From patchwork Thu Dec 10 14:29:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andre Przywara X-Patchwork-Id: 11965935 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E996CC433FE for ; Thu, 10 Dec 2020 19:04:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B04EC23440 for ; Thu, 10 Dec 2020 19:04:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390479AbgLJTEi (ORCPT ); Thu, 10 Dec 2020 14:04:38 -0500 Received: from foss.arm.com ([217.140.110.172]:45078 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390489AbgLJObZ (ORCPT ); Thu, 10 Dec 2020 09:31:25 -0500 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 AD01A1595; Thu, 10 Dec 2020 06:29:49 -0800 (PST) Received: from donnerap.arm.com (donnerap.cambridge.arm.com [10.1.195.35]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 93AC63F718; Thu, 10 Dec 2020 06:29:48 -0800 (PST) From: Andre Przywara To: Will Deacon , Julien Thierry Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Alexandru Elisei , Marc Zyngier Subject: [PATCH kvmtool 21/21] hw/rtc: ARM/arm64: Use MMIO at higher addresses Date: Thu, 10 Dec 2020 14:29:08 +0000 Message-Id: <20201210142908.169597-22-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201210142908.169597-1-andre.przywara@arm.com> References: <20201210142908.169597-1-andre.przywara@arm.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Using the RTC device at its legacy I/O address 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 RTC 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. Signed-off-by: Andre Przywara --- hw/rtc.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/hw/rtc.c b/hw/rtc.c index ee4c9102..bdb88f0f 100644 --- a/hw/rtc.c +++ b/hw/rtc.c @@ -5,6 +5,15 @@ #include +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) +#define RTC_BUS_TYPE DEVICE_BUS_MMIO +#define RTC_BASE_ADDRESS 0x1010000 +#else +/* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */ +#define RTC_BUS_TYPE DEVICE_BUS_IOPORT +#define RTC_BASE_ADDRESS 0x70 +#endif + /* * MC146818 RTC registers */ @@ -49,7 +58,7 @@ static void cmos_ram_io(struct kvm_cpu *vcpu, u64 addr, u8 *data, time_t ti; if (is_write) { - if (addr == 0x70) { /* index register */ + if (addr == RTC_BASE_ADDRESS) { /* index register */ u8 value = ioport__read8(data); vcpu->kvm->nmi_disabled = value & (1UL << 7); @@ -70,7 +79,7 @@ static void cmos_ram_io(struct kvm_cpu *vcpu, u64 addr, u8 *data, return; } - if (addr == 0x70) + if (addr == RTC_BASE_ADDRESS) /* index register is write-only */ return; time(&ti); @@ -127,7 +136,7 @@ static void generate_rtc_fdt_node(void *fdt, u8 irq, enum irq_type)) { - u64 reg_prop[2] = { cpu_to_fdt64(0x70), cpu_to_fdt64(2) }; + u64 reg_prop[2] = { cpu_to_fdt64(RTC_BASE_ADDRESS), cpu_to_fdt64(2) }; _FDT(fdt_begin_node(fdt, "rtc")); _FDT(fdt_property_string(fdt, "compatible", "motorola,mc146818")); @@ -139,7 +148,7 @@ static void generate_rtc_fdt_node(void *fdt, #endif struct device_header rtc_dev_hdr = { - .bus_type = DEVICE_BUS_IOPORT, + .bus_type = RTC_BUS_TYPE, .data = generate_rtc_fdt_node, }; @@ -151,8 +160,8 @@ int rtc__init(struct kvm *kvm) if (r < 0) return r; - /* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */ - r = kvm__register_pio(kvm, 0x0070, 2, cmos_ram_io, NULL); + r = kvm__register_iotrap(kvm, RTC_BASE_ADDRESS, 2, cmos_ram_io, NULL, + RTC_BUS_TYPE); if (r < 0) goto out_device; @@ -170,8 +179,7 @@ dev_init(rtc__init); int rtc__exit(struct kvm *kvm) { - /* PORT 0070-007F - CMOS RAM/RTC (REAL TIME CLOCK) */ - kvm__deregister_pio(kvm, 0x0070); + kvm__deregister_iotrap(kvm, RTC_BASE_ADDRESS, RTC_BUS_TYPE); return 0; }