From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Ni83G-000060-J3 for qemu-devel@nongnu.org; Thu, 18 Feb 2010 10:12:26 -0500 Received: from [199.232.76.173] (port=58640 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Ni83F-00005O-S6 for qemu-devel@nongnu.org; Thu, 18 Feb 2010 10:12:25 -0500 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1Ni83E-0005Hl-ME for qemu-devel@nongnu.org; Thu, 18 Feb 2010 10:12:25 -0500 Received: from mail-bw0-f218.google.com ([209.85.218.218]:60079) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Ni83E-0005HF-Ca for qemu-devel@nongnu.org; Thu, 18 Feb 2010 10:12:24 -0500 Received: by bwz10 with SMTP id 10so245600bwz.2 for ; Thu, 18 Feb 2010 07:12:22 -0800 (PST) Message-ID: <4B7D51A2.8080704@mvista.com> Date: Thu, 18 Feb 2010 17:41:38 +0300 From: Dmitry Antipov MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] How to get 64-bit MMIO? List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hello all, is there any support for 64-bit MMIO? I'm trying to emulate 16750-like UART by adopting current 16550A emulation. The problem is that my (MIPS) hardware is 64-bit, and native software issues 64-bit load/stores (LD/SD) to talk with all hardware registers, which are all 64-bit too (for UART case, only 8 lower bits are used, BTW). As I can see, qemu splits 64-bit access into two 32-bit back-to-back ones, but this gives catastrophic results if host and guest has different byte order - i.e. write 0x0000000000000001 to 0x100 gives write 0x00000000 to 0x100 and 0x10000000 to 0x104 because 64-bit quantities are swapped within 32-bit halves. Dmitry