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Diffstat (limited to 'drivers/char/ftape/lowlevel/fdc-isr.c')
-rw-r--r--drivers/char/ftape/lowlevel/fdc-isr.c1170
1 files changed, 1170 insertions, 0 deletions
diff --git a/drivers/char/ftape/lowlevel/fdc-isr.c b/drivers/char/ftape/lowlevel/fdc-isr.c
new file mode 100644
index 000000000000..ad2bc733ae1b
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fdc-isr.c
@@ -0,0 +1,1170 @@
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven,
+ * (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ 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; see the file COPYING. If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fdc-isr.c,v $
+ * $Revision: 1.9 $
+ * $Date: 1997/10/17 23:01:53 $
+ *
+ * This file contains the interrupt service routine and
+ * associated code for the QIC-40/80/3010/3020 floppy-tape driver
+ * "ftape" for Linux.
+ */
+
+#include <asm/io.h>
+#include <asm/dma.h>
+
+#define volatile /* */
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-isr.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-calibr.h"
+#include "../lowlevel/ftape-bsm.h"
+
+/* Global vars.
+ */
+volatile int ft_expected_stray_interrupts;
+volatile int ft_interrupt_seen;
+volatile int ft_seek_completed;
+volatile int ft_hide_interrupt;
+/* Local vars.
+ */
+typedef enum {
+ no_error = 0, id_am_error = 0x01, id_crc_error = 0x02,
+ data_am_error = 0x04, data_crc_error = 0x08,
+ no_data_error = 0x10, overrun_error = 0x20,
+} error_cause;
+static int stop_read_ahead;
+
+
+static void print_error_cause(int cause)
+{
+ TRACE_FUN(ft_t_any);
+
+ switch (cause) {
+ case no_data_error:
+ TRACE(ft_t_noise, "no data error");
+ break;
+ case id_am_error:
+ TRACE(ft_t_noise, "id am error");
+ break;
+ case id_crc_error:
+ TRACE(ft_t_noise, "id crc error");
+ break;
+ case data_am_error:
+ TRACE(ft_t_noise, "data am error");
+ break;
+ case data_crc_error:
+ TRACE(ft_t_noise, "data crc error");
+ break;
+ case overrun_error:
+ TRACE(ft_t_noise, "overrun error");
+ break;
+ default:;
+ }
+ TRACE_EXIT;
+}
+
+static char *fdc_mode_txt(fdc_mode_enum mode)
+{
+ switch (mode) {
+ case fdc_idle:
+ return "fdc_idle";
+ case fdc_reading_data:
+ return "fdc_reading_data";
+ case fdc_seeking:
+ return "fdc_seeking";
+ case fdc_writing_data:
+ return "fdc_writing_data";
+ case fdc_reading_id:
+ return "fdc_reading_id";
+ case fdc_recalibrating:
+ return "fdc_recalibrating";
+ case fdc_formatting:
+ return "fdc_formatting";
+ case fdc_verifying:
+ return "fdc_verifying";
+ default:
+ return "unknown";
+ }
+}
+
+static inline error_cause decode_irq_cause(fdc_mode_enum mode, __u8 st[])
+{
+ error_cause cause = no_error;
+ TRACE_FUN(ft_t_any);
+
+ /* Valid st[], decode cause of interrupt.
+ */
+ switch (st[0] & ST0_INT_MASK) {
+ case FDC_INT_NORMAL:
+ TRACE(ft_t_fdc_dma,"normal completion: %s",fdc_mode_txt(mode));
+ break;
+ case FDC_INT_ABNORMAL:
+ TRACE(ft_t_flow, "abnormal completion %s", fdc_mode_txt(mode));
+ TRACE(ft_t_fdc_dma, "ST0: 0x%02x, ST1: 0x%02x, ST2: 0x%02x",
+ st[0], st[1], st[2]);
+ TRACE(ft_t_fdc_dma,
+ "C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x",
+ st[3], st[4], st[5], st[6]);
+ if (st[1] & 0x01) {
+ if (st[2] & 0x01) {
+ cause = data_am_error;
+ } else {
+ cause = id_am_error;
+ }
+ } else if (st[1] & 0x20) {
+ if (st[2] & 0x20) {
+ cause = data_crc_error;
+ } else {
+ cause = id_crc_error;
+ }
+ } else if (st[1] & 0x04) {
+ cause = no_data_error;
+ } else if (st[1] & 0x10) {
+ cause = overrun_error;
+ }
+ print_error_cause(cause);
+ break;
+ case FDC_INT_INVALID:
+ TRACE(ft_t_flow, "invalid completion %s", fdc_mode_txt(mode));
+ break;
+ case FDC_INT_READYCH:
+ if (st[0] & ST0_SEEK_END) {
+ TRACE(ft_t_flow, "drive poll completed");
+ } else {
+ TRACE(ft_t_flow, "ready change %s",fdc_mode_txt(mode));
+ }
+ break;
+ default:
+ break;
+ }
+ TRACE_EXIT cause;
+}
+
+static void update_history(error_cause cause)
+{
+ switch (cause) {
+ case id_am_error:
+ ft_history.id_am_errors++;
+ break;
+ case id_crc_error:
+ ft_history.id_crc_errors++;
+ break;
+ case data_am_error:
+ ft_history.data_am_errors++;
+ break;
+ case data_crc_error:
+ ft_history.data_crc_errors++;
+ break;
+ case overrun_error:
+ ft_history.overrun_errors++;
+ break;
+ case no_data_error:
+ ft_history.no_data_errors++;
+ break;
+ default:;
+ }
+}
+
+static void skip_bad_sector(buffer_struct * buff)
+{
+ TRACE_FUN(ft_t_any);
+
+ /* Mark sector as soft error and skip it
+ */
+ if (buff->remaining > 0) {
+ ++buff->sector_offset;
+ ++buff->data_offset;
+ --buff->remaining;
+ buff->ptr += FT_SECTOR_SIZE;
+ buff->bad_sector_map >>= 1;
+ } else {
+ /* Hey, what is this????????????? C code: if we shift
+ * more than 31 bits, we get no shift. That's bad!!!!!!
+ */
+ ++buff->sector_offset; /* hack for error maps */
+ TRACE(ft_t_warn, "skipping last sector in segment");
+ }
+ TRACE_EXIT;
+}
+
+static void update_error_maps(buffer_struct * buff, unsigned int error_offset)
+{
+ int hard = 0;
+ TRACE_FUN(ft_t_any);
+
+ if (buff->retry < FT_SOFT_RETRIES) {
+ buff->soft_error_map |= (1 << error_offset);
+ } else {
+ buff->hard_error_map |= (1 << error_offset);
+ buff->soft_error_map &= ~buff->hard_error_map;
+ buff->retry = -1; /* will be set to 0 in setup_segment */
+ hard = 1;
+ }
+ TRACE(ft_t_noise, "sector %d : %s error\n"
+ KERN_INFO "hard map: 0x%08lx\n"
+ KERN_INFO "soft map: 0x%08lx",
+ FT_SECTOR(error_offset), hard ? "hard" : "soft",
+ (long) buff->hard_error_map, (long) buff->soft_error_map);
+ TRACE_EXIT;
+}
+
+static void print_progress(buffer_struct *buff, error_cause cause)
+{
+ TRACE_FUN(ft_t_any);
+
+ switch (cause) {
+ case no_error:
+ TRACE(ft_t_flow,"%d Sector(s) transferred", buff->sector_count);
+ break;
+ case no_data_error:
+ TRACE(ft_t_flow, "Sector %d not found",
+ FT_SECTOR(buff->sector_offset));
+ break;
+ case overrun_error:
+ /* got an overrun error on the first byte, must be a
+ * hardware problem
+ */
+ TRACE(ft_t_bug,
+ "Unexpected error: failing DMA or FDC controller ?");
+ break;
+ case data_crc_error:
+ TRACE(ft_t_flow, "Error in sector %d",
+ FT_SECTOR(buff->sector_offset - 1));
+ break;
+ case id_crc_error:
+ case id_am_error:
+ case data_am_error:
+ TRACE(ft_t_flow, "Error in sector %d",
+ FT_SECTOR(buff->sector_offset));
+ break;
+ default:
+ TRACE(ft_t_flow, "Unexpected error at sector %d",
+ FT_SECTOR(buff->sector_offset));
+ break;
+ }
+ TRACE_EXIT;
+}
+
+/*
+ * Error cause: Amount xferred: Action:
+ *
+ * id_am_error 0 mark bad and skip
+ * id_crc_error 0 mark bad and skip
+ * data_am_error 0 mark bad and skip
+ * data_crc_error % 1024 mark bad and skip
+ * no_data_error 0 retry on write
+ * mark bad and skip on read
+ * overrun_error [ 0..all-1 ] mark bad and skip
+ * no_error all continue
+ */
+
+/* the arg `sector' is returned by the fdc and tells us at which sector we
+ * are positioned at (relative to starting sector of segment)
+ */
+static void determine_verify_progress(buffer_struct *buff,
+ error_cause cause,
+ __u8 sector)
+{
+ TRACE_FUN(ft_t_any);
+
+ if (cause == no_error && sector == 1) {
+ buff->sector_offset = FT_SECTORS_PER_SEGMENT;
+ buff->remaining = 0;
+ if (TRACE_LEVEL >= ft_t_flow) {
+ print_progress(buff, cause);
+ }
+ } else {
+ buff->sector_offset = sector - buff->sect;
+ buff->remaining = FT_SECTORS_PER_SEGMENT - buff->sector_offset;
+ TRACE(ft_t_noise, "%ssector offset: 0x%04x",
+ (cause == no_error) ? "unexpected " : "",
+ buff->sector_offset);
+ switch (cause) {
+ case overrun_error:
+ break;
+#if 0
+ case no_data_error:
+ buff->retry = FT_SOFT_RETRIES;
+ if (buff->hard_error_map &&
+ buff->sector_offset > 1 &&
+ (buff->hard_error_map &
+ (1 << (buff->sector_offset-2)))) {
+ buff->retry --;
+ }
+ break;
+#endif
+ default:
+ buff->retry = FT_SOFT_RETRIES;
+ break;
+ }
+ if (TRACE_LEVEL >= ft_t_flow) {
+ print_progress(buff, cause);
+ }
+ /* Sector_offset points to the problem area Now adjust
+ * sector_offset so it always points one past he failing
+ * sector. I.e. skip the bad sector.
+ */
+ ++buff->sector_offset;
+ --buff->remaining;
+ update_error_maps(buff, buff->sector_offset - 1);
+ }
+ TRACE_EXIT;
+}
+
+static void determine_progress(buffer_struct *buff,
+ error_cause cause,
+ __u8 sector)
+{
+ unsigned int dma_residue;
+ TRACE_FUN(ft_t_any);
+
+ /* Using less preferred order of disable_dma and
+ * get_dma_residue because this seems to fail on at least one
+ * system if reversed!
+ */
+ dma_residue = get_dma_residue(fdc.dma);
+ disable_dma(fdc.dma);
+ if (cause != no_error || dma_residue != 0) {
+ TRACE(ft_t_noise, "%sDMA residue: 0x%04x",
+ (cause == no_error) ? "unexpected " : "",
+ dma_residue);
+ /* adjust to actual value: */
+ if (dma_residue == 0) {
+ /* this happens sometimes with overrun errors.
+ * I don't know whether we could ignore the
+ * overrun error. Play save.
+ */
+ buff->sector_count --;
+ } else {
+ buff->sector_count -= ((dma_residue +
+ (FT_SECTOR_SIZE - 1)) /
+ FT_SECTOR_SIZE);
+ }
+ }
+ /* Update var's influenced by the DMA operation.
+ */
+ if (buff->sector_count > 0) {
+ buff->sector_offset += buff->sector_count;
+ buff->data_offset += buff->sector_count;
+ buff->ptr += (buff->sector_count *
+ FT_SECTOR_SIZE);
+ buff->remaining -= buff->sector_count;
+ buff->bad_sector_map >>= buff->sector_count;
+ }
+ if (TRACE_LEVEL >= ft_t_flow) {
+ print_progress(buff, cause);
+ }
+ if (cause != no_error) {
+ if (buff->remaining == 0) {
+ TRACE(ft_t_warn, "foo?\n"
+ KERN_INFO "count : %d\n"
+ KERN_INFO "offset: %d\n"
+ KERN_INFO "soft : %08x\n"
+ KERN_INFO "hard : %08x",
+ buff->sector_count,
+ buff->sector_offset,
+ buff->soft_error_map,
+ buff->hard_error_map);
+ }
+ /* Sector_offset points to the problem area, except if we got
+ * a data_crc_error. In that case it points one past the
+ * failing sector.
+ *
+ * Now adjust sector_offset so it always points one past he
+ * failing sector. I.e. skip the bad sector.
+ */
+ if (cause != data_crc_error) {
+ skip_bad_sector(buff);
+ }
+ update_error_maps(buff, buff->sector_offset - 1);
+ }
+ TRACE_EXIT;
+}
+
+static int calc_steps(int cmd)
+{
+ if (ftape_current_cylinder > cmd) {
+ return ftape_current_cylinder - cmd;
+ } else {
+ return ftape_current_cylinder + cmd;
+ }
+}
+
+static void pause_tape(int retry, int mode)
+{
+ int result;
+ __u8 out[3] = {FDC_SEEK, ft_drive_sel, 0};
+ TRACE_FUN(ft_t_any);
+
+ /* We'll use a raw seek command to get the tape to rewind and
+ * stop for a retry.
+ */
+ ++ft_history.rewinds;
+ if (qic117_cmds[ftape_current_command].non_intr) {
+ TRACE(ft_t_warn, "motion command may be issued too soon");
+ }
+ if (retry && (mode == fdc_reading_data ||
+ mode == fdc_reading_id ||
+ mode == fdc_verifying)) {
+ ftape_current_command = QIC_MICRO_STEP_PAUSE;
+ ftape_might_be_off_track = 1;
+ } else {
+ ftape_current_command = QIC_PAUSE;
+ }
+ out[2] = calc_steps(ftape_current_command);
+ result = fdc_command(out, 3); /* issue QIC_117 command */
+ ftape_current_cylinder = out[ 2];
+ if (result < 0) {
+ TRACE(ft_t_noise, "qic-pause failed, status = %d", result);
+ } else {
+ ft_location.known = 0;
+ ft_runner_status = idle;
+ ft_hide_interrupt = 1;
+ ftape_tape_running = 0;
+ }
+ TRACE_EXIT;
+}
+
+static void continue_xfer(buffer_struct *buff,
+ fdc_mode_enum mode,
+ unsigned int skip)
+{
+ int write = 0;
+ TRACE_FUN(ft_t_any);
+
+ if (mode == fdc_writing_data || mode == fdc_deleting) {
+ write = 1;
+ }
+ /* This part can be removed if it never happens
+ */
+ if (skip > 0 &&
+ (ft_runner_status != running ||
+ (write && (buff->status != writing)) ||
+ (!write && (buff->status != reading &&
+ buff->status != verifying)))) {
+ TRACE(ft_t_err, "unexpected runner/buffer state %d/%d",
+ ft_runner_status, buff->status);
+ buff->status = error;
+ /* finish this buffer: */
+ (void)ftape_next_buffer(ft_queue_head);
+ ft_runner_status = aborting;
+ fdc_mode = fdc_idle;
+ } else if (buff->remaining > 0 && ftape_calc_next_cluster(buff) > 0) {
+ /* still sectors left in current segment, continue
+ * with this segment
+ */
+ if (fdc_setup_read_write(buff, mode) < 0) {
+ /* failed, abort operation
+ */
+ buff->bytes = buff->ptr - buff->address;
+ buff->status = error;
+ /* finish this buffer: */
+ (void)ftape_next_buffer(ft_queue_head);
+ ft_runner_status = aborting;
+ fdc_mode = fdc_idle;
+ }
+ } else {
+ /* current segment completed
+ */
+ unsigned int last_segment = buff->segment_id;
+ int eot = ((last_segment + 1) % ft_segments_per_track) == 0;
+ unsigned int next = buff->next_segment; /* 0 means stop ! */
+
+ buff->bytes = buff->ptr - buff->address;
+ buff->status = done;
+ buff = ftape_next_buffer(ft_queue_head);
+ if (eot) {
+ /* finished last segment on current track,
+ * can't continue
+ */
+ ft_runner_status = logical_eot;
+ fdc_mode = fdc_idle;
+ TRACE_EXIT;
+ }
+ if (next <= 0) {
+ /* don't continue with next segment
+ */
+ TRACE(ft_t_noise, "no %s allowed, stopping tape",
+ (write) ? "write next" : "read ahead");
+ pause_tape(0, mode);
+ ft_runner_status = idle; /* not quite true until
+ * next irq
+ */
+ TRACE_EXIT;
+ }
+ /* continue with next segment
+ */
+ if (buff->status != waiting) {
+ TRACE(ft_t_noise, "all input buffers %s, pausing tape",
+ (write) ? "empty" : "full");
+ pause_tape(0, mode);
+ ft_runner_status = idle; /* not quite true until
+ * next irq
+ */
+ TRACE_EXIT;
+ }
+ if (write && next != buff->segment_id) {
+ TRACE(ft_t_noise,
+ "segments out of order, aborting write");
+ ft_runner_status = do_abort;
+ fdc_mode = fdc_idle;
+ TRACE_EXIT;
+ }
+ ftape_setup_new_segment(buff, next, 0);
+ if (stop_read_ahead) {
+ buff->next_segment = 0;
+ stop_read_ahead = 0;
+ }
+ if (ftape_calc_next_cluster(buff) == 0 ||
+ fdc_setup_read_write(buff, mode) != 0) {
+ TRACE(ft_t_err, "couldn't start %s-ahead",
+ write ? "write" : "read");
+ ft_runner_status = do_abort;
+ fdc_mode = fdc_idle;
+ } else {
+ /* keep on going */
+ switch (ft_driver_state) {
+ case reading: buff->status = reading; break;
+ case verifying: buff->status = verifying; break;
+ case writing: buff->status = writing; break;
+ case deleting: buff->status = deleting; break;
+ default:
+ TRACE(ft_t_err,
+ "BUG: ft_driver_state %d should be one out of "
+ "{reading, writing, verifying, deleting}",
+ ft_driver_state);
+ buff->status = write ? writing : reading;
+ break;
+ }
+ }
+ }
+ TRACE_EXIT;
+}
+
+static void retry_sector(buffer_struct *buff,
+ int mode,
+ unsigned int skip)
+{
+ TRACE_FUN(ft_t_any);
+
+ TRACE(ft_t_noise, "%s error, will retry",
+ (mode == fdc_writing_data || mode == fdc_deleting) ? "write" : "read");
+ pause_tape(1, mode);
+ ft_runner_status = aborting;
+ buff->status = error;
+ buff->skip = skip;
+ TRACE_EXIT;
+}
+
+static unsigned int find_resume_point(buffer_struct *buff)
+{
+ int i = 0;
+ SectorMap mask;
+ SectorMap map;
+ TRACE_FUN(ft_t_any);
+
+ /* This function is to be called after all variables have been
+ * updated to point past the failing sector.
+ * If there are any soft errors before the failing sector,
+ * find the first soft error and return the sector offset.
+ * Otherwise find the last hard error.
+ * Note: there should always be at least one hard or soft error !
+ */
+ if (buff->sector_offset < 1 || buff->sector_offset > 32) {
+ TRACE(ft_t_bug, "BUG: sector_offset = %d",
+ buff->sector_offset);
+ TRACE_EXIT 0;
+ }
+ if (buff->sector_offset >= 32) { /* C-limitation on shift ! */
+ mask = 0xffffffff;
+ } else {
+ mask = (1 << buff->sector_offset) - 1;
+ }
+ map = buff->soft_error_map & mask;
+ if (map) {
+ while ((map & (1 << i)) == 0) {
+ ++i;
+ }
+ TRACE(ft_t_noise, "at sector %d", FT_SECTOR(i));
+ } else {
+ map = buff->hard_error_map & mask;
+ i = buff->sector_offset - 1;
+ if (map) {
+ while ((map & (1 << i)) == 0) {
+ --i;
+ }
+ TRACE(ft_t_noise, "after sector %d", FT_SECTOR(i));
+ ++i; /* first sector after last hard error */
+ } else {
+ TRACE(ft_t_bug, "BUG: no soft or hard errors");
+ }
+ }
+ TRACE_EXIT i;
+}
+
+/* check possible dma residue when formatting, update position record in
+ * buffer struct. This is, of course, modelled after determine_progress(), but
+ * we don't need to set up for retries because the format process cannot be
+ * interrupted (except at the end of the tape track).
+ */
+static int determine_fmt_progress(buffer_struct *buff, error_cause cause)
+{
+ unsigned int dma_residue;
+ TRACE_FUN(ft_t_any);
+
+ /* Using less preferred order of disable_dma and
+ * get_dma_residue because this seems to fail on at least one
+ * system if reversed!
+ */
+ dma_residue = get_dma_residue(fdc.dma);
+ disable_dma(fdc.dma);
+ if (cause != no_error || dma_residue != 0) {
+ TRACE(ft_t_info, "DMA residue = 0x%04x", dma_residue);
+ fdc_mode = fdc_idle;
+ switch(cause) {
+ case no_error:
+ ft_runner_status = aborting;
+ buff->status = idle;
+ break;
+ case overrun_error:
+ /* got an overrun error on the first byte, must be a
+ * hardware problem
+ */
+ TRACE(ft_t_bug,
+ "Unexpected error: failing DMA controller ?");
+ ft_runner_status = do_abort;
+ buff->status = error;
+ break;
+ default:
+ TRACE(ft_t_noise, "Unexpected error at segment %d",
+ buff->segment_id);
+ ft_runner_status = do_abort;
+ buff->status = error;
+ break;
+ }
+ TRACE_EXIT -EIO; /* can only retry entire track in format mode
+ */
+ }
+ /* Update var's influenced by the DMA operation.
+ */
+ buff->ptr += FT_SECTORS_PER_SEGMENT * 4;
+ buff->bytes -= FT_SECTORS_PER_SEGMENT * 4;
+ buff->remaining -= FT_SECTORS_PER_SEGMENT;
+ buff->segment_id ++; /* done with segment */
+ TRACE_EXIT 0;
+}
+
+/*
+ * Continue formatting, switch buffers if there is no data left in
+ * current buffer. This is, of course, modelled after
+ * continue_xfer(), but we don't need to set up for retries because
+ * the format process cannot be interrupted (except at the end of the
+ * tape track).
+ */
+static void continue_formatting(buffer_struct *buff)
+{
+ TRACE_FUN(ft_t_any);
+
+ if (buff->remaining <= 0) { /* no space left in dma buffer */
+ unsigned int next = buff->next_segment;
+
+ if (next == 0) { /* end of tape track */
+ buff->status = done;
+ ft_runner_status = logical_eot;
+ fdc_mode = fdc_idle;
+ TRACE(ft_t_noise, "Done formatting track %d",
+ ft_location.track);
+ TRACE_EXIT;
+ }
+ /*
+ * switch to next buffer!
+ */
+ buff->status = done;
+ buff = ftape_next_buffer(ft_queue_head);
+
+ if (buff->status != waiting || next != buff->segment_id) {
+ goto format_setup_error;
+ }
+ }
+ if (fdc_setup_formatting(buff) < 0) {
+ goto format_setup_error;
+ }
+ buff->status = formatting;
+ TRACE(ft_t_fdc_dma, "Formatting segment %d on track %d",
+ buff->segment_id, ft_location.track);
+ TRACE_EXIT;
+ format_setup_error:
+ ft_runner_status = do_abort;
+ fdc_mode = fdc_idle;
+ buff->status = error;
+ TRACE(ft_t_err, "Error setting up for segment %d on track %d",
+ buff->segment_id, ft_location.track);
+ TRACE_EXIT;
+
+}
+
+/* this handles writing, read id, reading and formatting
+ */
+static void handle_fdc_busy(buffer_struct *buff)
+{
+ static int no_data_error_count;
+ int retry = 0;
+ error_cause cause;
+ __u8 in[7];
+ int skip;
+ fdc_mode_enum fmode = fdc_mode;
+ TRACE_FUN(ft_t_any);
+
+ if (fdc_result(in, 7) < 0) { /* better get it fast ! */
+ TRACE(ft_t_err,
+ "Probably fatal error during FDC Result Phase\n"
+ KERN_INFO
+ "drive may hang until (power on) reset :-(");
+ /* what to do next ????
+ */
+ TRACE_EXIT;
+ }
+ cause = decode_irq_cause(fdc_mode, in);
+#ifdef TESTING
+ { int i;
+ for (i = 0; i < (int)ft_nr_buffers; ++i)
+ TRACE(ft_t_any, "buffer[%d] status: %d, segment_id: %d",
+ i, ft_buffer[i]->status, ft_buffer[i]->segment_id);
+ }
+#endif
+ if (fmode == fdc_reading_data && ft_driver_state == verifying) {
+ fmode = fdc_verifying;
+ }
+ switch (fmode) {
+ case fdc_verifying:
+ if (ft_runner_status == aborting ||
+ ft_runner_status == do_abort) {
+ TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
+ break;
+ }
+ if (buff->retry > 0) {
+ TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+ }
+ switch (cause) {
+ case no_error:
+ no_data_error_count = 0;
+ determine_verify_progress(buff, cause, in[5]);
+ if (in[2] & 0x40) {
+ /* This should not happen when verifying
+ */
+ TRACE(ft_t_warn,
+ "deleted data in segment %d/%d",
+ buff->segment_id,
+ FT_SECTOR(buff->sector_offset - 1));
+ buff->remaining = 0; /* abort transfer */
+ buff->hard_error_map = EMPTY_SEGMENT;
+ skip = 1;
+ } else {
+ skip = 0;
+ }
+ continue_xfer(buff, fdc_mode, skip);
+ break;
+ case no_data_error:
+ no_data_error_count ++;
+ case overrun_error:
+ retry ++;
+ case id_am_error:
+ case id_crc_error:
+ case data_am_error:
+ case data_crc_error:
+ determine_verify_progress(buff, cause, in[5]);
+ if (cause == no_data_error) {
+ if (no_data_error_count >= 2) {
+ TRACE(ft_t_warn,
+ "retrying because of successive "
+ "no data errors");
+ no_data_error_count = 0;
+ } else {
+ retry --;
+ }
+ } else {
+ no_data_error_count = 0;
+ }
+ if (retry) {
+ skip = find_resume_point(buff);
+ } else {
+ skip = buff->sector_offset;
+ }
+ if (retry && skip < 32) {
+ retry_sector(buff, fdc_mode, skip);
+ } else {
+ continue_xfer(buff, fdc_mode, skip);
+ }
+ update_history(cause);
+ break;
+ default:
+ /* Don't know why this could happen
+ * but find out.
+ */
+ determine_verify_progress(buff, cause, in[5]);
+ retry_sector(buff, fdc_mode, 0);
+ TRACE(ft_t_err, "Error: unexpected error");
+ break;
+ }
+ break;
+ case fdc_reading_data:
+#ifdef TESTING
+ /* I'm sorry, but: NOBODY ever used this trace
+ * messages for ages. I guess that Bas was the last person
+ * that ever really used this (thank you, between the lines)
+ */
+ if (cause == no_error) {
+ TRACE(ft_t_flow,"reading segment %d",buff->segment_id);
+ } else {
+ TRACE(ft_t_noise, "error reading segment %d",
+ buff->segment_id);
+ TRACE(ft_t_noise, "\n"
+ KERN_INFO
+ "IRQ:C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x\n"
+ KERN_INFO
+ "BUF:C: 0x%02x, H: 0x%02x, R: 0x%02x",
+ in[3], in[4], in[5], in[6],
+ buff->cyl, buff->head, buff->sect);
+ }
+#endif
+ if (ft_runner_status == aborting ||
+ ft_runner_status == do_abort) {
+ TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
+ break;
+ }
+ if (buff->bad_sector_map == FAKE_SEGMENT) {
+ /* This condition occurs when reading a `fake'
+ * sector that's not accessible. Doesn't
+ * really matter as we would have ignored it
+ * anyway !
+ *
+ * Chance is that we're past the next segment
+ * now, so the next operation may fail and
+ * result in a retry.
+ */
+ buff->remaining = 0; /* skip failing sector */
+ /* buff->ptr = buff->address; */
+ /* fake success: */
+ continue_xfer(buff, fdc_mode, 1);
+ /* trace calls are expensive: place them AFTER
+ * the real stuff has been done.
+ *
+ */
+ TRACE(ft_t_noise, "skipping empty segment %d (read), size? %d",
+ buff->segment_id, buff->ptr - buff->address);
+ TRACE_EXIT;
+ }
+ if (buff->retry > 0) {
+ TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+ }
+ switch (cause) {
+ case no_error:
+ determine_progress(buff, cause, in[5]);
+ if (in[2] & 0x40) {
+ /* Handle deleted data in header segments.
+ * Skip segment and force read-ahead.
+ */
+ TRACE(ft_t_warn,
+ "deleted data in segment %d/%d",
+ buff->segment_id,
+ FT_SECTOR(buff->sector_offset - 1));
+ buff->deleted = 1;
+ buff->remaining = 0;/*abort transfer */
+ buff->soft_error_map |=
+ (-1L << buff->sector_offset);
+ if (buff->segment_id == 0) {
+ /* stop on next segment */
+ stop_read_ahead = 1;
+ }
+ /* force read-ahead: */
+ buff->next_segment =
+ buff->segment_id + 1;
+ skip = (FT_SECTORS_PER_SEGMENT -
+ buff->sector_offset);
+ } else {
+ skip = 0;
+ }
+ continue_xfer(buff, fdc_mode, skip);
+ break;
+ case no_data_error:
+ /* Tape started too far ahead of or behind the
+ * right sector. This may also happen in the
+ * middle of a segment !
+ *
+ * Handle no-data as soft error. If next
+ * sector fails too, a retry (with needed
+ * reposition) will follow.
+ */
+ retry ++;
+ case id_am_error:
+ case id_crc_error:
+ case data_am_error:
+ case data_crc_error:
+ case overrun_error:
+ retry += (buff->soft_error_map != 0 ||
+ buff->hard_error_map != 0);
+ determine_progress(buff, cause, in[5]);
+#if 1 || defined(TESTING)
+ if (cause == overrun_error) retry ++;
+#endif
+ if (retry) {
+ skip = find_resume_point(buff);
+ } else {
+ skip = buff->sector_offset;
+ }
+ /* Try to resume with next sector on single
+ * errors (let ecc correct it), but retry on
+ * no_data (we'll be past the target when we
+ * get here so we cannot retry) or on
+ * multiple errors (reduce chance on ecc
+ * failure).
+ */
+ /* cH: 23/02/97: if the last sector in the
+ * segment was a hard error, then there is
+ * no sense in a retry. This occasion seldom
+ * occurs but ... @:³²¸`@%&§$
+ */
+ if (retry && skip < 32) {
+ retry_sector(buff, fdc_mode, skip);
+ } else {
+ continue_xfer(buff, fdc_mode, skip);
+ }
+ update_history(cause);
+ break;
+ default:
+ /* Don't know why this could happen
+ * but find out.
+ */
+ determine_progress(buff, cause, in[5]);
+ retry_sector(buff, fdc_mode, 0);
+ TRACE(ft_t_err, "Error: unexpected error");
+ break;
+ }
+ break;
+ case fdc_reading_id:
+ if (cause == no_error) {
+ fdc_cyl = in[3];
+ fdc_head = in[4];
+ fdc_sect = in[5];
+ TRACE(ft_t_fdc_dma,
+ "id read: C: 0x%02x, H: 0x%02x, R: 0x%02x",
+ fdc_cyl, fdc_head, fdc_sect);
+ } else { /* no valid information, use invalid sector */
+ fdc_cyl = fdc_head = fdc_sect = 0;
+ TRACE(ft_t_flow, "Didn't find valid sector Id");
+ }
+ fdc_mode = fdc_idle;
+ break;
+ case fdc_deleting:
+ case fdc_writing_data:
+#ifdef TESTING
+ if (cause == no_error) {
+ TRACE(ft_t_flow, "writing segment %d", buff->segment_id);
+ } else {
+ TRACE(ft_t_noise, "error writing segment %d",
+ buff->segment_id);
+ }
+#endif
+ if (ft_runner_status == aborting ||
+ ft_runner_status == do_abort) {
+ TRACE(ft_t_flow, "aborting %s",fdc_mode_txt(fdc_mode));
+ break;
+ }
+ if (buff->retry > 0) {
+ TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+ }
+ if (buff->bad_sector_map == FAKE_SEGMENT) {
+ /* This condition occurs when trying to write to a
+ * `fake' sector that's not accessible. Doesn't really
+ * matter as it isn't used anyway ! Might be located
+ * at wrong segment, then we'll fail on the next
+ * segment.
+ */
+ TRACE(ft_t_noise, "skipping empty segment (write)");
+ buff->remaining = 0; /* skip failing sector */
+ /* fake success: */
+ continue_xfer(buff, fdc_mode, 1);
+ break;
+ }
+ switch (cause) {
+ case no_error:
+ determine_progress(buff, cause, in[5]);
+ continue_xfer(buff, fdc_mode, 0);
+ break;
+ case no_data_error:
+ case id_am_error:
+ case id_crc_error:
+ case data_am_error:
+ case overrun_error:
+ update_history(cause);
+ determine_progress(buff, cause, in[5]);
+ skip = find_resume_point(buff);
+ retry_sector(buff, fdc_mode, skip);
+ break;
+ default:
+ if (in[1] & 0x02) {
+ TRACE(ft_t_err, "media not writable");
+ } else {
+ TRACE(ft_t_bug, "unforeseen write error");
+ }
+ fdc_mode = fdc_idle;
+ break;
+ }
+ break; /* fdc_deleting || fdc_writing_data */
+ case fdc_formatting:
+ /* The interrupt comes after formatting a segment. We then
+ * have to set up QUICKLY for the next segment. But
+ * afterwards, there is plenty of time.
+ */
+ switch (cause) {
+ case no_error:
+ /* would like to keep most of the formatting stuff
+ * outside the isr code, but timing is too critical
+ */
+ if (determine_fmt_progress(buff, cause) >= 0) {
+ continue_formatting(buff);
+ }
+ break;
+ case no_data_error:
+ case id_am_error:
+ case id_crc_error:
+ case data_am_error:
+ case overrun_error:
+ default:
+ determine_fmt_progress(buff, cause);
+ update_history(cause);
+ if (in[1] & 0x02) {
+ TRACE(ft_t_err, "media not writable");
+ } else {
+ TRACE(ft_t_bug, "unforeseen write error");
+ }
+ break;
+ } /* cause */
+ break;
+ default:
+ TRACE(ft_t_warn, "Warning: unexpected irq during: %s",
+ fdc_mode_txt(fdc_mode));
+ fdc_mode = fdc_idle;
+ break;
+ }
+ TRACE_EXIT;
+}
+
+/* FDC interrupt service routine.
+ */
+void fdc_isr(void)
+{
+ static int isr_active;
+#ifdef TESTING
+ unsigned int t0 = ftape_timestamp();
+#endif
+ TRACE_FUN(ft_t_any);
+
+ if (isr_active++) {
+ --isr_active;
+ TRACE(ft_t_bug, "BUG: nested interrupt, not good !");
+ *fdc.hook = fdc_isr; /* hook our handler into the fdc
+ * code again
+ */
+ TRACE_EXIT;
+ }
+ sti();
+ if (inb_p(fdc.msr) & FDC_BUSY) { /* Entering Result Phase */
+ ft_hide_interrupt = 0;
+ handle_fdc_busy(ftape_get_buffer(ft_queue_head));
+ if (ft_runner_status == do_abort) {
+ /* cease operation, remember tape position
+ */
+ TRACE(ft_t_flow, "runner aborting");
+ ft_runner_status = aborting;
+ ++ft_expected_stray_interrupts;
+ }
+ } else { /* !FDC_BUSY */
+ /* clear interrupt, cause should be gotten by issuing
+ * a Sense Interrupt Status command.
+ */
+ if (fdc_mode == fdc_recalibrating || fdc_mode == fdc_seeking) {
+ if (ft_hide_interrupt) {
+ int st0;
+ int pcn;
+
+ if (fdc_sense_interrupt_status(&st0, &pcn) < 0)
+ TRACE(ft_t_err,
+ "sense interrupt status failed");
+ ftape_current_cylinder = pcn;
+ TRACE(ft_t_flow, "handled hidden interrupt");
+ }
+ ft_seek_completed = 1;
+ fdc_mode = fdc_idle;
+ } else if (!waitqueue_active(&ftape_wait_intr)) {
+ if (ft_expected_stray_interrupts == 0) {
+ TRACE(ft_t_warn, "unexpected stray interrupt");
+ } else {
+ TRACE(ft_t_flow, "expected stray interrupt");
+ --ft_expected_stray_interrupts;
+ }
+ } else {
+ if (fdc_mode == fdc_reading_data ||
+ fdc_mode == fdc_verifying ||
+ fdc_mode == fdc_writing_data ||
+ fdc_mode == fdc_deleting ||
+ fdc_mode == fdc_formatting ||
+ fdc_mode == fdc_reading_id) {
+ if (inb_p(fdc.msr) & FDC_BUSY) {
+ TRACE(ft_t_bug,
+ "***** FDC failure, busy too late");
+ } else {
+ TRACE(ft_t_bug,
+ "***** FDC failure, no busy");
+ }
+ } else {
+ TRACE(ft_t_fdc_dma, "awaited stray interrupt");
+ }
+ }
+ ft_hide_interrupt = 0;
+ }
+ /* Handle sleep code.
+ */
+ if (!ft_hide_interrupt) {
+ ft_interrupt_seen ++;
+ if (waitqueue_active(&ftape_wait_intr)) {
+ wake_up_interruptible(&ftape_wait_intr);
+ }
+ } else {
+ TRACE(ft_t_flow, "hiding interrupt while %s",
+ waitqueue_active(&ftape_wait_intr) ? "waiting":"active");
+ }
+#ifdef TESTING
+ t0 = ftape_timediff(t0, ftape_timestamp());
+ if (t0 >= 1000) {
+ /* only tell us about long calls */
+ TRACE(ft_t_noise, "isr() duration: %5d usec", t0);
+ }
+#endif
+ *fdc.hook = fdc_isr; /* hook our handler into the fdc code again */
+ --isr_active;
+ TRACE_EXIT;
+}