From f41b5cec9bd6fec1b11b74500f5fb9c3e6e808b2 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Mon, 3 Apr 2006 08:19:34 +0200 Subject: [SCSI] aic79xx bus reset update As James B. correctly noted, ahd_reset_channel() in ahd_linux_bus_reset() should be protected by ahd_lock(). However, the main reason for not doing so was a deadlock with the interesting polling mechanism to detect the end a bus reset. This patch replaces the polling mechanism with a saner signalling via flags; it also gives us the benefit of detecting any multiple calls to ahd_reset_channel(). Signed-off-by: Hannes Reinecke Signed-off-by: James Bottomley --- drivers/scsi/aic7xxx/aic79xx.h | 2 +- drivers/scsi/aic7xxx/aic79xx_core.c | 114 +++++++++++++++++------------------- drivers/scsi/aic7xxx/aic79xx_osm.c | 4 ++ 3 files changed, 58 insertions(+), 62 deletions(-) (limited to 'drivers') diff --git a/drivers/scsi/aic7xxx/aic79xx.h b/drivers/scsi/aic7xxx/aic79xx.h index 1d11f7e..933e510 100644 --- a/drivers/scsi/aic7xxx/aic79xx.h +++ b/drivers/scsi/aic7xxx/aic79xx.h @@ -372,7 +372,7 @@ typedef enum { AHD_CURRENT_SENSING = 0x40000, AHD_SCB_CONFIG_USED = 0x80000,/* No SEEPROM but SCB had info. */ AHD_HP_BOARD = 0x100000, - AHD_RESET_POLL_ACTIVE = 0x200000, + AHD_BUS_RESET_ACTIVE = 0x200000, AHD_UPDATE_PEND_CMDS = 0x400000, AHD_RUNNING_QOUTFIFO = 0x800000, AHD_HAD_FIRST_SEL = 0x1000000 diff --git a/drivers/scsi/aic7xxx/aic79xx_core.c b/drivers/scsi/aic7xxx/aic79xx_core.c index 326a622..880a10d 100644 --- a/drivers/scsi/aic7xxx/aic79xx_core.c +++ b/drivers/scsi/aic7xxx/aic79xx_core.c @@ -207,7 +207,6 @@ static void ahd_add_scb_to_free_list(struct ahd_softc *ahd, static u_int ahd_rem_wscb(struct ahd_softc *ahd, u_int scbid, u_int prev, u_int next, u_int tid); static void ahd_reset_current_bus(struct ahd_softc *ahd); -static ahd_callback_t ahd_reset_poll; static ahd_callback_t ahd_stat_timer; #ifdef AHD_DUMP_SEQ static void ahd_dumpseq(struct ahd_softc *ahd); @@ -1534,6 +1533,18 @@ ahd_handle_scsiint(struct ahd_softc *ahd, u_int intstat) lqistat1 = ahd_inb(ahd, LQISTAT1); lqostat0 = ahd_inb(ahd, LQOSTAT0); busfreetime = ahd_inb(ahd, SSTAT2) & BUSFREETIME; + + /* + * Ignore external resets after a bus reset. + */ + if (((status & SCSIRSTI) != 0) && (ahd->flags & AHD_BUS_RESET_ACTIVE)) + return; + + /* + * Clear bus reset flag + */ + ahd->flags &= ~AHD_BUS_RESET_ACTIVE; + if ((status0 & (SELDI|SELDO)) != 0) { u_int simode0; @@ -7847,6 +7858,17 @@ ahd_reset_channel(struct ahd_softc *ahd, char channel, int initiate_reset) int found; u_int fifo; u_int next_fifo; + uint8_t scsiseq; + + /* + * Check if the last bus reset is cleared + */ + if (ahd->flags & AHD_BUS_RESET_ACTIVE) { + printf("%s: bus reset still active\n", + ahd_name(ahd)); + return 0; + } + ahd->flags |= AHD_BUS_RESET_ACTIVE; ahd->pending_device = NULL; @@ -7860,6 +7882,12 @@ ahd_reset_channel(struct ahd_softc *ahd, char channel, int initiate_reset) /* Make sure the sequencer is in a safe location. */ ahd_clear_critical_section(ahd); + /* + * Run our command complete fifos to ensure that we perform + * completion processing on any commands that 'completed' + * before the reset occurred. + */ + ahd_run_qoutfifo(ahd); #ifdef AHD_TARGET_MODE if ((ahd->flags & AHD_TARGETROLE) != 0) { ahd_run_tqinfifo(ahd, /*paused*/TRUE); @@ -7924,30 +7952,14 @@ ahd_reset_channel(struct ahd_softc *ahd, char channel, int initiate_reset) ahd_clear_fifo(ahd, 1); /* - * Revert to async/narrow transfers until we renegotiate. + * Reenable selections */ - max_scsiid = (ahd->features & AHD_WIDE) ? 15 : 7; - for (target = 0; target <= max_scsiid; target++) { - - if (ahd->enabled_targets[target] == NULL) - continue; - for (initiator = 0; initiator <= max_scsiid; initiator++) { - struct ahd_devinfo devinfo; - - ahd_compile_devinfo(&devinfo, target, initiator, - CAM_LUN_WILDCARD, - 'A', ROLE_UNKNOWN); - ahd_set_width(ahd, &devinfo, MSG_EXT_WDTR_BUS_8_BIT, - AHD_TRANS_CUR, /*paused*/TRUE); - ahd_set_syncrate(ahd, &devinfo, /*period*/0, - /*offset*/0, /*ppr_options*/0, - AHD_TRANS_CUR, /*paused*/TRUE); - } - } + ahd_outb(ahd, SIMODE1, ahd_inb(ahd, SIMODE1) | ENSCSIRST); + scsiseq = ahd_inb(ahd, SCSISEQ_TEMPLATE); + ahd_outb(ahd, SCSISEQ1, scsiseq & (ENSELI|ENRSELI|ENAUTOATNP)); -#ifdef AHD_TARGET_MODE max_scsiid = (ahd->features & AHD_WIDE) ? 15 : 7; - +#ifdef AHD_TARGET_MODE /* * Send an immediate notify ccb to all target more peripheral * drivers affected by this action. @@ -7975,51 +7987,31 @@ ahd_reset_channel(struct ahd_softc *ahd, char channel, int initiate_reset) /* Notify the XPT that a bus reset occurred */ ahd_send_async(ahd, devinfo.channel, CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD, AC_BUS_RESET, NULL); - ahd_restart(ahd); + /* - * Freeze the SIMQ until our poller can determine that - * the bus reset has really gone away. We set the initial - * timer to 0 to have the check performed as soon as possible - * from the timer context. + * Revert to async/narrow transfers until we renegotiate. */ - if ((ahd->flags & AHD_RESET_POLL_ACTIVE) == 0) { - ahd->flags |= AHD_RESET_POLL_ACTIVE; - ahd_freeze_simq(ahd); - ahd_timer_reset(&ahd->reset_timer, 0, ahd_reset_poll, ahd); - } - return (found); -} + for (target = 0; target <= max_scsiid; target++) { + if (ahd->enabled_targets[target] == NULL) + continue; + for (initiator = 0; initiator <= max_scsiid; initiator++) { + struct ahd_devinfo devinfo; -#define AHD_RESET_POLL_US 1000 -static void -ahd_reset_poll(void *arg) -{ - struct ahd_softc *ahd = arg; - u_int scsiseq1; - u_long s; - - ahd_lock(ahd, &s); - ahd_pause(ahd); - ahd_update_modes(ahd); - ahd_set_modes(ahd, AHD_MODE_SCSI, AHD_MODE_SCSI); - ahd_outb(ahd, CLRSINT1, CLRSCSIRSTI); - if ((ahd_inb(ahd, SSTAT1) & SCSIRSTI) != 0) { - ahd_timer_reset(&ahd->reset_timer, AHD_RESET_POLL_US, - ahd_reset_poll, ahd); - ahd_unpause(ahd); - ahd_unlock(ahd, &s); - return; + ahd_compile_devinfo(&devinfo, target, initiator, + CAM_LUN_WILDCARD, + 'A', ROLE_UNKNOWN); + ahd_set_width(ahd, &devinfo, MSG_EXT_WDTR_BUS_8_BIT, + AHD_TRANS_CUR, /*paused*/TRUE); + ahd_set_syncrate(ahd, &devinfo, /*period*/0, + /*offset*/0, /*ppr_options*/0, + AHD_TRANS_CUR, /*paused*/TRUE); + } } - /* Reset is now low. Complete chip reinitialization. */ - ahd_outb(ahd, SIMODE1, ahd_inb(ahd, SIMODE1) | ENSCSIRST); - scsiseq1 = ahd_inb(ahd, SCSISEQ_TEMPLATE); - ahd_outb(ahd, SCSISEQ1, scsiseq1 & (ENSELI|ENRSELI|ENAUTOATNP)); - ahd_unpause(ahd); - ahd->flags &= ~AHD_RESET_POLL_ACTIVE; - ahd_unlock(ahd, &s); - ahd_release_simq(ahd); + ahd_restart(ahd); + + return (found); } /**************************** Statistics Processing ***************************/ diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c index bcced0a..66e4a47 100644 --- a/drivers/scsi/aic7xxx/aic79xx_osm.c +++ b/drivers/scsi/aic7xxx/aic79xx_osm.c @@ -782,6 +782,7 @@ ahd_linux_bus_reset(struct scsi_cmnd *cmd) { struct ahd_softc *ahd; int found; + unsigned long flags; ahd = *(struct ahd_softc **)cmd->device->host->hostdata; #ifdef AHD_DEBUG @@ -789,8 +790,11 @@ ahd_linux_bus_reset(struct scsi_cmnd *cmd) printf("%s: Bus reset called for cmd %p\n", ahd_name(ahd), cmd); #endif + ahd_lock(ahd, &flags); + found = ahd_reset_channel(ahd, scmd_channel(cmd) + 'A', /*initiate reset*/TRUE); + ahd_unlock(ahd, &flags); if (bootverbose) printf("%s: SCSI bus reset delivered. 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