diff options
Diffstat (limited to 'drivers/ide/pci/it821x.c')
| -rw-r--r-- | drivers/ide/pci/it821x.c | 126 |
1 files changed, 58 insertions, 68 deletions
diff --git a/drivers/ide/pci/it821x.c b/drivers/ide/pci/it821x.c index a132767f7d90..4e1254813ee0 100644 --- a/drivers/ide/pci/it821x.c +++ b/drivers/ide/pci/it821x.c @@ -1,8 +1,9 @@ /* - * linux/drivers/ide/pci/it821x.c Version 0.09 December 2004 + * linux/drivers/ide/pci/it821x.c Version 0.10 Mar 10 2007 * * Copyright (C) 2004 Red Hat <alan@redhat.com> + * Copyright (C) 2007 Bartlomiej Zolnierkiewicz * * May be copied or modified under the terms of the GNU General Public License * Based in part on the ITE vendor provided SCSI driver. @@ -104,6 +105,7 @@ static int it8212_noraid; /** * it821x_program - program the PIO/MWDMA registers * @drive: drive to tune + * @timing: timing info * * Program the PIO/MWDMA timing for this channel according to the * current clock. @@ -127,6 +129,7 @@ static void it821x_program(ide_drive_t *drive, u16 timing) /** * it821x_program_udma - program the UDMA registers * @drive: drive to tune + * @timing: timing info * * Program the UDMA timing for this drive according to the * current clock. @@ -153,10 +156,9 @@ static void it821x_program_udma(ide_drive_t *drive, u16 timing) } } - /** * it821x_clock_strategy - * @hwif: hardware interface + * @drive: drive to set up * * Select between the 50 and 66Mhz base clocks to get the best * results for this interface. @@ -182,8 +184,11 @@ static void it821x_clock_strategy(ide_drive_t *drive) altclock = itdev->want[0][1]; } - /* Master doesn't care does the slave ? */ - if(clock == ATA_ANY) + /* + * if both clocks can be used for the mode with the higher priority + * use the clock needed by the mode with the lower priority + */ + if (clock == ATA_ANY) clock = altclock; /* Nobody cares - keep the same clock */ @@ -240,37 +245,56 @@ static u8 it821x_ratemask (ide_drive_t *drive) } /** - * it821x_tuneproc - tune a drive + * it821x_tunepio - tune a drive * @drive: drive to tune - * @mode_wanted: the target operating mode - * - * Load the timing settings for this device mode into the - * controller. By the time we are called the mode has been - * modified as neccessary to handle the absence of seperate - * master/slave timers for MWDMA/PIO. + * @pio: the desired PIO mode * - * This code is only used in pass through mode. + * Try to tune the drive/host to the desired PIO mode taking into + * the consideration the maximum PIO mode supported by the other + * device on the cable. */ -static void it821x_tuneproc (ide_drive_t *drive, byte mode_wanted) +static int it821x_tunepio(ide_drive_t *drive, u8 set_pio) { ide_hwif_t *hwif = drive->hwif; struct it821x_dev *itdev = ide_get_hwifdata(hwif); int unit = drive->select.b.unit; + ide_drive_t *pair = &hwif->drives[1 - unit]; /* Spec says 89 ref driver uses 88 */ static u16 pio[] = { 0xAA88, 0xA382, 0xA181, 0x3332, 0x3121 }; static u8 pio_want[] = { ATA_66, ATA_66, ATA_66, ATA_66, ATA_ANY }; - if(itdev->smart) - return; + /* + * Compute the best PIO mode we can for a given device. We must + * pick a speed that does not cause problems with the other device + * on the cable. + */ + if (pair) { + u8 pair_pio = ide_get_best_pio_mode(pair, 255, 4, NULL); + /* trim PIO to the slowest of the master/slave */ + if (pair_pio < set_pio) + set_pio = pair_pio; + } + + if (itdev->smart) + goto set_drive_speed; /* We prefer 66Mhz clock for PIO 0-3, don't care for PIO4 */ - itdev->want[unit][1] = pio_want[mode_wanted]; + itdev->want[unit][1] = pio_want[set_pio]; itdev->want[unit][0] = 1; /* PIO is lowest priority */ - itdev->pio[unit] = pio[mode_wanted]; + itdev->pio[unit] = pio[set_pio]; it821x_clock_strategy(drive); it821x_program(drive, itdev->pio[unit]); + +set_drive_speed: + return ide_config_drive_speed(drive, XFER_PIO_0 + set_pio); +} + +static void it821x_tuneproc(ide_drive_t *drive, u8 pio) +{ + pio = ide_get_best_pio_mode(drive, pio, 4, NULL); + (void)it821x_tunepio(drive, pio); } /** @@ -354,40 +378,6 @@ static void it821x_tune_udma (ide_drive_t *drive, byte mode_wanted) } /** - * config_it821x_chipset_for_pio - set drive timings - * @drive: drive to tune - * @speed we want - * - * Compute the best pio mode we can for a given device. We must - * pick a speed that does not cause problems with the other device - * on the cable. - */ - -static void config_it821x_chipset_for_pio (ide_drive_t *drive, byte set_speed) -{ - u8 unit = drive->select.b.unit; - ide_hwif_t *hwif = drive->hwif; - ide_drive_t *pair = &hwif->drives[1-unit]; - u8 speed = 0, set_pio = ide_get_best_pio_mode(drive, 255, 5, NULL); - u8 pair_pio; - - /* We have to deal with this mess in pairs */ - if(pair != NULL) { - pair_pio = ide_get_best_pio_mode(pair, 255, 5, NULL); - /* Trim PIO to the slowest of the master/slave */ - if(pair_pio < set_pio) - set_pio = pair_pio; - } - it821x_tuneproc(drive, set_pio); - speed = XFER_PIO_0 + set_pio; - /* XXX - We trim to the lowest of the pair so the other drive - will always be fine at this point until we do hotplug passthru */ - - if (set_speed) - (void) ide_config_drive_speed(drive, speed); -} - -/** * it821x_dma_read - DMA hook * @drive: drive for DMA * @@ -450,15 +440,17 @@ static int it821x_tune_chipset (ide_drive_t *drive, byte xferspeed) struct it821x_dev *itdev = ide_get_hwifdata(hwif); u8 speed = ide_rate_filter(it821x_ratemask(drive), xferspeed); - if(!itdev->smart) { - switch(speed) { - case XFER_PIO_4: - case XFER_PIO_3: - case XFER_PIO_2: - case XFER_PIO_1: - case XFER_PIO_0: - it821x_tuneproc(drive, (speed - XFER_PIO_0)); - break; + switch (speed) { + case XFER_PIO_4: + case XFER_PIO_3: + case XFER_PIO_2: + case XFER_PIO_1: + case XFER_PIO_0: + return it821x_tunepio(drive, speed - XFER_PIO_0); + } + + if (itdev->smart == 0) { + switch (speed) { /* MWDMA tuning is really hard because our MWDMA and PIO timings are kept in the same place. We can switch in the host dma on/off callbacks */ @@ -498,14 +490,12 @@ static int config_chipset_for_dma (ide_drive_t *drive) { u8 speed = ide_dma_speed(drive, it821x_ratemask(drive)); - if (speed) { - config_it821x_chipset_for_pio(drive, 0); - it821x_tune_chipset(drive, speed); + if (speed == 0) + return 0; - return ide_dma_enable(drive); - } + it821x_tune_chipset(drive, speed); - return 0; + return ide_dma_enable(drive); } /** @@ -523,7 +513,7 @@ static int it821x_config_drive_for_dma (ide_drive_t *drive) if (ide_use_dma(drive) && config_chipset_for_dma(drive)) return 0; - config_it821x_chipset_for_pio(drive, 1); + it821x_tuneproc(drive, 255); return -1; } |