From patchwork Sun Jul 2 15:48:23 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: 1802394 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org 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=) 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=Q5TP8wUL; dkim-atps=neutral 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 4QvD5h0Bc1z20ZF for ; Mon, 3 Jul 2023 01:50:00 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qFzK7-0004PZ-Hh; Sun, 02 Jul 2023 11:49:15 -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 1qFzK6-0004PA-AE for qemu-devel@nongnu.org; Sun, 02 Jul 2023 11:49:14 -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 1qFzK4-0007R1-Dz for qemu-devel@nongnu.org; Sun, 02 Jul 2023 11:49:14 -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:MIME-Version: References:In-Reply-To:Message-Id:Date:To:From:Sender:Reply-To:Cc: Content-Type: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=NbYwBJKPZsJu1nxMNVD6PhDa955mRSYxjAw5kFMc3x8=; b=Q5TP8wULNMe1NR/Zsq3wTAUm7e Vo0VYnsWT/K6d4Z2aBdxEylyox5zQe5S5e7NOKptUv4ArT8yILT/fyCrVivAJ3vBpszBI25qWAa/N XBu4xfuCaQQnUbegBtgFrbuRsxJXbmhih3XNtFURRpezdlrqEKljqNpTva4OhZjEPgGOJvOz3c3Hi EgkEPBYXONVLKYMwi1DL6buH6K10I9kS9KoBbPDNnOtLKxAQ7IVhS1dQjzJmlLsHSHRuFTpqxrkJC r2R7FOpf6jhKyBPzTAeuwby0QIdPCchC6apjSodapnRtf/1mEsoN/OWxrkOTnqMWmgoXYCjdatEzP UOBq0b3mgczxr7YXiiu0yKTugaB+d97hGKS9tYtt1LOE/tYYQnIyYTMBlB2r60xobllapPrzajBWF HhxWzysNhAZgoCtxK+F/ZYV/rfP5ml7t92zeXAflawJNNUPaHEXVfQavuFMPIBD2Tx/vHazgujlTe oxHBZCHhufS9leXmnvK+GFmddAmD7GNWsQvY4FA+fIxMsy+q8mOV3/qED7NPZIVvdY92kbWRmQMnT bCQSbpPcz2ChKdB1hpCyOs+9ns3QYm6jqFB2lobryZoVXq0zA3WxGznYR8CucK+O8bBcT1f/3PAXU ScWeQ00l2jL4q5rIeDk+UWOdnSCvrq2OcRFkurb6U=; Received: from [2a00:23c4:8bad:df00:f732:dd76:7417:d15b] (helo=kentang.home) by mail.ilande.co.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qFzJo-0001Ji-T4; Sun, 02 Jul 2023 16:49:00 +0100 From: Mark Cave-Ayland To: laurent@vivier.eu, qemu-devel@nongnu.org Date: Sun, 2 Jul 2023 16:48:23 +0100 Message-Id: <20230702154838.722809-7-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230702154838.722809-1-mark.cave-ayland@ilande.co.uk> References: <20230702154838.722809-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a00:23c4:8bad:df00:f732:dd76:7417:d15b X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH 06/21] 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, T_SCC_BODY_TEXT_LINE=-0.01 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;