diff options
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/firmware/efi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/firmware/efi/apple-properties.c | 248 |
3 files changed, 262 insertions, 0 deletions
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 893fda48fcdd..2e78b0b96d74 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -129,6 +129,19 @@ config EFI_TEST Say Y here to enable the runtime services support via /dev/efi_test. If unsure, say N. +config APPLE_PROPERTIES + bool "Apple Device Properties" + depends on EFI_STUB && X86 + select EFI_DEV_PATH_PARSER + select UCS2_STRING + help + Retrieve properties from EFI on Apple Macs and assign them to + devices, allowing for improved support of Apple hardware. + Properties that would otherwise be missing include the + Thunderbolt Device ROM and GPU configuration data. + + If unsure, say Y if you have a Mac. Otherwise N. + endmenu config UEFI_CPER diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 3e91ae31f9d1..ad67342313ed 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o obj-$(CONFIG_EFI_TEST) += test/ obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o +obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o obj-$(CONFIG_ARM) += $(arm-obj-y) diff --git a/drivers/firmware/efi/apple-properties.c b/drivers/firmware/efi/apple-properties.c new file mode 100644 index 000000000000..c473f4c5ca34 --- /dev/null +++ b/drivers/firmware/efi/apple-properties.c @@ -0,0 +1,248 @@ +/* + * apple-properties.c - EFI device properties on Macs + * Copyright (C) 2016 Lukas Wunner <lukas@wunner.de> + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) "apple-properties: " fmt + +#include <linux/bootmem.h> +#include <linux/dmi.h> +#include <linux/efi.h> +#include <linux/property.h> +#include <linux/slab.h> +#include <linux/ucs2_string.h> +#include <asm/setup.h> + +static bool dump_properties __initdata; + +static int __init dump_properties_enable(char *arg) +{ + dump_properties = true; + return 0; +} + +__setup("dump_apple_properties", dump_properties_enable); + +struct dev_header { + u32 len; + u32 prop_count; + struct efi_dev_path path[0]; + /* + * followed by key/value pairs, each key and value preceded by u32 len, + * len includes itself, value may be empty (in which case its len is 4) + */ +}; + +struct properties_header { + u32 len; + u32 version; + u32 dev_count; + struct dev_header dev_header[0]; +}; + +static u8 one __initdata = 1; + +static void __init unmarshal_key_value_pairs(struct dev_header *dev_header, + struct device *dev, void *ptr, + struct property_entry entry[]) +{ + int i; + + for (i = 0; i < dev_header->prop_count; i++) { + int remaining = dev_header->len - (ptr - (void *)dev_header); + u32 key_len, val_len; + char *key; + + if (sizeof(key_len) > remaining) + break; + + key_len = *(typeof(key_len) *)ptr; + if (key_len + sizeof(val_len) > remaining || + key_len < sizeof(key_len) + sizeof(efi_char16_t) || + *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) { + dev_err(dev, "invalid property name len at %#zx\n", + ptr - (void *)dev_header); + break; + } + + val_len = *(typeof(val_len) *)(ptr + key_len); + if (key_len + val_len > remaining || + val_len < sizeof(val_len)) { + dev_err(dev, "invalid property val len at %#zx\n", + ptr - (void *)dev_header + key_len); + break; + } + + /* 4 bytes to accommodate UTF-8 code points + null byte */ + key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL); + if (!key) { + dev_err(dev, "cannot allocate property name\n"); + break; + } + ucs2_as_utf8(key, ptr + sizeof(key_len), + key_len - sizeof(key_len)); + + entry[i].name = key; + entry[i].is_array = true; + entry[i].length = val_len - sizeof(val_len); + entry[i].pointer.raw_data = ptr + key_len + sizeof(val_len); + if (!entry[i].length) { + /* driver core doesn't accept empty properties */ + entry[i].length = 1; + entry[i].pointer.raw_data = &one; + } + + if (dump_properties) { + dev_info(dev, "property: %s\n", entry[i].name); + print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, entry[i].pointer.raw_data, + entry[i].length, true); + } + + ptr += key_len + val_len; + } + + if (i != dev_header->prop_count) { + dev_err(dev, "got %d device properties, expected %u\n", i, + dev_header->prop_count); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, dev_header, dev_header->len, true); + return; + } + + dev_info(dev, "assigning %d device properties\n", i); +} + +static int __init unmarshal_devices(struct properties_header *properties) +{ + size_t offset = offsetof(struct properties_header, dev_header[0]); + + while (offset + sizeof(struct dev_header) < properties->len) { + struct dev_header *dev_header = (void *)properties + offset; + struct property_entry *entry = NULL; + struct device *dev; + size_t len; + int ret, i; + void *ptr; + + if (offset + dev_header->len > properties->len || + dev_header->len <= sizeof(*dev_header)) { + pr_err("invalid len in dev_header at %#zx\n", offset); + return -EINVAL; + } + + ptr = dev_header->path; + len = dev_header->len - sizeof(*dev_header); + + dev = efi_get_device_by_path((struct efi_dev_path **)&ptr, &len); + if (IS_ERR(dev)) { + pr_err("device path parse error %ld at %#zx:\n", + PTR_ERR(dev), ptr - (void *)dev_header); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, dev_header, dev_header->len, true); + dev = NULL; + goto skip_device; + } + + entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry), + GFP_KERNEL); + if (!entry) { + dev_err(dev, "cannot allocate properties\n"); + goto skip_device; + } + + unmarshal_key_value_pairs(dev_header, dev, ptr, entry); + if (!entry[0].name) + goto skip_device; + + ret = device_add_properties(dev, entry); /* makes deep copy */ + if (ret) + dev_err(dev, "error %d assigning properties\n", ret); + + for (i = 0; entry[i].name; i++) + kfree(entry[i].name); + +skip_device: + kfree(entry); + put_device(dev); + offset += dev_header->len; + } + + return 0; +} + +static int __init map_properties(void) +{ + struct properties_header *properties; + struct setup_data *data; + u32 data_len; + u64 pa_data; + int ret; + + if (!dmi_match(DMI_SYS_VENDOR, "Apple Inc.") && + !dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc.")) + return 0; + + pa_data = boot_params.hdr.setup_data; + while (pa_data) { + data = ioremap(pa_data, sizeof(*data)); + if (!data) { + pr_err("cannot map setup_data header\n"); + return -ENOMEM; + } + + if (data->type != SETUP_APPLE_PROPERTIES) { + pa_data = data->next; + iounmap(data); + continue; + } + + data_len = data->len; + iounmap(data); + + data = ioremap(pa_data, sizeof(*data) + data_len); + if (!data) { + pr_err("cannot map setup_data payload\n"); + return -ENOMEM; + } + + properties = (struct properties_header *)data->data; + if (properties->version != 1) { + pr_err("unsupported version:\n"); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, properties, data_len, true); + ret = -ENOTSUPP; + } else if (properties->len != data_len) { + pr_err("length mismatch, expected %u\n", data_len); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, properties, data_len, true); + ret = -EINVAL; + } else + ret = unmarshal_devices(properties); + + /* + * Can only free the setup_data payload but not its header + * to avoid breaking the chain of ->next pointers. + */ + data->len = 0; + iounmap(data); + free_bootmem_late(pa_data + sizeof(*data), data_len); + + return ret; + } + return 0; +} + +fs_initcall(map_properties); |