[MPC7448] machdep_calls

Sébastien Chrétien sebastien.chretien.enseirb at gmail.com
Tue Aug 19 19:23:05 EST 2008


So I will write .setup_arch of machine_call  structure.
When is ppc_md.setup_arch() called ?

2008/8/19, Benjamin Herrenschmidt <benh at kernel.crashing.org>:
>
> On Tue, 2008-08-19 at 09:00 +0200, Sébastien Chrétien wrote:
> > I have no screen that's why I have to use UART. I followed the CPM
> > model in head_32.S :
> > #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
> > setup_cpm_bat:
> >     lis    r8, 0xf000
> >     ori    r8, r8,    0x002a
> >     mtspr    SPRN_DBAT1L, r8
> >
> >     lis    r11, 0xf000
> >     ori    r11, r11, (BL_1M << 2) | 2
> >     mtspr    SPRN_DBAT1U, r11
> >
> >     blr
> > #endif
>
>
> The "EARLY DEBUG" stuff is a pile of hacks to help with bringup,
> it's definitely not a long term solution to your problems.
>
> You may also want to look at Grant Likely's work on doing proper
> early ioremap using BATs.
>
>
> > With this code  I can use udbg.
> >
> > According to you, what is the best way ?
>
>
> The above is fine for early debug console. But that's definitely
> not the only kind of thing you may want to put in your setup_arch()...
> Look at what others do.
>
> Ben.
>
>
> > 2008/8/18, Benjamin Herrenschmidt <benh at kernel.crashing.org>:
> >         On Mon, 2008-08-18 at 16:17 +0200, Sébastien Chrétien wrote:
> >         > The mpc7448hpc2 uses a tsi108-bridge. My board uses an IP on
> >         a FPGA..
> >         > I read the code of mpc7448_hpc2.c.
> >         > It uses a ioremap in order to iniatilize the tsi108
> >         registers. But I
> >         > have already initialized MMU with my registers in HEAD_32.S.
> >         Do I need
> >         > to use ioremap in setup_arch() ?
> >
> >
> >         Why did you hack head_32.S ? You shouldn't do that... This is
> >         common
> >         code, not platform code.
> >
> >         Ben.
> >
> >         >
> >         >
> >         >
> >         > 2008/8/18, Michael Ellerman <michael at ellerman.id.au>:
> >         >         On Mon, 2008-08-18 at 13:35 +0200, Sébastien
> >         Chrétien wrote:
> >         >         > Can somebody explain me the aim of the
> >         >         function  "setup_arch" in the
> >         >         > machine_call structure ?
> >         >
> >         >
> >         >         Is this MPC7448 anything like an mpc7448hpc2 ?
> >         >
> >         >         If so maybe you should start by looking at the code
> >         for it in:
> >         >
> >         >         arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c
> >         >
> >         >         Even if it's not related, that will give you some
> >         idea of what
> >         >         the
> >         >         callbacks are for.
> >         >
> >         >         cheers
> >         >
> >         >         --
> >         >         Michael Ellerman
> >         >         OzLabs, IBM Australia Development Lab
> >         >
> >         >         wwweb: http://michael.ellerman.id.au
> >         >         phone: +61 2 6212 1183 (tie line 70 21183)
> >         >
> >         >         We do not inherit the earth from our ancestors,
> >         >         we borrow it from our children. - S.M.A.R.T Person
> >         >
> >         >
> >
> >
>
>
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