From a5d8421b2f03e46f02cc02066b186fdbc0f590a6 Mon Sep 17 00:00:00 2001 From: peter fuerst Date: Mon, 12 Feb 2007 15:20:15 +0100 Subject: [PATCH] [SCSI] wd33c93: Fast SCSI with WD33C93B Attached are patches, which help to utilize more of the WD33C93B SCSI controller's capabilities. 1) Added/changed all the necessary code to enable Burst Mode DMA. Only Single Byte DMA was used before. 2) Added/changed all the necessary code to enable Fast-10 SCSI transfers. 3) The original driver inadvertently used a transfer period of 1000-800ns (the lowest possible transfer rate) for asynchronous data transfers, instead of the (configurable) default period intended for this purpose, if the target responded to a SDTR not with a Reject-message, but with a zero-SDTR. This issue was fixed. Moreover, in case of a Reject the driver used the default-period's initialization-value instead of its (maybe smaller) current value. The missing assignment was added. 4) The driver's commandline- and proc-file-interface was augmented to handle the new options properly. The WD33C93 manual, found at http://www.datasheet.in/datasheet-html/W/D/3/WD33C93B_WesternDigital.pdf.html, was very helpful. Signed-off-by: peter fuerst Signed-off-by: James Bottomley --- drivers/scsi/wd33c93.c | 321 +++++++++++++++++++++++++++++++---------- drivers/scsi/wd33c93.h | 6 + 2 files changed, 248 insertions(+), 79 deletions(-) diff --git a/drivers/scsi/wd33c93.c b/drivers/scsi/wd33c93.c index 835751600e93..fa4e08e508ad 100644 --- a/drivers/scsi/wd33c93.c +++ b/drivers/scsi/wd33c93.c @@ -69,6 +69,11 @@ * Added support for pre -A chips, which don't have advanced features * and will generate CSR_RESEL rather than CSR_RESEL_AM. * Richard Hirst August 2000 + * + * Added support for Burst Mode DMA and Fast SCSI. Enabled the use of + * default_sx_per for asynchronous data transfers. Added adjustment + * of transfer periods in sx_table to the actual input-clock. + * peter fuerst February 2007 */ #include @@ -86,9 +91,11 @@ #include "wd33c93.h" +#define optimum_sx_per(hostdata) (hostdata)->sx_table[1].period_ns -#define WD33C93_VERSION "1.26" -#define WD33C93_DATE "22/Feb/2003" + +#define WD33C93_VERSION "1.26++" +#define WD33C93_DATE "10/Feb/2007" MODULE_AUTHOR("John Shifflett"); MODULE_DESCRIPTION("Generic WD33C93 SCSI driver"); @@ -122,6 +129,13 @@ MODULE_LICENSE("GPL"); * defines in wd33c93.h * - clock:x -x = clock input in MHz for WD33c93 chip. Normal values * would be from 8 through 20. Default is 8. + * - burst:x -x = 1 to use Burst Mode (or Demand-Mode) DMA, x = 0 to use + * Single Byte DMA, which is the default. Argument is + * optional - if not present, same as "burst:1". + * - fast:x -x = 1 to enable Fast SCSI, which is only effective with + * input-clock divisor 4 (WD33C93_FS_16_20), x = 0 to disable + * it, which is the default. Argument is optional - if not + * present, same as "fast:1". * - next -No argument. Used to separate blocks of keywords when * there's more than one host adapter in the system. * @@ -148,7 +162,7 @@ MODULE_LICENSE("GPL"); */ /* Normally, no defaults are specified */ -static char *setup_args[] = { "", "", "", "", "", "", "", "", "" }; +static char *setup_args[] = { "", "", "", "", "", "", "", "", "", "" }; static char *setup_strings; module_param(setup_strings, charp, 0); @@ -298,20 +312,8 @@ read_1_byte(const wd33c93_regs regs) return x; } -static struct sx_period sx_table[] = { - {1, 0x20}, - {252, 0x20}, - {376, 0x30}, - {500, 0x40}, - {624, 0x50}, - {752, 0x60}, - {876, 0x70}, - {1000, 0x00}, - {0, 0} -}; - static int -round_period(unsigned int period) +round_period(unsigned int period, const struct sx_period *sx_table) { int x; @@ -324,17 +326,49 @@ round_period(unsigned int period) return 7; } +/* + * Calculate Synchronous Transfer Register value from SDTR code. + */ static uchar -calc_sync_xfer(unsigned int period, unsigned int offset) +calc_sync_xfer(unsigned int period, unsigned int offset, unsigned int fast, + const struct sx_period *sx_table) { + /* When doing Fast SCSI synchronous data transfers, the corresponding + * value in 'sx_table' is two times the actually used transfer period. + */ uchar result; + if (offset && fast) { + fast = STR_FSS; + period *= 2; + } else { + fast = 0; + } period *= 4; /* convert SDTR code to ns */ - result = sx_table[round_period(period)].reg_value; + result = sx_table[round_period(period,sx_table)].reg_value; result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF; + result |= fast; return result; } +/* + * Calculate SDTR code bytes [3],[4] from period and offset. + */ +static inline void +calc_sync_msg(unsigned int period, unsigned int offset, unsigned int fast, + uchar msg[2]) +{ + /* 'period' is a "normal"-mode value, like the ones in 'sx_table'. The + * actually used transfer period for Fast SCSI synchronous data + * transfers is half that value. + */ + period /= 4; + if (offset && fast) + period /= 2; + msg[0] = period; + msg[1] = offset; +} + int wd33c93_queuecommand(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *)) @@ -632,7 +666,7 @@ wd33c93_execute(struct Scsi_Host *instance) write_wd33c93_count(regs, cmd->SCp.this_residual); write_wd33c93(regs, WD_CONTROL, - CTRL_IDI | CTRL_EDI | CTRL_DMA); + CTRL_IDI | CTRL_EDI | hostdata->dma_mode); hostdata->dma = D_DMA_RUNNING; } } else @@ -712,6 +746,8 @@ transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd, cmd->SCp.ptr = page_address(cmd->SCp.buffer->page) + cmd->SCp.buffer->offset; } + if (!cmd->SCp.this_residual) /* avoid bogus setups */ + return; write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER, hostdata->sync_xfer[cmd->device->id]); @@ -744,7 +780,7 @@ transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd, #ifdef PROC_STATISTICS hostdata->dma_cnt++; #endif - write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_DMA); + write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | hostdata->dma_mode); write_wd33c93_count(regs, cmd->SCp.this_residual); if ((hostdata->level2 >= L2_DATA) || @@ -862,9 +898,6 @@ wd33c93_intr(struct Scsi_Host *instance) hostdata->outgoing_msg[0] |= 0x40; if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) { -#ifdef SYNC_DEBUG - printk(" sending SDTR "); -#endif hostdata->sync_stat[cmd->device->id] = SS_WAITING; @@ -878,14 +911,20 @@ wd33c93_intr(struct Scsi_Host *instance) hostdata->outgoing_msg[2] = 3; hostdata->outgoing_msg[3] = EXTENDED_SDTR; if (hostdata->no_sync & (1 << cmd->device->id)) { - hostdata->outgoing_msg[4] = - hostdata->default_sx_per / 4; - hostdata->outgoing_msg[5] = 0; + calc_sync_msg(hostdata->default_sx_per, 0, + 0, hostdata->outgoing_msg + 4); } else { - hostdata->outgoing_msg[4] = OPTIMUM_SX_PER / 4; - hostdata->outgoing_msg[5] = OPTIMUM_SX_OFF; + calc_sync_msg(optimum_sx_per(hostdata), + OPTIMUM_SX_OFF, + hostdata->fast, + hostdata->outgoing_msg + 4); } hostdata->outgoing_len = 6; +#ifdef SYNC_DEBUG + ucp = hostdata->outgoing_msg + 1; + printk(" sending SDTR %02x03%02x%02x%02x ", + ucp[0], ucp[2], ucp[3], ucp[4]); +#endif } else hostdata->outgoing_len = 1; @@ -1001,8 +1040,13 @@ wd33c93_intr(struct Scsi_Host *instance) #ifdef SYNC_DEBUG printk("-REJ-"); #endif - if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) + if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) { hostdata->sync_stat[cmd->device->id] = SS_SET; + /* we want default_sx_per, not DEFAULT_SX_PER */ + hostdata->sync_xfer[cmd->device->id] = + calc_sync_xfer(hostdata->default_sx_per + / 4, 0, 0, hostdata->sx_table); + } write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK); hostdata->state = S_CONNECTED; break; @@ -1022,7 +1066,10 @@ wd33c93_intr(struct Scsi_Host *instance) switch (ucp[2]) { /* what's the EXTENDED code? */ case EXTENDED_SDTR: - id = calc_sync_xfer(ucp[3], ucp[4]); + /* default to default async period */ + id = calc_sync_xfer(hostdata-> + default_sx_per / 4, 0, + 0, hostdata->sx_table); if (hostdata->sync_stat[cmd->device->id] != SS_WAITING) { @@ -1041,20 +1088,22 @@ wd33c93_intr(struct Scsi_Host *instance) hostdata->outgoing_msg[1] = 3; hostdata->outgoing_msg[2] = EXTENDED_SDTR; - hostdata->outgoing_msg[3] = - hostdata->default_sx_per / - 4; - hostdata->outgoing_msg[4] = 0; + calc_sync_msg(hostdata-> + default_sx_per, 0, + 0, hostdata->outgoing_msg + 3); hostdata->outgoing_len = 5; - hostdata->sync_xfer[cmd->device->id] = - calc_sync_xfer(hostdata-> - default_sx_per - / 4, 0); } else { - hostdata->sync_xfer[cmd->device->id] = id; + if (ucp[4]) /* well, sync transfer */ + id = calc_sync_xfer(ucp[3], ucp[4], + hostdata->fast, + hostdata->sx_table); + else if (ucp[3]) /* very unlikely... */ + id = calc_sync_xfer(ucp[3], ucp[4], + 0, hostdata->sx_table); } + hostdata->sync_xfer[cmd->device->id] = id; #ifdef SYNC_DEBUG - printk("sync_xfer=%02x", + printk(" sync_xfer=%02x\n", hostdata->sync_xfer[cmd->device->id]); #endif hostdata->sync_stat[cmd->device->id] = @@ -1486,7 +1535,7 @@ reset_wd33c93(struct Scsi_Host *instance) write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED); write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER, calc_sync_xfer(hostdata->default_sx_per / 4, - DEFAULT_SX_OFF)); + DEFAULT_SX_OFF, 0, hostdata->sx_table)); write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET); @@ -1512,6 +1561,9 @@ reset_wd33c93(struct Scsi_Host *instance) } else hostdata->chip = C_UNKNOWN_CHIP; + if (hostdata->chip != C_WD33C93B) /* Fast SCSI unavailable */ + hostdata->fast = 0; + write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE); write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED); } @@ -1533,7 +1585,8 @@ wd33c93_host_reset(struct scsi_cmnd * SCpnt) for (i = 0; i < 8; i++) { hostdata->busy[i] = 0; hostdata->sync_xfer[i] = - calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF); + calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF, + 0, hostdata->sx_table); hostdata->sync_stat[i] = SS_UNSET; /* using default sync values */ } hostdata->input_Q = NULL; @@ -1782,6 +1835,98 @@ check_setup_args(char *key, int *flags, int *val, char *buf) return ++x; } +/* + * Calculate internal data-transfer-clock cycle from input-clock + * frequency (/MHz) and fill 'sx_table'. + * + * The original driver used to rely on a fixed sx_table, containing periods + * for (only) the lower limits of the respective input-clock-frequency ranges + * (8-10/12-15/16-20 MHz). Although it seems, that no problems ocurred with + * this setting so far, it might be desirable to adjust the transfer periods + * closer to the really attached, possibly 25% higher, input-clock, since + * - the wd33c93 may really use a significant shorter period, than it has + * negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz + * instead). + * - the wd33c93 may ask the target for a lower transfer rate, than the target + * is capable of (eg. negotiating for an assumed minimum of 252ns instead of + * possible 200ns, which indeed shows up in tests as an approx. 10% lower + * transfer rate). + */ +static inline unsigned int +round_4(unsigned int x) +{ + switch (x & 3) { + case 1: --x; + break; + case 2: ++x; + case 3: ++x; + } + return x; +} + +static void +calc_sx_table(unsigned int mhz, struct sx_period sx_table[9]) +{ + unsigned int d, i; + if (mhz < 11) + d = 2; /* divisor for 8-10 MHz input-clock */ + else if (mhz < 16) + d = 3; /* divisor for 12-15 MHz input-clock */ + else + d = 4; /* divisor for 16-20 MHz input-clock */ + + d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */ + + sx_table[0].period_ns = 1; + sx_table[0].reg_value = 0x20; + for (i = 1; i < 8; i++) { + sx_table[i].period_ns = round_4((i+1)*d / 100); + sx_table[i].reg_value = (i+1)*0x10; + } + sx_table[7].reg_value = 0; + sx_table[8].period_ns = 0; + sx_table[8].reg_value = 0; +} + +/* + * check and, maybe, map an init- or "clock:"- argument. + */ +static uchar +set_clk_freq(int freq, int *mhz) +{ + int x = freq; + if (WD33C93_FS_8_10 == freq) + freq = 8; + else if (WD33C93_FS_12_15 == freq) + freq = 12; + else if (WD33C93_FS_16_20 == freq) + freq = 16; + else if (freq > 7 && freq < 11) + x = WD33C93_FS_8_10; + else if (freq > 11 && freq < 16) + x = WD33C93_FS_12_15; + else if (freq > 15 && freq < 21) + x = WD33C93_FS_16_20; + else { + /* Hmm, wouldn't it be safer to assume highest freq here? */ + x = WD33C93_FS_8_10; + freq = 8; + } + *mhz = freq; + return x; +} + +/* + * to be used with the resync: fast: ... options + */ +static inline void set_resync ( struct WD33C93_hostdata *hd, int mask ) +{ + int i; + for (i = 0; i < 8; i++) + if (mask & (1 << i)) + hd->sync_stat[i] = SS_UNSET; +} + void wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, dma_setup_t setup, dma_stop_t stop, int clock_freq) @@ -1798,7 +1943,8 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, hostdata = (struct WD33C93_hostdata *) instance->hostdata; hostdata->regs = regs; - hostdata->clock_freq = clock_freq; + hostdata->clock_freq = set_clk_freq(clock_freq, &i); + calc_sx_table(i, hostdata->sx_table); hostdata->dma_setup = setup; hostdata->dma_stop = stop; hostdata->dma_bounce_buffer = NULL; @@ -1806,7 +1952,8 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, for (i = 0; i < 8; i++) { hostdata->busy[i] = 0; hostdata->sync_xfer[i] = - calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF); + calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF, + 0, hostdata->sx_table); hostdata->sync_stat[i] = SS_UNSET; /* using default sync values */ #ifdef PROC_STATISTICS hostdata->cmd_cnt[i] = 0; @@ -1828,6 +1975,8 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, hostdata->default_sx_per = DEFAULT_SX_PER; hostdata->no_sync = 0xff; /* sync defaults to off */ hostdata->no_dma = 0; /* default is DMA enabled */ + hostdata->fast = 0; /* default is Fast SCSI transfers disabled */ + hostdata->dma_mode = CTRL_DMA; /* default is Single Byte DMA */ #ifdef PROC_INTERFACE hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS | @@ -1839,6 +1988,11 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, #endif #endif + if (check_setup_args("clock", &flags, &val, buf)) { + hostdata->clock_freq = set_clk_freq(val, &val); + calc_sx_table(val, hostdata->sx_table); + } + if (check_setup_args("nosync", &flags, &val, buf)) hostdata->no_sync = val; @@ -1847,7 +2001,8 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, if (check_setup_args("period", &flags, &val, buf)) hostdata->default_sx_per = - sx_table[round_period((unsigned int) val)].period_ns; + hostdata->sx_table[round_period((unsigned int) val, + hostdata->sx_table)].period_ns; if (check_setup_args("disconnect", &flags, &val, buf)) { if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS)) @@ -1862,17 +2017,12 @@ wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs, if (check_setup_args("debug", &flags, &val, buf)) hostdata->args = val & DB_MASK; - if (check_setup_args("clock", &flags, &val, buf)) { - if (val > 7 && val < 11) - val = WD33C93_FS_8_10; - else if (val > 11 && val < 16) - val = WD33C93_FS_12_15; - else if (val > 15 && val < 21) - val = WD33C93_FS_16_20; - else - val = WD33C93_FS_8_10; - hostdata->clock_freq = val; - } + if (check_setup_args("burst", &flags, &val, buf)) + hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA; + + if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */ + && check_setup_args("fast", &flags, &val, buf)) + hostdata->fast = !!val; if ((i = check_setup_args("next", &flags, &val, buf))) { while (i) @@ -1917,53 +2067,65 @@ wd33c93_proc_info(struct Scsi_Host *instance, char *buf, char **start, off_t off char tbuf[128]; struct WD33C93_hostdata *hd; struct scsi_cmnd *cmd; - int x, i; + int x; static int stop = 0; hd = (struct WD33C93_hostdata *) instance->hostdata; /* If 'in' is TRUE we need to _read_ the proc file. We accept the following - * keywords (same format as command-line, but only ONE per read): + * keywords (same format as command-line, but arguments are not optional): * debug * disconnect * period * resync * proc * nodma + * level2 + * burst + * fast + * nosync */ if (in) { buf[len] = '\0'; - bp = buf; + for (bp = buf; *bp; ) { + while (',' == *bp || ' ' == *bp) + ++bp; if (!strncmp(bp, "debug:", 6)) { - bp += 6; - hd->args = simple_strtoul(bp, NULL, 0) & DB_MASK; + hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK; } else if (!strncmp(bp, "disconnect:", 11)) { - bp += 11; - x = simple_strtoul(bp, NULL, 0); + x = simple_strtoul(bp+11, &bp, 0); if (x < DIS_NEVER || x > DIS_ALWAYS) x = DIS_ADAPTIVE; hd->disconnect = x; } else if (!strncmp(bp, "period:", 7)) { - bp += 7; - x = simple_strtoul(bp, NULL, 0); + x = simple_strtoul(bp+7, &bp, 0); hd->default_sx_per = - sx_table[round_period((unsigned int) x)].period_ns; + hd->sx_table[round_period((unsigned int) x, + hd->sx_table)].period_ns; } else if (!strncmp(bp, "resync:", 7)) { - bp += 7; - x = simple_strtoul(bp, NULL, 0); - for (i = 0; i < 7; i++) - if (x & (1 << i)) - hd->sync_stat[i] = SS_UNSET; + set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0)); } else if (!strncmp(bp, "proc:", 5)) { - bp += 5; - hd->proc = simple_strtoul(bp, NULL, 0); + hd->proc = simple_strtoul(bp+5, &bp, 0); } else if (!strncmp(bp, "nodma:", 6)) { - bp += 6; - hd->no_dma = simple_strtoul(bp, NULL, 0); + hd->no_dma = simple_strtoul(bp+6, &bp, 0); } else if (!strncmp(bp, "level2:", 7)) { - bp += 7; - hd->level2 = simple_strtoul(bp, NULL, 0); + hd->level2 = simple_strtoul(bp+7, &bp, 0); + } else if (!strncmp(bp, "burst:", 6)) { + hd->dma_mode = + simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA; + } else if (!strncmp(bp, "fast:", 5)) { + x = !!simple_strtol(bp+5, &bp, 0); + if (x != hd->fast) + set_resync(hd, 0xff); + hd->fast = x; + } else if (!strncmp(bp, "nosync:", 7)) { + x = simple_strtoul(bp+7, &bp, 0); + set_resync(hd, x ^ hd->no_sync); + hd->no_sync = x; + } else { + break; /* unknown keyword,syntax-error,... */ + } } return len; } @@ -1977,8 +2139,9 @@ wd33c93_proc_info(struct Scsi_Host *instance, char *buf, char **start, off_t off strcat(bp, tbuf); } if (hd->proc & PR_INFO) { - sprintf(tbuf, "\nclock_freq=%02x no_sync=%02x no_dma=%d", - hd->clock_freq, hd->no_sync, hd->no_dma); + sprintf(tbuf, "\nclock_freq=%02x no_sync=%02x no_dma=%d" + " dma_mode=%02x fast=%d", + hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast); strcat(bp, tbuf); strcat(bp, "\nsync_xfer[] = "); for (x = 0; x < 7; x++) { diff --git a/drivers/scsi/wd33c93.h b/drivers/scsi/wd33c93.h index edcb0365cf0c..61ffb860dacc 100644 --- a/drivers/scsi/wd33c93.h +++ b/drivers/scsi/wd33c93.h @@ -155,6 +155,9 @@ #define WD33C93_FS_12_15 OWNID_FS_12 #define WD33C93_FS_16_20 OWNID_FS_16 + /* pass input-clock explicitely. accepted mhz values are 8-10,12-20 */ +#define WD33C93_FS_MHZ(mhz) (mhz) + /* Control register */ #define CTRL_HSP 0x01 #define CTRL_HA 0x02 @@ -253,6 +256,9 @@ struct WD33C93_hostdata { uchar sync_stat[8]; /* status of sync negotiation per target */ uchar no_sync; /* bitmask: don't do sync on these targets */ uchar no_dma; /* set this flag to disable DMA */ + uchar dma_mode; /* DMA Burst Mode or Single Byte DMA */ + uchar fast; /* set this flag to enable Fast SCSI */ + struct sx_period sx_table[9]; /* transfer periods for actual DTC-setting */ #ifdef PROC_INTERFACE uchar proc; /* bitmask: what's in proc output */ #ifdef PROC_STATISTICS