From: "Kevin D. Kissell" <kevink@mips.com>
To: "Suresh. R" <suresh@mistralsoftware.com>, <linux-mips@linux-mips.org>
Subject: Re: VR4131 - MQ1132 - UPD63335
Date: Fri, 16 Jan 2004 11:09:09 +0100 [thread overview]
Message-ID: <014a01c3dc18$c92b74a0$10eca8c0@grendel> (raw)
In-Reply-To: 40079391.7080301@mistralsoftware.com
If I recall correctly, WinCE runs drivers and system services in User mode,
so any memory-mapped I/O would need to be set-up explicitly in the virtual
address space. As Geert has pointed out, so long as it's in that first 512MB,
a Linux driver running in Kernel mode can access it directly via Kseg1 (or
Kseg0, if you wanted to be able to cache the data).
----- Original Message -----
From: "Suresh. R" <suresh@mistralsoftware.com>
To: <linux-mips@linux-mips.org>
Sent: Friday, January 16, 2004 8:32
Subject: VR4131 - MQ1132 - UPD63335
> Hi,
> This might be a very basic question, but I am very new to this field.
> So please help me.
>
> I am writing a linux device driver for UPD63335 audio codec. Its
> controlled through the MQ1132 co-processor. The VR4131 is the processor.
> The memory of MQ1132 is mapped to the processor memory in Kseg1 (0xA000
> 0000 onwards) which the manual says is TLB Unmapped region. Now my
> question is is it necessary to map this region before using it in Linux.
> Actually I have WinCE code for my reference. In that code the programmer
> is mapping the region using Virtual Cpoy and Virtual Alloc. Is it
> necessary to do that or Can I directly address the memory locatoin.
>
> Please help
>
> Thanks in advance
>
> Regards
> Suresh
>
>
>
WARNING: multiple messages have this Message-ID (diff)
From: "Kevin D. Kissell" <kevink@mips.com>
To: "Suresh. R" <suresh@mistralsoftware.com>, linux-mips@linux-mips.org
Subject: Re: VR4131 - MQ1132 - UPD63335
Date: Fri, 16 Jan 2004 11:09:09 +0100 [thread overview]
Message-ID: <014a01c3dc18$c92b74a0$10eca8c0@grendel> (raw)
Message-ID: <20040116100909.nuXVF_h1Oex4ZZsmAfWDi-k-uxRfPs1FDO1TyCN3aUQ@z> (raw)
In-Reply-To: 40079391.7080301@mistralsoftware.com
If I recall correctly, WinCE runs drivers and system services in User mode,
so any memory-mapped I/O would need to be set-up explicitly in the virtual
address space. As Geert has pointed out, so long as it's in that first 512MB,
a Linux driver running in Kernel mode can access it directly via Kseg1 (or
Kseg0, if you wanted to be able to cache the data).
----- Original Message -----
From: "Suresh. R" <suresh@mistralsoftware.com>
To: <linux-mips@linux-mips.org>
Sent: Friday, January 16, 2004 8:32
Subject: VR4131 - MQ1132 - UPD63335
> Hi,
> This might be a very basic question, but I am very new to this field.
> So please help me.
>
> I am writing a linux device driver for UPD63335 audio codec. Its
> controlled through the MQ1132 co-processor. The VR4131 is the processor.
> The memory of MQ1132 is mapped to the processor memory in Kseg1 (0xA000
> 0000 onwards) which the manual says is TLB Unmapped region. Now my
> question is is it necessary to map this region before using it in Linux.
> Actually I have WinCE code for my reference. In that code the programmer
> is mapping the region using Virtual Cpoy and Virtual Alloc. Is it
> necessary to do that or Can I directly address the memory locatoin.
>
> Please help
>
> Thanks in advance
>
> Regards
> Suresh
>
>
>
next prev parent reply other threads:[~2004-01-16 10:08 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-01-16 7:32 VR4131 - MQ1132 - UPD63335 Suresh. R
2004-01-16 9:49 ` Geert Uytterhoeven
2004-01-16 9:49 ` Geert Uytterhoeven
2004-01-16 10:09 ` Kevin D. Kissell [this message]
2004-01-16 10:09 ` Kevin D. Kissell
2004-01-17 12:20 ` Ralf Baechle
2004-01-17 12:51 ` Jan-Benedict Glaw
2004-01-18 9:23 ` Dimitri Torfs
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