From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751849AbdHQDpt (ORCPT ); Wed, 16 Aug 2017 23:45:49 -0400 Received: from mail-ua0-f174.google.com ([209.85.217.174]:38545 "EHLO mail-ua0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751642AbdHQDpr (ORCPT ); Wed, 16 Aug 2017 23:45:47 -0400 MIME-Version: 1.0 In-Reply-To: <20170810132338.406b06ce@w520.home> References: <1501652310-3638-1-git-send-email-anup.patel@broadcom.com> <1501652310-3638-2-git-send-email-anup.patel@broadcom.com> <20170810132338.406b06ce@w520.home> From: Anup Patel Date: Thu, 17 Aug 2017 09:15:46 +0530 Message-ID: Subject: Re: [PATCH v4] vfio: platform: reset: Add Broadcom FlexRM reset module To: Alex Williamson Cc: Will Deacon , Robin Murphy , Joerg Roedel , Baptiste Reynal , Scott Branden , Linux Kernel , Linux ARM Kernel , Linux IOMMU , kvm@vger.kernel.org, BCM Kernel Feedback Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 11, 2017 at 12:53 AM, Alex Williamson wrote: > On Wed, 2 Aug 2017 11:08:30 +0530 > Anup Patel wrote: > >> This patch adds Broadcom FlexRM low-level reset for >> VFIO platform. >> >> It will do the following: >> 1. Disable/Deactivate each FlexRM ring >> 2. Flush each FlexRM ring >> >> The cleanup sequence for FlexRM rings is adapted from >> Broadcom FlexRM mailbox driver. >> >> Signed-off-by: Anup Patel >> Reviewed-by: Oza Oza >> Reviewed-by: Scott Branden >> Reviewed-by: Eric Auger >> --- >> drivers/vfio/platform/reset/Kconfig | 8 ++ >> drivers/vfio/platform/reset/Makefile | 1 + >> .../vfio/platform/reset/vfio_platform_bcmflexrm.c | 100 +++++++++++++++++++++ >> 3 files changed, 109 insertions(+) >> create mode 100644 drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c >> >> diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig >> index 70cccc5..8833805 100644 >> --- a/drivers/vfio/platform/reset/Kconfig >> +++ b/drivers/vfio/platform/reset/Kconfig >> @@ -13,3 +13,11 @@ config VFIO_PLATFORM_AMDXGBE_RESET >> Enables the VFIO platform driver to handle reset for AMD XGBE >> >> If you don't know what to do here, say N. >> + >> +config VFIO_PLATFORM_BCMFLEXRM_RESET >> + tristate "VFIO support for Broadcom FlexRM reset" >> + depends on VFIO_PLATFORM && (ARCH_BCM_IPROC || COMPILE_TEST) >> + help >> + Enables the VFIO platform driver to handle reset for Broadcom FlexRM >> + >> + If you don't know what to do here, say N. >> diff --git a/drivers/vfio/platform/reset/Makefile b/drivers/vfio/platform/reset/Makefile >> index 93f4e23..8d9874b 100644 >> --- a/drivers/vfio/platform/reset/Makefile >> +++ b/drivers/vfio/platform/reset/Makefile >> @@ -5,3 +5,4 @@ ccflags-y += -Idrivers/vfio/platform >> >> obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o >> obj-$(CONFIG_VFIO_PLATFORM_AMDXGBE_RESET) += vfio-platform-amdxgbe.o >> +obj-$(CONFIG_VFIO_PLATFORM_BCMFLEXRM_RESET) += vfio_platform_bcmflexrm.o >> diff --git a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c >> new file mode 100644 >> index 0000000..104c3c1 >> --- /dev/null >> +++ b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c >> @@ -0,0 +1,100 @@ >> +/* >> + * Copyright (C) 2017 Broadcom >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 as >> + * published by the Free Software Foundation. >> + * >> + * This program is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> + * GNU General Public License for more details. >> + * >> + * You should have received a copy of the GNU General Public License >> + * along with this program. If not, see . >> + */ >> + >> +/* >> + * This driver provides reset support for Broadcom FlexRM ring manager >> + * to VFIO platform. >> + */ >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#include "vfio_platform_private.h" >> + >> +/* FlexRM configuration */ >> +#define RING_REGS_SIZE 0x10000 >> +#define RING_VER_MAGIC 0x76303031 >> + >> +/* Per-Ring register offsets */ >> +#define RING_VER 0x000 >> +#define RING_CONTROL 0x034 >> +#define RING_FLUSH_DONE 0x038 >> + >> +/* Register RING_CONTROL fields */ >> +#define CONTROL_FLUSH_SHIFT 5 >> + >> +/* Register RING_FLUSH_DONE fields */ >> +#define FLUSH_DONE_MASK 0x1 >> + >> +static int vfio_platform_bcmflexrm_shutdown(void __iomem *ring) >> +{ >> + unsigned int timeout; >> + >> + /* Disable/inactivate ring */ >> + writel_relaxed(0x0, ring + RING_CONTROL); >> + >> + /* Flush ring with timeout of 1s */ >> + timeout = 1000; >> + writel_relaxed(BIT(CONTROL_FLUSH_SHIFT), ring + RING_CONTROL); >> + do { >> + if (readl_relaxed(ring + RING_FLUSH_DONE) & FLUSH_DONE_MASK) >> + break; >> + mdelay(1); >> + } while (timeout--); >> + >> + if (!timeout) { >> + pr_warn("VFIO FlexRM shutdown timeout\n"); >> + return -ETIMEDOUT; >> + } > > > This doesn't work, timeout is ~0 here. Sure, I will use "--timeout" instead of "timeout--" which will fix the issue. Thanks for pointing. Regards, Anup