From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH] KVM/arm: kernel low level debug support for ARM32 virtual platforms Date: Tue, 3 Nov 2015 17:33:44 +0000 Message-ID: <20151103173344.GC8644@n2100.arm.linux.org.uk> References: <1446508313-24404-1-git-send-email-m.smarduch@samsung.com> <5638E1CD.8090006@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 83E3C49794 for ; Tue, 3 Nov 2015 12:30:50 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id c5bVyljsKDTB for ; Tue, 3 Nov 2015 12:30:49 -0500 (EST) Received: from pandora.arm.linux.org.uk (pandora.arm.linux.org.uk [78.32.30.218]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id CBFD349776 for ; Tue, 3 Nov 2015 12:30:48 -0500 (EST) Content-Disposition: inline In-Reply-To: <5638E1CD.8090006@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Christopher Covington Cc: kvm@vger.kernel.org, marc.zyngier@arm.com, andre.przywara@arm.com, will.deacon@arm.com, grant.likely@secretlab.ca, robherring2@gmail.com, catalin.marinas@arm.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org List-Id: kvmarm@lists.cs.columbia.edu On Tue, Nov 03, 2015 at 11:33:17AM -0500, Christopher Covington wrote: > > diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug > > index a2e16f9..d126bd4 100644 > > --- a/arch/arm/Kconfig.debug > > +++ b/arch/arm/Kconfig.debug > > @@ -1155,6 +1155,28 @@ choice > > This option selects UART0 on VIA/Wondermedia System-on-a-chip > > devices, including VT8500, WM8505, WM8650 and WM8850. > > > > + config DEBUG_VIRT_UART_QEMU > > + bool "Kernel low-level debugging on QEMU Virtual Platform" > > + depends on ARCH_VIRT > > + select DEBUG_UART_PL01X > > + help > > + Say Y here if you want the debug print routines to direct > > + their output to PL011 UART port on QEMU Virtual Platform. > > + Appropriate address values are: > > + PHYS VIRT > > + 0x9000000 0xf8090000 > > I thought the only guarantee the virt machine had about the memory map was > that it would be described in the device tree. This LL debug stuff is used prior to device tree being parsed. -- FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.