include/uapi/linux/fdreg.h
Source file repositories/reference/linux-study-clean/include/uapi/linux/fdreg.h
File Facts
- System
- Linux kernel
- Corpus path
include/uapi/linux/fdreg.h- Extension
.h- Size
- 5364 bytes
- Lines
- 141
- Domain
- Core OS
- Bucket
- Core Kernel Interface
- Inferred role
- Core OS: implementation source
- Status
- source implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
#ifndef _LINUX_FDREG_H
#define _LINUX_FDREG_H
/*
* This file contains some defines for the floppy disk controller.
* Various sources. Mostly "IBM Microcomputers: A Programmers
* Handbook", Sanches and Canton.
*/
/* 82077's auxiliary status registers A & B (R) */
#define FD_SRA 0
#define FD_SRB 1
/* Digital Output Register */
#define FD_DOR 2
/* 82077's tape drive register (R/W) */
#define FD_TDR 3
/* 82077's data rate select register (W) */
#define FD_DSR 4
/* Fd controller regs. S&C, about page 340 */
#define FD_STATUS 4
#define FD_DATA 5
/* Digital Input Register (read) */
#define FD_DIR 7
/* Diskette Control Register (write)*/
#define FD_DCR 7
/* Bits of main status register */
#define STATUS_BUSYMASK 0x0F /* drive busy mask */
#define STATUS_BUSY 0x10 /* FDC busy */
#define STATUS_DMA 0x20 /* 0- DMA mode */
#define STATUS_DIR 0x40 /* 0- cpu->fdc */
#define STATUS_READY 0x80 /* Data reg ready */
/* Bits of FD_ST0 */
#define ST0_DS 0x03 /* drive select mask */
#define ST0_HA 0x04 /* Head (Address) */
#define ST0_NR 0x08 /* Not Ready */
#define ST0_ECE 0x10 /* Equipment check error */
#define ST0_SE 0x20 /* Seek end */
#define ST0_INTR 0xC0 /* Interrupt code mask */
/* Bits of FD_ST1 */
#define ST1_MAM 0x01 /* Missing Address Mark */
#define ST1_WP 0x02 /* Write Protect */
#define ST1_ND 0x04 /* No Data - unreadable */
#define ST1_OR 0x10 /* OverRun */
#define ST1_CRC 0x20 /* CRC error in data or addr */
#define ST1_EOC 0x80 /* End Of Cylinder */
/* Bits of FD_ST2 */
#define ST2_MAM 0x01 /* Missing Address Mark (again) */
#define ST2_BC 0x02 /* Bad Cylinder */
#define ST2_SNS 0x04 /* Scan Not Satisfied */
#define ST2_SEH 0x08 /* Scan Equal Hit */
#define ST2_WC 0x10 /* Wrong Cylinder */
#define ST2_CRC 0x20 /* CRC error in data field */
#define ST2_CM 0x40 /* Control Mark = deleted */
/* Bits of FD_ST3 */
#define ST3_HA 0x04 /* Head (Address) */
#define ST3_DS 0x08 /* drive is double-sided */
#define ST3_TZ 0x10 /* Track Zero signal (1=track 0) */
#define ST3_RY 0x20 /* drive is ready */
#define ST3_WP 0x40 /* Write Protect */
#define ST3_FT 0x80 /* Drive Fault */
/* Values for FD_COMMAND */
#define FD_RECALIBRATE 0x07 /* move to track 0 */
#define FD_SEEK 0x0F /* seek track */
#define FD_READ 0xE6 /* read with MT, MFM, SKip deleted */
#define FD_WRITE 0xC5 /* write with MT, MFM */
#define FD_SENSEI 0x08 /* Sense Interrupt Status */
#define FD_SPECIFY 0x03 /* specify HUT etc */
#define FD_FORMAT 0x4D /* format one track */
#define FD_VERSION 0x10 /* get version code */
#define FD_CONFIGURE 0x13 /* configure FIFO operation */
#define FD_PERPENDICULAR 0x12 /* perpendicular r/w mode */
#define FD_GETSTATUS 0x04 /* read ST3 */
#define FD_DUMPREGS 0x0E /* dump the contents of the fdc regs */
#define FD_READID 0xEA /* prints the header of a sector */
#define FD_UNLOCK 0x14 /* Fifo config unlock */
#define FD_LOCK 0x94 /* Fifo config lock */
#define FD_RSEEK_OUT 0x8f /* seek out (i.e. to lower tracks) */
#define FD_RSEEK_IN 0xcf /* seek in (i.e. to higher tracks) */
Annotation
- Atlas domain: Core OS / Core Kernel Interface.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.