diff options
Diffstat (limited to 'drivers/acorn/block/mfmhd.c')
| -rw-r--r-- | drivers/acorn/block/mfmhd.c | 1416 |
1 files changed, 1416 insertions, 0 deletions
diff --git a/drivers/acorn/block/mfmhd.c b/drivers/acorn/block/mfmhd.c new file mode 100644 index 000000000000..4b65f74d66b1 --- /dev/null +++ b/drivers/acorn/block/mfmhd.c @@ -0,0 +1,1416 @@ +/* + * linux/arch/arm/drivers/block/mfmhd.c + * + * Copyright (C) 1995, 1996 Russell King, Dave Alan Gilbert (gilbertd@cs.man.ac.uk) + * + * MFM hard drive code [experimental] + */ + +/* + * Change list: + * + * 3/2/96:DAG: Started a change list :-) + * Set the hardsect_size pointers up since we are running 256 byte + * sectors + * Added DMA code, put it into the rw_intr + * Moved RCAL out of generic interrupt code - don't want to do it + * while DMA'ing - its now in individual handlers. + * Took interrupt handlers off task queue lists and called + * directly - not sure of implications. + * + * 18/2/96:DAG: Well its reading OK I think, well enough for image file code + * to find the image file; but now I've discovered that I actually + * have to put some code in for image files. + * + * Added stuff for image files; seems to work, but I've not + * got a multisegment image file (I don't think!). + * Put in a hack (yep a real hack) for multiple cylinder reads. + * Not convinced its working. + * + * 5/4/96:DAG: Added asm/hardware.h and use IOC_ macros + * Rewrote dma code in mfm.S (again!) - now takes a word at a time + * from main RAM for speed; still doesn't feel speedy! + * + * 20/4/96:DAG: After rewriting mfm.S a heck of a lot of times and speeding + * things up, I've finally figured out why its so damn slow. + * Linux is only reading a block at a time, and so you never + * get more than 1K per disc revoloution ~=60K/second. + * + * 27/4/96:DAG: On Russell's advice I change ll_rw_blk.c to ask it to + * join adjacent blocks together. Everything falls flat on its + * face. + * Four hours of debugging later; I hadn't realised that + * ll_rw_blk would be so generous as to join blocks whose + * results aren't going into consecutive buffers. + * + * OK; severe rehacking of mfm_rw_interrupt; now end_request's + * as soon as its DMA'd each request. Odd thing is that + * we are sometimes getting interrupts where we are not transferring + * any data; why? Is that what happens when you miss? I doubt + * it; are we too fast? No - its just at command ends. Got 240K/s + * better than before, but RiscOS hits 480K/s + * + * 25/6/96:RMK: Fixed init code to allow the MFM podule to work. Increased the + * number of errors for my Miniscribe drive (8425). + * + * 30/6/96:DAG: Russell suggested that a check drive 0 might turn the LEDs off + * - so in request_done just before it clears Busy it sends a + * check drive 0 - and the LEDs go off!!!! + * + * Added test for mainboard controller. - Removes need for separate + * define. + * + * 13/7/96:DAG: Changed hardware sectore size to 512 in attempt to make + * IM drivers work. + * 21/7/96:DAG: Took out old image file stuff (accessing it now produces an IO + * error.) + * + * 17/8/96:DAG: Ran through indent -kr -i8; evil - all my nice 2 character indents + * gone :-( Hand modified afterwards. + * Took out last remains of the older image map system. + * + * 22/9/96:DAG: Changed mfm.S so it will carry on DMA'ing til; BSY is dropped + * Changed mfm_rw_intr so that it doesn't follow the error + * code until BSY is dropped. Nope - still broke. Problem + * may revolve around when it reads the results for the error + * number? + * + *16/11/96:DAG: Modified for 2.0.18; request_irq changed + * + *17/12/96:RMK: Various cleanups, reorganisation, and the changes for new IO system. + * Improved probe for onboard MFM chip - it was hanging on my A5k. + * Added autodetect CHS code such that we don't rely on the presence + * of an ADFS boot block. Added ioport resource manager calls so + * that we don't clash with already-running hardware (eg. RiscPC Ether + * card slots if someone tries this)! + * + * 17/1/97:RMK: Upgraded to 2.1 kernels. + * + * 4/3/98:RMK: Changed major number to 21. + * + * 27/6/98:RMK: Changed asm/delay.h to linux/delay.h for mdelay(). + */ + +/* + * Possible enhancements: + * Multi-thread the code so that it is possible that while one drive + * is seeking, the other one can be reading data/seeking as well. + * This would be a performance boost with dual drive systems. + */ + +#include <linux/module.h> +#include <linux/config.h> +#include <linux/sched.h> +#include <linux/fs.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/mm.h> +#include <linux/errno.h> +#include <linux/genhd.h> +#include <linux/major.h> +#include <linux/ioport.h> +#include <linux/delay.h> +#include <linux/blkpg.h> + +#include <asm/system.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/uaccess.h> +#include <asm/dma.h> +#include <asm/hardware.h> +#include <asm/ecard.h> +#include <asm/hardware/ioc.h> + +static void (*do_mfm)(void) = NULL; +static struct request_queue *mfm_queue; +static DEFINE_SPINLOCK(mfm_lock); + +#define MAJOR_NR MFM_ACORN_MAJOR +#define QUEUE (mfm_queue) +#define CURRENT elv_next_request(mfm_queue) +/* + * This sort of stuff should be in a header file shared with ide.c, hd.c, xd.c etc + */ +#ifndef HDIO_GETGEO +#define HDIO_GETGEO 0x301 +struct hd_geometry { + unsigned char heads; + unsigned char sectors; + unsigned short cylinders; + unsigned long start; +}; +#endif + + +/* + * Configuration section + * + * This is the maximum number of drives that we accept + */ +#define MFM_MAXDRIVES 2 +/* + * Linux I/O address of onboard MFM controller or 0 to disable this + */ +#define ONBOARD_MFM_ADDRESS ((0x002d0000 >> 2) | 0x80000000) +/* + * Uncomment this to enable debugging in the MFM driver... + */ +#ifndef DEBUG +/*#define DEBUG */ +#endif +/* + * End of configuration + */ + + +/* + * This structure contains all information to do with a particular physical + * device. + */ +struct mfm_info { + unsigned char sectors; + unsigned char heads; + unsigned short cylinders; + unsigned short lowcurrent; + unsigned short precomp; +#define NO_TRACK -1 +#define NEED_1_RECAL -2 +#define NEED_2_RECAL -3 + int cylinder; + struct { + char recal; + char report; + char abort; + } errors; +} mfm_info[MFM_MAXDRIVES]; + +#define MFM_DRV_INFO mfm_info[raw_cmd.dev] + +/* Stuff from the assembly routines */ +extern unsigned int hdc63463_baseaddress; /* Controller base address */ +extern unsigned int hdc63463_irqpolladdress; /* Address to read to test for int */ +extern unsigned int hdc63463_irqpollmask; /* Mask for irq register */ +extern unsigned int hdc63463_dataptr; /* Pointer to kernel data space to DMA */ +extern int hdc63463_dataleft; /* Number of bytes left to transfer */ + + + + +static int lastspecifieddrive; +static unsigned Busy; + +static unsigned int PartFragRead; /* The number of sectors which have been read + during a partial read split over two + cylinders. If 0 it means a partial + read did not occur. */ + +static unsigned int PartFragRead_RestartBlock; /* Where to restart on a split access */ +static unsigned int PartFragRead_SectorsLeft; /* Where to restart on a split access */ + +static int Sectors256LeftInCurrent; /* i.e. 256 byte sectors left in current */ +static int SectorsLeftInRequest; /* i.e. blocks left in the thing mfm_request was called for */ +static int Copy_Sector; /* The 256 byte sector we are currently at - fragments need to know + where to take over */ +static char *Copy_buffer; + + +static void mfm_seek(void); +static void mfm_rerequest(void); +static void mfm_request(void); +static void mfm_specify (void); +static void issue_request(unsigned int block, unsigned int nsect, + struct request *req); + +static unsigned int mfm_addr; /* Controller address */ +static unsigned int mfm_IRQPollLoc; /* Address to read for IRQ information */ +static unsigned int mfm_irqenable; /* Podule IRQ enable location */ +static unsigned char mfm_irq; /* Interrupt number */ +static int mfm_drives = 0; /* drives available */ +static int mfm_status = 0; /* interrupt status */ +static int *errors; + +static struct rawcmd { + unsigned int dev; + unsigned int cylinder; + unsigned int head; + unsigned int sector; + unsigned int cmdtype; + unsigned int cmdcode; + unsigned char cmddata[16]; + unsigned int cmdlen; +} raw_cmd; + +static unsigned char result[16]; + +static struct cont { + void (*interrupt) (void); /* interrupt handler */ + void (*error) (void); /* error handler */ + void (*redo) (void); /* redo handler */ + void (*done) (int st); /* done handler */ +} *cont = NULL; + +#if 0 +static struct tq_struct mfm_tq = {0, 0, (void (*)(void *)) NULL, 0}; +#endif + +int number_mfm_drives = 1; + +/* ------------------------------------------------------------------------------------------ */ +/* + * From the HD63463 data sheet from Hitachi Ltd. + */ + +#define MFM_COMMAND (mfm_addr + 0) +#define MFM_DATAOUT (mfm_addr + 1) +#define MFM_STATUS (mfm_addr + 8) +#define MFM_DATAIN (mfm_addr + 9) + +#define CMD_ABT 0xF0 /* Abort */ +#define CMD_SPC 0xE8 /* Specify */ +#define CMD_TST 0xE0 /* Test */ +#define CMD_RCLB 0xC8 /* Recalibrate */ +#define CMD_SEK 0xC0 /* Seek */ +#define CMD_WFS 0xAB /* Write Format Skew */ +#define CMD_WFM 0xA3 /* Write Format */ +#define CMD_MTB 0x90 /* Memory to buffer */ +#define CMD_CMPD 0x88 /* Compare data */ +#define CMD_WD 0x87 /* Write data */ +#define CMD_RED 0x70 /* Read erroneous data */ +#define CMD_RIS 0x68 /* Read ID skew */ +#define CMD_FID 0x61 /* Find ID */ +#define CMD_RID 0x60 /* Read ID */ +#define CMD_BTM 0x50 /* Buffer to memory */ +#define CMD_CKD 0x48 /* Check data */ +#define CMD_RD 0x40 /* Read data */ +#define CMD_OPBW 0x38 /* Open buffer write */ +#define CMD_OPBR 0x30 /* Open buffer read */ +#define CMD_CKV 0x28 /* Check drive */ +#define CMD_CKE 0x20 /* Check ECC */ +#define CMD_POD 0x18 /* Polling disable */ +#define CMD_POL 0x10 /* Polling enable */ +#define CMD_RCAL 0x08 /* Recall */ + +#define STAT_BSY 0x8000 /* Busy */ +#define STAT_CPR 0x4000 /* Command Parameter Rejection */ +#define STAT_CED 0x2000 /* Command end */ +#define STAT_SED 0x1000 /* Seek end */ +#define STAT_DER 0x0800 /* Drive error */ +#define STAT_ABN 0x0400 /* Abnormal end */ +#define STAT_POL 0x0200 /* Polling */ + +/* ------------------------------------------------------------------------------------------ */ +#ifdef DEBUG +static void console_printf(const char *fmt,...) +{ + static char buffer[2048]; /* Arbitary! */ + extern void console_print(const char *); + unsigned long flags; + va_list ap; + + local_irq_save(flags); + + va_start(ap, fmt); + vsprintf(buffer, fmt, ap); + console_print(buffer); + va_end(fmt); + + local_irq_restore(flags); +}; /* console_printf */ + +#define DBG(x...) console_printf(x) +#else +#define DBG(x...) +#endif + +static void print_status(void) +{ + char *error; + static char *errors[] = { + "no error", + "command aborted", + "invalid command", + "parameter error", + "not initialised", + "rejected TEST", + "no useld", + "write fault", + "not ready", + "no scp", + "in seek", + "invalid NCA", + "invalid step rate", + "seek error", + "over run", + "invalid PHA", + "data field EEC error", + "data field CRC error", + "error corrected", + "data field fatal error", + "no data am", + "not hit", + "ID field CRC error", + "time over", + "no ID am", + "not writable" + }; + if (result[1] < 0x65) + error = errors[result[1] >> 2]; + else + error = "unknown"; + printk("("); + if (mfm_status & STAT_BSY) printk("BSY "); + if (mfm_status & STAT_CPR) printk("CPR "); + if (mfm_status & STAT_CED) printk("CED "); + if (mfm_status & STAT_SED) printk("SED "); + if (mfm_status & STAT_DER) printk("DER "); + if (mfm_status & STAT_ABN) printk("ABN "); + if (mfm_status & STAT_POL) printk("POL "); + printk(") SSB = %X (%s)\n", result[1], error); + +} + +/* ------------------------------------------------------------------------------------- */ + +static void issue_command(int command, unsigned char *cmdb, int len) +{ + int status; +#ifdef DEBUG + int i; + console_printf("issue_command: %02X: ", command); + for (i = 0; i < len; i++) + console_printf("%02X ", cmdb[i]); + console_printf("\n"); +#endif + + do { + status = inw(MFM_STATUS); + } while (status & (STAT_BSY | STAT_POL)); + DBG("issue_command: status after pol/bsy loop: %02X:\n ", status >> 8); + + if (status & (STAT_CPR | STAT_CED | STAT_SED | STAT_DER | STAT_ABN)) { + outw(CMD_RCAL, MFM_COMMAND); + while (inw(MFM_STATUS) & STAT_BSY); + } + status = inw(MFM_STATUS); + DBG("issue_command: status before parameter issue: %02X:\n ", status >> 8); + + while (len > 0) { + outw(cmdb[1] | (cmdb[0] << 8), MFM_DATAOUT); + len -= 2; + cmdb += 2; + } + status = inw(MFM_STATUS); + DBG("issue_command: status before command issue: %02X:\n ", status >> 8); + + outw(command, MFM_COMMAND); + status = inw(MFM_STATUS); + DBG("issue_command: status immediately after command issue: %02X:\n ", status >> 8); +} + +static void wait_for_completion(void) +{ + while ((mfm_status = inw(MFM_STATUS)) & STAT_BSY); +} + +static void wait_for_command_end(void) +{ + int i; + + while (!((mfm_status = inw(MFM_STATUS)) & STAT_CED)); + + for (i = 0; i < 16;) { + int in; + in = inw(MFM_DATAIN); + result[i++] = in >> 8; + result[i++] = in; + } + outw (CMD_RCAL, MFM_COMMAND); +} + +/* ------------------------------------------------------------------------------------- */ + +static void mfm_rw_intr(void) +{ + int old_status; /* Holds status on entry, we read to see if the command just finished */ +#ifdef DEBUG + console_printf("mfm_rw_intr...dataleft=%d\n", hdc63463_dataleft); + print_status(); +#endif + + /* Now don't handle the error until BSY drops */ + if ((mfm_status & (STAT_DER | STAT_ABN)) && ((mfm_status&STAT_BSY)==0)) { + /* Something has gone wrong - let's try that again */ + outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */ + if (cont) { + DBG("mfm_rw_intr: DER/ABN err\n"); + cont->error(); + cont->redo(); + }; + return; + }; + + /* OK so what ever happened it's not an error, now I reckon we are left between + a choice of command end or some data which is ready to be collected */ + /* I think we have to transfer data while the interrupt line is on and its + not any other type of interrupt */ + if (CURRENT->cmd == WRITE) { + extern void hdc63463_writedma(void); + if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) { + printk("mfm_rw_intr: Apparent DMA write request when no more to DMA\n"); + if (cont) { + cont->error(); + cont->redo(); + }; + return; + }; + hdc63463_writedma(); + } else { + extern void hdc63463_readdma(void); + if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) { + printk("mfm_rw_intr: Apparent DMA read request when no more to DMA\n"); + if (cont) { + cont->error(); + cont->redo(); + }; + return; + }; + DBG("Going to try read dma..............status=0x%x, buffer=%p\n", mfm_status, hdc63463_dataptr); + hdc63463_readdma(); + }; /* Read */ + + if (hdc63463_dataptr != ((unsigned int) Copy_buffer + 256)) { + /* If we didn't actually manage to get any data on this interrupt - but why? We got the interrupt */ + /* Ah - well looking at the status its just when we get command end; so no problem */ + /*console_printf("mfm: dataptr mismatch. dataptr=0x%08x Copy_buffer+256=0x%08p\n", + hdc63463_dataptr,Copy_buffer+256); + print_status(); */ + } else { + Sectors256LeftInCurrent--; + Copy_buffer += 256; + Copy_Sector++; + + /* We have come to the end of this request */ + if (!Sectors256LeftInCurrent) { + DBG("mfm: end_request for CURRENT=0x%p CURRENT(sector=%d current_nr_sectors=%d nr_sectors=%d)\n", + CURRENT, CURRENT->sector, CURRENT->current_nr_sectors, CURRENT->nr_sectors); + + CURRENT->nr_sectors -= CURRENT->current_nr_sectors; + CURRENT->sector += CURRENT->current_nr_sectors; + SectorsLeftInRequest -= CURRENT->current_nr_sectors; + + end_request(CURRENT, 1); + if (SectorsLeftInRequest) { + hdc63463_dataptr = (unsigned int) CURRENT->buffer; + Copy_buffer = CURRENT->buffer; + Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2; + errors = &(CURRENT->errors); + /* These should match the present calculations of the next logical sector + on the device + Copy_Sector=CURRENT->sector*2; */ + + if (Copy_Sector != CURRENT->sector * 2) +#ifdef DEBUG + /*console_printf*/printk("mfm: Copy_Sector mismatch. Copy_Sector=%d CURRENT->sector*2=%d\n", + Copy_Sector, CURRENT->sector * 2); +#else + printk("mfm: Copy_Sector mismatch! Eek!\n"); +#endif + }; /* CURRENT */ + }; /* Sectors256LeftInCurrent */ + }; + + old_status = mfm_status; + mfm_status = inw(MFM_STATUS); + if (mfm_status & (STAT_DER | STAT_ABN)) { + /* Something has gone wrong - let's try that again */ + if (cont) { + DBG("mfm_rw_intr: DER/ABN error\n"); + cont->error(); + cont->redo(); + }; + return; + }; + + /* If this code wasn't entered due to command_end but there is + now a command end we must read the command results out. If it was + entered like this then mfm_interrupt_handler would have done the + job. */ + if ((!((old_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) && + ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) { + int len = 0; + while (len < 16) { + int in; + in = inw(MFM_DATAIN); + result[len++] = in >> 8; + result[len++] = in; + }; + }; /* Result read */ + + /*console_printf ("mfm_rw_intr nearexit [%02X]\n", __raw_readb(mfm_IRQPollLoc)); */ + + /* If end of command move on */ + if (mfm_status & (STAT_CED)) { + outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */ + /* End of command - trigger the next command */ + if (cont) { + cont->done(1); + } + DBG("mfm_rw_intr: returned from cont->done\n"); + } else { + /* Its going to generate another interrupt */ + do_mfm = mfm_rw_intr; + }; +} + +static void mfm_setup_rw(void) +{ + DBG("setting up for rw...\n"); + + do_mfm = mfm_rw_intr; + issue_command(raw_cmd.cmdcode, raw_cmd.cmddata, raw_cmd.cmdlen); +} + +static void mfm_recal_intr(void) +{ +#ifdef DEBUG + console_printf("recal intr - status = "); + print_status(); +#endif + outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */ + if (mfm_status & (STAT_DER | STAT_ABN)) { + printk("recal failed\n"); + MFM_DRV_INFO.cylinder = NEED_2_RECAL; + if (cont) { + cont->error(); + cont->redo(); + } + return; + } + /* Thats seek end - we are finished */ + if (mfm_status & STAT_SED) { + issue_command(CMD_POD, NULL, 0); + MFM_DRV_INFO.cylinder = 0; + mfm_seek(); + return; + } + /* Command end without seek end (see data sheet p.20) for parallel seek + - we have to send a POL command to wait for the seek */ + if (mfm_status & STAT_CED) { + do_mfm = mfm_recal_intr; + issue_command(CMD_POL, NULL, 0); + return; + } + printk("recal: unknown status\n"); +} + +static void mfm_seek_intr(void) +{ +#ifdef DEBUG + console_printf("seek intr - status = "); + print_status(); +#endif + outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */ + if (mfm_status & (STAT_DER | STAT_ABN)) { + printk("seek failed\n"); + MFM_DRV_INFO.cylinder = NEED_2_RECAL; + if (cont) { + cont->error(); + cont->redo(); + } + return; + } + if (mfm_status & STAT_SED) { + issue_command(CMD_POD, NULL, 0); + MFM_DRV_INFO.cylinder = raw_cmd.cylinder; + mfm_seek(); + return; + } + if (mfm_status & STAT_CED) { + do_mfm = mfm_seek_intr; + issue_command(CMD_POL, NULL, 0); + return; + } + printk("seek: unknown status\n"); +} + +/* IDEA2 seems to work better - its what RiscOS sets my + * disc to - on its SECOND call to specify! + */ +#define IDEA2 +#ifndef IDEA2 +#define SPEC_SL 0x16 +#define SPEC_SH 0xa9 /* Step pulse high=21, Record Length=001 (256 bytes) */ +#else +#define SPEC_SL 0x00 /* OM2 - SL - step pulse low */ +#define SPEC_SH 0x21 /* Step pulse high=4, Record Length=001 (256 bytes) */ +#endif + +static void mfm_setupspecify (int drive, unsigned char *cmdb) +{ + cmdb[0] = 0x1f; /* OM0 - !SECT,!MOD,!DIF,PADP,ECD,CRCP,CRCI,ACOR */ + cmdb[1] = 0xc3; /* OM1 - DTM,BRST,!CEDM,!SEDM,!DERM,0,AMEX,PSK */ + cmdb[2] = SPEC_SL; /* OM2 - SL - step pulse low */ + cmdb[3] = (number_mfm_drives == 1) ? 0x02 : 0x06; /* 1 or 2 drives */ + cmdb[4] = 0xfc | ((mfm_info[drive].cylinders - 1) >> 8);/* RW time over/high part of number of cylinders */ + cmdb[5] = mfm_info[drive].cylinders - 1; /* low part of number of cylinders */ + cmdb[6] = mfm_info[drive].heads - 1; /* Number of heads */ + cmdb[7] = mfm_info[drive].sectors - 1; /* Number of sectors */ + cmdb[8] = SPEC_SH; + cmdb[9] = 0x0a; /* gap length 1 */ + cmdb[10] = 0x0d; /* gap length 2 */ + cmdb[11] = 0x0c; /* gap length 3 */ + cmdb[12] = (mfm_info[drive].precomp - 1) >> 8; /* pre comp cylinder */ + cmdb[13] = mfm_info[drive].precomp - 1; + cmdb[14] = (mfm_info[drive].lowcurrent - 1) >> 8; /* Low current cylinder */ + cmdb[15] = mfm_info[drive].lowcurrent - 1; +} + +static void mfm_specify (void) +{ + unsigned char cmdb[16]; + + DBG("specify...dev=%d lastspecified=%d\n", raw_cmd.dev, lastspecifieddrive); + mfm_setupspecify (raw_cmd.dev, cmdb); + + issue_command (CMD_SPC, cmdb, 16); + /* Ensure that we will do another specify if we move to the other drive */ + lastspecifieddrive = raw_cmd.dev; + wait_for_completion(); +} + +static void mfm_seek(void) +{ + unsigned char cmdb[4]; + + DBG("seeking...\n"); + if (MFM_DRV_INFO.cylinder < 0) { + do_mfm = mfm_recal_intr; + DBG("mfm_seek: about to call specify\n"); + mfm_specify (); /* DAG added this */ + + cmdb[0] = raw_cmd.dev + 1; + cmdb[1] = 0; + + issue_command(CMD_RCLB, cmdb, 2); + return; + } + if (MFM_DRV_INFO.cylinder != raw_cmd.cylinder) { + cmdb[0] = raw_cmd.dev + 1; + cmdb[1] = 0; /* raw_cmd.head; DAG: My data sheet says this should be 0 */ + cmdb[2] = raw_cmd.cylinder >> 8; + cmdb[3] = raw_cmd.cylinder; + + do_mfm = mfm_seek_intr; + issue_command(CMD_SEK, cmdb, 4); + } else + mfm_setup_rw(); +} + +static void mfm_initialise(void) +{ + DBG("init...\n"); + mfm_seek(); +} + +static void request_done(int uptodate) +{ + DBG("mfm:request_done\n"); + if (uptodate) { + unsigned char block[2] = {0, 0}; + + /* Apparently worked - let's check bytes left to DMA */ + if (hdc63463_dataleft != (PartFragRead_SectorsLeft * 256)) { + printk("mfm: request_done - dataleft=%d - should be %d - Eek!\n", hdc63463_dataleft, PartFragRead_SectorsLeft * 256); + end_request(CURRENT, 0); + Busy = 0; + }; + /* Potentially this means that we've done; but we might be doing + a partial access, (over two cylinders) or we may have a number + of fragments in an image file. First let's deal with partial accesss + */ + if (PartFragRead) { + /* Yep - a partial access */ + + /* and issue the remainder */ + issue_request(PartFragRead_RestartBlock, PartFragRead_SectorsLeft, CURRENT); + return; + } + + /* ah well - perhaps there is another fragment to go */ + + /* Increment pointers/counts to start of next fragment */ + if (SectorsLeftInRequest > 0) printk("mfm: SectorsLeftInRequest>0 - Eek! Shouldn't happen!\n"); + + /* No - its the end of the line */ + /* end_request's should have happened at the end of sector DMAs */ + /* Turns Drive LEDs off - may slow it down? */ + if (!elv_next_request(QUEUE)) + issue_command(CMD_CKV, block, 2); + + Busy = 0; + DBG("request_done: About to mfm_request\n"); + /* Next one please */ + mfm_request(); /* Moved from mfm_rw_intr */ + DBG("request_done: returned from mfm_request\n"); + } else { + printk("mfm:request_done: update=0\n"); + end_request(CURRENT, 0); + Busy = 0; + } +} + +static void error_handler(void) +{ + printk("error detected... status = "); + print_status(); + (*errors)++; + if (*errors > MFM_DRV_INFO.errors.abort) + cont->done(0); + if (*errors > MFM_DRV_INFO.errors.recal) + MFM_DRV_INFO.cylinder = NEED_2_RECAL; +} + +static void rw_interrupt(void) +{ + printk("rw_interrupt\n"); +} + +static struct cont rw_cont = +{ + rw_interrupt, + error_handler, + mfm_rerequest, + request_done +}; + +/* + * Actually gets round to issuing the request - note everything at this + * point is in 256 byte sectors not Linux 512 byte blocks + */ +static void issue_request(unsigned int block, unsigned int nsect, + struct request *req) +{ + struct gendisk *disk = req->rq_disk; + struct mfm_info *p = disk->private_data; + int track, start_head, start_sector; + int sectors_to_next_cyl; + dev = p - mfm_info; + + track = block / p->sectors; + start_sector = block % p->sectors; + start_head = track % p->heads; + + /* First get the number of whole tracks which are free before the next + track */ + sectors_to_next_cyl = (p->heads - (start_head + 1)) * p->sectors; + /* Then add in the number of sectors left on this track */ + sectors_to_next_cyl += (p->sectors - start_sector); + + DBG("issue_request: mfm_info[dev].sectors=%d track=%d\n", p->sectors, track); + + raw_cmd.dev = dev; + raw_cmd.sector = start_sector; + raw_cmd.head = start_head; + raw_cmd.cylinder = track / p->heads; + raw_cmd.cmdtype = CURRENT->cmd; + raw_cmd.cmdcode = CURRENT->cmd == WRITE ? CMD_WD : CMD_RD; + raw_cmd.cmddata[0] = dev + 1; /* DAG: +1 to get US */ + raw_cmd.cmddata[1] = raw_cmd.head; + raw_cmd.cmddata[2] = raw_cmd.cylinder >> 8; + raw_cmd.cmddata[3] = raw_cmd.cylinder; + raw_cmd.cmddata[4] = raw_cmd.head; + raw_cmd.cmddata[5] = raw_cmd.sector; + + /* Was == and worked - how the heck??? */ + if (lastspecifieddrive != raw_cmd.dev) + mfm_specify (); + + if (nsect <= sectors_to_next_cyl) { + raw_cmd.cmddata[6] = nsect >> 8; + raw_cmd.cmddata[7] = nsect; + PartFragRead = 0; /* All in one */ + PartFragRead_SectorsLeft = 0; /* Must set this - used in DMA calcs */ + } else { + raw_cmd.cmddata[6] = sectors_to_next_cyl >> 8; + raw_cmd.cmddata[7] = sectors_to_next_cyl; + PartFragRead = sectors_to_next_cyl; /* only do this many this time */ + PartFragRead_RestartBlock = block + sectors_to_next_cyl; /* Where to restart from */ + PartFragRead_SectorsLeft = nsect - sectors_to_next_cyl; + } + raw_cmd.cmdlen = 8; + + /* Setup DMA pointers */ + hdc63463_dataptr = (unsigned int) Copy_buffer; + hdc63463_dataleft = nsect * 256; /* Better way? */ + + DBG("mfm%c: %sing: CHS=%d/%d/%d, sectors=%d, buffer=0x%08lx (%p)\n", + raw_cmd.dev + 'a', (CURRENT->cmd == READ) ? "read" : "writ", + raw_cmd.cylinder, + raw_cmd.head, + raw_cmd.sector, nsect, (unsigned long) Copy_buffer, CURRENT); + + cont = &rw_cont; + errors = &(CURRENT->errors); +#if 0 + mfm_tq.routine = (void (*)(void *)) mfm_initialise; + queue_task(&mfm_tq, &tq_immediate); + mark_bh(IMMEDIATE_BH); +#else + mfm_initialise(); +#endif +} /* issue_request */ + +/* + * Called when an error has just happened - need to trick mfm_request + * into thinking we weren't busy + * + * Turn off ints - mfm_request expects them this way + */ +static void mfm_rerequest(void) +{ + DBG("mfm_rerequest\n"); + cli(); + Busy = 0; + mfm_request(); +} + +static struct gendisk *mfm_gendisk[2]; + +static void mfm_request(void) +{ + DBG("mfm_request CURRENT=%p Busy=%d\n", CURRENT, Busy); + + /* If we are still processing then return; we will get called again */ + if (Busy) { + /* Again seems to be common in 1.3.45 */ + /*DBG*/printk("mfm_request: Exiting due to busy\n"); + return; + } + Busy = 1; + + while (1) { + unsigned int block, nsect; + struct gendisk *disk; + + DBG("mfm_request: loop start\n"); + sti(); + + DBG("mfm_request: before !CURRENT\n"); + + if (!CURRENT) { + printk("mfm_request: Exiting due to empty queue (pre)\n"); + do_mfm = NULL; + Busy = 0; + return; + } + + DBG("mfm_request: before arg extraction\n"); + + disk = CURRENT->rq_disk; + block = CURRENT->sector; + nsect = CURRENT->nr_sectors; + if (block >= get_capacity(disk) || + block+nsect > get_capacity(disk)) { + printk("%s: bad access: block=%d, count=%d, nr_sects=%ld\n", + disk->disk_name, block, nsect, get_capacity(disk)); + printk("mfm: continue 1\n"); + end_request(CURRENT, 0); + Busy = 0; + continue; + } + + /* DAG: Linux doesn't cope with this - even though it has an array telling + it the hardware block size - silly */ + block <<= 1; /* Now in 256 byte sectors */ + nsect <<= 1; /* Ditto */ + + SectorsLeftInRequest = nsect >> 1; + Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2; + Copy_buffer = CURRENT->buffer; + Copy_Sector = CURRENT->sector << 1; + + DBG("mfm_request: block after offset=%d\n", block); + + if (CURRENT->cmd != READ && CURRENT->cmd != WRITE) { + printk("unknown mfm-command %d\n", CURRENT->cmd); + end_request(CURRENT, 0); + Busy = 0; + printk("mfm: continue 4\n"); + continue; + } + issue_request(block, nsect, CURRENT); + + break; + } + DBG("mfm_request: Dropping out bottom\n"); +} + +static void do_mfm_request(request_queue_t *q) +{ + DBG("do_mfm_request: about to mfm_request\n"); + mfm_request(); +} + +static void mfm_interrupt_handler(int unused, void *dev_id, struct pt_regs *regs) +{ + void (*handler) (void) = do_mfm; + + do_mfm = NULL; + + DBG("mfm_interrupt_handler (handler=0x%p)\n", handler); + + mfm_status = inw(MFM_STATUS); + + /* If CPR (Command Parameter Reject) and not busy it means that the command + has some return message to give us */ + if ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR) { + int len = 0; + while (len < 16) { + int in; + in = inw(MFM_DATAIN); + result[len++] = in >> 8; + result[len++] = in; + } + } + if (handler) { + handler(); + return; + } + outw (CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */ + printk ("mfm: unexpected interrupt - status = "); + print_status (); + while (1); +} + + + + + +/* + * Tell the user about the drive if we decided it exists. + */ +static void mfm_geometry(int drive) +{ + struct mfm_info *p = mfm_info + drive; + struct gendisk *disk = mfm_gendisk[drive]; + disk->private_data = p; + if (p->cylinders) + printk ("%s: %dMB CHS=%d/%d/%d LCC=%d RECOMP=%d\n", + disk->disk_name, + p->cylinders * p->heads * p->sectors / 4096, + p->cylinders, p->heads, p->sectors, + p->lowcurrent, p->precomp); + set_capacity(disk, p->cylinders * p->heads * p->sectors / 2); +} + +#ifdef CONFIG_BLK_DEV_MFM_AUTODETECT +/* + * Attempt to detect a drive and find its geometry. The drive has already been + * specified... + * + * We first recalibrate the disk, then try to probe sectors, heads and then + * cylinders. NOTE! the cylinder probe may break drives. The xd disk driver + * does something along these lines, so I assume that most drives are up to + * this mistreatment... + */ +static int mfm_detectdrive (int drive) +{ + unsigned int mingeo[3], maxgeo[3]; + unsigned int attribute, need_recal = 1; + unsigned char cmdb[8]; + + memset (mingeo, 0, sizeof (mingeo)); + maxgeo[0] = mfm_info[drive].sectors; + maxgeo[1] = mfm_info[drive].heads; + maxgeo[2] = mfm_info[drive].cylinders; + + cmdb[0] = drive + 1; + cmdb[6] = 0; + cmdb[7] = 1; + for (attribute = 0; attribute < 3; attribute++) { + while (mingeo[attribute] != maxgeo[attribute]) { + unsigned int variable; + + variable = (maxgeo[attribute] + mingeo[attribute]) >> 1; + cmdb[1] = cmdb[2] = cmdb[3] = cmdb[4] = cmdb[5] = 0; + + if (need_recal) { + int tries = 5; + + do { + issue_command (CMD_RCLB, cmdb, 2); + wait_for_completion (); + wait_for_command_end (); + if (result[1] == 0x20) + break; + } while (result[1] && --tries); + if (result[1]) { + outw (CMD_RCAL, MFM_COMMAND); + return 0; + } + need_recal = 0; + } + + switch (attribute) { + case 0: + cmdb[5] = variable; + issue_command (CMD_CMPD, cmdb, 8); + break; + case 1: + cmdb[1] = variable; + cmdb[4] = variable; + issue_command (CMD_CMPD, cmdb, 8); + break; + case 2: + cmdb[2] = variable >> 8; + cmdb[3] = variable; + issue_command (CMD_SEK, cmdb, 4); + break; + } + wait_for_completion (); + wait_for_command_end (); + + switch (result[1]) { + case 0x00: + case 0x50: + mingeo[attribute] = variable + 1; + break; + + case 0x20: + outw (CMD_RCAL, MFM_COMMAND); + return 0; + + case 0x24: + need_recal = 1; + default: + maxgeo[attribute] = variable; + break; + } + } + } + mfm_info[drive].cylinders = mingeo[2]; + mfm_info[drive].lowcurrent = mingeo[2]; + mfm_info[drive].precomp = mingeo[2] / 2; + mfm_info[drive].heads = mingeo[1]; + mfm_info[drive].sectors = mingeo[0]; + outw (CMD_RCAL, MFM_COMMAND); + return 1; +} +#endif + +/* + * Initialise all drive information for this controller. + */ +static int mfm_initdrives(void) +{ + int drive; + + if (number_mfm_drives > MFM_MAXDRIVES) { + number_mfm_drives = MFM_MAXDRIVES; + printk("No. of ADFS MFM drives is greater than MFM_MAXDRIVES - you can't have that many!\n"); + } + + for (drive = 0; drive < number_mfm_drives; drive++) { + mfm_info[drive].lowcurrent = 1; + mfm_info[drive].precomp = 1; + mfm_info[drive].cylinder = -1; + mfm_info[drive].errors.recal = 0; + mfm_info[drive].errors.report = 0; + mfm_info[drive].errors.abort = 4; + +#ifdef CONFIG_BLK_DEV_MFM_AUTODETECT + mfm_info[drive].cylinders = 1024; + mfm_info[drive].heads = 8; + mfm_info[drive].sectors = 64; + { + unsigned char cmdb[16]; + + mfm_setupspecify (drive, cmdb); + cmdb[1] &= ~0x81; + issue_command (CMD_SPC, cmdb, 16); + wait_for_completion (); + if (!mfm_detectdrive (drive)) { + mfm_info[drive].cylinders = 0; + mfm_info[drive].heads = 0; + mfm_info[drive].sectors = 0; + } + cmdb[0] = cmdb[1] = 0; + issue_command (CMD_CKV, cmdb, 2); + } +#else + mfm_info[drive].cylinders = 1; /* its going to have to figure it out from the partition info */ + mfm_info[drive].heads = 4; + mfm_info[drive].sectors = 32; +#endif + } + return number_mfm_drives; +} + + + +/* + * The 'front' end of the mfm driver follows... + */ + +static int mfm_ioctl(struct inode *inode, struct file *file, u_int cmd, u_long arg) +{ + struct mfm_info *p = inode->i_bdev->bd_disk->private_data; + struct hd_geometry *geo = (struct hd_geometry *) arg; + if (cmd != HDIO_GETGEO) + return -EINVAL; + if (!arg) + return -EINVAL; + if (put_user (p->heads, &geo->heads)) + return -EFAULT; + if (put_user (p->sectors, &geo->sectors)) + return -EFAULT; + if (put_user (p->cylinders, &geo->cylinders)) + return -EFAULT; + if (put_user (get_start_sect(inode->i_bdev), &geo->start)) + return -EFAULT; + return 0; +} + +/* + * This is to handle various kernel command line parameters + * specific to this driver. + */ +void mfm_setup(char *str, int *ints) +{ + return; +} + +/* + * Set the CHS from the ADFS boot block if it is present. This is not ideal + * since if there are any non-ADFS partitions on the disk, this won't work! + * Hence, I want to get rid of this... + */ +void xd_set_geometry(struct block_device *bdev, unsigned char secsptrack, + unsigned char heads, unsigned int secsize) +{ + struct mfm_info *p = bdev->bd_disk->private_data; + int drive = p - mfm_info; + unsigned long disksize = bdev->bd_inode->i_size; + + if (p->cylinders == 1) { + p->sectors = secsptrack; + p->heads = heads; + p->cylinders = discsize / (secsptrack * heads * secsize); + + if ((heads < 1) || (p->cylinders > 1024)) { + printk("%s: Insane disc shape! Setting to 512/4/32\n", + bdev->bd_disk->disk_name); + + /* These values are fairly arbitary, but are there so that if your + * lucky you can pick apart your disc to find out what is going on - + * I reckon these figures won't hurt MOST drives + */ + p->sectors = 32; + p->heads = 4; + p->cylinders = 512; + } + if (raw_cmd.dev == drive) + mfm_specify (); + mfm_geometry (drive); + } +} + +static struct block_device_operations mfm_fops = +{ + .owner = THIS_MODULE, + .ioctl = mfm_ioctl, +}; + +/* + * See if there is a controller at the address presently at mfm_addr + * + * We check to see if the controller is busy - if it is, we abort it first, + * and check that the chip is no longer busy after at least 180 clock cycles. + * We then issue a command and check that the BSY or CPR bits are set. + */ +static int mfm_probecontroller (unsigned int mfm_addr) +{ + if (inw (MFM_STATUS) & STAT_BSY) { + outw (CMD_ABT, MFM_COMMAND); + udelay (50); + if (inw (MFM_STATUS) & STAT_BSY) + return 0; + } + + if (inw (MFM_STATUS) & STAT_CED) + outw (CMD_RCAL, MFM_COMMAND); + + outw (CMD_SEK, MFM_COMMAND); + + if (inw (MFM_STATUS) & (STAT_BSY | STAT_CPR)) { + unsigned int count = 2000; + while (inw (MFM_STATUS) & STAT_BSY) { + udelay (500); + if (!--count) + return 0; + } + + outw (CMD_RCAL, MFM_COMMAND); + } + return 1; +} + +static int mfm_do_init(unsigned char irqmask) +{ + int i, ret; + + printk("mfm: found at address %08X, interrupt %d\n", mfm_addr, mfm_irq); + + ret = -EBUSY; + if (!request_region (mfm_addr, 10, "mfm")) + goto out1; + + ret = register_blkdev(MAJOR_NR, "mfm"); + if (ret) + goto out2; + + /* Stuff for the assembler routines to get to */ + hdc63463_baseaddress = ioaddr(mfm_addr); + hdc63463_irqpolladdress = mfm_IRQPollLoc; + hdc63463_irqpollmask = irqmask; + + mfm_queue = blk_init_queue(do_mfm_request, &mfm_lock); + if (!mfm_queue) + goto out2a; + + Busy = 0; + lastspecifieddrive = -1; + + mfm_drives = mfm_initdrives(); + if (!mfm_drives) { + ret = -ENODEV; + goto out3; + } + + for (i = 0; i < mfm_drives; i++) { + struct gendisk *disk = alloc_disk(64); + if (!disk) + goto Enomem; + disk->major = MAJOR_NR; + disk->first_minor = i << 6; + disk->fops = &mfm_fops; + sprintf(disk->disk_name, "mfm%c", 'a'+i); + mfm_gendisk[i] = disk; + } + + printk("mfm: detected %d hard drive%s\n", mfm_drives, + mfm_drives == 1 ? "" : "s"); + ret = request_irq(mfm_irq, mfm_interrupt_handler, SA_INTERRUPT, "MFM harddisk", NULL); + if (ret) { + printk("mfm: unable to get IRQ%d\n", mfm_irq); + goto out4; + } + + if (mfm_irqenable) + outw(0x80, mfm_irqenable); /* Required to enable IRQs from MFM podule */ + + for (i = 0; i < mfm_drives; i++) { + mfm_geometry(i); + mfm_gendisk[i]->queue = mfm_queue; + add_disk(mfm_gendisk[i]); + } + return 0; + +out4: + for (i = 0; i < mfm_drives; i++) + put_disk(mfm_gendisk[i]); +out3: + blk_cleanup_queue(mfm_queue); +out2a: + unregister_blkdev(MAJOR_NR, "mfm"); +out2: + release_region(mfm_addr, 10); +out1: + return ret; +Enomem: + while (i--) + put_disk(mfm_gendisk[i]); + goto out3; +} + +static void mfm_do_exit(void) +{ + int i; + + free_irq(mfm_irq, NULL); + for (i = 0; i < mfm_drives; i++) { + del_gendisk(mfm_gendisk[i]); + put_disk(mfm_gendisk[i]); + } + blk_cleanup_queue(mfm_queue); + unregister_blkdev(MAJOR_NR, "mfm"); + if (mfm_addr) + release_region(mfm_addr, 10); +} + +static int __devinit mfm_probe(struct expansion_card *ec, struct ecard_id *id) +{ + if (mfm_addr) + return -EBUSY; + + mfm_addr = ecard_address(ec, ECARD_IOC, ECARD_MEDIUM) + 0x800; + mfm_IRQPollLoc = ioaddr(mfm_addr + 0x400); + mfm_irqenable = mfm_IRQPollLoc; + mfm_irq = ec->irq; + + return mfm_do_init(0x08); +} + +static void __devexit mfm_remove(struct expansion_card *ec) +{ + outw (0, mfm_irqenable); /* Required to enable IRQs from MFM podule */ + mfm_do_exit(); +} + +static const struct ecard_id mfm_cids[] = { + { MANU_ACORN, PROD_ACORN_MFM }, + { 0xffff, 0xffff }, +}; + +static struct ecard_driver mfm_driver = { + .probe = mfm_probe, + .remove = __devexit(mfm_remove), + .id_table = mfm_cids, + .drv = { + .name = "mfm", + }, +}; + +/* + * Look for a MFM controller - first check the motherboard, then the podules + * The podules have an extra interrupt enable that needs to be played with + * + * The HDC is accessed at MEDIUM IOC speeds. + */ +static int __init mfm_init (void) +{ + unsigned char irqmask; + + if (mfm_probecontroller(ONBOARD_MFM_ADDRESS)) { + mfm_addr = ONBOARD_MFM_ADDRESS; + mfm_IRQPollLoc = IOC_IRQSTATB; + mfm_irqenable = 0; + mfm_irq = IRQ_HARDDISK; + return mfm_do_init(0x08); /* IL3 pin */ + } else { + return ecard_register_driver(&mfm_driver); + } +} + +static void __exit mfm_exit(void) +{ + if (mfm_addr == ONBOARD_MFM_ADDRESS) + mfm_do_exit(); + else + ecard_unregister_driver(&mfm_driver); +} + +module_init(mfm_init) +module_exit(mfm_exit) +MODULE_LICENSE("GPL"); |