[GitHub/LineageOS/android_kernel_samsung_universal7580.git] / drivers / scsi / ibmvscsi / rpa_vscsi.c

/* ------------------------------------------------------------
 * rpa_vscsi.c
 * (C) Copyright IBM Corporation 1994, 2003
 * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
 *          Santiago Leon (santil@us.ibm.com)
 *
 * 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
 * (at your option) 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA
 *
 * ------------------------------------------------------------
 * RPA-specific functions of the SCSI host adapter for Virtual I/O devices
 *
 * This driver allows the Linux SCSI peripheral drivers to directly
 * access devices in the hosting partition, either on an iSeries
 * hypervisor system or a converged hypervisor system.
 */

#include <asm/vio.h>
#include <asm/prom.h>
#include <asm/iommu.h>
#include <asm/hvcall.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include "ibmvscsi.h"
#include "srp.h"

static char partition_name[97] = "UNKNOWN";
static unsigned int partition_number = -1;

/* ------------------------------------------------------------
 * Routines for managing the command/response queue
 */
/**
 * ibmvscsi_handle_event: - Interrupt handler for crq events
 * @irq:	number of irq to handle, not used
 * @dev_instance: ibmvscsi_host_data of host that received interrupt
 * @regs:	pt_regs with registers
 *
 * Disables interrupts and schedules srp_task
 * Always returns IRQ_HANDLED
 */
static irqreturn_t ibmvscsi_handle_event(int irq,
					 void *dev_instance,
					 struct pt_regs *regs)
{
	struct ibmvscsi_host_data *hostdata =
	    (struct ibmvscsi_host_data *)dev_instance;
	vio_disable_interrupts(to_vio_dev(hostdata->dev));
	tasklet_schedule(&hostdata->srp_task);
	return IRQ_HANDLED;
}

/**
 * release_crq_queue: - Deallocates data and unregisters CRQ
 * @queue:	crq_queue to initialize and register
 * @host_data:	ibmvscsi_host_data of host
 *
 * Frees irq, deallocates a page for messages, unmaps dma, and unregisters
 * the crq with the hypervisor.
 */
void ibmvscsi_release_crq_queue(struct crq_queue *queue,
				struct ibmvscsi_host_data *hostdata,
				int max_requests)
{
	long rc;
	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
	free_irq(vdev->irq, (void *)hostdata);
	tasklet_kill(&hostdata->srp_task);
	do {
		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	} while ((rc == H_Busy) || (H_isLongBusy(rc)));
	dma_unmap_single(hostdata->dev,
			 queue->msg_token,
			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
	free_page((unsigned long)queue->msgs);
}

/**
 * crq_queue_next_crq: - Returns the next entry in message queue
 * @queue:	crq_queue to use
 *
 * Returns pointer to next entry in queue, or NULL if there are no new 
 * entried in the CRQ.
 */
static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
{
	struct viosrp_crq *crq;
	unsigned long flags;

	spin_lock_irqsave(&queue->lock, flags);
	crq = &queue->msgs[queue->cur];
	if (crq->valid & 0x80) {
		if (++queue->cur == queue->size)
			queue->cur = 0;
	} else
		crq = NULL;
	spin_unlock_irqrestore(&queue->lock, flags);

	return crq;
}

/**
 * ibmvscsi_send_crq: - Send a CRQ
 * @hostdata:	the adapter
 * @word1:	the first 64 bits of the data
 * @word2:	the second 64 bits of the data
 */
int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata, u64 word1, u64 word2)
{
	struct vio_dev *vdev = to_vio_dev(hostdata->dev);

	return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
}

/**
 * ibmvscsi_task: - Process srps asynchronously
 * @data:	ibmvscsi_host_data of host
 */
static void ibmvscsi_task(void *data)
{
	struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data;
	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
	struct viosrp_crq *crq;
	int done = 0;

	while (!done) {
		/* Pull all the valid messages off the CRQ */
		while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
			ibmvscsi_handle_crq(crq, hostdata);
			crq->valid = 0x00;
		}

		vio_enable_interrupts(vdev);
		if ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
			vio_disable_interrupts(vdev);
			ibmvscsi_handle_crq(crq, hostdata);
			crq->valid = 0x00;
		} else {
			done = 1;
		}
	}
}

static void gather_partition_info(void)
{
	struct device_node *rootdn;

	char *ppartition_name;
	unsigned int *p_number_ptr;

	/* Retrieve information about this partition */
	rootdn = find_path_device("/");
	if (!rootdn) {
		return;
	}

	ppartition_name =
		get_property(rootdn, "ibm,partition-name", NULL);
	if (ppartition_name)
		strncpy(partition_name, ppartition_name,
				sizeof(partition_name));
	p_number_ptr =
		(unsigned int *)get_property(rootdn, "ibm,partition-no",
					     NULL);
	if (p_number_ptr)
		partition_number = *p_number_ptr;
}

static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
{
	memset(&hostdata->madapter_info, 0x00,
			sizeof(hostdata->madapter_info));

	printk(KERN_INFO "rpa_vscsi: SPR_VERSION: %s\n", SRP_VERSION);
	strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);

	strncpy(hostdata->madapter_info.partition_name, partition_name,
			sizeof(hostdata->madapter_info.partition_name));

	hostdata->madapter_info.partition_number = partition_number;

	hostdata->madapter_info.mad_version = 1;
	hostdata->madapter_info.os_type = 2;
}

/**
 * initialize_crq_queue: - Initializes and registers CRQ with hypervisor
 * @queue:	crq_queue to initialize and register
 * @hostdata:	ibmvscsi_host_data of host
 *
 * Allocates a page for messages, maps it for dma, and registers
 * the crq with the hypervisor.
 * Returns zero on success.
 */
int ibmvscsi_init_crq_queue(struct crq_queue *queue,
			    struct ibmvscsi_host_data *hostdata,
			    int max_requests)
{
	int rc;
	struct vio_dev *vdev = to_vio_dev(hostdata->dev);

	queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);

	if (!queue->msgs)
		goto malloc_failed;
	queue->size = PAGE_SIZE / sizeof(*queue->msgs);

	queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
					  queue->size * sizeof(*queue->msgs),
					  DMA_BIDIRECTIONAL);

	if (dma_mapping_error(queue->msg_token))
		goto map_failed;

	gather_partition_info();
	set_adapter_info(hostdata);

	rc = plpar_hcall_norets(H_REG_CRQ,
				vdev->unit_address,
				queue->msg_token, PAGE_SIZE);
	if (rc == 2) {
		/* Adapter is good, but other end is not ready */
		printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
	} else if (rc != 0) {
		printk(KERN_WARNING "ibmvscsi: Error %d opening adapter\n", rc);
		goto reg_crq_failed;
	}

	if (request_irq(vdev->irq,
			ibmvscsi_handle_event,
			0, "ibmvscsi", (void *)hostdata) != 0) {
		printk(KERN_ERR "ibmvscsi: couldn't register irq 0x%x\n",
		       vdev->irq);
		goto req_irq_failed;
	}

	rc = vio_enable_interrupts(vdev);
	if (rc != 0) {
		printk(KERN_ERR "ibmvscsi:  Error %d enabling interrupts!!!\n",
		       rc);
		goto req_irq_failed;
	}

	queue->cur = 0;
	spin_lock_init(&queue->lock);

	tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
		     (unsigned long)hostdata);

	return 0;

      req_irq_failed:
	do {
		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	} while ((rc == H_Busy) || (H_isLongBusy(rc)));
      reg_crq_failed:
	dma_unmap_single(hostdata->dev,
			 queue->msg_token,
			 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
      map_failed:
	free_page((unsigned long)queue->msgs);
      malloc_failed:
	return -1;
}

/**
 * reset_crq_queue: - resets a crq after a failure
 * @queue:	crq_queue to initialize and register
 * @hostdata:	ibmvscsi_host_data of host
 *
 */
void ibmvscsi_reset_crq_queue(struct crq_queue *queue,
			      struct ibmvscsi_host_data *hostdata)
{
	int rc;
	struct vio_dev *vdev = to_vio_dev(hostdata->dev);

	/* Close the CRQ */
	do {
		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	} while ((rc == H_Busy) || (H_isLongBusy(rc)));

	/* Clean out the queue */
	memset(queue->msgs, 0x00, PAGE_SIZE);
	queue->cur = 0;

	set_adapter_info(hostdata);

	/* And re-open it again */
	rc = plpar_hcall_norets(H_REG_CRQ,
				vdev->unit_address,
				queue->msg_token, PAGE_SIZE);
	if (rc == 2) {
		/* Adapter is good, but other end is not ready */
		printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
	} else if (rc != 0) {
		printk(KERN_WARNING
		       "ibmvscsi: couldn't register crq--rc 0x%x\n", rc);
	}
}
Commit	Line	Data
1da177e4 LT	1	/* ------------------------------------------------------------
	2	* rpa_vscsi.c
	3	* (C) Copyright IBM Corporation 1994, 2003
	4	* Authors: Colin DeVilbiss (devilbis@us.ibm.com)
	5	* Santiago Leon (santil@us.ibm.com)
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
	20	* USA
	21	*
	22	* ------------------------------------------------------------
	23	* RPA-specific functions of the SCSI host adapter for Virtual I/O devices
	24	*
	25	* This driver allows the Linux SCSI peripheral drivers to directly
	26	* access devices in the hosting partition, either on an iSeries
	27	* hypervisor system or a converged hypervisor system.
	28	*/
	29
	30	#include <asm/vio.h>
71d276d7	31	#include <asm/prom.h>
1da177e4 LT	32	#include <asm/iommu.h>
	33	#include <asm/hvcall.h>
	34	#include <linux/dma-mapping.h>
	35	#include <linux/interrupt.h>
	36	#include "ibmvscsi.h"
b4687ca4 LX	37	#include "srp.h"
	38
	39	static char partition_name[97] = "UNKNOWN";
	40	static unsigned int partition_number = -1;
1da177e4 LT	41
	42	/* ------------------------------------------------------------
	43	* Routines for managing the command/response queue
	44	*/
	45	/**
	46	* ibmvscsi_handle_event: - Interrupt handler for crq events
	47	* @irq: number of irq to handle, not used
	48	* @dev_instance: ibmvscsi_host_data of host that received interrupt
	49	* @regs: pt_regs with registers
	50	*
	51	* Disables interrupts and schedules srp_task
	52	* Always returns IRQ_HANDLED
	53	*/
	54	static irqreturn_t ibmvscsi_handle_event(int irq,
	55	void *dev_instance,
	56	struct pt_regs *regs)
	57	{
	58	struct ibmvscsi_host_data *hostdata =
	59	(struct ibmvscsi_host_data *)dev_instance;
	60	vio_disable_interrupts(to_vio_dev(hostdata->dev));
	61	tasklet_schedule(&hostdata->srp_task);
	62	return IRQ_HANDLED;
	63	}
	64
	65	/**
	66	* release_crq_queue: - Deallocates data and unregisters CRQ
	67	* @queue: crq_queue to initialize and register
	68	* @host_data: ibmvscsi_host_data of host
	69	*
	70	* Frees irq, deallocates a page for messages, unmaps dma, and unregisters
	71	* the crq with the hypervisor.
	72	*/
	73	void ibmvscsi_release_crq_queue(struct crq_queue *queue,
	74	struct ibmvscsi_host_data *hostdata,
	75	int max_requests)
	76	{
	77	long rc;
	78	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
	79	free_irq(vdev->irq, (void *)hostdata);
	80	tasklet_kill(&hostdata->srp_task);
	81	do {
	82	rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	83	} while ((rc == H_Busy) \|\| (H_isLongBusy(rc)));
	84	dma_unmap_single(hostdata->dev,
	85	queue->msg_token,
	86	queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
	87	free_page((unsigned long)queue->msgs);
	88	}
	89
	90	/**
	91	* crq_queue_next_crq: - Returns the next entry in message queue
	92	* @queue: crq_queue to use
	93	*
	94	* Returns pointer to next entry in queue, or NULL if there are no new
	95	* entried in the CRQ.
	96	*/
	97	static struct viosrp_crq crq_queue_next_crq(struct crq_queue queue)
	98	{
	99	struct viosrp_crq *crq;
	100	unsigned long flags;
	101
	102	spin_lock_irqsave(&queue->lock, flags);
	103	crq = &queue->msgs[queue->cur];
	104	if (crq->valid & 0x80) {
105	if (++queue->cur == queue->size)
106	queue->cur = 0;
107	} else
108	crq = NULL;
109	spin_unlock_irqrestore(&queue->lock, flags);
110
111	return crq;
112	}
113
114	/**
115	* ibmvscsi_send_crq: - Send a CRQ
116	* @hostdata: the adapter
117	* @word1: the first 64 bits of the data
118	* @word2: the second 64 bits of the data
119	*/
120	int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata, u64 word1, u64 word2)
121	{
122	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
123
124	return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
125	}
126
127	/**
128	* ibmvscsi_task: - Process srps asynchronously
129	* @data: ibmvscsi_host_data of host
130	*/
131	static void ibmvscsi_task(void *data)
132	{
133	struct ibmvscsi_host_data hostdata = (struct ibmvscsi_host_data )data;
134	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
135	struct viosrp_crq *crq;
136	int done = 0;
137
138	while (!done) {
139	/* Pull all the valid messages off the CRQ */
140	while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
141	ibmvscsi_handle_crq(crq, hostdata);
142	crq->valid = 0x00;
143	}
144
145	vio_enable_interrupts(vdev);
146	if ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
147	vio_disable_interrupts(vdev);
148	ibmvscsi_handle_crq(crq, hostdata);
149	crq->valid = 0x00;
150	} else {
151	done = 1;
152	}
153	}
154	}
155
b4687ca4 LX	156	static void gather_partition_info(void)
	157	{
	158	struct device_node *rootdn;
	159
	160	char *ppartition_name;
	161	unsigned int *p_number_ptr;
	162
	163	/* Retrieve information about this partition */
	164	rootdn = find_path_device("/");
	165	if (!rootdn) {
	166	return;
	167	}
	168
	169	ppartition_name =
	170	get_property(rootdn, "ibm,partition-name", NULL);
	171	if (ppartition_name)
	172	strncpy(partition_name, ppartition_name,
	173	sizeof(partition_name));
	174	p_number_ptr =
	175	(unsigned int *)get_property(rootdn, "ibm,partition-no",
	176	NULL);
	177	if (p_number_ptr)
	178	partition_number = *p_number_ptr;
	179	}
	180
	181	static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
	182	{
	183	memset(&hostdata->madapter_info, 0x00,
	184	sizeof(hostdata->madapter_info));
	185
	186	printk(KERN_INFO "rpa_vscsi: SPR_VERSION: %s\n", SRP_VERSION);
	187	strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);
	188
	189	strncpy(hostdata->madapter_info.partition_name, partition_name,
	190	sizeof(hostdata->madapter_info.partition_name));
	191
	192	hostdata->madapter_info.partition_number = partition_number;
	193
	194	hostdata->madapter_info.mad_version = 1;
	195	hostdata->madapter_info.os_type = 2;
	196	}
	197
1da177e4 LT	198	/**
	199	* initialize_crq_queue: - Initializes and registers CRQ with hypervisor
	200	* @queue: crq_queue to initialize and register
	201	* @hostdata: ibmvscsi_host_data of host
	202	*
	203	* Allocates a page for messages, maps it for dma, and registers
	204	* the crq with the hypervisor.
	205	* Returns zero on success.
	206	*/
	207	int ibmvscsi_init_crq_queue(struct crq_queue *queue,
	208	struct ibmvscsi_host_data *hostdata,
	209	int max_requests)
	210	{
	211	int rc;
	212	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
	213
	214	queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
	215
	216	if (!queue->msgs)
	217	goto malloc_failed;
	218	queue->size = PAGE_SIZE / sizeof(*queue->msgs);
	219
	220	queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
	221	queue->size * sizeof(*queue->msgs),
	222	DMA_BIDIRECTIONAL);
	223
	224	if (dma_mapping_error(queue->msg_token))
	225	goto map_failed;
	226
b4687ca4 LX	227	gather_partition_info();
	228	set_adapter_info(hostdata);
	229
1da177e4 LT	230	rc = plpar_hcall_norets(H_REG_CRQ,
	231	vdev->unit_address,
	232	queue->msg_token, PAGE_SIZE);
	233	if (rc == 2) {
	234	/* Adapter is good, but other end is not ready */
	235	printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
	236	} else if (rc != 0) {
	237	printk(KERN_WARNING "ibmvscsi: Error %d opening adapter\n", rc);
	238	goto reg_crq_failed;
	239	}
	240
	241	if (request_irq(vdev->irq,
	242	ibmvscsi_handle_event,
	243	0, "ibmvscsi", (void *)hostdata) != 0) {
	244	printk(KERN_ERR "ibmvscsi: couldn't register irq 0x%x\n",
	245	vdev->irq);
	246	goto req_irq_failed;
	247	}
	248
	249	rc = vio_enable_interrupts(vdev);
	250	if (rc != 0) {
	251	printk(KERN_ERR "ibmvscsi: Error %d enabling interrupts!!!\n",
	252	rc);
	253	goto req_irq_failed;
	254	}
	255
	256	queue->cur = 0;
	257	spin_lock_init(&queue->lock);
	258
	259	tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
	260	(unsigned long)hostdata);
	261
	262	return 0;
	263
	264	req_irq_failed:
	265	do {
	266	rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	267	} while ((rc == H_Busy) \|\| (H_isLongBusy(rc)));
	268	reg_crq_failed:
	269	dma_unmap_single(hostdata->dev,
	270	queue->msg_token,
	271	queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
	272	map_failed:
	273	free_page((unsigned long)queue->msgs);
	274	malloc_failed:
	275	return -1;
	276	}
	277
	278	/**
	279	* reset_crq_queue: - resets a crq after a failure
	280	* @queue: crq_queue to initialize and register
	281	* @hostdata: ibmvscsi_host_data of host
	282	*
	283	*/
	284	void ibmvscsi_reset_crq_queue(struct crq_queue *queue,
	285	struct ibmvscsi_host_data *hostdata)
	286	{
	287	int rc;
	288	struct vio_dev *vdev = to_vio_dev(hostdata->dev);
	289
	290	/* Close the CRQ */
	291	do {
	292	rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
	293	} while ((rc == H_Busy) \|\| (H_isLongBusy(rc)));
294
295	/* Clean out the queue */
296	memset(queue->msgs, 0x00, PAGE_SIZE);
297	queue->cur = 0;
298
b4687ca4 LX	299	set_adapter_info(hostdata);
b4687ca4 LX	300
1da177e4 LT	301	/* And re-open it again */
	302	rc = plpar_hcall_norets(H_REG_CRQ,
	303	vdev->unit_address,
	304	queue->msg_token, PAGE_SIZE);
	305	if (rc == 2) {
	306	/* Adapter is good, but other end is not ready */
	307	printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
	308	} else if (rc != 0) {
	309	printk(KERN_WARNING
	310	"ibmvscsi: couldn't register crq--rc 0x%x\n", rc);
	311	}
	312	}