv64-uclibc/riscv64-buildroot-linux-uclibc/sysroot/
-static -Os -static -Wl,-elf2flt=-r -o busybox_unstripped
-Wl,--start-group applets/built-in.o archival/lib.a
archival/libarchive/lib.a console-tools/lib.a coreutils/lib.a
coreutils/libcoreutils/lib.a debianutils/lib.a klibc-utils/lib.a
e2fsprogs/lib.a editors/lib.a findutils/lib.a init/lib.a libbb/lib.a
libpwdgrp/lib.a loginutils/lib.a mailutils/lib.a miscutils/lib.a
modutils/lib.a networking/lib.a networking/libiproute/lib.a
networking/udhcp/lib.a printutils/lib.a procps/lib.a runit/lib.a
selinux/lib.a shell/lib.a sysklogd/lib.a util-linux/lib.a
util-linux/volume_id/lib.a archival/built-in.o
archival/libarchive/built-in.o console-tools/built-in.o
coreutils/built-in.o coreutils/libcoreutils/built-in.o
debianutils/built-in.o klibc-utils/built-in.o e2fsprogs/built-in.o
editors/built-in.o findutils/built-in.o init/built-in.o
libbb/built-in.o libpwdgrp/built-in.o loginutils/built-in.o
mailutils/built-in.o miscutils/built-in.o modutils/built-in.o
networking/built-in.o networking/libiproute/built-in.o
networking/udhcp/built-in.o printutils/built-in.o procps/built-in.o
runit/built-in.o selinux/built-in.o shell/built-in.o
sysklogd/built-in.o util-linux/built-in.o
util-linux/volume_id/built-in.o -Wl,--end-group -Wl,--start-group -lm
-lrt -Wl,--end-group
==========
/opt/riscv64-uclibc/riscv64-buildroot-linux-uclibc/bin/ld.real: cannot
find crt1.o: No such file or directory
/opt/riscv64-uclibc/riscv64-buildroot-linux-uclibc/bin/ld.real: cannot
find crti.o: No such file or directory
/opt/riscv64-uclibc/riscv64-buildroot-linux-uclibc/bin/ld.real: cannot
find crtbeginT.o: No such file or directory
collect2: error: ld returned 1 exit status
Note: if build needs additional libraries, put them in CONFIG_EXTRA_LDLIBS.
Example: CONFIG_EXTRA_LDLIBS="pthread dl tirpc audit pam"
make: *** [Makefile:718: busybox_unstripped] Error 1

Then I've built the complete buildroot toolchain and replaced it on /opt.

Then I've proceeded to "make SKIP_STRIP=y" and "make install" and it
built fine. I got into _install dir and ran: "find . | sudo cpio -H
newc --create --verbose > ../k210.cpio" to generate the cpio. All this
with the

Rebuilt the kernel with it but when booting, I got this error:

[    0.259289] Run /sbin/init as init process
[    0.263480] Run /etc/init as init process
[    0.267453] Run /bin/init as init process
[    0.286973] Kernel panic - not syncing: Attempted to kill init!
exitcode=0x00000000
[    0.293869] CPU: 1 PID: 1 Comm: sh Not tainted 5.5.0-dirty #19
[    0.299673] Call Trace:
[    0.302109] [<00000000800401f6>] 0x00000000800401f6
[    0.306969] [<000000008004033a>] 0x000000008004033a
[    0.311831] [<0000000080111abe>] 0x0000000080111abe
[    0.316693] [<000000008004340e>] 0x000000008004340e
[    0.321556] [<0000000080045402>] 0x0000000080045402
[    0.326417] [<0000000080045898>] 0x0000000080045898
[    0.331279] [<000000008003f1d2>] 0x000000008003f1d2
[    0.336142] SMP: stopping secondary CPUs
[    0.340065] ---[ end Kernel panic - not syncing: Attempted to kill
init! exitcode=0x00000000 ]---

I also tried with a gzipped cpio but got the "Kernel panic - not
syncing: no cpio magic" error.

What's the right way to create the cpio initramfs? I want to customize
it a little.

Thanks.

-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
http://twitter.com/carlosedp
Linkedin
________________________________________


  parent reply	other threads:[~2020-02-14 15:06 UTC|newest]

Thread overview: 89+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-12 10:34 [PATCH 00/10] Kendryte k210 SoC boards support Damien Le Moal
2020-02-12 10:34 ` [PATCH 01/10] riscv: Fix gitignore Damien Le Moal
2020-02-20  0:15   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 02/10] riscv: Force flat memory model with no-mmu Damien Le Moal
2020-02-14 20:18   ` Sean Anderson
2020-02-15  2:15     ` Damien Le Moal
2020-02-15  2:26       ` Sean Anderson
2020-02-15  2:40         ` Damien Le Moal
2020-03-02  3:48   ` Anup Patel
2020-03-04 18:38   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 03/10] riscv: Unaligned load/store handling for M_MODE Damien Le Moal
2020-03-02  3:57   ` Anup Patel
2020-03-04 19:28   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 04/10] riscv: Add BUILTIN_DTB support Damien Le Moal
2020-03-02  3:58   ` Anup Patel
2020-03-04 19:28   ` Palmer Dabbelt
2020-03-05  4:58     ` Anup Patel
2020-03-05  5:14       ` Damien Le Moal
2020-03-05  5:37         ` Anup Patel
2020-03-05  6:13           ` Damien Le Moal
2020-03-08  6:10             ` Anup Patel
2020-03-05  8:18         ` Atish Patra
2020-03-07  0:02           ` Sean Anderson
2020-03-07  1:51             ` Atish Patra
2020-03-07  2:08               ` Sean Anderson
2020-03-06 23:56         ` Sean Anderson
2020-02-12 10:34 ` [PATCH 05/10] riscv: Add SOC early init support Damien Le Moal
2020-03-04 19:28   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 06/10] riscv: Add Kendryte K210 SoC support Damien Le Moal
2020-02-14 20:31   ` Sean Anderson
2020-03-04 19:38   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 07/10] riscv: Select required drivers for Kendryte SOC Damien Le Moal
2020-03-02  3:59   ` Anup Patel
2020-03-04 19:44   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 08/10] riscv: Add Kendryte K210 device tree Damien Le Moal
2020-02-14 20:51   ` Sean Anderson
2020-02-15  2:34     ` Damien Le Moal
2020-02-15  2:48       ` Sean Anderson
2020-02-15  3:00         ` Damien Le Moal
2020-02-18 14:12           ` Carlos Eduardo de Paula
2020-02-18 14:18             ` Sean Anderson
2020-02-18 14:30               ` Carlos Eduardo de Paula
2020-02-18 17:48                 ` Sean Anderson
2020-02-18 19:26                   ` Carlos Eduardo de Paula
2020-02-19  9:06                     ` Wladimir J. van der Laan
2020-02-19 22:28                       ` Sean Anderson
2020-02-20 10:48                         ` Wladimir J. van der Laan
2020-02-22 19:07                       ` Wladimir J. van der Laan
2020-04-01 17:55                         ` Drew Fustini
2020-04-02  2:24                           ` Damien Le Moal
2020-02-19  8:50                   ` Wladimir J. van der Laan
2020-02-27 19:43       ` Sean Anderson
2020-03-02  4:06   ` Anup Patel
2020-03-02  4:15     ` Damien Le Moal
2020-03-02  4:22       ` Anup Patel
2020-03-02  4:51         ` Damien Le Moal
2020-03-02  5:05           ` Anup Patel
2020-03-02  5:08             ` Damien Le Moal
2020-03-07  0:18               ` Sean Anderson
2020-03-07  4:11                 ` Anup Patel
2020-03-04 19:44   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 09/10] riscv: Kendryte K210 default config Damien Le Moal
2020-03-02  4:07   ` Anup Patel
2020-03-04 19:44   ` Palmer Dabbelt
2020-02-12 10:34 ` [PATCH 10/10] riscv: create a loader.bin for the kendryte kflash.py tool Damien Le Moal
2020-03-02  4:08   ` Anup Patel
2020-03-04 19:44   ` Palmer Dabbelt
2020-02-14 15:05 ` Carlos Eduardo de Paula [this message]
2020-02-15  2:02   ` [PATCH 00/10] Kendryte k210 SoC boards support Damien Le Moal
2020-02-17 13:28     ` Carlos Eduardo de Paula
2020-02-26 21:31       ` Carlos Eduardo de Paula
2020-02-27  2:18         ` Damien Le Moal
2020-02-28 20:32 ` Sean Anderson
2020-03-02  3:01   ` Damien Le Moal
2020-03-02  3:53     ` Sean Anderson
2020-03-02  4:11       ` Damien Le Moal
2020-03-02  4:18         ` Sean Anderson
2020-03-02  4:54           ` Damien Le Moal
2020-03-02  4:56             ` Sean Anderson
2020-03-02  5:03               ` Damien Le Moal
2020-03-02  4:17       ` Anup Patel
2020-03-02  4:21         ` Sean Anderson
2020-03-02  4:48         ` Damien Le Moal
2020-03-02  4:51           ` Damien Le Moal
2020-03-02  5:02           ` Sean Anderson
2020-03-02  5:11             ` Damien Le Moal
2020-03-02  5:25               ` Sean Anderson
2020-03-02  5:43                 ` Damien Le Moal
2020-03-04 19:44 ` Palmer Dabbelt

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