diff options
| -rw-r--r-- | drivers/scsi/libata-core.c | 139 |
1 files changed, 133 insertions, 6 deletions
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 6e56af23957..3544f5d020c 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -2519,6 +2519,20 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words) #endif /* __BIG_ENDIAN */ } +/** + * ata_mmio_data_xfer - Transfer data by MMIO + * @ap: port to read/write + * @buf: data buffer + * @buflen: buffer length + * @do_write: read/write + * + * Transfer data from/to the device data register by MMIO. + * + * LOCKING: + * Inherited from caller. + * + */ + static void ata_mmio_data_xfer(struct ata_port *ap, unsigned char *buf, unsigned int buflen, int write_data) { @@ -2527,6 +2541,7 @@ static void ata_mmio_data_xfer(struct ata_port *ap, unsigned char *buf, u16 *buf16 = (u16 *) buf; void __iomem *mmio = (void __iomem *)ap->ioaddr.data_addr; + /* Transfer multiple of 2 bytes */ if (write_data) { for (i = 0; i < words; i++) writew(le16_to_cpu(buf16[i]), mmio); @@ -2534,19 +2549,76 @@ static void ata_mmio_data_xfer(struct ata_port *ap, unsigned char *buf, for (i = 0; i < words; i++) buf16[i] = cpu_to_le16(readw(mmio)); } + + /* Transfer trailing 1 byte, if any. */ + if (unlikely(buflen & 0x01)) { + u16 align_buf[1] = { 0 }; + unsigned char *trailing_buf = buf + buflen - 1; + + if (write_data) { + memcpy(align_buf, trailing_buf, 1); + writew(le16_to_cpu(align_buf[0]), mmio); + } else { + align_buf[0] = cpu_to_le16(readw(mmio)); + memcpy(trailing_buf, align_buf, 1); + } + } } +/** + * ata_pio_data_xfer - Transfer data by PIO + * @ap: port to read/write + * @buf: data buffer + * @buflen: buffer length + * @do_write: read/write + * + * Transfer data from/to the device data register by PIO. + * + * LOCKING: + * Inherited from caller. + * + */ + static void ata_pio_data_xfer(struct ata_port *ap, unsigned char *buf, unsigned int buflen, int write_data) { - unsigned int dwords = buflen >> 1; + unsigned int words = buflen >> 1; + /* Transfer multiple of 2 bytes */ if (write_data) - outsw(ap->ioaddr.data_addr, buf, dwords); + outsw(ap->ioaddr.data_addr, buf, words); else - insw(ap->ioaddr.data_addr, buf, dwords); + insw(ap->ioaddr.data_addr, buf, words); + + /* Transfer trailing 1 byte, if any. */ + if (unlikely(buflen & 0x01)) { + u16 align_buf[1] = { 0 }; + unsigned char *trailing_buf = buf + buflen - 1; + + if (write_data) { + memcpy(align_buf, trailing_buf, 1); + outw(le16_to_cpu(align_buf[0]), ap->ioaddr.data_addr); + } else { + align_buf[0] = cpu_to_le16(inw(ap->ioaddr.data_addr)); + memcpy(trailing_buf, align_buf, 1); + } + } } +/** + * ata_data_xfer - Transfer data from/to the data register. + * @ap: port to read/write + * @buf: data buffer + * @buflen: buffer length + * @do_write: read/write + * + * Transfer data from/to the device data register. + * + * LOCKING: + * Inherited from caller. + * + */ + static void ata_data_xfer(struct ata_port *ap, unsigned char *buf, unsigned int buflen, int do_write) { @@ -2556,6 +2628,16 @@ static void ata_data_xfer(struct ata_port *ap, unsigned char *buf, ata_pio_data_xfer(ap, buf, buflen, do_write); } +/** + * ata_pio_sector - Transfer ATA_SECT_SIZE (512 bytes) of data. + * @qc: Command on going + * + * Transfer ATA_SECT_SIZE of data from/to the ATA device. + * + * LOCKING: + * Inherited from caller. + */ + static void ata_pio_sector(struct ata_queued_cmd *qc) { int do_write = (qc->tf.flags & ATA_TFLAG_WRITE); @@ -2594,6 +2676,18 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) kunmap(page); } +/** + * __atapi_pio_bytes - Transfer data from/to the ATAPI device. + * @qc: Command on going + * @bytes: number of bytes + * + * Transfer Transfer data from/to the ATAPI device. + * + * LOCKING: + * Inherited from caller. + * + */ + static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) { int do_write = (qc->tf.flags & ATA_TFLAG_WRITE); @@ -2603,10 +2697,33 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) unsigned char *buf; unsigned int offset, count; - if (qc->curbytes == qc->nbytes - bytes) + if (qc->curbytes + bytes >= qc->nbytes) ap->pio_task_state = PIO_ST_LAST; next_sg: + if (unlikely(qc->cursg >= qc->n_elem)) { + /* + * The end of qc->sg is reached and the device expects + * more data to transfer. In order not to overrun qc->sg + * and fulfill length specified in the byte count register, + * - for read case, discard trailing data from the device + * - for write case, padding zero data to the device + */ + u16 pad_buf[1] = { 0 }; + unsigned int words = bytes >> 1; + unsigned int i; + + if (words) /* warning if bytes > 1 */ + printk(KERN_WARNING "ata%u: %u bytes trailing data\n", + ap->id, bytes); + + for (i = 0; i < words; i++) + ata_data_xfer(ap, (unsigned char*)pad_buf, 2, do_write); + + ap->pio_task_state = PIO_ST_LAST; + return; + } + sg = &qc->sg[qc->cursg]; page = sg->page; @@ -2640,11 +2757,21 @@ next_sg: kunmap(page); - if (bytes) { + if (bytes) goto next_sg; - } } +/** + * atapi_pio_bytes - Transfer data from/to the ATAPI device. + * @qc: Command on going + * + * Transfer Transfer data from/to the ATAPI device. + * + * LOCKING: + * Inherited from caller. + * + */ + static void atapi_pio_bytes(struct ata_queued_cmd *qc) { struct ata_port *ap = qc->ap; |