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Date: Wed, 13 May 2015 10:32:36 +0200
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Subject: Re: [Qemu-devel] when does a target frontend need to use
 gen_io_start()/gen_io_end() ?
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To: Pavel Dovgaluk <Pavel.Dovgaluk@ispras.ru>, 'Peter Maydell' <peter.maydell@linaro.org>, 'QEMU Developers' <qemu-devel@nongnu.org>
Cc: 'Richard Henderson' <rth@twiddle.net>



On 13/05/2015 08:57, Pavel Dovgaluk wrote:
>> > It's any instruction that can cause an icount read, typically through
>> > QEMU_CLOCK_VIRTUAL or cpu_get_ticks().
> Doesn't this mean that ARM has incorrect implementation of icount?
> MMIO is common for this platform, but none of memory accesses are
> surrounded with gen_io_start()/gen_io_end().

See here:

    if (mr != &io_mem_rom && mr != &io_mem_notdirty && !cpu_can_do_io(cpu)) {
        cpu_io_recompile(cpu, retaddr);
    }

in softmmu_template.h.

Paolo