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Re: [Qemu-devel] [PATCH v6 07/24] hw/arm: add Faraday FTWDT010 watchdog
From: |
Paolo Bonzini |
Subject: |
Re: [Qemu-devel] [PATCH v6 07/24] hw/arm: add Faraday FTWDT010 watchdog timer support |
Date: |
Wed, 6 Mar 2013 05:46:25 -0500 (EST) |
> > > It doesn't work while running under ROM mode. ( no -kernel )
> > > Because Faraday SoC Platform usually designed to boot from ROM and
> > > followed by an AHB remapping process (i.e. remap ROM/RAM address).
> >
> > What doesn't work exactly? Why aren't these called? Or are
> > you forcing a particular reset order?
> >
> > Paolo
>
> While booting from ROM, the faraday soc usually remap the ROM / RAM
> before jumping into linux.
>
> In other words, the system mapping is:
>
> 1. Power-On:
>
> ROM: 0x00000000
> RAM: N/A
> SRAM: 0xA0000000
>
> 2. AHB Remap (u-boot/linux)
>
> ROM: 0x20000000
> RAM: 0x00000000
>
> So I have to register my own reset handler to
>
> 1. Undo the ROM/RAM remap (i.e. device_reset(s->ahbc))
> 2. Reset CPU
----- Messaggio originale -----
> Da: "Kuo-Jung Su" <address@hidden>
> A: "Paolo Bonzini" <address@hidden>
> Inviato: Mercoledì, 6 marzo 2013 11:00:49
> Oggetto: Re: [PATCH v6 07/24] hw/arm: add Faraday FTWDT010 watchdog timer
> support
>
> 2013/3/6 Paolo Bonzini <address@hidden>:
> >
> >> 2013/3/6 Paolo Bonzini <address@hidden>:
> >> > Il 06/03/2013 08:27, Kuo-Jung Su ha scritto:
> >> >> The FTWDT010 is used to prevent system from infinite loop
> >> >> while software gets trapped in the deadlock.
> >> >>
> >> >> Under the normal operation, users should restart FTWDT010
> >> >> at the regular intervals before counter counts down to 0.
> >> >>
> >> >> If the counter does reach 0, FTWDT010 will try to reset
> >> >> the system by generating one or a combination of signals,
> >> >> system reset, system interrupt, and external interrupt.
> >> >>
> >> >> Signed-off-by: Kuo-Jung Su <address@hidden>
> >> >> ---
> >> >> hw/arm/Makefile.objs | 1 +
> >> >> hw/arm/faraday_a369_soc.c | 23 +++++
> >> >> hw/arm/ftwdt010.c | 212
> >> >> +++++++++++++++++++++++++++++++++++++++++++++
> >> >> hw/arm/ftwdt010.h | 35 ++++++++
> >> >> 4 files changed, 271 insertions(+)
> >> >> create mode 100644 hw/arm/ftwdt010.c
> >> >> create mode 100644 hw/arm/ftwdt010.h
> >> >>
> >> >> diff --git a/hw/arm/Makefile.objs b/hw/arm/Makefile.objs
> >> >> index 2190edd..bc8e2de 100644
> >> >> --- a/hw/arm/Makefile.objs
> >> >> +++ b/hw/arm/Makefile.objs
> >> >> @@ -41,3 +41,4 @@ obj-y += ftintc020.o
> >> >> obj-y += ftahbc020.o
> >> >> obj-y += ftddrii030.o
> >> >> obj-y += ftpwmtmr010.o
> >> >> +obj-y += ftwdt010.o
> >> >> diff --git a/hw/arm/faraday_a369_soc.c
> >> >> b/hw/arm/faraday_a369_soc.c
> >> >> index 66d9891..1bf64d4 100644
> >> >> --- a/hw/arm/faraday_a369_soc.c
> >> >> +++ b/hw/arm/faraday_a369_soc.c
> >> >> @@ -68,6 +68,25 @@ static void a369soc_reset(DeviceState *ds)
> >> >> }
> >> >>
> >> >> static void
> >> >> +a369soc_system_reset(void *opaque)
> >> >> +{
> >> >> + FaradaySoCState *s = FARADAY_SOC(opaque);
> >> >> +
> >> >> + if (s->scu) {
> >> >> + device_reset(s->scu);
> >> >> + }
> >> >> + if (s->ddrc) {
> >> >> + device_reset(s->ddrc);
> >> >> + }
> >> >> + if (s->ahbc) {
> >> >> + device_reset(s->ahbc);
> >> >> + }
> >> >> + if (s->cpu) {
> >> >> + cpu_reset(CPU(s->cpu));
> >> >> + }
> >> >> +}
> >> >
> >> > Why is this needed? Aren't they called already by
> >> >
> >> > qemu_register_reset(qbus_reset_all_fn,
> >> > sysbus_get_default());
> >> >
> >> > ?
> >> >
> >>
> >> It doesn't work while running under ROM mode. ( no -kernel )
> >> Because Faraday SoC Platform usually designed to boot from ROM and
> >> followed by an AHB remapping process (i.e. remap ROM/RAM address).
> >
> > What doesn't work exactly? Why aren't these called? Or are
> > you forcing a particular reset order?
> >
> > Paolo
>
> While booting from ROM, the faraday soc usually remap the ROM / RAM
> before jumping into linux.
>
> In other words, the system mapping is:
>
> 1. Power-On:
>
> ROM: 0x00000000
> RAM: N/A
> SRAM: 0xA0000000
>
> 2. AHB Remap (u-boot/linux)
>
> ROM: 0x20000000
> RAM: 0x00000000
>
> So I have to register my own reset handler to
>
> 1. Undo the ROM/RAM remap (i.e. device_reset(s->ahbc))
> 2. Reset CPU
I understand that. What I'm missing is, why these reset handlers aren't
called anyway when QEMU does qemu_devices_reset(), for example from
qemu_system_reset().
Also, I do not understand who performs this again:
+ /* Remap AHB slave 4 (ROM) & slave 6 (RAM) */
+ /* 1. Remap RAM to base of ROM */
+ s->ram_base = s->ahb_slave[4] & 0xfff00000;
+ s->ahb_slave[6] = s->ram_base | (s->ahb_slave[6] & 0x000f0000);
+ /* 2. Remap ROM to base of ROM + size of RAM */
+ s->rom_base = s->ram_base
+ + ((1 << extract32(s->ahb_slave[6], 16, 4)) << 20);
+ s->ahb_slave[4] = s->rom_base | (s->ahb_slave[4] & 0x000f0000);
when you do a system_reset and the board was started in kernel mode.
Paolo
- [Qemu-devel] [PATCH v6 01/24] target-arm: add Faraday ARMv5TE processors support, (continued)
- [Qemu-devel] [PATCH v6 01/24] target-arm: add Faraday ARMv5TE processors support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 02/24] hw/arm: add Faraday a369 SoC platform support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 03/24] hw/arm: add Faraday FTINTC020 interrupt controller support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 04/24] hw/arm: add Faraday FTAHBC020 support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 05/24] hw/arm: add Faraday FTDDRII030 support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 06/24] hw/arm: add Faraday FTPWMTMR010 timer support, Kuo-Jung Su, 2013/03/06
- [Qemu-devel] [PATCH v6 07/24] hw/arm: add Faraday FTWDT010 watchdog timer support, Kuo-Jung Su, 2013/03/06
[Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Kuo-Jung Su, 2013/03/06
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Paolo Bonzini, 2013/03/06
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Kuo-Jung Su, 2013/03/07
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Paolo Bonzini, 2013/03/07
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Wei-Ren Chen, 2013/03/07
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Paolo Bonzini, 2013/03/07
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Wei-Ren Chen, 2013/03/07
- Re: [Qemu-devel] [PATCH v6 08/24] hw/arm: add Faraday FTRTC011 RTC timer support, Kuo-Jung Su, 2013/03/07