From patchwork Wed Oct 4 08:37:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mark Cave-Ayland X-Patchwork-Id: 1843086 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (4096-bit key; unprotected) header.d=ilande.co.uk header.i=@ilande.co.uk header.a=rsa-sha256 header.s=20220518 header.b=1ZEPtgj+; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4S0p6q07g5z1yng for ; Wed, 4 Oct 2023 19:40:35 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qnxOx-0003rU-JZ; Wed, 04 Oct 2023 04:38:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qnxOw-0003oy-Gq for qemu-devel@nongnu.org; Wed, 04 Oct 2023 04:38:38 -0400 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qnxOu-0007Vx-W1 for qemu-devel@nongnu.org; Wed, 04 Oct 2023 04:38:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=ilande.co.uk; s=20220518; h=Subject:Content-Transfer-Encoding:Content-Type: MIME-Version:References:In-Reply-To:Message-Id:Date:To:From:Sender:Reply-To: Cc:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=Jy6K0cKwB1zQ7ttHjHuJHcM4wAstBU3zagIKsjH/jMQ=; b=1ZEPtgj+T6s3a9+dS104TfA2Fe EASp9UFiHK6rrUdLGznwR9wJvufYIDcPvvHjTjC1xrSRl3KbUn3TFblKLxzfLAofx0zVLzNRRMsqC stC4dgWxbYwrtCuIdNFsfBTZF5m/kEXsFuHYZUx3NSMQ03PaJZ8c9j/L11YjbZt2sqinTC+vNdcS3 U7MBVo/NkI33btamqYowMx6g0aZLqnWPvDkeCiukAW/C9qbpMq29k+3DznnLeWhK54rYCVYihbo3v EMl+m9+2g89G56yY1QBciDKYSfAyRM1xreNMXQY6tPi9JqG/XQGJURBTZDBxahxQIFl+Lud10EaUA NEsvmaLKsWqUPquEUh74FGCJ2oJkTgKGvg4rcusFi7+v8pNJCwXCshoXVholAEUhjyar8y42FxAnL q4w+ZxPr6RsFDGlI8R/rkoEiSwPG9mooEGaSN2KzT6EdJGRlQBVcwGRKrHr0C/suJ8Ygvas2NIHUC YAJuTxqNPQv2W2vGWjbH6QBgI/3yn9GL41DEwljz/utmPUs424dH4GyG8hxn3TyeRIsumPzkYAzSy +rJejIQ9juA2IAO5RhSBhRLf6vXkctL4bg6I6Lew7vDUYTsDwypnxz8P0QF29sLteAhNjPUaMOcDr G1LZ8koefJ0VXROlRx8HdlwIPf52q8EI4jXdJQMrY=; Received: from host86-159-123-68.range86-159.btcentralplus.com ([86.159.123.68] helo=localhost.localdomain) by mail.ilande.co.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qnxOg-0006za-NB; Wed, 04 Oct 2023 09:38:26 +0100 From: Mark Cave-Ayland To: laurent@vivier.eu, qemu-devel@nongnu.org Date: Wed, 4 Oct 2023 09:37:52 +0100 Message-Id: <20231004083806.757242-7-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231004083806.757242-1-mark.cave-ayland@ilande.co.uk> References: <20231004083806.757242-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 86.159.123.68 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH v4 06/20] q800: allow accesses to RAM area even if less memory is available X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.ilande.co.uk) Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.ilande.co.uk X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org MacOS attempts a series of writes and reads over the entire RAM area in order to determine the amount of RAM within the machine. Allow accesses to the entire RAM area ignoring writes and always reading zero for areas where there is no physical RAM installed to allow MacOS to detect the memory size without faulting. Signed-off-by: Mark Cave-Ayland Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Laurent Vivier --- hw/m68k/q800.c | 30 +++++++++++++++++++++++++++++- include/hw/m68k/q800.h | 1 + 2 files changed, 30 insertions(+), 1 deletion(-) diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c index 081b95e9cf..3209309173 100644 --- a/hw/m68k/q800.c +++ b/hw/m68k/q800.c @@ -86,6 +86,9 @@ #define MAC_CLOCK 3686418 +/* Size of whole RAM area */ +#define RAM_SIZE 0x40000000 + /* * Slot 0x9 is reserved for use by the in-built framebuffer whilst only * slots 0xc, 0xd and 0xe physically exist on the Quadra 800 @@ -218,6 +221,27 @@ static const MemoryRegionOps machine_id_ops = { }, }; +static uint64_t ramio_read(void *opaque, hwaddr addr, unsigned size) +{ + return 0x0; +} + +static void ramio_write(void *opaque, hwaddr addr, uint64_t val, + unsigned size) +{ + return; +} + +static const MemoryRegionOps ramio_ops = { + .read = ramio_read, + .write = ramio_write, + .endianness = DEVICE_BIG_ENDIAN, + .valid = { + .min_access_size = 1, + .max_access_size = 4, + }, +}; + static void q800_machine_init(MachineState *machine) { Q800MachineState *m = Q800_MACHINE(machine); @@ -262,7 +286,11 @@ static void q800_machine_init(MachineState *machine) qemu_register_reset(main_cpu_reset, &m->cpu); /* RAM */ - memory_region_add_subregion(get_system_memory(), 0, machine->ram); + memory_region_init_io(&m->ramio, OBJECT(machine), &ramio_ops, &m->ramio, + "ram", RAM_SIZE); + memory_region_add_subregion(get_system_memory(), 0x0, &m->ramio); + + memory_region_add_subregion(&m->ramio, 0, machine->ram); /* * Create container for all IO devices diff --git a/include/hw/m68k/q800.h b/include/hw/m68k/q800.h index 98097165d9..04e4e0bce3 100644 --- a/include/hw/m68k/q800.h +++ b/include/hw/m68k/q800.h @@ -60,6 +60,7 @@ struct Q800MachineState { MacfbNubusState macfb; DJMEMCState djmemc; IOSBState iosb; + MemoryRegion ramio; MemoryRegion macio; MemoryRegion macio_alias; MemoryRegion machine_id;