From 7df2bda626cf887c969d8b434c8f15caec432ec3 Mon Sep 17 00:00:00 2001 From: Matt Domsch Date: Wed, 9 Oct 2002 05:16:19 -0500 Subject: EDD: x86 BIOS Enhanced Disk Drive support The major changes implemented in this patch: arch/i386/boot/setup.S - int13 real mode calls store results in empty_zero_page arch/i386/kernel/setup.c - copy results from empty_zero_page to local storage arch/i386/kernel/edd.c - module exports results via driverfs x86 systems suffer from a disconnect between what BIOS believes is the boot disk, and what Linux thinks BIOS thinks is the boot disk. This manifests itself in multi-disk systems - it's quite possible to install a distribution, only to fail on reboot - the disk installed to is not the disk BIOS is booting from. Dell restricts our possible standard factory installed Linux offerings to "disks on no more than one controller" to avoid this problem, but mechanisms now exist to solve it and allow such configurations. BIOS Enhanced Disk Device Services (EDD) 3.0 provides the ability for disk adapter BIOSs to tell the OS what it believes is the boot disk. While this isn't widely implemented in BIOSs yet, it's time that Linux received support to be ready as BIOSs with this feature do become available. At a minimum, LSI MegaRAID cards support this today. EDD works by providing the bus (PCI, PCI-X, ISA, InfiniBand, PCI Express, or HyperTransport) location (e.g. PCI 02:01.0) and interface (ATAPI, ATA, SCSI, USB, 1394, FibreChannel, I2O, RAID, SATA) location (e.g. SCSI ID 5 LUN 0) information for each BIOS int13 device. The patch below creates CONFIG_EDD, that when defined, makes the BIOS int13 calls to retrieve and store this information. The data is copied to a safe place in setup.c, and exported via driverfs. Here's a sample driverfs tree with two BIOS int13 devices - dev 80 has incorrect PCI bus information, thus no symlinks are made, but as much info as possible is presented. Dev 81 has correct PCI and SCSI information, thus symlinks are made to the actual disc device. /driverfs |-- bios | |-- int13_dev80 | | |-- extensions | | |-- host_bus | | |-- info_flags | | |-- interface | | |-- raw_data | | |-- sectors | | `-- version | `-- int13_dev81 | |-- extensions | |-- host_bus | |-- info_flags | |-- interface | |-- pci_dev -> ../../root/pci2/02:0c.0/03:00.0/04:00.0 | |-- raw_data | |-- disc -> ../../root/pci2/02:0c.0/03:00.0/04:00.0/scsi4/4:0:0:0 | |-- sectors | `-- version |-- bus | |-- scsi | | |-- devices | | | |-- 4:0:0:0 -> ../../../root/pci2/02:0c.0/03:00.0/04:00.0/scsi4/4:0:0:0 | | `-- drivers | | `-- sd `-- root |-- pci2 | |-- 02:0c.0 | | |-- 03:00.0 | | | |-- 04:00.0 | | | | |-- irq | | | | |-- name | | | | |-- power | | | | |-- resource | | | | `-- scsi4 | | | | |-- 4:0:0:0 | | | | | |-- 4:0:0:0::p1 | | | | | | |-- kdev | | | | | | |-- name | | | | | | |-- power | | | | | | `-- type | | | | | |-- 4:0:0:0:disc | | | | | | |-- kdev | | | | | | |-- name | | | | | | |-- power | | | | | | `-- type | | | | | |-- name | | | | | |-- power | | | | | `-- type (Yes, the 'bios' top-level directory isn't the right place, and Patrick has promised to make something there in the future, at which point this can be moved.) The 'raw_data' file contains the full set of information returned by BIOS with extra error reporting. This exists for vendor BIOS debugging purposes. The 'host-bus' file contains the PCI (or ISA, HyperTransport, ...) identifying information, as BIOS knows it. The 'interface' file contains the SCSI (or IDE, USB, ...) identifying information, as BIOS knows it. The 'extensions' file lists the BIOS EDD extensions per spec. The 'info_flags' file lists the BIOS EDD device information flags per spec. The 'sectors' file reports the number of sectors BIOS believes this device has. The 'version' file lists the EDD version. To have device path information, this must be 0x30 or above. Earlier EDD versions exist without the device path - as much information as is available is presented. At most 6 BIOS devices are reported, as that fills the space that's left in the empty_zero_page. In general you only care about device 80h, though for software RAID1 knowing what 81h is might be useful also. Known issues: - module unload leaves a directory around. Seems related to creating symlinks in that directory. Seen on kernel 2.5.41. - refcounting of struct device objects could be improved. TODO: - Add IDE and USB disk device support - when driverfs model of discs and partitions changes, update symlink accordingly. - Get symlink creator helper functions exported from drivers/base instead of duplicating them here. - move edd.[ch] to better locations if/when one is decided I'd also like to acknowledge the help and comments received from Greg KH and Patrick Mochel. This isn't something driverfs was originally conceived to handle, their assistance has been invaluable. Please pull from: BK: http://mdomsch.bkbits.net/linux-2.5-edd-tolinus Patch (against 2.5.41+BK-current): http://domsch.com/linux/edd30/edd-driverfs-6.patch http://domsch.com/linux/edd30/edd-driverfs-6.patch.sign Thanks, Matt -- Matt Domsch Sr. Software Engineer, Lead Engineer, Architect Dell Linux Solutions www.dell.com/linux Linux on Dell mailing lists @ http://lists.us.dell.com --- include/asm-i386/edd.h | 168 +++++++++++++++++++++++++++++++++++++++++++++++ include/asm-i386/setup.h | 2 + 2 files changed, 170 insertions(+) create mode 100644 include/asm-i386/edd.h (limited to 'include') diff --git a/include/asm-i386/edd.h b/include/asm-i386/edd.h new file mode 100644 index 000000000000..d59cf602c10d --- /dev/null +++ b/include/asm-i386/edd.h @@ -0,0 +1,168 @@ +/* + * linux/include/asm-i386/edd.h + * Copyright (C) 2002 Dell Computer Corporation + * by Matt Domsch + * + * structures and definitions for the int 13h, ax={41,48}h + * BIOS Enhanced Disk Drive Services + * This is based on the T13 group document D1572 Revision 0 (August 14 2002) + * available at http://www.t13.org/docs2002/d1572r0.pdf. It is + * very similar to D1484 Revision 3 http://www.t13.org/docs2002/d1484r3.pdf + * + * In a nutshell, arch/i386/boot/setup.S populates a scratch table + * in the empty_zero_block that contains a list of BIOS-enumerated + * boot devices. + * In arch/i386/kernel/setup.c, this information is + * transferred into the edd structure, and in arch/i386/kernel/edd.c, that + * information is used to identify BIOS boot disk. The code in setup.S + * is very sensitive to the size of these structures. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License v2.0 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. + * + */ +#ifndef _ASM_I386_EDD_H +#define _ASM_I386_EDD_H + +#define EDDNR 0x1e9 /* addr of number of edd_info structs at EDDBUF + in empty_zero_block - treat this as 1 byte */ +#define EDDBUF 0x600 /* addr of edd_info structs in empty_zero_block */ +#define EDDMAXNR 6 /* number of edd_info structs starting at EDDBUF */ +#define EDDEXTSIZE 4 /* change these if you muck with the structures */ +#define EDDPARMSIZE 74 + +#ifndef __ASSEMBLY__ + +#define EDD_EXT_FIXED_DISK_ACCESS (1 << 0) +#define EDD_EXT_DEVICE_LOCKING_AND_EJECTING (1 << 1) +#define EDD_EXT_ENHANCED_DISK_DRIVE_SUPPORT (1 << 2) +#define EDD_EXT_64BIT_EXTENSIONS (1 << 3) + +#define EDD_INFO_DMA_BOUNDRY_ERROR_TRANSPARENT (1 << 0) +#define EDD_INFO_GEOMETRY_VALID (1 << 1) +#define EDD_INFO_REMOVABLE (1 << 2) +#define EDD_INFO_WRITE_VERIFY (1 << 3) +#define EDD_INFO_MEDIA_CHANGE_NOTIFICATION (1 << 4) +#define EDD_INFO_LOCKABLE (1 << 5) +#define EDD_INFO_NO_MEDIA_PRESENT (1 << 6) +#define EDD_INFO_USE_INT13_FN50 (1 << 7) + +struct edd_device_params { + u16 length; + u16 info_flags; + u32 num_default_cylinders; + u32 num_default_heads; + u32 sectors_per_track; + u64 number_of_sectors; + u16 bytes_per_sector; + u32 dpte_ptr; /* 0xFFFFFFFF for our purposes */ + u16 key; /* = 0xBEDD */ + u8 device_path_info_length; /* = 44 */ + u8 reserved2; + u16 reserved3; + u8 host_bus_type[4]; + u8 interface_type[8]; + union { + struct { + u16 base_address; + u16 reserved1; + u32 reserved2; + } __attribute__ ((packed)) isa; + struct { + u8 bus; + u8 slot; + u8 function; + u8 channel; + u32 reserved; + } __attribute__ ((packed)) pci; + /* pcix is same as pci */ + struct { + u64 reserved; + } __attribute__ ((packed)) ibnd; + struct { + u64 reserved; + } __attribute__ ((packed)) xprs; + struct { + u64 reserved; + } __attribute__ ((packed)) htpt; + struct { + u64 reserved; + } __attribute__ ((packed)) unknown; + } interface_path; + union { + struct { + u8 device; + u8 reserved1; + u16 reserved2; + u32 reserved3; + u64 reserved4; + } __attribute__ ((packed)) ata; + struct { + u8 device; + u8 lun; + u8 reserved1; + u8 reserved2; + u32 reserved3; + u64 reserved4; + } __attribute__ ((packed)) atapi; + struct { + u16 id; + u64 lun; + u16 reserved1; + u32 reserved2; + } __attribute__ ((packed)) scsi; + struct { + u64 serial_number; + u64 reserved; + } __attribute__ ((packed)) usb; + struct { + u64 eui; + u64 reserved; + } __attribute__ ((packed)) i1394; + struct { + u64 wwid; + u64 lun; + } __attribute__ ((packed)) fibre; + struct { + u64 identity_tag; + u64 reserved; + } __attribute__ ((packed)) i2o; + struct { + u32 array_number; + u32 reserved1; + u64 reserved2; + } __attribute((packed)) raid; + struct { + u8 device; + u8 reserved1; + u16 reserved2; + u32 reserved3; + u64 reserved4; + } __attribute__ ((packed)) sata; + struct { + u64 reserved1; + u64 reserved2; + } __attribute__ ((packed)) unknown; + } device_path; + u8 reserved4; + u8 checksum; +} __attribute__ ((packed)); + +struct edd_info { + u8 device; + u8 version; + u16 interface_support; + struct edd_device_params params; +} __attribute__ ((packed)); + +extern struct edd_info edd[EDDNR]; +extern unsigned char eddnr; +#endif /*!__ASSEMBLY__ */ + +#endif /* _ASM_I386_EDD_H */ diff --git a/include/asm-i386/setup.h b/include/asm-i386/setup.h index 01d981332fea..a89487b409b8 100644 --- a/include/asm-i386/setup.h +++ b/include/asm-i386/setup.h @@ -37,6 +37,8 @@ #define KERNEL_START (*(unsigned long *) (PARAM+0x214)) #define INITRD_START (*(unsigned long *) (PARAM+0x218)) #define INITRD_SIZE (*(unsigned long *) (PARAM+0x21c)) +#define EDD_NR (*(unsigned char *) (PARAM+EDDNR)) +#define EDD_BUF ((struct edd_info *) (PARAM+EDDBUF)) #define COMMAND_LINE ((char *) (PARAM+2048)) #define COMMAND_LINE_SIZE 256 -- cgit v1.2.3