[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-ppc] [Qemu-devel] [PATCH 06/10] r2d: Flash memory creation is
From: |
Markus Armbruster |
Subject: |
Re: [Qemu-ppc] [Qemu-devel] [PATCH 06/10] r2d: Flash memory creation is confused about size, mark FIXME |
Date: |
Tue, 19 Feb 2019 18:53:35 +0100 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) |
Peter Maydell <address@hidden> writes:
> On Tue, 19 Feb 2019 at 16:07, Philippe Mathieu-Daudé <address@hidden> wrote:
>>
>> On 2/18/19 1:56 PM, Markus Armbruster wrote:
>> Good news: when you read (0x0000, 0x0000, 0x0000, 0x0000) pflash IDs,
>> that means the code uses the "Virt PFlash".
Which code?
>> IOW this is not a physical
>> model, since the guest obviously doesn't care about checking the flash
>> model.
>> The "VirtPFlash" only has 64KiB sectors.
>>
>> I suggest we add a pflash_cfi02_create_virt(reduced args) helper to make
>> this obvious:
>>
>> pflash_cfi02_create_virt(paddr, name, size_bytes, mapping?).
>
> What would this be, and when would you use it without a
> /* FIXME this is not what the real hardware does */ ?
For a purely virtual machine such as ARM virt, perhaps?
Funnily, we use IDs 0x89, 0x18, 0x00, 0x00 there. Which first appeared
in the microblaze petalogix-s3adsp1800 machine (commit 2548de3a343, Jan
2010), then got copied to ppc virtex-ml507 (commit 2c50e26efdb, Sep
2010), microblaze petalogix-ml605 (commit 00914b7d970, Mar 2011), ppc
sam460ex (commit 4b387f9ee16, Feb 2018), arm vexpress-* in different
form (commit b8433303fbc and 0163a2dc80, Dec 2013), and finally arm virt
(commit acf82361c61, Sep 2014). Which ones match physical hardware is
anybody's guess.
> The real problem with most of these pflash creation calls
> is that they're using bogus data for the flash device
> (wrong IDs, wrong width, using the legacy weird implementation,
> etc etc)
Even better news: when we replace the helper function by longhand,
many of the (bogus) qdev_prop_set_FOO() become no-ops (because the
default is identically bogus), so we can sweep more of this under the
carpet!
> because nobody cares much about the boards or has
> real hardware to see what the hardware really is doing.
Remind me, why are we shipping stuff nobody cares much about?
[Qemu-ppc] [PATCH 07/10] mips_malta: Clean up definition of flash memory size somewhat, Markus Armbruster, 2019/02/18
Re: [Qemu-ppc] [PATCH 07/10] mips_malta: Clean up definition of flash memory size somewhat, Alex Bennée, 2019/02/21
[Qemu-ppc] [PATCH 04/10] sam460ex: Don't size flash memory to match backing image, Markus Armbruster, 2019/02/18