From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 32B92D15D86 for ; Wed, 3 Dec 2025 15:27:42 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vQokc-0006BP-1M; Wed, 03 Dec 2025 10:26:42 -0500 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 1vQoka-0006AO-3h; Wed, 03 Dec 2025 10:26:40 -0500 Received: from mgamail.intel.com ([192.198.163.16]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vQokY-00023c-8i; Wed, 03 Dec 2025 10:26:39 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1764775598; x=1796311598; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=Jrc8P4puiHEWVgK5gKHDVPB4edrZpUnxl7rtp5oYUy8=; b=jVD9kHJvCjmfU9K5/McOEiScXP3biRSs7him7K55UeLf4QWb1noF8IYi ZcHdXyiaNl0MfusyPqqsDyMY7zex+z25upGZooOkDlEq6y/F8OPjcZsGH UrElGzV48HTbMj7r0alVoUMIQs6l14iinxF15+YSklmy0GDjjMrbtuMSa rVmZtJtq5itlsEVJVtJ8u0MoYeEmv1vFkau4ogeU7Qq1uK3JsoYEk/q2h Bj8LmkzP8fqc0Zk1CtjYJHZFMLHU2rs8u0cZLVXJ9wWtK9zvbCeeiHCiz smsFSpUtbkmw66K09DnQSTOwqTkYnucFaolKCfkn8pAQwWjQTeh0nNsy+ w==; X-CSE-ConnectionGUID: W3Cy0NTSTgqSUVLV+HoGpA== X-CSE-MsgGUID: LLQ4j/H7SseyavfcdlAXgw== X-IronPort-AV: E=McAfee;i="6800,10657,11631"; a="54323027" X-IronPort-AV: E=Sophos;i="6.20,246,1758610800"; d="scan'208";a="54323027" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa110.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Dec 2025 07:26:34 -0800 X-CSE-ConnectionGUID: M+KB5REsSvuzF70W5+fI9g== X-CSE-MsgGUID: N2mvK8ajRTiHQAJDmkCSxw== X-ExtLoop1: 1 Received: from liuzhao-optiplex-7080.sh.intel.com (HELO localhost) ([10.239.160.39]) by fmviesa003.fm.intel.com with ESMTP; 03 Dec 2025 07:26:32 -0800 Date: Wed, 3 Dec 2025 23:51:14 +0800 From: Zhao Liu To: Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Cc: qemu-devel@nongnu.org, qemu-ppc@nongnu.org, Igor Mammedov , Xiaoyao Li , Mark Cave-Ayland , qemu-riscv@nongnu.org, qemu-arm@nongnu.org, Artyom Tarasenko Subject: Re: [PATCH-for-11.0 v6 08/13] hw/sparc64/sun4u: Use fw_cfg_init_io_nodma() Message-ID: References: <20251203060942.57851-1-philmd@linaro.org> <20251203060942.57851-9-philmd@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251203060942.57851-9-philmd@linaro.org> Received-SPF: pass client-ip=192.198.163.16; envelope-from=zhao1.liu@intel.com; helo=mgamail.intel.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi Philippe, > diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c > index 82c3e7c855b..6dc9f64b74d 100644 > --- a/hw/sparc64/sun4u.c > +++ b/hw/sparc64/sun4u.c > @@ -683,14 +683,7 @@ static void sun4uv_init(MemoryRegion *address_space_mem, > graphic_width, graphic_height, graphic_depth, > (uint8_t *)&macaddr); > > - dev = qdev_new(TYPE_FW_CFG_IO); > - qdev_prop_set_bit(dev, "dma_enabled", false); > - object_property_add_child(OBJECT(ebus), TYPE_FW_CFG, OBJECT(dev)); There's another difference: fw_cfg_init_io_nodma() uses `machine` as the parent and here sun4uv uses `ebus`. I think maybe one reason to use `ebus` is because... > - sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal); > - memory_region_add_subregion(pci_address_space_io(ebus), BIOS_CFG_IOPORT, ^^^^^^^^^^^^^^^^^^^^^^^^^^ ... because the parent region is managed by ebus. Perhaps we should add another argument: Object *parent? > - &FW_CFG_IO(dev)->comb_iomem); > - Thanks, Zhao