drivers/scsi/sgiwd93.c - linux - Git at Google

 /*
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
  * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
  * Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
  * Copyright (C) 2003, 07 Ralf Baechle (ralf@linux-mips.org)
  *
  * (In all truth, Jed Schimmel wrote all this code.)
  */

 #undef DEBUG

 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
 #include <linux/gfp.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>

 #include <asm/sgi/hpc3.h>
 #include <asm/sgi/ip22.h>
 #include <asm/sgi/wd.h>

 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_tcq.h>
 #include "wd33c93.h"

 struct ip22_hostdata {
 	struct WD33C93_hostdata wh;
 	dma_addr_t dma;
 	void *cpu;
 	struct device *dev;
 };

 #define host_to_hostdata(host) ((struct ip22_hostdata *)((host)->hostdata))

 struct hpc_chunk {
 	struct hpc_dma_desc desc;
 	u32 _padding;	/* align to quadword boundary */
 };

 /* space for hpc dma descriptors */
 #define HPC_DMA_SIZE   PAGE_SIZE

 #define DMA_DIR(d)   ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)

 static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
 {
 	struct Scsi_Host * host = dev_id;
 	unsigned long flags;

 	spin_lock_irqsave(host->host_lock, flags);
 	wd33c93_intr(host);
 	spin_unlock_irqrestore(host->host_lock, flags);

 	return IRQ_HANDLED;
 }

 static inline
 void fill_hpc_entries(struct ip22_hostdata *hd, struct scsi_cmnd *cmd, int din)
 {
 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
 	unsigned long len = scsi_pointer->this_residual;
 	void *addr = scsi_pointer->ptr;
 	dma_addr_t physaddr;
 	unsigned long count;
 	struct hpc_chunk *hcp;

 	physaddr = dma_map_single(hd->dev, addr, len, DMA_DIR(din));
 	scsi_pointer->dma_handle = physaddr;
 	hcp = hd->cpu;

 	while (len) {
 		/*
 		 * even cntinfo could be up to 16383, without
 		 * magic only 8192 works correctly
 		 */
 		count = len > 8192 ? 8192 : len;
 		hcp->desc.pbuf = physaddr;
 		hcp->desc.cntinfo = count;
 		hcp++;
 		len -= count;
 		physaddr += count;
 	}

 	/*
 	 * To make sure, if we trip an HPC bug, that we transfer every single
 	 * byte, we tag on an extra zero length dma descriptor at the end of
 	 * the chain.
 	 */
 	hcp->desc.pbuf = 0;
 	hcp->desc.cntinfo = HPCDMA_EOX;
 	dma_sync_single_for_device(hd->dev, hd->dma,
 		       (unsigned long)(hcp + 1) - (unsigned long)hd->cpu,
 		       DMA_TO_DEVICE);
 }

 static int dma_setup(struct scsi_cmnd *cmd, int datainp)
 {
 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
 	struct ip22_hostdata *hdata = host_to_hostdata(cmd->device->host);
 	struct hpc3_scsiregs *hregs =
 		(struct hpc3_scsiregs *) cmd->device->host->base;

 	pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hdata->cpu);

 	hdata->wh.dma_dir = datainp;

 	/*
 	 * wd33c93 shouldn't pass us bogus dma_setups, but it does:-(  The
 	 * other wd33c93 drivers deal with it the same way (which isn't that
 	 * obvious).  IMHO a better fix would be, not to do these dma setups
 	 * in the first place.
 	 */
 	if (scsi_pointer->ptr == NULL || scsi_pointer->this_residual == 0)
 		return 1;

 	fill_hpc_entries(hdata, cmd, datainp);

 	pr_debug(" HPCGO\n");

 	/* Start up the HPC. */
 	hregs->ndptr = hdata->dma;
 	if (datainp)
 		hregs->ctrl = HPC3_SCTRL_ACTIVE;
 	else
 		hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;

 	return 0;
 }

 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
 		     int status)
 {
 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
 	struct ip22_hostdata *hdata = host_to_hostdata(instance);
 	struct hpc3_scsiregs *hregs;

 	if (!SCpnt)
 		return;

 	if (scsi_pointer->ptr == NULL || scsi_pointer->this_residual == 0)
 		return;

 	hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;

 	pr_debug("dma_stop: status<%d> ", status);

 	/* First stop the HPC and flush it's FIFO. */
 	if (hdata->wh.dma_dir) {
 		hregs->ctrl |= HPC3_SCTRL_FLUSH;
 		while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
 			barrier();
 	}
 	hregs->ctrl = 0;
 	dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
 			 scsi_pointer->this_residual,
 			 DMA_DIR(hdata->wh.dma_dir));

 	pr_debug("\n");
 }

 void sgiwd93_reset(unsigned long base)
 {
 	struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;

 	hregs->ctrl = HPC3_SCTRL_CRESET;
 	udelay(50);
 	hregs->ctrl = 0;
 }
 EXPORT_SYMBOL_GPL(sgiwd93_reset);

 static inline void init_hpc_chain(struct ip22_hostdata *hdata)
 {
 	struct hpc_chunk *hcp = (struct hpc_chunk *)hdata->cpu;
 	dma_addr_t dma = hdata->dma;
 	unsigned long start, end;

 	start = (unsigned long) hcp;
 	end = start + HPC_DMA_SIZE;
 	while (start < end) {
 		hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk));
 		hcp->desc.cntinfo = HPCDMA_EOX;
 		hcp++;
 		dma += sizeof(struct hpc_chunk);
 		start += sizeof(struct hpc_chunk);
 	}
 	hcp--;
 	hcp->desc.pnext = hdata->dma;
 }

 /*
  * Kludge alert - the SCSI code calls the abort and reset method with int
  * arguments not with pointers.  So this is going to blow up beautyfully
  * on 64-bit systems with memory outside the compat address spaces.
  */
 static const struct scsi_host_template sgiwd93_template = {
 	.module			= THIS_MODULE,
 	.proc_name		= "SGIWD93",
 	.name			= "SGI WD93",
 	.queuecommand		= wd33c93_queuecommand,
 	.eh_abort_handler	= wd33c93_abort,
 	.eh_host_reset_handler	= wd33c93_host_reset,
 	.can_queue		= 16,
 	.this_id		= 7,
 	.sg_tablesize		= SG_ALL,
 	.cmd_per_lun		= 8,
 	.dma_boundary		= PAGE_SIZE - 1,
 	.cmd_size		= sizeof(struct scsi_pointer),
 };

 static int sgiwd93_probe(struct platform_device *pdev)
 {
 	struct sgiwd93_platform_data *pd = pdev->dev.platform_data;
 	unsigned char *wdregs = pd->wdregs;
 	struct hpc3_scsiregs *hregs = pd->hregs;
 	struct ip22_hostdata *hdata;
 	struct Scsi_Host *host;
 	wd33c93_regs regs;
 	unsigned int unit = pd->unit;
 	unsigned int irq = pd->irq;
 	int err;

 	host = scsi_host_alloc(&sgiwd93_template, sizeof(struct ip22_hostdata));
 	if (!host) {
 		err = -ENOMEM;
 		goto out;
 	}

 	host->base = (unsigned long) hregs;
 	host->irq = irq;

 	hdata = host_to_hostdata(host);
 	hdata->dev = &pdev->dev;
 	hdata->cpu = dma_alloc_noncoherent(&pdev->dev, HPC_DMA_SIZE,
 				&hdata->dma, DMA_TO_DEVICE, GFP_KERNEL);
 	if (!hdata->cpu) {
 		printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
 		       "host %d buffer.\n", unit);
 		err = -ENOMEM;
 		goto out_put;
 	}

 	init_hpc_chain(hdata);

 	regs.SASR = wdregs + 3;
 	regs.SCMD = wdregs + 7;

 	hdata->wh.no_sync = 0;
 	hdata->wh.fast = 1;
 	hdata->wh.dma_mode = CTRL_BURST;

 	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_MHZ(20));

 	err = request_irq(irq, sgiwd93_intr, 0, "SGI WD93", host);
 	if (err) {
 		printk(KERN_WARNING "sgiwd93: Could not register irq %d "
 		       "for host %d.\n", irq, unit);
 		goto out_free;
 	}

 	platform_set_drvdata(pdev, host);

 	err = scsi_add_host(host, NULL);
 	if (err)
 		goto out_irq;

 	scsi_scan_host(host);

 	return 0;

 out_irq:
 	free_irq(irq, host);
 out_free:
 	dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
 			DMA_TO_DEVICE);
 out_put:
 	scsi_host_put(host);
 out:

 	return err;
 }

 static void sgiwd93_remove(struct platform_device *pdev)
 {
 	struct Scsi_Host *host = platform_get_drvdata(pdev);
 	struct ip22_hostdata *hdata = (struct ip22_hostdata *) host->hostdata;
 	struct sgiwd93_platform_data *pd = pdev->dev.platform_data;

 	scsi_remove_host(host);
 	free_irq(pd->irq, host);
 	dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
 			DMA_TO_DEVICE);
 	scsi_host_put(host);
 }

 static struct platform_driver sgiwd93_driver = {
 	.probe  = sgiwd93_probe,
 	.remove_new = sgiwd93_remove,
 	.driver = {
 		.name   = "sgiwd93",
 	}
 };

 static int __init sgiwd93_module_init(void)
 {
 	return platform_driver_register(&sgiwd93_driver);
 }

 static void __exit sgiwd93_module_exit(void)
 {
 	return platform_driver_unregister(&sgiwd93_driver);
 }

 module_init(sgiwd93_module_init);
 module_exit(sgiwd93_module_exit);

 MODULE_DESCRIPTION("SGI WD33C93 driver");
 MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:sgiwd93");
	/*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*
	* Copyright (C) 1996 David S. Miller (davem@davemloft.net)
	* Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
	* Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
	* Copyright (C) 2003, 07 Ralf Baechle (ralf@linux-mips.org)
	*
	* (In all truth, Jed Schimmel wrote all this code.)
	*/

	#undef DEBUG

	#include <linux/delay.h>
	#include <linux/dma-mapping.h>
	#include <linux/gfp.h>
	#include <linux/interrupt.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/types.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/spinlock.h>

	#include <asm/sgi/hpc3.h>
	#include <asm/sgi/ip22.h>
	#include <asm/sgi/wd.h>

	#include <scsi/scsi.h>
	#include <scsi/scsi_cmnd.h>
	#include <scsi/scsi_device.h>
	#include <scsi/scsi_eh.h>
	#include <scsi/scsi_tcq.h>
	#include "wd33c93.h"

	struct ip22_hostdata {
	struct WD33C93_hostdata wh;
	dma_addr_t dma;
	void *cpu;
	struct device *dev;
	};

	#define host_to_hostdata(host) ((struct ip22_hostdata *)((host)->hostdata))

	struct hpc_chunk {
	struct hpc_dma_desc desc;
	u32 _padding; /* align to quadword boundary */
	};

	/* space for hpc dma descriptors */
	#define HPC_DMA_SIZE PAGE_SIZE

	#define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)

	static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
	{
	struct Scsi_Host * host = dev_id;
	unsigned long flags;

	spin_lock_irqsave(host->host_lock, flags);
	wd33c93_intr(host);
	spin_unlock_irqrestore(host->host_lock, flags);

	return IRQ_HANDLED;
	}

	static inline
	void fill_hpc_entries(struct ip22_hostdata hd, struct scsi_cmnd cmd, int din)
	{
	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
	unsigned long len = scsi_pointer->this_residual;
	void *addr = scsi_pointer->ptr;
	dma_addr_t physaddr;
	unsigned long count;
	struct hpc_chunk *hcp;

	physaddr = dma_map_single(hd->dev, addr, len, DMA_DIR(din));
	scsi_pointer->dma_handle = physaddr;
	hcp = hd->cpu;

	while (len) {
	/*
	* even cntinfo could be up to 16383, without
	* magic only 8192 works correctly
	*/
	count = len > 8192 ? 8192 : len;
	hcp->desc.pbuf = physaddr;
	hcp->desc.cntinfo = count;
	hcp++;
	len -= count;
	physaddr += count;
	}

	/*
	* To make sure, if we trip an HPC bug, that we transfer every single
	* byte, we tag on an extra zero length dma descriptor at the end of
	* the chain.
	*/
	hcp->desc.pbuf = 0;
	hcp->desc.cntinfo = HPCDMA_EOX;
	dma_sync_single_for_device(hd->dev, hd->dma,
	(unsigned long)(hcp + 1) - (unsigned long)hd->cpu,
	DMA_TO_DEVICE);
	}

	static int dma_setup(struct scsi_cmnd *cmd, int datainp)
	{
	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
	struct ip22_hostdata *hdata = host_to_hostdata(cmd->device->host);
	struct hpc3_scsiregs *hregs =
	(struct hpc3_scsiregs *) cmd->device->host->base;

	pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hdata->cpu);

	hdata->wh.dma_dir = datainp;

	/*
	* wd33c93 shouldn't pass us bogus dma_setups, but it does:-( The
	* other wd33c93 drivers deal with it the same way (which isn't that
	* obvious). IMHO a better fix would be, not to do these dma setups
	* in the first place.
	*/
	if (scsi_pointer->ptr == NULL \|\| scsi_pointer->this_residual == 0)
	return 1;

	fill_hpc_entries(hdata, cmd, datainp);

	pr_debug(" HPCGO\n");

	/* Start up the HPC. */
	hregs->ndptr = hdata->dma;
	if (datainp)
	hregs->ctrl = HPC3_SCTRL_ACTIVE;
	else
	hregs->ctrl = HPC3_SCTRL_ACTIVE \| HPC3_SCTRL_DIR;

	return 0;
	}

	static void dma_stop(struct Scsi_Host instance, struct scsi_cmnd SCpnt,
	int status)
	{
	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
	struct ip22_hostdata *hdata = host_to_hostdata(instance);
	struct hpc3_scsiregs *hregs;

	if (!SCpnt)
	return;

	if (scsi_pointer->ptr == NULL \|\| scsi_pointer->this_residual == 0)
	return;

	hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;

	pr_debug("dma_stop: status<%d> ", status);

	/* First stop the HPC and flush it's FIFO. */
	if (hdata->wh.dma_dir) {
	hregs->ctrl \|= HPC3_SCTRL_FLUSH;
	while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
	barrier();
	}
	hregs->ctrl = 0;
	dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
	scsi_pointer->this_residual,
	DMA_DIR(hdata->wh.dma_dir));

	pr_debug("\n");
	}

	void sgiwd93_reset(unsigned long base)
	{
	struct hpc3_scsiregs hregs = (struct hpc3_scsiregs ) base;

	hregs->ctrl = HPC3_SCTRL_CRESET;
	udelay(50);
	hregs->ctrl = 0;
	}
	EXPORT_SYMBOL_GPL(sgiwd93_reset);

	static inline void init_hpc_chain(struct ip22_hostdata *hdata)
	{
	struct hpc_chunk hcp = (struct hpc_chunk )hdata->cpu;
	dma_addr_t dma = hdata->dma;
	unsigned long start, end;

	start = (unsigned long) hcp;
	end = start + HPC_DMA_SIZE;
	while (start < end) {
	hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk));
	hcp->desc.cntinfo = HPCDMA_EOX;
	hcp++;
	dma += sizeof(struct hpc_chunk);
	start += sizeof(struct hpc_chunk);
	}
	hcp--;
	hcp->desc.pnext = hdata->dma;
	}

	/*
	* Kludge alert - the SCSI code calls the abort and reset method with int
	* arguments not with pointers. So this is going to blow up beautyfully
	* on 64-bit systems with memory outside the compat address spaces.
	*/
	static const struct scsi_host_template sgiwd93_template = {
	.module = THIS_MODULE,
	.proc_name = "SGIWD93",
	.name = "SGI WD93",
	.queuecommand = wd33c93_queuecommand,
	.eh_abort_handler = wd33c93_abort,
	.eh_host_reset_handler = wd33c93_host_reset,
	.can_queue = 16,
	.this_id = 7,
	.sg_tablesize = SG_ALL,
	.cmd_per_lun = 8,
	.dma_boundary = PAGE_SIZE - 1,
	.cmd_size = sizeof(struct scsi_pointer),
	};

	static int sgiwd93_probe(struct platform_device *pdev)
	{
	struct sgiwd93_platform_data *pd = pdev->dev.platform_data;
	unsigned char *wdregs = pd->wdregs;
	struct hpc3_scsiregs *hregs = pd->hregs;
	struct ip22_hostdata *hdata;
	struct Scsi_Host *host;
	wd33c93_regs regs;
	unsigned int unit = pd->unit;
	unsigned int irq = pd->irq;
	int err;

	host = scsi_host_alloc(&sgiwd93_template, sizeof(struct ip22_hostdata));
	if (!host) {
	err = -ENOMEM;
	goto out;
	}

	host->base = (unsigned long) hregs;
	host->irq = irq;

	hdata = host_to_hostdata(host);
	hdata->dev = &pdev->dev;
	hdata->cpu = dma_alloc_noncoherent(&pdev->dev, HPC_DMA_SIZE,
	&hdata->dma, DMA_TO_DEVICE, GFP_KERNEL);
	if (!hdata->cpu) {
	printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
	"host %d buffer.\n", unit);
	err = -ENOMEM;
	goto out_put;
	}

	init_hpc_chain(hdata);

	regs.SASR = wdregs + 3;
	regs.SCMD = wdregs + 7;

	hdata->wh.no_sync = 0;
	hdata->wh.fast = 1;
	hdata->wh.dma_mode = CTRL_BURST;

	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_MHZ(20));

	err = request_irq(irq, sgiwd93_intr, 0, "SGI WD93", host);
	if (err) {
	printk(KERN_WARNING "sgiwd93: Could not register irq %d "
	"for host %d.\n", irq, unit);
	goto out_free;
	}

	platform_set_drvdata(pdev, host);

	err = scsi_add_host(host, NULL);
	if (err)
	goto out_irq;

	scsi_scan_host(host);

	return 0;

	out_irq:
	free_irq(irq, host);
	out_free:
	dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
	DMA_TO_DEVICE);
	out_put:
	scsi_host_put(host);
	out:

	return err;
	}

	static void sgiwd93_remove(struct platform_device *pdev)
	{
	struct Scsi_Host *host = platform_get_drvdata(pdev);
	struct ip22_hostdata hdata = (struct ip22_hostdata ) host->hostdata;
	struct sgiwd93_platform_data *pd = pdev->dev.platform_data;

	scsi_remove_host(host);
	free_irq(pd->irq, host);
	dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
	DMA_TO_DEVICE);
	scsi_host_put(host);
	}

	static struct platform_driver sgiwd93_driver = {
	.probe = sgiwd93_probe,
	.remove_new = sgiwd93_remove,
	.driver = {
	.name = "sgiwd93",
	}
	};

	static int __init sgiwd93_module_init(void)
	{
	return platform_driver_register(&sgiwd93_driver);
	}

	static void __exit sgiwd93_module_exit(void)
	{
	return platform_driver_unregister(&sgiwd93_driver);
	}

	module_init(sgiwd93_module_init);
	module_exit(sgiwd93_module_exit);

	MODULE_DESCRIPTION("SGI WD33C93 driver");
	MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:sgiwd93");