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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A1CFC001B0 for ; Wed, 19 Jul 2023 20:43:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229819AbjGSUnT (ORCPT ); Wed, 19 Jul 2023 16:43:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229480AbjGSUnS (ORCPT ); Wed, 19 Jul 2023 16:43:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CD1909E; Wed, 19 Jul 2023 13:43:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 699A46182F; Wed, 19 Jul 2023 20:43:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A388C433C8; Wed, 19 Jul 2023 20:43:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689799396; bh=Tyjuk2o5/6zWPoP1zMw3/ypWfYVhxYWg4rjX3S4aZtg=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=FiAa9y/2tv71wEXdSyAGzNYhBUxM+hvhiaqxmMnzXpP8UcpFHg9j/QVPzqJ1auM37 lbHnkX0NYfz7AI9yHQjtRu9TYLXdBTGLfLBfe6m5AW1ZMZ1Db0D8YHv0o/kXURCPBg 6o2jg6IJRGYIgt179i38xPkXzaLIsMgsxFnK0fpi91ooT8kKWcS8B/1ovFntmhRFU0 Q8BPuImDwnSqp/UoGGhqBPPlkEWcYQ8KgeRMf3mdhJTJhj6Do9nbOMZCXofTjkWIFw Snq6WsZ6LAoKSxoq4zjBx4b7UYqEw6ID5xRozHH9G3pl2v8PjgHJhBEsxoAdXceHil xp9Aiqzk429pA== Date: Wed, 19 Jul 2023 15:43:14 -0500 From: Bjorn Helgaas To: Sui Jingfeng Cc: David Airlie , linux-fbdev@vger.kernel.org, Sui Jingfeng , kvm@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-pci@vger.kernel.org Subject: Re: [Intel-gfx] [PATCH v3 3/9] PCI/VGA: Switch to aperture_contain_firmware_fb_nonreloc() Message-ID: <20230719204314.GA512532@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230711164310.791756-4-sui.jingfeng@linux.dev> Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org [+cc linux-pci; I don't apply or ack PCI patches unless they appear there] On Wed, Jul 12, 2023 at 12:43:04AM +0800, Sui Jingfeng wrote: > From: Sui Jingfeng > > The observation behind this is that we should avoid accessing the global > screen_info directly. Call the aperture_contain_firmware_fb_nonreloc() > function to implement the detection of whether an aperture contains the > firmware FB. Because it's better to access the global screen_info from aperture_contain_firmware_fb_nonreloc()? The reasoning here is not super clear to me. > This patch helps to decouple the determination from the implementation. > Or, in other words, we intend to make the determination opaque to the > caller. The determination may choose to be arch-dependent or > arch-independent. But vgaarb, as a consumer of the determination, > shouldn't care how the does determination is implemented. "how the determination ..." (drop the "does") Are you saying that aperture_contain_firmware_fb_nonreloc() might be arch-dependent? Are there multiple callers? Or does this just move code from one place to a more appropriate place? > Signed-off-by: Sui Jingfeng > --- > drivers/pci/vgaarb.c | 19 ++++--------------- > 1 file changed, 4 insertions(+), 15 deletions(-) > > diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c > index bf96e085751d..953daf731b2c 100644 > --- a/drivers/pci/vgaarb.c > +++ b/drivers/pci/vgaarb.c > @@ -14,6 +14,7 @@ > #define vgaarb_info(dev, fmt, arg...) dev_info(dev, "vgaarb: " fmt, ##arg) > #define vgaarb_err(dev, fmt, arg...) dev_err(dev, "vgaarb: " fmt, ##arg) > > +#include > #include > #include > #include > @@ -26,7 +27,6 @@ > #include > #include > #include > -#include > #include > #include > #include > @@ -558,20 +558,11 @@ void vga_put(struct pci_dev *pdev, unsigned int rsrc) > } > EXPORT_SYMBOL(vga_put); > > +/* Select the device owning the boot framebuffer if there is one */ > static bool vga_is_firmware_default(struct pci_dev *pdev) > { > #if defined(CONFIG_X86) || defined(CONFIG_IA64) > - u64 base = screen_info.lfb_base; > - u64 size = screen_info.lfb_size; > struct resource *r; > - u64 limit; > - > - /* Select the device owning the boot framebuffer if there is one */ > - > - if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) > - base |= (u64)screen_info.ext_lfb_base << 32; > - > - limit = base + size; > > /* Does firmware framebuffer belong to us? */ > pci_dev_for_each_resource(pdev, r) { > @@ -581,10 +572,8 @@ static bool vga_is_firmware_default(struct pci_dev *pdev) > if (!r->start || !r->end) > continue; > > - if (base < r->start || limit >= r->end) > - continue; > - > - return true; > + if (aperture_contain_firmware_fb_nonreloc(r->start, r->end)) > + return true; > } > #endif > return false; > -- > 2.25.1 >