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Date:   Mon, 9 May 2011 15:28:28 +0100
From:   Ralf Baechle <ralf@linux-mips.org>
To:     David Daney <ddaney@caviumnetworks.com>,
        linux-mips <linux-mips@linux-mips.org>, GCC <gcc@gcc.gnu.org>,
        binutils <binutils@sourceware.org>,
        Prasun Kapoor <prasun.kapoor@caviumnetworks.com>,
        rdsandiford@googlemail.com
Subject: Re: RFC: A new MIPS64 ABI
Message-ID: <20110509142828.GA7196@linux-mips.org>
References: <4D5990A4.2050308__41923.1521235362$1297715435$gmane$org@caviumnetworks.com>
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On Mon, Feb 21, 2011 at 07:45:41PM +0000, Richard Sandiford wrote:

> David Daney <ddaney@caviumnetworks.com> writes:
> > Background:
> >
> > Current MIPS 32-bit ABIs (both o32 and n32) are restricted to 2GB of
> > user virtual memory space.  This is due the way MIPS32 memory space is
> > segmented.  Only the range from 0..2^31-1 is available.  Pointer
> > values are always sign extended.
> >
> > Because there are not already enough MIPS ABIs, I present the ...
> >
> > Proposal: A new ABI to support 4GB of address space with 32-bit
> > pointers.
> 
> FWIW, I'd be happy to see this go into GCC.

So am I for the kernel primarily because it's not really a new ABI but
an enhancement of the existing N32 ABI.

  Ralf