From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752639AbcFVMER (ORCPT ); Wed, 22 Jun 2016 08:04:17 -0400 Received: from foss.arm.com ([217.140.101.70]:47118 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752510AbcFVMEN (ORCPT ); Wed, 22 Jun 2016 08:04:13 -0400 Subject: Re: [PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support To: Tomasz Nowicki , Hanjun Guo , tglx@linutronix.de, jason@lakedaemon.net, rjw@rjwysocki.net, bhelgaas@google.com, lorenzo.pieralisi@arm.com, robert.richter@caviumnetworks.com, shijie.huang@arm.com, Suravee.Suthikulpanit@amd.com References: <1466420541-20101-1-git-send-email-tn@semihalf.com> <1466420541-20101-2-git-send-email-tn@semihalf.com> <372d3b78-2bc5-94d1-49f6-c9229affa65d@linaro.org> <576A6D7F.6010407@arm.com> <576A711D.5080206@semihalf.com> Cc: al.stone@linaro.org, mw@semihalf.com, graeme.gregory@linaro.org, Catalin.Marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, ddaney.cavm@gmail.com, okaya@codeaurora.org, andrea.gallo@linaro.org, linux-pci@vger.kernel.org From: Marc Zyngier Organization: ARM Ltd Message-ID: <576A7E98.4060502@arm.com> Date: Wed, 22 Jun 2016 13:03:36 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.7.0 MIME-Version: 1.0 In-Reply-To: <576A711D.5080206@semihalf.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/06/16 12:06, Tomasz Nowicki wrote: > On 22.06.2016 12:50, Marc Zyngier wrote: >> On 21/06/16 08:12, Hanjun Guo wrote: >>> Hi Tomasz, >>> >>> Sorry for jumping out late, just one comment below. >>> >>> On 2016/6/20 19:02, Tomasz Nowicki wrote: >>>> IORT shows representation of IO topology for ARM based systems. >>>> It describes how various components are connected together on >>>> parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec. >>>> >>>> Initial support allows to detect IORT table presence and save its >>>> root pointer obtained through acpi_get_table(). The pointer validity >>>> depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap >>>> is not set while using IORT nodes we would dereference unmapped pointers. >>>> >>>> For the aforementioned reason call iort_table_detect() from acpi_init() >>>> which guarantees acpi_gbl_permanent_mmap to be set at that point. >>>> >>>> Add generic helpers which are helpful for scanning and retrieving >>>> information from IORT table content. List of the most important helpers: >>>> - iort_find_dev_node() finds IORT node for a given device >>>> - iort_node_map_rid() maps device RID and returns IORT node which provides >>>> final translation >>>> >>>> Signed-off-by: Tomasz Nowicki >>>> --- >>>> drivers/acpi/Kconfig | 3 + >>>> drivers/acpi/Makefile | 1 + >>>> drivers/acpi/bus.c | 2 + >>>> drivers/acpi/iort.c | 220 ++++++++++++++++++++++++++++++++++++++++++++++++++ >>>> include/linux/iort.h | 30 +++++++ >>> >>> [...] >>> >>>> +static acpi_status >>>> +iort_match_node_callback(struct acpi_iort_node *node, void *context) >>>> +{ >>>> + struct device *dev = context; >>>> + >>>> + switch (node->type) { >>>> + case ACPI_IORT_NODE_NAMED_COMPONENT: { >>>> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; >>> >>> ACPI_ALLOCATE_BUFFER is used here, so ... >>> >>>> + struct acpi_device *adev = to_acpi_device_node(dev->fwnode); >>>> + struct acpi_iort_named_component *ncomp; >>>> + >>>> + if (!adev) >>>> + break; >>>> + >>>> + ncomp = (struct acpi_iort_named_component *)node->node_data; >>>> + >>>> + if (ACPI_FAILURE(acpi_get_name(adev->handle, >>>> + ACPI_FULL_PATHNAME, &buffer))) { >>>> + dev_warn(dev, "Can't get device full path name\n"); >>>> + break; >>>> + } >>>> + >>>> + if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) >>>> + return AE_OK; >>> >>> ... we need to kfree(buffer.pointer) before we return or break. >> >> For the record, I've queued this patch on top: >> >> diff --git a/drivers/acpi/iort.c b/drivers/acpi/iort.c >> index 496dcf6..3b9e55b 100644 >> --- a/drivers/acpi/iort.c >> +++ b/drivers/acpi/iort.c >> @@ -158,11 +158,15 @@ iort_match_node_callback(struct acpi_iort_node *node, void *context) >> if (ACPI_FAILURE(acpi_get_name(adev->handle, >> ACPI_FULL_PATHNAME, &buffer))) { >> dev_warn(dev, "Can't get device full path name\n"); >> - break; >> - } >> + } else { >> + int match; >> >> - if (!strcmp(ncomp->device_name, (char *)buffer.pointer)) >> - return AE_OK; >> + match = !strcmp(ncomp->device_name, buffer.pointer); >> + acpi_os_free(&buffer); >> + >> + if (match) >> + return AE_OK; >> + } >> >> break; >> } >> >> >> assuming that Rafael is OK with the general approach, of course. >> > > Thanks Marc. As Lorenzo pointed out, we need another fix for > iort_node_map_rid(). Do you want me to refresh the whole series or this > patch only? If the changes are localized enough, just this patch. Thanks, M. -- Jazz is not dead. It just smells funny...