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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0C85C433E0 for ; Thu, 18 Feb 2021 12:20:08 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 98F1F64DA1 for ; Thu, 18 Feb 2021 12:20:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98F1F64DA1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:References: To:From:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=FXUrF1IGH1ioS+hpqIQQAWFJQiYHFRgf+Kob/wRnLI8=; b=ThN0O3zEW7oG/SotjXzsXoALp MivPJRAHDiaWjiGqXtiMTQh9LiToF++++hwlzVMksBVvaha2R2DtorNcC7Zw+7MNXJKAKy0qloSE6 3Vo0NulTtE/1No2jXULu+gTY7wJXp/kvs7e8UbDHM8tSfkxA8KX9lOzSATORcusk+LSbfagrg3ryg gW2gvKIsjZrKXLIDScCfmNvj/JmG2dQMihlpx2q3Omqb7GPdTfoBnoZB9dC0CJT33xPUkOAPV2Ozb wdQWbqOIJTIyRzsFMWK3WndEa0Nn8jij2WWUruKYSxoeRWkYRmmJDELfnLU18a1/1goLEEceF0FEK v90xNBc3w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lCiGP-0004Js-Ds; Thu, 18 Feb 2021 12:18:33 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lCiGM-0004JP-Bc for linux-arm-kernel@lists.infradead.org; Thu, 18 Feb 2021 12:18:31 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 985861FB; Thu, 18 Feb 2021 04:18:23 -0800 (PST) Received: from [192.168.0.110] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9B7123F73D; Thu, 18 Feb 2021 04:18:22 -0800 (PST) Subject: Re: [PATCH kvmtool 20/21] hw/serial: ARM/arm64: Use MMIO at higher addresses From: Alexandru Elisei To: Andre Przywara , Will Deacon , Julien Thierry References: <20201210142908.169597-1-andre.przywara@arm.com> <20201210142908.169597-21-andre.przywara@arm.com> Message-ID: Date: Thu, 18 Feb 2021 12:18:38 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210218_071830_600954_971FA751 X-CRM114-Status: GOOD ( 29.85 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marc Zyngier , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Andre, On 2/17/21 4:48 PM, Alexandru Elisei wrote: > Hi Andre, > > On 12/10/20 2:29 PM, Andre Przywara wrote: >> Using the UART devices at their legacy I/O addresses as set by IBM in >> 1981 was a kludge we used for simplicity on ARM platforms as well. >> However this imposes problems due to their missing alignment and overlap >> with the PCI I/O address space. >> >> Now that we can switch a device easily between using ioports and MMIO, >> let's move the UARTs out of the first 4K of memory on ARM platforms. >> >> That should be transparent for well behaved guests, since the change is >> naturally reflected in the device tree. Even "earlycon" keeps working, >> as the stdout-path property is adjusted automatically. >> >> People providing direct earlycon parameters via the command line need to >> adjust it to: "earlycon=uart,mmio,0x1000000". >> >> Signed-off-by: Andre Przywara >> --- >> hw/serial.c | 52 ++++++++++++++++++++++++++++++++++++---------------- >> 1 file changed, 36 insertions(+), 16 deletions(-) >> >> diff --git a/hw/serial.c b/hw/serial.c >> index d840eebc..00fb3aa8 100644 >> --- a/hw/serial.c >> +++ b/hw/serial.c >> @@ -13,6 +13,24 @@ >> >> #include >> >> +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) >> +#define serial_iobase(nr) (0x1000000 + (nr) * 0x1000) >> +#define serial_irq(nr) (32 + (nr)) >> +#define SERIAL8250_BUS_TYPE DEVICE_BUS_MMIO >> +#else >> +#define serial_iobase_0 0x3f8 >> +#define serial_iobase_1 0x2f8 >> +#define serial_iobase_2 0x3e8 >> +#define serial_iobase_3 0x2e8 >> +#define serial_irq_0 4 >> +#define serial_irq_1 3 >> +#define serial_irq_2 4 >> +#define serial_irq_3 3 > Nitpick: serial_iobase_* and serial_irq_* could be changed to have two leading > underscores, to stress the fact that they are helpers for serial_iobase() and > serial_irq() and are not meant to be used by themselves. But that's just personal > preference, otherwise the patch looks really nice and clean: > > Reviewed-by: Alexandru Elisei I gave it more thought and I think I spoke too soon. I think it would be good to document in the commit message how you came to the base MMIO address and size (even if it was just a nice looking number). Also, the CFI flash device has its memory range described in the memory layout for the architecture, in arm/include/arm-common/kvm-arch.h. I think it would be a good idea to put the serial region there, to prevent regressions in the future. I did the math to make sure there's no overlap with the ioport region (16M >> 16K) or the flash region (16M + 0x4000 < 32M). I also tested the changes with a kernel with 4K and 64K pages (I can't access any hardware with 16K pages at the moment), and everything worked as expected. Thanks, Alex > Thanks, > > Alex > >> +#define serial_iobase(nr) serial_iobase_##nr >> +#define serial_irq(nr) serial_irq_##nr >> +#define SERIAL8250_BUS_TYPE DEVICE_BUS_IOPORT >> +#endif >> + >> /* >> * This fakes a U6_16550A. The fifo len needs to be 64 as the kernel >> * expects that for autodetection. >> @@ -27,7 +45,7 @@ struct serial8250_device { >> struct mutex mutex; >> u8 id; >> >> - u16 iobase; >> + u32 iobase; >> u8 irq; >> u8 irq_state; >> int txcnt; >> @@ -65,56 +83,56 @@ static struct serial8250_device devices[] = { >> /* ttyS0 */ >> [0] = { >> .dev_hdr = { >> - .bus_type = DEVICE_BUS_IOPORT, >> + .bus_type = SERIAL8250_BUS_TYPE, >> .data = serial8250_generate_fdt_node, >> }, >> .mutex = MUTEX_INITIALIZER, >> >> .id = 0, >> - .iobase = 0x3f8, >> - .irq = 4, >> + .iobase = serial_iobase(0), >> + .irq = serial_irq(0), >> >> SERIAL_REGS_SETTING >> }, >> /* ttyS1 */ >> [1] = { >> .dev_hdr = { >> - .bus_type = DEVICE_BUS_IOPORT, >> + .bus_type = SERIAL8250_BUS_TYPE, >> .data = serial8250_generate_fdt_node, >> }, >> .mutex = MUTEX_INITIALIZER, >> >> .id = 1, >> - .iobase = 0x2f8, >> - .irq = 3, >> + .iobase = serial_iobase(1), >> + .irq = serial_irq(1), >> >> SERIAL_REGS_SETTING >> }, >> /* ttyS2 */ >> [2] = { >> .dev_hdr = { >> - .bus_type = DEVICE_BUS_IOPORT, >> + .bus_type = SERIAL8250_BUS_TYPE, >> .data = serial8250_generate_fdt_node, >> }, >> .mutex = MUTEX_INITIALIZER, >> >> .id = 2, >> - .iobase = 0x3e8, >> - .irq = 4, >> + .iobase = serial_iobase(2), >> + .irq = serial_irq(2), >> >> SERIAL_REGS_SETTING >> }, >> /* ttyS3 */ >> [3] = { >> .dev_hdr = { >> - .bus_type = DEVICE_BUS_IOPORT, >> + .bus_type = SERIAL8250_BUS_TYPE, >> .data = serial8250_generate_fdt_node, >> }, >> .mutex = MUTEX_INITIALIZER, >> >> .id = 3, >> - .iobase = 0x2e8, >> - .irq = 3, >> + .iobase = serial_iobase(3), >> + .irq = serial_irq(3), >> >> SERIAL_REGS_SETTING >> }, >> @@ -444,7 +462,8 @@ static int serial8250__device_init(struct kvm *kvm, >> return r; >> >> ioport__map_irq(&dev->irq); >> - r = kvm__register_pio(kvm, dev->iobase, 8, serial8250_mmio, dev); >> + r = kvm__register_iotrap(kvm, dev->iobase, 8, serial8250_mmio, dev, >> + SERIAL8250_BUS_TYPE); >> >> return r; >> } >> @@ -467,7 +486,7 @@ cleanup: >> for (j = 0; j <= i; j++) { >> struct serial8250_device *dev = &devices[j]; >> >> - kvm__deregister_pio(kvm, dev->iobase); >> + kvm__deregister_iotrap(kvm, dev->iobase, SERIAL8250_BUS_TYPE); >> device__unregister(&dev->dev_hdr); >> } >> >> @@ -483,7 +502,8 @@ int serial8250__exit(struct kvm *kvm) >> for (i = 0; i < ARRAY_SIZE(devices); i++) { >> struct serial8250_device *dev = &devices[i]; >> >> - r = kvm__deregister_pio(kvm, dev->iobase); >> + r = kvm__deregister_iotrap(kvm, dev->iobase, >> + SERIAL8250_BUS_TYPE); >> if (r < 0) >> return r; >> device__unregister(&dev->dev_hdr); > _______________________________________________ > kvmarm mailing list > kvmarm@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel