drivers/ata/sata_promise.h

Source file repositories/reference/linux-study-clean/drivers/ata/sata_promise.h

File Facts

System
Linux kernel
Corpus path
drivers/ata/sata_promise.h
Extension
.h
Size
3138 bytes
Lines
142
Domain
Driver Families
Bucket
drivers/ata
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __SATA_PROMISE_H__
#define __SATA_PROMISE_H__

#include <linux/ata.h>

enum pdc_packet_bits {
	PDC_PKT_READ		= (1 << 2),
	PDC_PKT_NODATA		= (1 << 3),

	PDC_PKT_SIZEMASK	= (1 << 7) | (1 << 6) | (1 << 5),
	PDC_PKT_CLEAR_BSY	= (1 << 4),
	PDC_PKT_WAIT_DRDY	= (1 << 3) | (1 << 4),
	PDC_LAST_REG		= (1 << 3),

	PDC_REG_DEVCTL		= (1 << 3) | (1 << 2) | (1 << 1),
};

static inline unsigned int pdc_pkt_header(struct ata_taskfile *tf,
					  dma_addr_t sg_table,
					  unsigned int devno, u8 *buf)
{
	u8 dev_reg;
	__le32 *buf32 = (__le32 *) buf;

	/* set control bits (byte 0), zero delay seq id (byte 3),
	 * and seq id (byte 2)
	 */
	switch (tf->protocol) {
	case ATA_PROT_DMA:
		if (!(tf->flags & ATA_TFLAG_WRITE))
			buf32[0] = cpu_to_le32(PDC_PKT_READ);
		else
			buf32[0] = 0;
		break;

	case ATA_PROT_NODATA:
		buf32[0] = cpu_to_le32(PDC_PKT_NODATA);
		break;

	default:
		BUG();
		break;
	}

	buf32[1] = cpu_to_le32(sg_table);	/* S/G table addr */
	buf32[2] = 0;				/* no next-packet */

	if (devno == 0)
		dev_reg = ATA_DEVICE_OBS;
	else
		dev_reg = ATA_DEVICE_OBS | ATA_DEV1;

	/* select device */
	buf[12] = (1 << 5) | PDC_PKT_CLEAR_BSY | ATA_REG_DEVICE;
	buf[13] = dev_reg;

	/* device control register */
	buf[14] = (1 << 5) | PDC_REG_DEVCTL;
	buf[15] = tf->ctl;

	return 16; 	/* offset of next byte */
}

static inline unsigned int pdc_pkt_footer(struct ata_taskfile *tf, u8 *buf,
				  unsigned int i)
{
	if (tf->flags & ATA_TFLAG_DEVICE) {
		buf[i++] = (1 << 5) | ATA_REG_DEVICE;
		buf[i++] = tf->device;
	}

	/* and finally the command itself; also includes end-of-pkt marker */
	buf[i++] = (1 << 5) | PDC_LAST_REG | ATA_REG_CMD;
	buf[i++] = tf->command;

	return i;
}

static inline unsigned int pdc_prep_lba28(struct ata_taskfile *tf, u8 *buf, unsigned int i)
{
	/* the "(1 << 5)" should be read "(count << 5)" */

	/* ATA command block registers */
	buf[i++] = (1 << 5) | ATA_REG_FEATURE;
	buf[i++] = tf->feature;

	buf[i++] = (1 << 5) | ATA_REG_NSECT;
	buf[i++] = tf->nsect;

	buf[i++] = (1 << 5) | ATA_REG_LBAL;

Annotation

Implementation Notes