ps3: BD/DVD/CD-ROM Storage Driver

Add a BD/DVD/CD-ROM Storage Driver for the PS3:
  - Implemented as a SCSI device driver
  - Uses software scatter-gather with a 64 KiB bounce buffer as the hypervisor
    doesn't support scatter-gather

Cc: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 534 insertions, 0 deletions

diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 0f868955715..86a7ba7bad6 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -132,6 +132,7 @@ obj-$(CONFIG_SCSI_IBMVSCSI)	+= ibmvscsi/
 obj-$(CONFIG_SCSI_IBMVSCSIS)	+= ibmvscsi/
 obj-$(CONFIG_SCSI_HPTIOP)	+= hptiop.o
 obj-$(CONFIG_SCSI_STEX)		+= stex.o
+obj-$(CONFIG_PS3_ROM)		+= ps3rom.o
 
 obj-$(CONFIG_ARM)		+= arm/
 
diff --git a/drivers/scsi/ps3rom.c b/drivers/scsi/ps3rom.c
new file mode 100644
index 00000000000..b50f1e14f2a
--- /dev/null
+++ b/drivers/scsi/ps3rom.c
@@ -0,0 +1,533 @@
+/*
+ * PS3 BD/DVD/CD-ROM Storage Driver
+ *
+ * Copyright (C) 2007 Sony Computer Entertainment Inc.
+ * Copyright 2007 Sony Corp.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/cdrom.h>
+#include <linux/highmem.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+
+#include <asm/lv1call.h>
+#include <asm/ps3stor.h>
+
+
+#define DEVICE_NAME			"ps3rom"
+
+#define BOUNCE_SIZE			(64*1024)
+
+#define PS3ROM_MAX_SECTORS		(BOUNCE_SIZE / CD_FRAMESIZE)
+
+
+struct ps3rom_private {
+	struct ps3_storage_device *dev;
+	struct scsi_cmnd *curr_cmd;
+};
+
+
+#define LV1_STORAGE_SEND_ATAPI_COMMAND	(1)
+
+struct lv1_atapi_cmnd_block {
+	u8	pkt[32];	/* packet command block           */
+	u32	pktlen;		/* should be 12 for ATAPI 8020    */
+	u32	blocks;
+	u32	block_size;
+	u32	proto;		/* transfer mode                  */
+	u32	in_out;		/* transfer direction             */
+	u64	buffer;		/* parameter except command block */
+	u32	arglen;		/* length above                   */
+};
+
+enum lv1_atapi_proto {
+	NON_DATA_PROTO     = 0,
+	PIO_DATA_IN_PROTO  = 1,
+	PIO_DATA_OUT_PROTO = 2,
+	DMA_PROTO = 3
+};
+
+enum lv1_atapi_in_out {
+	DIR_WRITE = 0,		/* memory -> device */
+	DIR_READ = 1		/* device -> memory */
+};
+
+
+static int ps3rom_slave_configure(struct scsi_device *scsi_dev)
+{
+	struct ps3rom_private *priv = shost_priv(scsi_dev->host);
+	struct ps3_storage_device *dev = priv->dev;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: id %u, lun %u, channel %u\n", __func__,
+		__LINE__, scsi_dev->id, scsi_dev->lun, scsi_dev->channel);
+
+	/*
+	 * ATAPI SFF8020 devices use MODE_SENSE_10,
+	 * so we can prohibit MODE_SENSE_6
+	 */
+	scsi_dev->use_10_for_ms = 1;
+
+	/* we don't support {READ,WRITE}_6 */
+	scsi_dev->use_10_for_rw = 1;
+
+	return 0;
+}
+
+/*
+ * copy data from device into scatter/gather buffer
+ */
+static int fill_from_dev_buffer(struct scsi_cmnd *cmd, const void *buf)
+{
+	int k, req_len, act_len, len, active;
+	void *kaddr;
+	struct scatterlist *sgpnt;
+	unsigned int buflen;
+
+	buflen = cmd->request_bufflen;
+	if (!buflen)
+		return 0;
+
+	if (!cmd->request_buffer)
+		return -1;
+
+	sgpnt = cmd->request_buffer;
+	active = 1;
+	for (k = 0, req_len = 0, act_len = 0; k < cmd->use_sg; ++k, ++sgpnt) {
+		if (active) {
+			kaddr = kmap_atomic(sgpnt->page, KM_IRQ0);
+			len = sgpnt->length;
+			if ((req_len + len) > buflen) {
+				active = 0;
+				len = buflen - req_len;
+			}
+			memcpy(kaddr + sgpnt->offset, buf + req_len, len);
+			flush_kernel_dcache_page(sgpnt->page);
+			kunmap_atomic(kaddr, KM_IRQ0);
+			act_len += len;
+		}
+		req_len += sgpnt->length;
+	}
+	cmd->resid = req_len - act_len;
+	return 0;
+}
+
+/*
+ * copy data from scatter/gather into device's buffer
+ */
+static int fetch_to_dev_buffer(struct scsi_cmnd *cmd, void *buf)
+{
+	int k, req_len, len, fin;
+	void *kaddr;
+	struct scatterlist *sgpnt;
+	unsigned int buflen;
+
+	buflen = cmd->request_bufflen;
+	if (!buflen)
+		return 0;
+
+	if (!cmd->request_buffer)
+		return -1;
+
+	sgpnt = cmd->request_buffer;
+	for (k = 0, req_len = 0, fin = 0; k < cmd->use_sg; ++k, ++sgpnt) {
+		kaddr = kmap_atomic(sgpnt->page, KM_IRQ0);
+		len = sgpnt->length;
+		if ((req_len + len) > buflen) {
+			len = buflen - req_len;
+			fin = 1;
+		}
+		memcpy(buf + req_len, kaddr + sgpnt->offset, len);
+		kunmap_atomic(kaddr, KM_IRQ0);
+		if (fin)
+			return req_len + len;
+		req_len += sgpnt->length;
+	}
+	return req_len;
+}
+
+static int ps3rom_atapi_request(struct ps3_storage_device *dev,
+				struct scsi_cmnd *cmd)
+{
+	struct lv1_atapi_cmnd_block atapi_cmnd;
+	unsigned char opcode = cmd->cmnd[0];
+	int res;
+	u64 lpar;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: send ATAPI command 0x%02x\n", __func__,
+		__LINE__, opcode);
+
+	memset(&atapi_cmnd, 0, sizeof(struct lv1_atapi_cmnd_block));
+	memcpy(&atapi_cmnd.pkt, cmd->cmnd, 12);
+	atapi_cmnd.pktlen = 12;
+	atapi_cmnd.block_size = 1; /* transfer size is block_size * blocks */
+	atapi_cmnd.blocks = atapi_cmnd.arglen = cmd->request_bufflen;
+	atapi_cmnd.buffer = dev->bounce_lpar;
+
+	switch (cmd->sc_data_direction) {
+	case DMA_FROM_DEVICE:
+		if (cmd->request_bufflen >= CD_FRAMESIZE)
+			atapi_cmnd.proto = DMA_PROTO;
+		else
+			atapi_cmnd.proto = PIO_DATA_IN_PROTO;
+		atapi_cmnd.in_out = DIR_READ;
+		break;
+
+	case DMA_TO_DEVICE:
+		if (cmd->request_bufflen >= CD_FRAMESIZE)
+			atapi_cmnd.proto = DMA_PROTO;
+		else
+			atapi_cmnd.proto = PIO_DATA_OUT_PROTO;
+		atapi_cmnd.in_out = DIR_WRITE;
+		res = fetch_to_dev_buffer(cmd, dev->bounce_buf);
+		if (res < 0)
+			return DID_ERROR << 16;
+		break;
+
+	default:
+		atapi_cmnd.proto = NON_DATA_PROTO;
+		break;
+	}
+
+	lpar = ps3_mm_phys_to_lpar(__pa(&atapi_cmnd));
+	res = lv1_storage_send_device_command(dev->sbd.dev_id,
+					      LV1_STORAGE_SEND_ATAPI_COMMAND,
+					      lpar, sizeof(atapi_cmnd),
+					      atapi_cmnd.buffer,
+					      atapi_cmnd.arglen, &dev->tag);
+	if (res == LV1_DENIED_BY_POLICY) {
+		dev_dbg(&dev->sbd.core,
+			"%s:%u: ATAPI command 0x%02x denied by policy\n",
+			__func__, __LINE__, opcode);
+		return DID_ERROR << 16;
+	}
+
+	if (res) {
+		dev_err(&dev->sbd.core,
+			"%s:%u: ATAPI command 0x%02x failed %d\n", __func__,
+			__LINE__, opcode, res);
+		return DID_ERROR << 16;
+	}
+
+	return 0;
+}
+
+static inline unsigned int srb10_lba(const struct scsi_cmnd *cmd)
+{
+	return cmd->cmnd[2] << 24 | cmd->cmnd[3] << 16 | cmd->cmnd[4] << 8 |
+	       cmd->cmnd[5];
+}
+
+static inline unsigned int srb10_len(const struct scsi_cmnd *cmd)
+{
+	return cmd->cmnd[7] << 8 | cmd->cmnd[8];
+}
+
+static int ps3rom_read_request(struct ps3_storage_device *dev,
+			       struct scsi_cmnd *cmd, u32 start_sector,
+			       u32 sectors)
+{
+	int res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: read %u sectors starting at %u\n",
+		__func__, __LINE__, sectors, start_sector);
+
+	res = lv1_storage_read(dev->sbd.dev_id,
+			       dev->regions[dev->region_idx].id, start_sector,
+			       sectors, 0, dev->bounce_lpar, &dev->tag);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: read failed %d\n", __func__,
+			__LINE__, res);
+		return DID_ERROR << 16;
+	}
+
+	return 0;
+}
+
+static int ps3rom_write_request(struct ps3_storage_device *dev,
+				struct scsi_cmnd *cmd, u32 start_sector,
+				u32 sectors)
+{
+	int res;
+
+	dev_dbg(&dev->sbd.core, "%s:%u: write %u sectors starting at %u\n",
+		__func__, __LINE__, sectors, start_sector);
+
+	res = fetch_to_dev_buffer(cmd, dev->bounce_buf);
+	if (res < 0)
+		return DID_ERROR << 16;
+
+	res = lv1_storage_write(dev->sbd.dev_id,
+				dev->regions[dev->region_idx].id, start_sector,
+				sectors, 0, dev->bounce_lpar, &dev->tag);
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: write failed %d\n", __func__,
+			__LINE__, res);
+		return DID_ERROR << 16;
+	}
+
+	return 0;
+}
+
+static int ps3rom_queuecommand(struct scsi_cmnd *cmd,
+			       void (*done)(struct scsi_cmnd *))
+{
+	struct ps3rom_private *priv = shost_priv(cmd->device->host);
+	struct ps3_storage_device *dev = priv->dev;
+	unsigned char opcode;
+	int res;
+
+#ifdef DEBUG
+	scsi_print_command(cmd);
+#endif
+
+	priv->curr_cmd = cmd;
+	cmd->scsi_done = done;
+
+	opcode = cmd->cmnd[0];
+	/*
+	 * While we can submit READ/WRITE SCSI commands as ATAPI commands,
+	 * it's recommended for various reasons (performance, error handling,
+	 * ...) to use lv1_storage_{read,write}() instead
+	 */
+	switch (opcode) {
+	case READ_10:
+		res = ps3rom_read_request(dev, cmd, srb10_lba(cmd),
+					  srb10_len(cmd));
+		break;
+
+	case WRITE_10:
+		res = ps3rom_write_request(dev, cmd, srb10_lba(cmd),
+					   srb10_len(cmd));
+		break;
+
+	default:
+		res = ps3rom_atapi_request(dev, cmd);
+		break;
+	}
+
+	if (res) {
+		memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
+		cmd->result = res;
+		cmd->sense_buffer[0] = 0x70;
+		cmd->sense_buffer[2] = ILLEGAL_REQUEST;
+		priv->curr_cmd = NULL;
+		cmd->scsi_done(cmd);
+	}
+
+	return 0;
+}
+
+static int decode_lv1_status(u64 status, unsigned char *sense_key,
+			     unsigned char *asc, unsigned char *ascq)
+{
+	if (((status >> 24) & 0xff) != SAM_STAT_CHECK_CONDITION)
+		return -1;
+
+	*sense_key = (status >> 16) & 0xff;
+	*asc       = (status >>  8) & 0xff;
+	*ascq      =  status        & 0xff;
+	return 0;
+}
+
+static irqreturn_t ps3rom_interrupt(int irq, void *data)
+{
+	struct ps3_storage_device *dev = data;
+	struct Scsi_Host *host;
+	struct ps3rom_private *priv;
+	struct scsi_cmnd *cmd;
+	int res;
+	u64 tag, status;
+	unsigned char sense_key, asc, ascq;
+
+	res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
+	/*
+	 * status = -1 may mean that ATAPI transport completed OK, but
+	 * ATAPI command itself resulted CHECK CONDITION
+	 * so, upper layer should issue REQUEST_SENSE to check the sense data
+	 */
+
+	if (tag != dev->tag)
+		dev_err(&dev->sbd.core,
+			"%s:%u: tag mismatch, got %lx, expected %lx\n",
+			__func__, __LINE__, tag, dev->tag);
+
+	if (res) {
+		dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%lx\n",
+			__func__, __LINE__, res, status);
+		return IRQ_HANDLED;
+	}
+
+	host = dev->sbd.core.driver_data;
+	priv = shost_priv(host);
+	cmd = priv->curr_cmd;
+
+	if (!status) {
+		/* OK, completed */
+		if (cmd->sc_data_direction == DMA_FROM_DEVICE) {
+			res = fill_from_dev_buffer(cmd, dev->bounce_buf);
+			if (res) {
+				cmd->result = DID_ERROR << 16;
+				goto done;
+			}
+		}
+		cmd->result = DID_OK << 16;
+		goto done;
+	}
+
+	if (cmd->cmnd[0] == REQUEST_SENSE) {
+		/* SCSI spec says request sense should never get error */
+		dev_err(&dev->sbd.core, "%s:%u: end error without autosense\n",
+			__func__, __LINE__);
+		cmd->result = DID_ERROR << 16 | SAM_STAT_CHECK_CONDITION;
+		goto done;
+	}
+
+	if (decode_lv1_status(status, &sense_key, &asc, &ascq)) {
+		cmd->result = DID_ERROR << 16;
+		goto done;
+	}
+
+	cmd->sense_buffer[0]  = 0x70;
+	cmd->sense_buffer[2]  = sense_key;
+	cmd->sense_buffer[7]  = 16 - 6;
+	cmd->sense_buffer[12] = asc;
+	cmd->sense_buffer[13] = ascq;
+	cmd->result = SAM_STAT_CHECK_CONDITION;
+
+done:
+	priv->curr_cmd = NULL;
+	cmd->scsi_done(cmd);
+	return IRQ_HANDLED;
+}
+
+static struct scsi_host_template ps3rom_host_template = {
+	.name =			DEVICE_NAME,
+	.slave_configure =	ps3rom_slave_configure,
+	.queuecommand =		ps3rom_queuecommand,
+	.can_queue =		1,
+	.this_id =		7,
+	.sg_tablesize =		SG_ALL,
+	.cmd_per_lun =		1,
+	.emulated =             1,		/* only sg driver uses this */
+	.max_sectors =		PS3ROM_MAX_SECTORS,
+	.use_clustering =	ENABLE_CLUSTERING,
+	.module =		THIS_MODULE,
+};
+
+
+static int __devinit ps3rom_probe(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+	int error;
+	struct Scsi_Host *host;
+	struct ps3rom_private *priv;
+
+	if (dev->blk_size != CD_FRAMESIZE) {
+		dev_err(&dev->sbd.core,
+			"%s:%u: cannot handle block size %lu\n", __func__,
+			__LINE__, dev->blk_size);
+		return -EINVAL;
+	}
+
+	dev->bounce_size = BOUNCE_SIZE;
+	dev->bounce_buf = kmalloc(BOUNCE_SIZE, GFP_DMA);
+	if (!dev->bounce_buf)
+		return -ENOMEM;
+
+	error = ps3stor_setup(dev, ps3rom_interrupt);
+	if (error)
+		goto fail_free_bounce;
+
+	host = scsi_host_alloc(&ps3rom_host_template,
+			       sizeof(struct ps3rom_private));
+	if (!host) {
+		dev_err(&dev->sbd.core, "%s:%u: scsi_host_alloc failed\n",
+			__func__, __LINE__);
+		goto fail_teardown;
+	}
+
+	priv = shost_priv(host);
+	dev->sbd.core.driver_data = host;
+	priv->dev = dev;
+
+	/* One device/LUN per SCSI bus */
+	host->max_id = 1;
+	host->max_lun = 1;
+
+	error = scsi_add_host(host, &dev->sbd.core);
+	if (error) {
+		dev_err(&dev->sbd.core, "%s:%u: scsi_host_alloc failed %d\n",
+			__func__, __LINE__, error);
+		error = -ENODEV;
+		goto fail_host_put;
+	}
+
+	scsi_scan_host(host);
+	return 0;
+
+fail_host_put:
+	scsi_host_put(host);
+	dev->sbd.core.driver_data = NULL;
+fail_teardown:
+	ps3stor_teardown(dev);
+fail_free_bounce:
+	kfree(dev->bounce_buf);
+	return error;
+}
+
+static int ps3rom_remove(struct ps3_system_bus_device *_dev)
+{
+	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
+	struct Scsi_Host *host = dev->sbd.core.driver_data;
+
+	scsi_remove_host(host);
+	ps3stor_teardown(dev);
+	scsi_host_put(host);
+	dev->sbd.core.driver_data = NULL;
+	kfree(dev->bounce_buf);
+	return 0;
+}
+
+static struct ps3_system_bus_driver ps3rom = {
+	.match_id	= PS3_MATCH_ID_STOR_ROM,
+	.core.name	= DEVICE_NAME,
+	.core.owner	= THIS_MODULE,
+	.probe		= ps3rom_probe,
+	.remove		= ps3rom_remove
+};
+
+
+static int __init ps3rom_init(void)
+{
+	return ps3_system_bus_driver_register(&ps3rom);
+}
+
+static void __exit ps3rom_exit(void)
+{
+	ps3_system_bus_driver_unregister(&ps3rom);
+}
+
+module_init(ps3rom_init);
+module_exit(ps3rom_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PS3 BD/DVD/CD-ROM Storage Driver");
+MODULE_AUTHOR("Sony Corporation");
+MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_ROM);