From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3wPHJZ5HLWzDqbm for ; Fri, 12 May 2017 14:37:34 +1000 (AEST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4C4YEOC131408 for ; Fri, 12 May 2017 00:37:31 -0400 Received: from e23smtp02.au.ibm.com (e23smtp02.au.ibm.com [202.81.31.144]) by mx0b-001b2d01.pphosted.com with ESMTP id 2acrqhjh36-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 12 May 2017 00:37:31 -0400 Received: from localhost by e23smtp02.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 12 May 2017 14:37:28 +1000 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4C4bJMo61472994 for ; Fri, 12 May 2017 14:37:27 +1000 Received: from d23av04.au.ibm.com (localhost [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v4C4aq3x025042 for ; Fri, 12 May 2017 14:36:53 +1000 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 MIME-Version: 1.0 In-Reply-To: <87wp9nj0ji.fsf@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 > >