From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44618) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bKYsZ-0008CJ-Qs for qemu-devel@nongnu.org; Tue, 05 Jul 2016 18:31:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bKYsX-0001se-Po for qemu-devel@nongnu.org; Tue, 05 Jul 2016 18:31:42 -0400 Received: from mail-vk0-x232.google.com ([2607:f8b0:400c:c05::232]:35172) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bKYsX-0001rI-4w for qemu-devel@nongnu.org; Tue, 05 Jul 2016 18:31:41 -0400 Received: by mail-vk0-x232.google.com with SMTP id v6so13532020vkb.2 for ; Tue, 05 Jul 2016 15:31:39 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <1465209480-71364-1-git-send-email-rolnik@amazon.com> <1465209480-71364-4-git-send-email-rolnik@amazon.com> From: Peter Maydell Date: Tue, 5 Jul 2016 23:31:17 +0100 Message-ID: Content-Type: text/plain; charset=UTF-8 Subject: Re: [Qemu-devel] [PATCH v4 3/9] target-avr: adding a sample AVR board List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Rolnik Cc: QEMU Developers , Michael Rolnik , Richard Henderson On 5 July 2016 at 23:22, Michael Rolnik wrote: > Peter, > > I do not understand this comment > > Exactly one of these memory regions (your main "RAM") should be > allocated via memory_region_allocate_system_memory() > [which does the vmstate_register_ram_global() for that MR]. > The idea is that every board has one-and-only-one main RAM MR. > (We should have a memory_region_allocate_aux_memory() > as the parallel API to save you having to do the vmstate_register_ram_global > yourself for the other two, but currently we don't.) > > could you please point me to an example/documentation. See for instance hw/arm/vexpress.c. We call memory_region_allocate_system_memory() only once, for the main RAM. The little bit of RAM "vexpress.a15sram" is not allocated with that function. > as for this one > > This isn't very descriptive; a short phrase which gives users > a clue about whether they want to use this board would be good. > > currently I am concerned with CPU and not with boards/devices/models. > I hope, once there is AVR CPU, some people (including me) will join and > create real boards, this one is just a sample. it does not do any real > stuff. it allows to load a simple program and run. > If I start to design a real board/model now it will take me some time and > during this time no one is going to use/profit from AVR CPU in QEMU. > that's why it's called sample. Unfortunately it's not quite that simple. Once code goes into QEMU, we have to maintain it, and we need to continue to support users who have started using it. That means that we could easily still have this "sample" board around in five years time. So you need to get it at least basically right and useful from the beginning. My point about the better descriptive phrase is that this is user-facing documentation (it appears in "-M help" output where we list all the supported boards). "sample" on its own doesn't do much to help users or suggest to them or remind them what this board model is. thanks -- PMM