From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422939AbcFGUPJ (ORCPT ); Tue, 7 Jun 2016 16:15:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46387 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1162054AbcFGUPG (ORCPT ); Tue, 7 Jun 2016 16:15:06 -0400 Subject: Re: [PATCH V6 5/8] vfio: platform: call _RST method when using ACPI To: Sinan Kaya , kvm@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, jcm@redhat.com, eric.auger@linaro.org References: <1464472878-27176-1-git-send-email-okaya@codeaurora.org> <1464472878-27176-6-git-send-email-okaya@codeaurora.org> Cc: linux-acpi@vger.kernel.org, agross@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Baptiste Reynal , Alex Williamson , linux-kernel@vger.kernel.org From: Auger Eric Message-ID: Date: Tue, 7 Jun 2016 22:14:56 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <1464472878-27176-6-git-send-email-okaya@codeaurora.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 07 Jun 2016 20:15:05 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sinan, Le 29/05/2016 à 00:01, Sinan Kaya a écrit : > The device tree code checks for the presence of a reset driver and calls > the of_reset function pointer by looking up the reset driver as a module. > > ACPI defines _RST method to perform device level reset. After the _RST > method is executed, the OS can resume using the device. _RST method is > expected to stop DMA transfers and IRQs. > > This patch checks the presence of _RST method and calls the _RST > method when reset is requested. > > Signed-off-by: Sinan Kaya > Reviewed-by: Eric Auger code has changed compared to previous version and the R-b. In the future, please add change logs. Besides it looks ok to me. Best Regards Eric > --- > drivers/vfio/platform/vfio_platform_common.c | 51 ++++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > > diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c > index e7ce2c2..0ea8c26 100644 > --- a/drivers/vfio/platform/vfio_platform_common.c > +++ b/drivers/vfio/platform/vfio_platform_common.c > @@ -73,21 +73,66 @@ static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev, > } > return 0; > } > + > +static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev, > + const char **extra_dbg) > +{ > + struct device *dev = vdev->device; > + acpi_handle handle = ACPI_HANDLE(dev); > + acpi_status acpi_ret; > + unsigned long long val; > + > + acpi_ret = acpi_evaluate_integer(handle, "_RST", NULL, &val); > + if (ACPI_FAILURE(acpi_ret)) { > + if (extra_dbg) > + *extra_dbg = acpi_format_exception(acpi_ret); > + return -EINVAL; > + } > + > + return 0; > +} > + > +static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev) > +{ > + struct device *dev = vdev->device; > + acpi_handle handle = ACPI_HANDLE(dev); > + > + return acpi_has_method(handle, "_RST"); > +} > #else > static inline int vfio_platform_acpi_probe(struct vfio_platform_device *vdev, > struct device *dev) > { > return -ENOENT; > } > + > +static inline > +int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev, > + const char **extra_dbg) > +{ > + return -ENOENT; > +} > + > +static inline > +bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev) > +{ > + return false; > +} > #endif > > static bool vfio_platform_has_reset(struct vfio_platform_device *vdev) > { > + if (vdev->acpihid) > + return vfio_platform_acpi_has_reset(vdev); > + > return vdev->of_reset ? true : false; > } > > static void vfio_platform_get_reset(struct vfio_platform_device *vdev) > { > + if (vdev->acpihid) > + return; > + > vdev->of_reset = vfio_platform_lookup_reset(vdev->compat, > &vdev->reset_module); > if (!vdev->of_reset) { > @@ -99,6 +144,9 @@ static void vfio_platform_get_reset(struct vfio_platform_device *vdev) > > static void vfio_platform_put_reset(struct vfio_platform_device *vdev) > { > + if (vdev->acpihid) > + return; > + > if (vdev->of_reset) > module_put(vdev->reset_module); > } > @@ -177,6 +225,9 @@ static int vfio_platform_call_reset(struct vfio_platform_device *vdev, > if (vdev->of_reset) { > dev_info(vdev->device, "reset\n"); > return vdev->of_reset(vdev); > + } else if (vdev->acpihid) { > + dev_info(vdev->device, "reset\n"); > + return vfio_platform_acpi_call_reset(vdev, extra_dbg); > } > > dev_warn(vdev->device, "no reset function found!\n"); >