From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x243.google.com (mail-pf0-x243.google.com [IPv6:2607:f8b0:400e:c00::243]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3vXW9c1G5gzDqGw for ; Tue, 28 Feb 2017 18:56:20 +1100 (AEDT) Received: by mail-pf0-x243.google.com with SMTP id y23so613713pfk.2 for ; Mon, 27 Feb 2017 23:56:20 -0800 (PST) Received: from matt.gateway ([2001:8003:181f:fa00:97a:a923:bc9c:c5e4]) by smtp.gmail.com with ESMTPSA id m74sm2202802pfk.41.2017.02.27.23.56.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 Feb 2017 23:56:17 -0800 (PST) From: Matt Brown To: linuxppc-dev@lists.ozlabs.org Subject: [Patch v4] powerpc/powernv: add hdat attribute to sysfs Date: Tue, 28 Feb 2017 18:55:03 +1100 Message-Id: <20170228075503.20387-1-matthew.brown.dev@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The HDAT data area is consumed by skiboot and turned into a device-tree. In some cases we would like to look directly at the HDAT, so this patch adds a sysfs node to allow it to be viewed. This is not possible through /dev/mem as it is reserved memory which is stopped by the /dev/mem filter. Signed-off-by: Matt Brown --- Changes between v3 and v4: - changed sysfs attribute permissions from 0444 to 0400 - fixed makefile to be on same line - fixed authorship/copyright info - re-ordered includes - changed hdat_info struct to a static struct --- arch/powerpc/include/asm/opal.h | 1 + arch/powerpc/platforms/powernv/Makefile | 2 +- arch/powerpc/platforms/powernv/opal-hdat.c | 60 ++++++++++++++++++++++++++++++ arch/powerpc/platforms/powernv/opal.c | 2 + 4 files changed, 64 insertions(+), 1 deletion(-) create mode 100644 arch/powerpc/platforms/powernv/opal-hdat.c diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index 5c7db0f..b26944e 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -277,6 +277,7 @@ extern int opal_async_comp_init(void); extern int opal_sensor_init(void); extern int opal_hmi_handler_init(void); extern int opal_event_init(void); +extern void opal_hdat_sysfs_init(void); extern int opal_machine_check(struct pt_regs *regs); extern bool opal_mce_check_early_recovery(struct pt_regs *regs); diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile index b5d98cb..3826b70 100644 --- a/arch/powerpc/platforms/powernv/Makefile +++ b/arch/powerpc/platforms/powernv/Makefile @@ -2,7 +2,7 @@ obj-y += setup.o opal-wrappers.o opal.o opal-async.o idle.o obj-y += opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o obj-y += rng.o opal-elog.o opal-dump.o opal-sysparam.o opal-sensor.o obj-y += opal-msglog.o opal-hmi.o opal-power.o opal-irqchip.o -obj-y += opal-kmsg.o +obj-y += opal-kmsg.o opal-hdat.o obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o obj-$(CONFIG_PCI) += pci.o pci-ioda.o npu-dma.o diff --git a/arch/powerpc/platforms/powernv/opal-hdat.c b/arch/powerpc/platforms/powernv/opal-hdat.c new file mode 100644 index 0000000..19647fd --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal-hdat.c @@ -0,0 +1,60 @@ +/* + * PowerNV OPAL HDAT interface + * + * Copyright 2017, Matt Brown, IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include + +static struct { + char *base; + u64 size; +} hdat_info; + +/* Read function for HDAT attribute in sysfs */ +static ssize_t hdat_read(struct file *file, struct kobject *kobj, + struct bin_attribute *bin_attr, char *to, + loff_t pos, size_t count) +{ + if (!hdat_info.base) + return -ENODEV; + + return memory_read_from_buffer(to, count, &pos, hdat_info.base, + hdat_info.size); +} + +/* HDAT attribute for sysfs */ +static struct bin_attribute hdat_attr = { + .attr = {.name = "hdat", .mode = 0400}, + .read = hdat_read +}; + +void __init opal_hdat_sysfs_init(void) +{ + u64 hdat_addr[2]; + + /* Check for the hdat-map prop in device-tree */ + if (of_property_read_u64_array(opal_node, "hdat-map", hdat_addr, 2)) { + pr_debug("OPAL: Property hdat-map not found.\n"); + return; + } + + /* Print out hdat-map values. [0]: base, [1]: size */ + pr_debug("OPAL: HDAT Base address: %#llx\n", hdat_addr[0]); + pr_debug("OPAL: HDAT Size: %#llx\n", hdat_addr[1]); + + hdat_info.base = phys_to_virt(hdat_addr[0]); + hdat_info.size = hdat_addr[1]; + + if (sysfs_create_bin_file(opal_kobj, &hdat_attr)) + pr_debug("OPAL: sysfs file creation for HDAT failed"); + +} diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 2822935..cae3745 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -740,6 +740,8 @@ static int __init opal_init(void) opal_sys_param_init(); /* Setup message log sysfs interface. */ opal_msglog_sysfs_init(); + /* Create hdat object under sys/firmware/opal */ + opal_hdat_sysfs_init(); } /* Initialize platform devices: IPMI backend, PRD & flash interface */ -- 2.9.3