From a6d5a51cf1bf5d83ddd2e06fd372a79b395fb393 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 6 Mar 2006 04:31:57 +0900 Subject: [PATCH] [PATCH] libata: reimplement ata_set_mode() using xfer_mask helpers Use xfer_mask helpers to determine transfer mode. This rewrite also makes transfer mode determination done before any actual configuration. This patch doesn't result in any functional changes. Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/scsi/libata-core.c | 233 +++++++++++++------------------------ 1 file changed, 79 insertions(+), 154 deletions(-) diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 88495127efb2..d211f0b1d721 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -65,11 +65,9 @@ static unsigned int ata_dev_init_params(struct ata_port *ap, struct ata_device *dev); static void ata_set_mode(struct ata_port *ap); static void ata_dev_set_xfermode(struct ata_port *ap, struct ata_device *dev); -static unsigned int ata_get_mode_mask(const struct ata_port *ap, int shift); +static unsigned int ata_dev_xfermask(struct ata_port *ap, + struct ata_device *dev); static int fgb(u32 bitmap); -static int ata_choose_xfer_mode(const struct ata_port *ap, - u8 *xfer_mode_out, - unsigned int *xfer_shift_out); static unsigned int ata_unique_id = 1; static struct workqueue_struct *ata_wq; @@ -1776,51 +1774,42 @@ static void ata_dev_set_mode(struct ata_port *ap, struct ata_device *dev) static int ata_host_set_pio(struct ata_port *ap) { - unsigned int mask; - int x, i; - u8 base, xfer_mode; - - mask = ata_get_mode_mask(ap, ATA_SHIFT_PIO); - x = fgb(mask); - if (x < 0) { - printk(KERN_WARNING "ata%u: no PIO support\n", ap->id); - return -1; - } - - base = base_from_shift(ATA_SHIFT_PIO); - xfer_mode = base + x; - - DPRINTK("base 0x%x xfer_mode 0x%x mask 0x%x x %d\n", - (int)base, (int)xfer_mode, mask, x); + int i; for (i = 0; i < ATA_MAX_DEVICES; i++) { struct ata_device *dev = &ap->device[i]; - if (ata_dev_present(dev)) { - dev->pio_mode = xfer_mode; - dev->xfer_mode = xfer_mode; - dev->xfer_shift = ATA_SHIFT_PIO; - if (ap->ops->set_piomode) - ap->ops->set_piomode(ap, dev); + + if (!ata_dev_present(dev)) + continue; + + if (!dev->pio_mode) { + printk(KERN_WARNING "ata%u: no PIO support\n", ap->id); + return -1; } + + dev->xfer_mode = dev->pio_mode; + dev->xfer_shift = ATA_SHIFT_PIO; + if (ap->ops->set_piomode) + ap->ops->set_piomode(ap, dev); } return 0; } -static void ata_host_set_dma(struct ata_port *ap, u8 xfer_mode, - unsigned int xfer_shift) +static void ata_host_set_dma(struct ata_port *ap) { int i; for (i = 0; i < ATA_MAX_DEVICES; i++) { struct ata_device *dev = &ap->device[i]; - if (ata_dev_present(dev)) { - dev->dma_mode = xfer_mode; - dev->xfer_mode = xfer_mode; - dev->xfer_shift = xfer_shift; - if (ap->ops->set_dmamode) - ap->ops->set_dmamode(ap, dev); - } + + if (!ata_dev_present(dev) || !dev->dma_mode) + continue; + + dev->xfer_mode = dev->dma_mode; + dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode); + if (ap->ops->set_dmamode) + ap->ops->set_dmamode(ap, dev); } } @@ -1835,28 +1824,34 @@ static void ata_host_set_dma(struct ata_port *ap, u8 xfer_mode, */ static void ata_set_mode(struct ata_port *ap) { - unsigned int xfer_shift; - u8 xfer_mode; - int rc; + int i, rc; - /* step 1: always set host PIO timings */ + /* step 1: calculate xfer_mask */ + for (i = 0; i < ATA_MAX_DEVICES; i++) { + struct ata_device *dev = &ap->device[i]; + unsigned int xfer_mask; + + if (!ata_dev_present(dev)) + continue; + + xfer_mask = ata_dev_xfermask(ap, dev); + + dev->pio_mode = ata_xfer_mask2mode(xfer_mask & ATA_MASK_PIO); + dev->dma_mode = ata_xfer_mask2mode(xfer_mask & (ATA_MASK_MWDMA | + ATA_MASK_UDMA)); + } + + /* step 2: always set host PIO timings */ rc = ata_host_set_pio(ap); if (rc) goto err_out; - /* step 2: choose the best data xfer mode */ - xfer_mode = xfer_shift = 0; - rc = ata_choose_xfer_mode(ap, &xfer_mode, &xfer_shift); - if (rc) - goto err_out; - - /* step 3: if that xfer mode isn't PIO, set host DMA timings */ - if (xfer_shift != ATA_SHIFT_PIO) - ata_host_set_dma(ap, xfer_mode, xfer_shift); + /* step 3: set host DMA timings */ + ata_host_set_dma(ap); /* step 4: update devices' xfer mode */ - ata_dev_set_mode(ap, &ap->device[0]); - ata_dev_set_mode(ap, &ap->device[1]); + for (i = 0; i < ATA_MAX_DEVICES; i++) + ata_dev_set_mode(ap, &ap->device[i]); if (ap->flags & ATA_FLAG_PORT_DISABLED) return; @@ -2654,77 +2649,45 @@ static int ata_dma_blacklisted(const struct ata_device *dev) return 0; } -static unsigned int ata_get_mode_mask(const struct ata_port *ap, int shift) +/** + * ata_dev_xfermask - Compute supported xfermask of the given device + * @ap: Port on which the device to compute xfermask for resides + * @dev: Device to compute xfermask for + * + * Compute supported xfermask of @dev. This function is + * responsible for applying all known limits including host + * controller limits, device blacklist, etc... + * + * LOCKING: + * None. + * + * RETURNS: + * Computed xfermask. + */ +static unsigned int ata_dev_xfermask(struct ata_port *ap, + struct ata_device *dev) { - const struct ata_device *master, *slave; - unsigned int mask; + unsigned long xfer_mask; + int i; - master = &ap->device[0]; - slave = &ap->device[1]; + xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask, + ap->udma_mask); - WARN_ON(!ata_dev_present(master) && !ata_dev_present(slave)); - - if (shift == ATA_SHIFT_UDMA) { - mask = ap->udma_mask; - if (ata_dev_present(master)) { - mask &= (master->id[ATA_ID_UDMA_MODES] & 0xff); - if (ata_dma_blacklisted(master)) { - mask = 0; - ata_pr_blacklisted(ap, master); - } - } - if (ata_dev_present(slave)) { - mask &= (slave->id[ATA_ID_UDMA_MODES] & 0xff); - if (ata_dma_blacklisted(slave)) { - mask = 0; - ata_pr_blacklisted(ap, slave); - } - } - } - else if (shift == ATA_SHIFT_MWDMA) { - mask = ap->mwdma_mask; - if (ata_dev_present(master)) { - mask &= (master->id[ATA_ID_MWDMA_MODES] & 0x07); - if (ata_dma_blacklisted(master)) { - mask = 0; - ata_pr_blacklisted(ap, master); - } - } - if (ata_dev_present(slave)) { - mask &= (slave->id[ATA_ID_MWDMA_MODES] & 0x07); - if (ata_dma_blacklisted(slave)) { - mask = 0; - ata_pr_blacklisted(ap, slave); - } - } - } - else if (shift == ATA_SHIFT_PIO) { - mask = ap->pio_mask; - if (ata_dev_present(master)) { - /* spec doesn't return explicit support for - * PIO0-2, so we fake it - */ - u16 tmp_mode = master->id[ATA_ID_PIO_MODES] & 0x03; - tmp_mode <<= 3; - tmp_mode |= 0x7; - mask &= tmp_mode; - } - if (ata_dev_present(slave)) { - /* spec doesn't return explicit support for - * PIO0-2, so we fake it - */ - u16 tmp_mode = slave->id[ATA_ID_PIO_MODES] & 0x03; - tmp_mode <<= 3; - tmp_mode |= 0x7; - mask &= tmp_mode; - } - } - else { - mask = 0xffffffff; /* shut up compiler warning */ - BUG(); + /* use port-wide xfermask for now */ + for (i = 0; i < ATA_MAX_DEVICES; i++) { + struct ata_device *d = &ap->device[i]; + if (!ata_dev_present(d)) + continue; + xfer_mask &= ata_id_xfermask(d->id); + if (ata_dma_blacklisted(d)) + xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA); } - return mask; + if (ata_dma_blacklisted(dev)) + printk(KERN_WARNING "ata%u: dev %u is on DMA blacklist, " + "disabling DMA\n", ap->id, dev->devno); + + return xfer_mask; } /* find greatest bit */ @@ -2740,44 +2703,6 @@ static int fgb(u32 bitmap) return x; } -/** - * ata_choose_xfer_mode - attempt to find best transfer mode - * @ap: Port for which an xfer mode will be selected - * @xfer_mode_out: (output) SET FEATURES - XFER MODE code - * @xfer_shift_out: (output) bit shift that selects this mode - * - * Based on host and device capabilities, determine the - * maximum transfer mode that is amenable to all. - * - * LOCKING: - * PCI/etc. bus probe sem. - * - * RETURNS: - * Zero on success, negative on error. - */ - -static int ata_choose_xfer_mode(const struct ata_port *ap, - u8 *xfer_mode_out, - unsigned int *xfer_shift_out) -{ - unsigned int mask, shift; - int x, i; - - for (i = 0; i < ARRAY_SIZE(xfer_mode_classes); i++) { - shift = xfer_mode_classes[i].shift; - mask = ata_get_mode_mask(ap, shift); - - x = fgb(mask); - if (x >= 0) { - *xfer_mode_out = xfer_mode_classes[i].base + x; - *xfer_shift_out = shift; - return 0; - } - } - - return -1; -} - /** * ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command * @ap: Port associated with device @dev