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 0f8689557158..86a7ba7bad63 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 000000000000..b50f1e14f2a5
--- /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);