From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Nowicki Subject: Re: [PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support Date: Wed, 22 Jun 2016 13:06:05 +0200 Message-ID: <576A711D.5080206@semihalf.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> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-lf0-f41.google.com ([209.85.215.41]:33473 "EHLO mail-lf0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751438AbcFVLGL (ORCPT ); Wed, 22 Jun 2016 07:06:11 -0400 Received: by mail-lf0-f41.google.com with SMTP id f6so71450568lfg.0 for ; Wed, 22 Jun 2016 04:06:09 -0700 (PDT) In-Reply-To: <576A6D7F.6010407@arm.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Marc Zyngier , 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 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 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? Tomasz From mboxrd@z Thu Jan 1 00:00:00 1970 From: tn@semihalf.com (Tomasz Nowicki) Date: Wed, 22 Jun 2016 13:06:05 +0200 Subject: [PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support In-Reply-To: <576A6D7F.6010407@arm.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> Message-ID: <576A711D.5080206@semihalf.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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? Tomasz