[PATCH v4] drivers/soc/litex: Add restart handler
Geert Uytterhoeven
geert at linux-m68k.org
Wed Jan 20 03:20:39 EST 2021
Hi Stafford,
On Tue, Jan 19, 2021 at 11:11 PM Stafford Horne <shorne at gmail.com> wrote:
> On Wed, Jan 20, 2021 at 06:34:44AM +0900, Stafford Horne wrote:
> > On Tue, Jan 19, 2021 at 09:09:38AM +0100, Geert Uytterhoeven wrote:
> > > Let the LiteX SoC Controller register a restart handler, which resets
> > > the LiteX SoC by writing 1 to CSR_CTRL_RESET_ADDR.
> > >
> > > Signed-off-by: Geert Uytterhoeven <geert at linux-m68k.org>
> >
> > Thanks, this looks good to me, queued to my linux-next branch.
> >
> > -Stafford
> >
> > > @@ -66,8 +71,19 @@ static int litex_check_csr_access(void __iomem *reg_addr)
> > >
> > > struct litex_soc_ctrl_device {
> > > void __iomem *base;
> > > + struct notifier_block reset_nb;
> > > };
> > >
> > > +static int litex_reset_handler(struct notifier_block *this, unsigned long mode,
> > > + void *cmd)
> > > +{
> > > + struct litex_soc_ctrl_device *soc_ctrl_dev =
> > > + container_of(this, struct litex_soc_ctrl_device, reset_nb);
> >
> > Nice.
> >
> > > + litex_write32(soc_ctrl_dev->base + RESET_REG_OFF, RESET_REG_VALUE);
> > > + return NOTIFY_DONE;
> > > +}
> > > +
>
> Actually, I tested this out on the latest (2-weeks ago) Litex and
> openrisc/for-next and it didn't seem to work correctly.
>
> I will look into it a bit closer, but if you see or can think of anything let
> me know. Note There are a few failures below related to network services as my
> for-next kernel doesnt have a network driver (yet).
Hmmm, openrisc/for-next does have commit 131172a4a8ce3fcc ("openrisc:
restart: Call common handlers before hanging").
It's been a few years I used an OpenRISC setup.
Do you have a link to Linux on mor1kx/LiteX setup instructions?
>
> Using my buildroot rootfs: http://shorne.noip.me/downloads/or1k-glibc-rootfs.cpio.gz
>
> # shutdown -r now
>
> Broadcast message from root at buildroot (console) (Thu Jan 1 00:00:48 1970):
> The system is going down for reboot NOW!
> INIT: Switching to runlevel: 6
> # mounting home work nfs ...
> mount: mounting 10.0.0.27:/home/shorne/work on /home/shorne/work failed: No such device
> enabling login for shorne ...
> setting coredumps ...
> Stopping dropbear sshd: FAIL
> Stopping ntpd: FAIL
> Nothing to do, sntp is not a daemon.
> Stopping network: ifdown: interface lo not configured
> ifdown: interface eth0 not configured
> OK
> Saving random seed: [ 52.020000] random: dd: uninitialized urandom read (512 bytes read)
> OK
> Stopping klogd: OK
> Stopping syslogd: start-stop-daemon: warning: killing process 51: No such process
> FAIL
> umount: devtmpfs busy - remounted read-only
> umount: can't unmount /: Invalid argument
> [ 53.710000] reboot: Restarting system
> [ 54.710000] Reboot failed -- System halted
> [ 76.040000] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [reboot:131]
> [ 76.040000] CPU: 0 PID: 131 Comm: reboot Not tainted 5.11.0-rc1-00009-gff28dae0bc90 #418
> [ 76.040000] CPU #: 0
> [ 76.040000] PC: c00050b8 SR: 0000827f SP: c180fdb0
> [ 76.040000] GPR00: 00000000 GPR01: c180fdb0 GPR02: c180fdc0 GPR03: 0000827f
> [ 76.040000] GPR04: c0348944 GPR05: 00000000 GPR06: c180fc70 GPR07: 00000000
> [ 76.040000] GPR08: c180fdb0 GPR09: c00050b8 GPR10: c180e000 GPR11: 0000001e
> [ 76.040000] GPR12: 00000000 GPR13: 00000020 GPR14: 00000001 GPR15: 00000000
> [ 76.040000] GPR16: 00000000 GPR17: c02e48d4 GPR18: 00418958 GPR19: c02e48d4
> [ 76.040000] GPR20: 00000000 GPR21: 00000000 GPR22: c02e4018 GPR23: fffffffe
> [ 76.040000] GPR24: ffffffff GPR25: 00000000 GPR26: 00000000 GPR27: 00000000
> [ 76.040000] GPR28: 00000000 GPR29: ffffffff GPR30: 00000000 GPR31: ffffffff
> [ 76.040000] RES: 0000001e oGPR11: ffffffff
> [ 76.040000] Process reboot (pid: 131, stackpage=c180a000)
> [ 76.040000]
> [ 76.040000] Stack:
> [ 76.040000] Call trace:
> [ 76.040000] [<(ptrval)>] machine_restart+0x44/0x5c
> [ 76.040000] [<(ptrval)>] kernel_restart+0x78/0xa4
> [ 76.040000] [<(ptrval)>] ? mutex_lock+0x24/0x50
> [ 76.040000] [<(ptrval)>] __do_sys_reboot+0x1a8/0x21c
> [ 76.040000] [<(ptrval)>] ? do_filp_open+0x40/0xa0
> [ 76.040000] [<(ptrval)>] ? slab_free_freelist_hook+0x6c/0x14c
> [ 76.040000] [<(ptrval)>] ? arch_local_irq_save+0x24/0x3c
> [ 76.040000] [<(ptrval)>] ? kmem_cache_free+0x130/0x194
> [ 76.040000] [<(ptrval)>] ? call_rcu+0x50/0x8c
> [ 76.040000] [<(ptrval)>] ? __fput+0x2d0/0x2f4
> [ 76.040000] [<(ptrval)>] ? do_sys_openat2+0xd8/0x134
> [ 76.040000] [<(ptrval)>] ? task_work_run+0xbc/0xf4
> [ 76.040000] [<(ptrval)>] ? do_work_pending+0x60/0x12c
> [ 76.040000] [<(ptrval)>] sys_reboot+0x14/0x24
> [ 76.040000] [<(ptrval)>] ? _syscall_return+0x0/0x4
>
>
> -Stafford
--
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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