[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl
From: |
Alexander Graf |
Subject: |
Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op |
Date: |
Fri, 1 Jul 2011 00:28:19 +0200 |
On 01.07.2011, at 00:23, Scott Wood wrote:
> On Fri, 1 Jul 2011 00:18:22 +0200
> Alexander Graf <address@hidden> wrote:
>
>>
>> On 01.07.2011, at 00:11, Scott Wood wrote:
>>
>>> Almost, but what if we have write permission but not read?
>>
>> How would you write back data from a cache line when you haven't read it
>> earlier?
>
> The CPU can read it. The program can't.
Hrm. We can always just call the check manually and trigger the respective
interrupt :).
>>> but what about a race with DMA from the I/O thread?
>>
>> That'd simply be broken, but I don't quite see how it wouldn't with real
>> hardware either :).
>
> Real hardware doesn't generate a load/store sequence that the program didn't
> ask for -- where's the breakage?
Real hardware flushes whatever contents are in that cache line to RAM, no? So
it would collide with the DMA just as much. Or am I missing something?
Alex
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, (continued)
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Fabien Chouteau, 2011/06/28
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/28
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Fabien Chouteau, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Alexander Graf, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Alexander Graf, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Alexander Graf, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op,
Alexander Graf <=
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Scott Wood, 2011/06/30
- Re: [Qemu-devel] [PATCH] Add e500 instructions dcblc, dcbtls and dcbtstl as no-op, Alexander Graf, 2011/06/30