From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49573) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ccFc8-00021a-BO for qemu-devel@nongnu.org; Fri, 10 Feb 2017 13:08:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ccFc7-0003wq-FZ for qemu-devel@nongnu.org; Fri, 10 Feb 2017 13:08:08 -0500 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:48481) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ccFc7-0003vW-89 for qemu-devel@nongnu.org; Fri, 10 Feb 2017 13:08:07 -0500 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1ccFc6-0007cL-Do for qemu-devel@nongnu.org; Fri, 10 Feb 2017 18:08:06 +0000 From: Peter Maydell Date: Fri, 10 Feb 2017 18:07:55 +0000 Message-Id: <1486750082-12324-6-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1486750082-12324-1-git-send-email-peter.maydell@linaro.org> References: <1486750082-12324-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PULL 05/12] target-arm: Declare virtio-mmio as dma-coherent in dt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org From: Alexander Graf QEMU emulated hardware is always dma coherent with its guest. We do annotate that correctly on the PCI host controller, but left out virtio-mmio. Recent kernels have started to interpret that flag rather than take dma coherency as granted with virtio-mmio. While that is considered a kernel bug, as it breaks previously working systems, it showed that our dt description is incomplete. This patch adds the respective marker that allows guest OSs to evaluate that our virtio-mmio devices are indeed cache coherent. Signed-off-by: Alexander Graf Reviewed-by: Laszlo Ersek Reviewed-by: Ard Biesheuvel Message-id: 1486644810-33181-2-git-send-email-agraf@suse.de Signed-off-by: Peter Maydell --- hw/arm/vexpress.c | 1 + hw/arm/virt.c | 1 + 2 files changed, 2 insertions(+) diff --git a/hw/arm/vexpress.c b/hw/arm/vexpress.c index 58760f4..e057568 100644 --- a/hw/arm/vexpress.c +++ b/hw/arm/vexpress.c @@ -452,6 +452,7 @@ static int add_virtio_mmio_node(void *fdt, uint32_t acells, uint32_t scells, acells, addr, scells, size); qemu_fdt_setprop_cells(fdt, nodename, "interrupt-parent", intc); qemu_fdt_setprop_cells(fdt, nodename, "interrupts", 0, irq, 1); + qemu_fdt_setprop(fdt, nodename, "dma-coherent", NULL, 0); g_free(nodename); if (rc) { return -1; diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 8eef143..d20e627 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -797,6 +797,7 @@ static void create_virtio_devices(const VirtMachineState *vms, qemu_irq *pic) qemu_fdt_setprop_cells(vms->fdt, nodename, "interrupts", GIC_FDT_IRQ_TYPE_SPI, irq, GIC_FDT_IRQ_FLAGS_EDGE_LO_HI); + qemu_fdt_setprop(vms->fdt, nodename, "dma-coherent", NULL, 0); g_free(nodename); } } -- 2.7.4