From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756199AbdELEhe (ORCPT ); Fri, 12 May 2017 00:37:34 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51472 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755662AbdELEhd (ORCPT ); Fri, 12 May 2017 00:37:33 -0400 Subject: Re: [PATCH v8 02/10] powerpc/powernv: Autoload IMC device driver module To: Stewart Smith , Anju T Sudhakar , mpe@ellerman.id.au References: <1493907596-11425-1-git-send-email-anju@linux.vnet.ibm.com> <1493907596-11425-3-git-send-email-anju@linux.vnet.ibm.com> <87wp9nj0ji.fsf@linux.vnet.ibm.com> Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, ego@linux.vnet.ibm.com, bsingharora@gmail.com, anton@samba.org, sukadev@linux.vnet.ibm.com, mikey@neuling.org, dja@axtens.net, eranian@google.com, hemant@linux.vnet.ibm.com From: Madhavan Srinivasan Date: Fri, 12 May 2017 10:06:26 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <87wp9nj0ji.fsf@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable x-cbid: 17051204-0048-0000-0000-0000022C66B7 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17051204-0049-0000-0000-000047DAC9DB Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-05-12_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705120089 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 11 May 2017 01:19 PM, Stewart Smith wrote: > Anju T Sudhakar writes: >> This patch does three things : >> - Enables "opal.c" to create a platform device for the IMC interface >> according to the appropriate compatibility string. >> - Find the reserved-memory region details from the system device tree >> and get the base address of HOMER (Reserved memory) region address for each chip. >> - We also get the Nest PMU counter data offsets (in the HOMER region) >> and their sizes. The offsets for the counters' data are fixed and >> won't change from chip to chip. >> >> The device tree parsing logic is separated from the PMU creation >> functions (which is done in subsequent patches). >> >> Patch also adds a CONFIG_HV_PERF_IMC_CTRS for the IMC driver. >> >> Signed-off-by: Anju T Sudhakar >> Signed-off-by: Hemant Kumar >> Signed-off-by: Madhavan Srinivasan >> --- >> arch/powerpc/platforms/powernv/Kconfig | 10 +++ >> arch/powerpc/platforms/powernv/Makefile | 1 + >> arch/powerpc/platforms/powernv/opal-imc.c | 140 ++++++++++++++++++++++++++++++ >> arch/powerpc/platforms/powernv/opal.c | 18 ++++ >> 4 files changed, 169 insertions(+) >> create mode 100644 arch/powerpc/platforms/powernv/opal-imc.c >> >> diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platforms/powernv/Kconfig >> index 3a07e4d..1b90a98 100644 >> --- a/arch/powerpc/platforms/powernv/Kconfig >> +++ b/arch/powerpc/platforms/powernv/Kconfig >> @@ -27,3 +27,13 @@ config OPAL_PRD >> help >> This enables the opal-prd driver, a facility to run processor >> recovery diagnostics on OpenPower machines >> + >> +config HV_PERF_IMC_CTRS >> + bool "Hypervisor supplied In Memory Collection PMU events (Nest & Core)" >> + default y >> + depends on PERF_EVENTS && PPC_POWERNV >> + help >> + Enable access to hypervisor supplied in-memory collection counters >> + in perf. IMC counters are available from Power9 systems. >> + >> + If unsure, select Y. >> diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile >> index b5d98cb..715e531 100644 >> --- a/arch/powerpc/platforms/powernv/Makefile >> +++ b/arch/powerpc/platforms/powernv/Makefile >> @@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM) += opal-xscom.o >> obj-$(CONFIG_MEMORY_FAILURE) += opal-memory-errors.o >> obj-$(CONFIG_TRACEPOINTS) += opal-tracepoints.o >> obj-$(CONFIG_OPAL_PRD) += opal-prd.o >> +obj-$(CONFIG_HV_PERF_IMC_CTRS) += opal-imc.o >> diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c >> new file mode 100644 >> index 0000000..3a87000 >> --- /dev/null >> +++ b/arch/powerpc/platforms/powernv/opal-imc.c >> @@ -0,0 +1,140 @@ >> +/* >> + * OPAL IMC interface detection driver >> + * Supported on POWERNV platform >> + * >> + * Copyright (C) 2017 Madhavan Srinivasan, IBM Corporation. >> + * (C) 2017 Anju T Sudhakar, IBM Corporation. >> + * (C) 2017 Hemant K Shaw, IBM Corporation. >> + * >> + * 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. >> + */ >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +struct perchip_nest_info nest_perchip_info[IMC_MAX_CHIPS]; >> + >> +/* >> + * imc_pmu_setup : Setup the IMC PMUs (children of "parent"). >> + */ >> +static void __init imc_pmu_setup(struct device_node *parent) >> +{ >> + if (!parent) >> + return; >> +} >> + >> +static int opal_imc_counters_probe(struct platform_device *pdev) >> +{ >> + struct device_node *imc_dev, *dn, *rm_node = NULL; >> + struct perchip_nest_info *pcni; >> + u32 pages, nest_offset, nest_size, chip_id; >> + int i = 0; >> + const __be32 *addrp; >> + u64 reg_addr, reg_size; >> + >> + if (!pdev || !pdev->dev.of_node) >> + return -ENODEV; >> + >> + /* >> + * Check whether this is kdump kernel. If yes, just return. >> + */ >> + if (is_kdump_kernel()) >> + return -ENODEV; >> + >> + imc_dev = pdev->dev.of_node; >> + >> + /* >> + * Nest counter data are saved in a reserved memory called HOMER. >> + * "imc-nest-offset" identifies the counter data location within HOMER. >> + * size : size of the entire nest-counters region >> + */ >> + if (of_property_read_u32(imc_dev, "imc-nest-offset", &nest_offset)) >> + goto err; >> + >> + if (of_property_read_u32(imc_dev, "imc-nest-size", &nest_size)) >> + goto err; >> + >> + /* Sanity check */ >> + if ((nest_size/PAGE_SIZE) > IMC_NEST_MAX_PAGES) >> + goto err; >> + >> + /* Find the "HOMER region" for each chip */ >> + rm_node = of_find_node_by_path("/reserved-memory"); >> + if (!rm_node) >> + goto err; >> + >> + /* >> + * We need to look for the "ibm,homer-image" node in the >> + * "/reserved-memory" node. >> + */ >> + for (dn = of_find_node_by_name(rm_node, "ibm,homer-image"); dn; >> + dn = of_find_node_by_name(dn, "ibm,homer-image")) { >> + >> + /* Get the chip id to which the above homer region belongs to */ >> + if (of_property_read_u32(dn, "ibm,chip-id", &chip_id)) >> + goto err; > So, I was thinking on this (and should probably comment on the firmware > side as well). > > I'd prefer an OPAL interface where instead of looking up where > ibm,homer-image is, we provide the kernel with a base address and then > have offsets into it. > > That way, we don't tie the kernel code to counters that are only in the > HOMER region. Yes. This make sense. Adding something like this to IMC node will be fine? chip@ { base_addr = < addr >; ibm,chip-id = < id>; }; Maddy > >