From 9d64fc08f6fe59a7d71e84f650dd2c0f080254dd Mon Sep 17 00:00:00 2001 From: Mario Limonciello Date: Wed, 1 Nov 2017 14:25:37 -0500 Subject: [PATCH] tools/wmi: add a sample for dell smbios communication over WMI This application uses the character device /dev/wmi/dell-smbios to perform SMBIOS communications from userspace. It offers demonstrations of a few simple tasks: - Running a class/select command - Querying a token value - Activating a token Signed-off-by: Mario Limonciello Reviewed-by: Edward O'Callaghan Signed-off-by: Darren Hart (VMware) --- MAINTAINERS | 1 + tools/Makefile | 14 +-- tools/wmi/Makefile | 18 ++++ tools/wmi/dell-smbios-example.c | 210 ++++++++++++++++++++++++++++++++++++++++ 4 files changed, 237 insertions(+), 6 deletions(-) create mode 100644 tools/wmi/Makefile create mode 100644 tools/wmi/dell-smbios-example.c diff --git a/MAINTAINERS b/MAINTAINERS index 3af0750..da1851f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3997,6 +3997,7 @@ M: Mario Limonciello L: platform-driver-x86@vger.kernel.org S: Maintained F: drivers/platform/x86/dell-smbios-wmi.c +F: tools/wmi/dell-smbios-example.c DELL LAPTOP DRIVER M: Matthew Garrett diff --git a/tools/Makefile b/tools/Makefile index 9dfede3..9d2fd26 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -29,6 +29,7 @@ help: @echo ' usb - USB testing tools' @echo ' virtio - vhost test module' @echo ' vm - misc vm tools' + @echo ' wmi - WMI interface examples' @echo ' x86_energy_perf_policy - Intel energy policy tool' @echo '' @echo 'You can do:' @@ -57,7 +58,7 @@ acpi: FORCE cpupower: FORCE $(call descend,power/$@) -cgroup firewire hv guest spi usb virtio vm net iio gpio objtool leds: FORCE +cgroup firewire hv guest spi usb virtio vm net iio gpio objtool leds wmi: FORCE $(call descend,$@) liblockdep: FORCE @@ -92,7 +93,7 @@ kvm_stat: FORCE all: acpi cgroup cpupower gpio hv firewire liblockdep \ perf selftests spi turbostat usb \ virtio vm net x86_energy_perf_policy \ - tmon freefall iio objtool kvm_stat + tmon freefall iio objtool kvm_stat wmi acpi_install: $(call descend,power/$(@:_install=),install) @@ -100,7 +101,7 @@ acpi_install: cpupower_install: $(call descend,power/$(@:_install=),install) -cgroup_install firewire_install gpio_install hv_install iio_install perf_install spi_install usb_install virtio_install vm_install net_install objtool_install: +cgroup_install firewire_install gpio_install hv_install iio_install perf_install spi_install usb_install virtio_install vm_install net_install objtool_install wmi_install: $(call descend,$(@:_install=),install) liblockdep_install: @@ -125,7 +126,8 @@ install: acpi_install cgroup_install cpupower_install gpio_install \ hv_install firewire_install iio_install liblockdep_install \ perf_install selftests_install turbostat_install usb_install \ virtio_install vm_install net_install x86_energy_perf_policy_install \ - tmon_install freefall_install objtool_install kvm_stat_install + tmon_install freefall_install objtool_install kvm_stat_install \ + wmi_install acpi_clean: $(call descend,power/acpi,clean) @@ -133,7 +135,7 @@ acpi_clean: cpupower_clean: $(call descend,power/cpupower,clean) -cgroup_clean hv_clean firewire_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean gpio_clean objtool_clean leds_clean: +cgroup_clean hv_clean firewire_clean spi_clean usb_clean virtio_clean vm_clean wmi_clean net_clean iio_clean gpio_clean objtool_clean leds_clean: $(call descend,$(@:_clean=),clean) liblockdep_clean: @@ -171,6 +173,6 @@ clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean \ perf_clean selftests_clean turbostat_clean spi_clean usb_clean virtio_clean \ vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean \ freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \ - gpio_clean objtool_clean leds_clean + gpio_clean objtool_clean leds_clean wmi_clean .PHONY: FORCE diff --git a/tools/wmi/Makefile b/tools/wmi/Makefile new file mode 100644 index 0000000..e664f11 --- /dev/null +++ b/tools/wmi/Makefile @@ -0,0 +1,18 @@ +PREFIX ?= /usr +SBINDIR ?= sbin +INSTALL ?= install +CFLAGS += -D__EXPORTED_HEADERS__ -I../../include/uapi -I../../include +CC = $(CROSS_COMPILE)gcc + +TARGET = dell-smbios-example + +all: $(TARGET) + +%: %.c + $(CC) $(CFLAGS) $(LDFLAGS) -o $@ $< + +clean: + $(RM) $(TARGET) + +install: dell-smbios-example + $(INSTALL) -D -m 755 $(TARGET) $(DESTDIR)$(PREFIX)/$(SBINDIR)/$(TARGET) diff --git a/tools/wmi/dell-smbios-example.c b/tools/wmi/dell-smbios-example.c new file mode 100644 index 0000000..9d3bde0 --- /dev/null +++ b/tools/wmi/dell-smbios-example.c @@ -0,0 +1,210 @@ +/* + * Sample application for SMBIOS communication over WMI interface + * Performs the following: + * - Simple cmd_class/cmd_select lookup for TPM information + * - Simple query of known tokens and their values + * - Simple activation of a token + * + * Copyright (C) 2017 Dell, Inc. + * + * 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. + */ + +#include +#include +#include +#include +#include +#include + +/* if uapi header isn't installed, this might not yet exist */ +#ifndef __packed +#define __packed __attribute__((packed)) +#endif +#include + +/* It would be better to discover these using udev, but for a simple + * application they're hardcoded + */ +static const char *ioctl_devfs = "/dev/wmi/dell-smbios"; +static const char *token_sysfs = + "/sys/bus/platform/devices/dell-smbios.0/tokens"; + +static void show_buffer(struct dell_wmi_smbios_buffer *buffer) +{ + printf("Call: %x/%x [%x,%x,%x,%x]\nResults: [%8x,%8x,%8x,%8x]\n", + buffer->std.cmd_class, buffer->std.cmd_select, + buffer->std.input[0], buffer->std.input[1], + buffer->std.input[2], buffer->std.input[3], + buffer->std.output[0], buffer->std.output[1], + buffer->std.output[2], buffer->std.output[3]); +} + +static int run_wmi_smbios_cmd(struct dell_wmi_smbios_buffer *buffer) +{ + int fd; + int ret; + + fd = open(ioctl_devfs, O_NONBLOCK); + ret = ioctl(fd, DELL_WMI_SMBIOS_CMD, buffer); + close(fd); + return ret; +} + +static int find_token(__u16 token, __u16 *location, __u16 *value) +{ + char location_sysfs[60]; + char value_sysfs[57]; + char buf[4096]; + FILE *f; + int ret; + + ret = sprintf(value_sysfs, "%s/%04x_value", token_sysfs, token); + if (ret < 0) { + printf("sprintf value failed\n"); + return 2; + } + f = fopen(value_sysfs, "rb"); + if (!f) { + printf("failed to open %s\n", value_sysfs); + return 2; + } + fread(buf, 1, 4096, f); + fclose(f); + *value = (__u16) strtol(buf, NULL, 16); + + ret = sprintf(location_sysfs, "%s/%04x_location", token_sysfs, token); + if (ret < 0) { + printf("sprintf location failed\n"); + return 1; + } + f = fopen(location_sysfs, "rb"); + if (!f) { + printf("failed to open %s\n", location_sysfs); + return 2; + } + fread(buf, 1, 4096, f); + fclose(f); + *location = (__u16) strtol(buf, NULL, 16); + + if (*location) + return 0; + return 2; +} + +static int token_is_active(__u16 *location, __u16 *cmpvalue, + struct dell_wmi_smbios_buffer *buffer) +{ + int ret; + + buffer->std.cmd_class = CLASS_TOKEN_READ; + buffer->std.cmd_select = SELECT_TOKEN_STD; + buffer->std.input[0] = *location; + ret = run_wmi_smbios_cmd(buffer); + if (ret != 0 || buffer->std.output[0] != 0) + return ret; + ret = (buffer->std.output[1] == *cmpvalue); + return ret; +} + +static int query_token(__u16 token, struct dell_wmi_smbios_buffer *buffer) +{ + __u16 location; + __u16 value; + int ret; + + ret = find_token(token, &location, &value); + if (ret != 0) { + printf("unable to find token %04x\n", token); + return 1; + } + return token_is_active(&location, &value, buffer); +} + +static int activate_token(struct dell_wmi_smbios_buffer *buffer, + __u16 token) +{ + __u16 location; + __u16 value; + int ret; + + ret = find_token(token, &location, &value); + if (ret != 0) { + printf("unable to find token %04x\n", token); + return 1; + } + buffer->std.cmd_class = CLASS_TOKEN_WRITE; + buffer->std.cmd_select = SELECT_TOKEN_STD; + buffer->std.input[0] = location; + buffer->std.input[1] = 1; + ret = run_wmi_smbios_cmd(buffer); + return ret; +} + +static int query_buffer_size(__u64 *buffer_size) +{ + FILE *f; + + f = fopen(ioctl_devfs, "rb"); + if (!f) + return -EINVAL; + fread(buffer_size, sizeof(__u64), 1, f); + fclose(f); + return EXIT_SUCCESS; +} + +int main(void) +{ + struct dell_wmi_smbios_buffer *buffer; + int ret; + __u64 value = 0; + + ret = query_buffer_size(&value); + if (ret == EXIT_FAILURE || !value) { + printf("Unable to read buffer size\n"); + goto out; + } + printf("Detected required buffer size %lld\n", value); + + buffer = malloc(value); + if (buffer == NULL) { + printf("failed to alloc memory for ioctl\n"); + ret = -ENOMEM; + goto out; + } + buffer->length = value; + + /* simple SMBIOS call for looking up TPM info */ + buffer->std.cmd_class = CLASS_FLASH_INTERFACE; + buffer->std.cmd_select = SELECT_FLASH_INTERFACE; + buffer->std.input[0] = 2; + ret = run_wmi_smbios_cmd(buffer); + if (ret) { + printf("smbios ioctl failed: %d\n", ret); + ret = EXIT_FAILURE; + goto out; + } + show_buffer(buffer); + + /* query some tokens */ + ret = query_token(CAPSULE_EN_TOKEN, buffer); + printf("UEFI Capsule enabled token is: %d\n", ret); + ret = query_token(CAPSULE_DIS_TOKEN, buffer); + printf("UEFI Capsule disabled token is: %d\n", ret); + + /* activate UEFI capsule token if disabled */ + if (ret) { + printf("Enabling UEFI capsule token"); + if (activate_token(buffer, CAPSULE_EN_TOKEN)) { + printf("activate failed\n"); + ret = -1; + goto out; + } + } + ret = EXIT_SUCCESS; +out: + free(buffer); + return ret; +} -- 2.7.4