/* * Copyright (C) 1991, 1992 Linus Torvalds * * This is the low-level hd interrupt support. It traverses the * request-list, using interrupts to jump between functions. As * all the functions are called within interrupts, we may not * sleep. Special care is recommended. * * modified by Drew Eckhardt to check nr of hd's from the CMOS. * * Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug * in the early extended-partition checks and added DM partitions * * IRQ-unmask, drive-id, multiple-mode, support for ">16 heads", * and general streamlining by Mark Lord. * * Removed 99% of above. Use Mark's ide driver for those options. * This is now a lightweight ST-506 driver. (Paul Gortmaker) * * Modified 1995 Russell King for ARM processor. * * Bugfix: max_sectors must be <= 255 or the wheels tend to come * off in a hurry once you queue things up - Paul G. 02/2001 */ /* Uncomment the following if you want verbose error reports. */ /* #define VERBOSE_ERRORS */ #include <linux/blkdev.h> #include <linux/errno.h> #include <linux/signal.h> #include <linux/interrupt.h> #include <linux/timer.h> #include <linux/fs.h> #include <linux/kernel.h> #include <linux/genhd.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/ioport.h> #include <linux/init.h> #include <linux/blkpg.h> #include <linux/ata.h> #include <linux/hdreg.h> #define REALLY_SLOW_IO #include <asm/system.h> #include <asm/io.h> #include <asm/uaccess.h> #ifdef __arm__ #undef HD_IRQ #endif #include <asm/irq.h> #ifdef __arm__ #define HD_IRQ IRQ_HARDDISK #endif /* Hd controller regster ports */ #define HD_DATA 0x1f0 /* _CTL when writing */ #define HD_ERROR 0x1f1 /* see err-bits */ #define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */ #define HD_SECTOR 0x1f3 /* starting sector */ #define HD_LCYL 0x1f4 /* starting cylinder */ #define HD_HCYL 0x1f5 /* high byte of starting cyl */ #define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */ #define HD_STATUS 0x1f7 /* see status-bits */ #define HD_FEATURE HD_ERROR /* same io address, read=error, write=feature */ #define HD_PRECOMP HD_FEATURE /* obsolete use of this port - predates IDE */ #define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */ #define HD_CMD 0x3f6 /* used for resets */ #define HD_ALTSTATUS 0x3f6 /* same as HD_STATUS but doesn't clear irq */ /* Bits of HD_STATUS */ #define ERR_STAT 0x01 #define INDEX_STAT 0x02 #define ECC_STAT 0x04 /* Corrected error */ #define DRQ_STAT 0x08 #define SEEK_STAT 0x10 #define SERVICE_STAT SEEK_STAT #define WRERR_STAT 0x20 #define READY_STAT 0x40 #define BUSY_STAT 0x80 /* Bits for HD_ERROR */ #define MARK_ERR 0x01 /* Bad address mark */ #define TRK0_ERR 0x02 /* couldn't find track 0 */ #define ABRT_ERR 0x04 /* Command aborted */ #define MCR_ERR 0x08 /* media change request */ #define ID_ERR 0x10 /* ID field not found */ #define MC_ERR 0x20 /* media changed */ #define ECC_ERR 0x40 /* Uncorrectable ECC error */ #define BBD_ERR 0x80 /* pre-EIDE meaning: block marked bad */ #define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */ static DEFINE_SPINLOCK(hd_lock); static struct request_queue *hd_queue; #define MAJOR_NR HD_MAJOR #define QUEUE (hd_queue) #define CURRENT elv_next_request(hd_queue) #define TIMEOUT_VALUE (6*HZ) #define HD_DELAY 0 #define MAX_ERRORS 16 /* Max read/write errors/sector */ #define RESET_FREQ 8 /* Reset controller every 8th retry */ #define RECAL_FREQ 4 /* Recalibrate every 4th retry */ #define MAX_HD 2 #define STAT_OK (READY_STAT|SEEK_STAT) #define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK) static void recal_intr(void); static void bad_rw_intr(void); static int reset; static int hd_error; /* * This struct defines the HD's and their types. */ struct hd_i_struct { unsigned int head, sect, cyl, wpcom, lzone, ctl; int unit; int recalibrate; int special_op; }; #ifdef HD_TYPE static struct hd_i_struct hd_info[] = { HD_TYPE }; static int NR_HD = ARRAY_SIZE(hd_info); #else static struct hd_i_struct hd_info[MAX_HD]; static int NR_HD; #endif static struct gendisk *hd_gendisk[MAX_HD]; static struct timer_list device_timer; #define TIMEOUT_VALUE (6*HZ) #define SET_TIMER \ do { \ mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \ } while (0) static void (*do_hd)(void) = NULL; #define SET_HANDLER(x) \ if ((do_hd = (x)) != NULL) \ SET_TIMER; \ else \ del_timer(&device_timer); #if (HD_DELAY > 0) #include <asm/i8253.h> unsigned long last_req; unsigned long read_timer(void) { unsigned long t, flags; int i; spin_lock_irqsave(&i8253_lock, flags); t = jiffies * 11932; outb_p(0, 0x43); i = inb_p(0x40); i |= inb(0x40) << 8; spin_unlock_irqrestore(&i8253_lock, flags); return(t - i); } #endif static void __init hd_setup(char *str, int *ints) { int hdind = 0; if (ints[0] != 3) return; if (hd_info[0].head != 0) hdind = 1; hd_info[hdind].head = ints[2]; hd_info[hdind].sect = ints[3]; hd_info[hdind].cyl = ints[1]; hd_info[hdind].wpcom = 0; hd_info[hdind].lzone = ints[1]; hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0); NR_HD = hdind+1; } static void dump_status(const char *msg, unsigned int stat) { char *name = "hd?"; if (CURRENT) name = CURRENT->rq_disk->disk_name; #ifdef VERBOSE_ERRORS printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff); if (stat & BUSY_STAT) printk("Busy "); if (stat & READY_STAT) printk("DriveReady "); if (stat & WRERR_STAT) printk("WriteFault "); if (stat & SEEK_STAT) printk("SeekComplete "); if (stat & DRQ_STAT) printk("DataRequest "); if (stat & ECC_STAT) printk("CorrectedError "); if (stat & INDEX_STAT) printk("Index "); if (stat & ERR_STAT) printk("Error "); printk("}\n"); if ((stat & ERR_STAT) == 0) { hd_error = 0; } else { hd_error = inb(HD_ERROR); printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff); if (hd_error & BBD_ERR) printk("BadSector "); if (hd_error & ECC_ERR) printk("UncorrectableError "); if (hd_error & ID_ERR) printk("SectorIdNotFound "); if (hd_error & ABRT_ERR) printk("DriveStatusError "); if (hd_error & TRK0_ERR) printk("TrackZeroNotFound "); if (hd_error & MARK_ERR) printk("AddrMarkNotFound "); printk("}"); if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) { printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL), inb(HD_CURRENT) & 0xf, inb(HD_SECTOR)); if (CURRENT) printk(", sector=%ld", CURRENT->sector); } printk("\n"); } #else printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff); if ((stat & ERR_STAT) == 0) { hd_error = 0; } else { hd_error = inb(HD_ERROR); printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff); } #endif } static void check_status(void) { int i = inb_p(HD_STATUS); if (!OK_STATUS(i)) { dump_status("check_status", i); bad_rw_intr(); } } static int controller_busy(void) { int retries = 100000; unsigned char status; do { status = inb_p(HD_STATUS); } while ((status & BUSY_STAT) && --retries); return status; } static int status_ok(void) { unsigned char status = inb_p(HD_STATUS); if (status & BUSY_STAT) return 1; /* Ancient, but does it make sense??? */ if (status & WRERR_STAT) return 0; if (!(status & READY_STAT)) return 0; if (!(status & SEEK_STAT)) return 0; return 1; } static int controller_ready(unsigned int drive, unsigned int head) { int retry = 100; do { if (controller_busy() & BUSY_STAT) return 0; outb_p(0xA0 | (drive<<4) | head, HD_CURRENT); if (status_ok()) return 1; } while (--retry); return 0; } static void hd_out(struct hd_i_struct *disk, unsigned int nsect, unsigned int sect, unsigned int head, unsigned int cyl, unsigned int cmd, void (*intr_addr)(void)) { unsigned short port; #if (HD_DELAY > 0) while (read_timer() - last_req < HD_DELAY) /* nothing */; #endif if (reset) return; if (!controller_ready(disk->unit, head)) { reset = 1; return; } SET_HANDLER(intr_addr); outb_p(disk->ctl, HD_CMD); port = HD_DATA; outb_p(disk->wpcom >> 2, ++port); outb_p(nsect, ++port); outb_p(sect, ++port); outb_p(cyl, ++port); outb_p(cyl >> 8, ++port); outb_p(0xA0 | (disk->unit << 4) | head, ++port); outb_p(cmd, ++port); } static void hd_request (void); static int drive_busy(void) { unsigned int i; unsigned char c; for (i = 0; i < 500000 ; i++) { c = inb_p(HD_STATUS); if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK) return 0; } dump_status("reset timed out", c); return 1; } static void reset_controller(void) { int i; outb_p(4, HD_CMD); for (i = 0; i < 1000; i++) barrier(); outb_p(hd_info[0].ctl & 0x0f, HD_CMD); for (i = 0; i < 1000; i++) barrier(); if (drive_busy()) printk("hd: controller still busy\n"); else if ((hd_error = inb(HD_ERROR)) != 1) printk("hd: controller reset failed: %02x\n", hd_error); } static void reset_hd(void) { static int i; repeat: if (reset) { reset = 0; i = -1; reset_controller(); } else { check_status(); if (reset) goto repeat; } if (++i < NR_HD) { struct hd_i_struct *disk = &hd_info[i]; disk->special_op = disk->recalibrate = 1; hd_out(disk, disk->sect, disk->sect, disk->head-1, disk->cyl, ATA_CMD_INIT_DEV_PARAMS, &reset_hd); if (reset) goto repeat; } else hd_request(); } /* * Ok, don't know what to do with the unexpected interrupts: on some machines * doing a reset and a retry seems to result in an eternal loop. Right now I * ignore it, and just set the timeout. * * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the * drive enters "idle", "standby", or "sleep" mode, so if the status looks * "good", we just ignore the interrupt completely. */ static void unexpected_hd_interrupt(void) { unsigned int stat = inb_p(HD_STATUS); if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) { dump_status("unexpected interrupt", stat); SET_TIMER; } } /* * bad_rw_intr() now tries to be a bit smarter and does things * according to the error returned by the controller. * -Mika Liljeberg (liljeber@cs.Helsinki.FI) */ static void bad_rw_intr(void) { struct request *req = CURRENT; if (req != NULL) { struct hd_i_struct *disk = req->rq_disk->private_data; if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) { end_request(req, 0); disk->special_op = disk->recalibrate = 1; } else if (req->errors % RESET_FREQ == 0) reset = 1; else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0) disk->special_op = disk->recalibrate = 1; /* Otherwise just retry */ } } static inline int wait_DRQ(void) { int retries; int stat; for (retries = 0; retries < 100000; retries++) { stat = inb_p(HD_STATUS); if (stat & DRQ_STAT) return 0; } dump_status("wait_DRQ", stat); return -1; } static void read_intr(void) { struct request *req; int i, retries = 100000; do { i = (unsigned) inb_p(HD_STATUS); if (i & BUSY_STAT) continue; if (!OK_STATUS(i)) break; if (i & DRQ_STAT) goto ok_to_read; } while (--retries > 0); dump_status("read_intr", i); bad_rw_intr(); hd_request(); return; ok_to_read: req = CURRENT; insw(HD_DATA, req->buffer, 256); req->sector++; req->buffer += 512; req->errors = 0; i = --req->nr_sectors; --req->current_nr_sectors; #ifdef DEBUG printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n", req->rq_disk->disk_name, req->sector, req->nr_sectors, req->buffer+512); #endif if (req->current_nr_sectors <= 0) end_request(req, 1); if (i > 0) { SET_HANDLER(&read_intr); return; } (void) inb_p(HD_STATUS); #if (HD_DELAY > 0) last_req = read_timer(); #endif if (elv_next_request(QUEUE)) hd_request(); return; } static void write_intr(void) { struct request *req = CURRENT; int i; int retries = 100000; do { i = (unsigned) inb_p(HD_STATUS); if (i & BUSY_STAT) continue; if (!OK_STATUS(i)) break; if ((req->nr_sectors <= 1) || (i & DRQ_STAT)) goto ok_to_write; } while (--retries > 0); dump_status("write_intr", i); bad_rw_intr(); hd_request(); return; ok_to_write: req->sector++; i = --req->nr_sectors; --req->current_nr_sectors; req->buffer += 512; if (!i || (req->bio && req->current_nr_sectors <= 0)) end_request(req, 1); if (i > 0) { SET_HANDLER(&write_intr); outsw(HD_DATA, req->buffer, 256); local_irq_enable(); } else { #if (HD_DELAY > 0) last_req = read_timer(); #endif hd_request(); } return; } static void recal_intr(void) { check_status(); #if (HD_DELAY > 0) last_req = read_timer(); #endif hd_request(); } /* * This is another of the error-routines I don't know what to do with. The * best idea seems to just set reset, and start all over again. */ static void hd_times_out(unsigned long dummy) { char *name; do_hd = NULL; if (!CURRENT) return; disable_irq(HD_IRQ); local_irq_enable(); reset = 1; name = CURRENT->rq_disk->disk_name; printk("%s: timeout\n", name); if (++CURRENT->errors >= MAX_ERRORS) { #ifdef DEBUG printk("%s: too many errors\n", name); #endif end_request(CURRENT, 0); } local_irq_disable(); hd_request(); enable_irq(HD_IRQ); } static int do_special_op(struct hd_i_struct *disk, struct request *req) { if (disk->recalibrate) { disk->recalibrate = 0; hd_out(disk, disk->sect, 0, 0, 0, ATA_CMD_RESTORE, &recal_intr); return reset; } if (disk->head > 16) { printk("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name); end_request(req, 0); } disk->special_op = 0; return 1; } /* * The driver enables interrupts as much as possible. In order to do this, * (a) the device-interrupt is disabled before entering hd_request(), * and (b) the timeout-interrupt is disabled before the sti(). * * Interrupts are still masked (by default) whenever we are exchanging * data/cmds with a drive, because some drives seem to have very poor * tolerance for latency during I/O. The IDE driver has support to unmask * interrupts for non-broken hardware, so use that driver if required. */ static void hd_request(void) { unsigned int block, nsect, sec, track, head, cyl; struct hd_i_struct *disk; struct request *req; if (do_hd) return; repeat: del_timer(&device_timer); local_irq_enable(); req = CURRENT; if (!req) { do_hd = NULL; return; } if (reset) { local_irq_disable(); reset_hd(); return; } disk = req->rq_disk->private_data; block = req->sector; nsect = req->nr_sectors; if (block >= get_capacity(req->rq_disk) || ((block+nsect) > get_capacity(req->rq_disk))) { printk("%s: bad access: block=%d, count=%d\n", req->rq_disk->disk_name, block, nsect); end_request(req, 0); goto repeat; } if (disk->special_op) { if (do_special_op(disk, req)) goto repeat; return; } sec = block % disk->sect + 1; track = block / disk->sect; head = track % disk->head; cyl = track / disk->head; #ifdef DEBUG printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n", req->rq_disk->disk_name, req_data_dir(req) == READ ? "read" : "writ", cyl, head, sec, nsect, req->buffer); #endif if (blk_fs_request(req)) { switch (rq_data_dir(req)) { case READ: hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_READ, &read_intr); if (reset) goto repeat; break; case WRITE: hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_WRITE, &write_intr); if (reset) goto repeat; if (wait_DRQ()) { bad_rw_intr(); goto repeat; } outsw(HD_DATA, req->buffer, 256); break; default: printk("unknown hd-command\n"); end_request(req, 0); break; } } } static void do_hd_request(struct request_queue *q) { disable_irq(HD_IRQ); hd_request(); enable_irq(HD_IRQ); } static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo) { struct hd_i_struct *disk = bdev->bd_disk->private_data; geo->heads = disk->head; geo->sectors = disk->sect; geo->cylinders = disk->cyl; return 0; } /* * Releasing a block device means we sync() it, so that it can safely * be forgotten about... */ static irqreturn_t hd_interrupt(int irq, void *dev_id) { void (*handler)(void) = do_hd; do_hd = NULL; del_timer(&device_timer); if (!handler) handler = unexpected_hd_interrupt; handler(); local_irq_enable(); return IRQ_HANDLED; } static struct block_device_operations hd_fops = { .getgeo = hd_getgeo, }; /* * This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags * means we run the IRQ-handler with interrupts disabled: this is bad for * interrupt latency, but anything else has led to problems on some * machines. * * We enable interrupts in some of the routines after making sure it's * safe. */ static int __init hd_init(void) { int drive; if (register_blkdev(MAJOR_NR, "hd")) return -1; hd_queue = blk_init_queue(do_hd_request, &hd_lock); if (!hd_queue) { unregister_blkdev(MAJOR_NR, "hd"); return -ENOMEM; } blk_queue_max_sectors(hd_queue, 255); init_timer(&device_timer); device_timer.function = hd_times_out; blk_queue_hardsect_size(hd_queue, 512); if (!NR_HD) { /* * We don't know anything about the drive. This means * that you *MUST* specify the drive parameters to the * kernel yourself. * * If we were on an i386, we used to read this info from * the BIOS or CMOS. This doesn't work all that well, * since this assumes that this is a primary or secondary * drive, and if we're using this legacy driver, it's * probably an auxilliary controller added to recover * legacy data off an ST-506 drive. Either way, it's * definitely safest to have the user explicitly specify * the information. */ printk("hd: no drives specified - use hd=cyl,head,sectors" " on kernel command line\n"); goto out; } for (drive = 0 ; drive < NR_HD ; drive++) { struct gendisk *disk = alloc_disk(64); struct hd_i_struct *p = &hd_info[drive]; if (!disk) goto Enomem; disk->major = MAJOR_NR; disk->first_minor = drive << 6; disk->fops = &hd_fops; sprintf(disk->disk_name, "hd%c", 'a'+drive); disk->private_data = p; set_capacity(disk, p->head * p->sect * p->cyl); disk->queue = hd_queue; p->unit = drive; hd_gendisk[drive] = disk; printk("%s: %luMB, CHS=%d/%d/%d\n", disk->disk_name, (unsigned long)get_capacity(disk)/2048, p->cyl, p->head, p->sect); } if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) { printk("hd: unable to get IRQ%d for the hard disk driver\n", HD_IRQ); goto out1; } if (!request_region(HD_DATA, 8, "hd")) { printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA); goto out2; } if (!request_region(HD_CMD, 1, "hd(cmd)")) { printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD); goto out3; } /* Let them fly */ for (drive = 0; drive < NR_HD; drive++) add_disk(hd_gendisk[drive]); return 0; out3: release_region(HD_DATA, 8); out2: free_irq(HD_IRQ, NULL); out1: for (drive = 0; drive < NR_HD; drive++) put_disk(hd_gendisk[drive]); NR_HD = 0; out: del_timer(&device_timer); unregister_blkdev(MAJOR_NR, "hd"); blk_cleanup_queue(hd_queue); return -1; Enomem: while (drive--) put_disk(hd_gendisk[drive]); goto out; } static int __init parse_hd_setup(char *line) { int ints[6]; (void) get_options(line, ARRAY_SIZE(ints), ints); hd_setup(NULL, ints); return 1; } __setup("hd=", parse_hd_setup); late_initcall(hd_init);