Defined SCSI device interface, and added SCSI block device

implementation.

2 files changed, 279 insertions, 7 deletions

diff --git a/src/drivers/block/scsi.c b/src/drivers/block/scsi.c
new file mode 100644
index 00000000..7ddc4a11
--- /dev/null
+++ b/src/drivers/block/scsi.c
@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stddef.h>
+#include <string.h>
+#include <byteswap.h>
+#include <gpxe/blockdev.h>
+#include <gpxe/scsi.h>
+
+/** @file
+ *
+ * SCSI block device
+ *
+ */
+
+static inline __attribute__ (( always_inline )) struct scsi_device *
+block_to_scsi ( struct block_device *blockdev ) {
+	return container_of ( blockdev, struct scsi_device, blockdev );
+}
+
+/**
+ * Issue SCSI command
+ *
+ * @v scsi		SCSI device
+ * @v command		SCSI command
+ * @ret rc		Return status code
+ */
+static int scsi_command ( struct scsi_device *scsi,
+			  struct scsi_command *command ) {
+	return scsi->command ( scsi, command );
+}
+
+/**
+ * Read block from SCSI device
+ *
+ * @v blockdev		Block device
+ * @v block		LBA block number
+ * @v buffer		Data buffer
+ * @ret rc		Return status code
+ */
+static int scsi_read ( struct block_device *blockdev, uint64_t block,
+		       void *buffer ) {
+	struct scsi_device *scsi = block_to_scsi ( blockdev );
+	struct scsi_command command;
+	struct scsi_cdb_read_16 *cdb = &command.cdb.read16;
+
+	/* Issue READ (16) */
+	memset ( &command, 0, sizeof ( command ) );
+	cdb->opcode = SCSI_OPCODE_READ_16;
+	cdb->lba = cpu_to_be64 ( block );
+	cdb->len = cpu_to_be32 ( 1 ); /* always a single block */
+	command.data_in = buffer;
+	command.data_in_len = blockdev->blksize;
+	return scsi_command ( scsi, &command );
+}
+
+/**
+ * Write block to SCSI device
+ *
+ * @v blockdev		Block device
+ * @v block		LBA block number
+ * @v buffer		Data buffer
+ * @ret rc		Return status code
+ */
+static int scsi_write ( struct block_device *blockdev, uint64_t block,
+			const void *buffer ) {
+	struct scsi_device *scsi = block_to_scsi ( blockdev );
+	struct scsi_command command;
+	struct scsi_cdb_write_16 *cdb = &command.cdb.write16;
+
+	/* Issue WRITE (16) */
+	memset ( &command, 0, sizeof ( command ) );
+	cdb->opcode = SCSI_OPCODE_WRITE_16;
+	cdb->lba = cpu_to_be64 ( block );
+	cdb->len = cpu_to_be32 ( 1 ); /* always a single block */
+	command.data_out = buffer;
+	command.data_out_len = blockdev->blksize;
+	return scsi_command ( scsi, &command );
+}
+
+/**
+ * Read capacity of SCSI device
+ *
+ * @v blockdev		Block device
+ * @ret rc		Return status code
+ */
+static int scsi_read_capacity ( struct block_device *blockdev ) {
+	struct scsi_device *scsi = block_to_scsi ( blockdev );
+	struct scsi_command command;
+	struct scsi_cdb_read_capacity_16 *cdb = &command.cdb.readcap16;
+	struct scsi_capacity_16 capacity;
+	int rc;
+
+	/* Issue READ CAPACITY (16) */
+	memset ( &command, 0, sizeof ( command ) );
+	cdb->opcode = SCSI_OPCODE_SERVICE_ACTION_IN;
+	cdb->service_action = SCSI_SERVICE_ACTION_READ_CAPACITY_16;
+	cdb->len = cpu_to_be32 ( sizeof ( capacity ) );
+	command.data_in = &capacity;
+	command.data_in_len = sizeof ( capacity );
+
+	if ( ( rc = scsi_command ( scsi, &command ) ) != 0 )
+		return rc;
+
+	/* Fill in block device fields */
+	blockdev->blksize = be32_to_cpu ( capacity.blksize );
+	blockdev->blocks = ( be64_to_cpu ( capacity.lba ) + 1 );
+	return 0;
+}
+
+/**
+ * Initialise SCSI device
+ *
+ * @v scsi		SCSI device
+ * @ret rc		Return status code
+ *
+ * Initialises a SCSI device.  The scsi_device::command and
+ * scsi_device::lun fields must already be filled in.  This function
+ * will configure scsi_device::blockdev, including issuing a READ
+ * CAPACITY call to determine the block size and total device size.
+ */
+int init_scsidev ( struct scsi_device *scsi ) {
+	/** Fill in read and write methods, and get device capacity */
+	scsi->blockdev.read = scsi_read;
+	scsi->blockdev.write = scsi_write;
+	return scsi_read_capacity ( &scsi->blockdev );
+}
diff --git a/src/include/gpxe/scsi.h b/src/include/gpxe/scsi.h
index be71bab3..db57e891 100644
--- a/src/include/gpxe/scsi.h
+++ b/src/include/gpxe/scsi.h
@@ -2,9 +2,61 @@
 #define _GPXE_SCSI_H
 
 #include <stdint.h>
+#include <gpxe/blockdev.h>
 
-struct scsi_cdb_read_10 {
-	/** Opcode */
+/**
+ * @defgroup scsiops SCSI operation codes
+ * @{
+ */
+
+#define SCSI_OPCODE_READ_16		0x88	/**< READ (16) */
+#define SCSI_OPCODE_WRITE_16		0x8a	/**< WRITE (16) */
+#define SCSI_OPCODE_SERVICE_ACTION_IN	0x9e	/**< SERVICE ACTION IN */
+#define SCSI_SERVICE_ACTION_READ_CAPACITY_16 0x10 /**< READ CAPACITY (16) */
+
+/** @} */
+
+/**
+ * @defgroup scsiflags SCSI flags
+ * @{
+ */
+
+#define SCSI_FL_FUA_NV		0x02	/**< Force unit access to NVS */
+#define SCSI_FL_FUA		0x08	/**< Force unit access */
+#define SCSI_FL_DPO		0x10	/**< Disable cache page out */
+
+/** @} */
+
+/**
+ * @defgroup scsicdbs SCSI command data blocks
+ * @{
+ */
+
+/** A SCSI "READ (16)" CDB */
+struct scsi_cdb_read_16 {
+	/** Opcode (0x88) */
+	uint8_t opcode;
+	/** Flags */
+	uint8_t flags;
+	/** Start address
+	 *
+	 * This is a logical block number, in big-endian order.
+	 */
+	uint64_t lba;
+	/** Transfer length
+	 *
+	 * This is a logical block count, in big-endian order.
+	 */
+	uint32_t len;
+	/** Group number */
+	uint8_t group;
+	/** Control byte */
+	uint8_t control;
+} __attribute__ (( packed ));
+
+/** A SCSI "WRITE (16)" CDB */
+struct scsi_cdb_write_16 {
+	/** Opcode (0x8a) */
 	uint8_t opcode;
 	/** Flags */
 	uint8_t flags;
@@ -12,23 +64,101 @@ struct scsi_cdb_read_10 {
 	 *
 	 * This is a logical block number, in big-endian order.
 	 */
-	uint32_t lba;
+	uint64_t lba;
+	/** Transfer length
+	 *
+	 * This is a logical block count, in big-endian order.
+	 */
+	uint32_t len;
 	/** Group number */
 	uint8_t group;
+	/** Control byte */
+	uint8_t control;
+} __attribute__ (( packed ));
+
+/** A SCSI "READ CAPACITY (16)" CDB */
+struct scsi_cdb_read_capacity_16 {
+	/** Opcode (0x9e) */
+	uint8_t opcode;
+	/** Service action */
+	uint8_t service_action;
+	/** Logical block address
+	 *
+	 * Applicable only if the PMI bit is set.
+	 */
+	uint64_t lba;
 	/** Transfer length
 	 *
-	 * This is a logical block count.
+	 * This is the size of the data-in buffer, in bytes.
 	 */
-	uint16_t len;
+	uint32_t len;
+	/** Reserved */
+	uint8_t reserved;
 	/** Control byte */
 	uint8_t control;
 } __attribute__ (( packed ));
 
-#define SCSI_OPCODE_READ_10 0x28
+/** SCSI "READ CAPACITY (16)" parameter data */
+struct scsi_capacity_16 {
+	/** Maximum logical block number */
+	uint64_t lba;
+	/** Block length in bytes */
+	uint32_t blksize;
+	/** Reserved */
+	uint8_t reserved[20];
+} __attribute__ (( packed ));
 
+/** A SCSI Command Data Block */
 union scsi_cdb {
-	struct scsi_cdb_read_10 read_10;
+	struct scsi_cdb_read_16 read16;
+	struct scsi_cdb_write_16 write16;
+	struct scsi_cdb_read_capacity_16 readcap16;
 	char bytes[16];
 };
 
+/** @} */
+
+/** A SCSI command */
+struct scsi_command {
+	/** CDB for this command */
+	union scsi_cdb cdb;
+	/** Data-out buffer (may be NULL) */
+	const void *data_out;
+	/** Data-out buffer length
+	 *
+	 * Must be zero if @c data_out is NULL
+	 */
+	size_t data_out_len;
+	/** Data-in buffer (may be NULL) */
+	void *data_in;
+	/** Data-in buffer length
+	 *
+	 * Must be zero if @c data_in is NULL
+	 */
+	size_t data_in_len;
+};
+
+/** A SCSI device */
+struct scsi_device {
+	/** Block device interface */
+	struct block_device blockdev;
+	/** Logical unit number (LUN)
+	 *
+	 * This is a four-level LUN as specified by SAM-2, in
+	 * big-endian order.
+	 */
+	uint64_t lun;
+	/**
+	 * Issue SCSI command
+	 *
+	 * @v scsi		SCSI device
+	 * @v command		SCSI command
+	 * @ret rc		Return status code
+	 */
+	int ( * command ) ( struct scsi_device *scsi,
+			    struct scsi_command *command );
+};
+
+extern int init_scsidev ( struct scsi_device *scsi );
+
 #endif /* _GPXE_SCSI_H */