qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH v3 1/1] nios2: Add Altera JTAG UART emulation


From: Marek Vasut
Subject: Re: [Qemu-devel] [PATCH v3 1/1] nios2: Add Altera JTAG UART emulation
Date: Thu, 9 Feb 2017 18:25:16 +0100
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.4.0

On 02/09/2017 05:34 PM, Bystricky, Juro wrote:
>> The code running on nios2 can issue unaligned access to the jtag uart
>> registers, yes ? If that happens, what happens on real HW and how is
>> this emulated ?
> 
> Misaligned accesses to any registers would raise an exception.
> The exception is handled by interrupt controller, either "real"
> or emulated. Such access should never reach code for jtag uart.
> 
> Also note we only allow access size 4 in the code:
> 
> static const MemoryRegionOps juart_ops = {
>     .read = altera_juart_read,
>     .write = altera_juart_write,
>     .endianness = DEVICE_LITTLE_ENDIAN,
>     .valid = {
>         .min_access_size = 4,
>         .max_access_size = 4
>     }
> };

This answers my question , thanks.

-- 
Best regards,
Marek Vasut



reply via email to

[Prev in Thread] Current Thread [Next in Thread]