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 (dm@engr.sgi.com)
  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
  * Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
  * Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
  *
  * (In all truth, Jed Schimmel wrote all this code.)
  */
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/types.h>
 #include <linux/mm.h>
 #include <linux/blkdev.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
 #include <linux/spinlock.h>

 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/sgialib.h>
 #include <asm/sgi/sgi.h>
 #include <asm/sgi/mc.h>
 #include <asm/sgi/hpc3.h>
 #include <asm/sgi/ip22.h>
 #include <asm/irq.h>
 #include <asm/io.h>

 #include "scsi.h"
 #include <scsi/scsi_host.h>
 #include "wd33c93.h"

 #include <linux/stat.h>

 #if 0
 #define DPRINTK(args...)	printk(args)
 #else
 #define DPRINTK(args...)
 #endif

 #define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))

 struct ip22_hostdata {
 	struct WD33C93_hostdata wh;
 	struct hpc_data {
 		dma_addr_t      dma;
 		void            * cpu;
 	} hd;
 };

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

 struct Scsi_Host *sgiwd93_host;
 struct Scsi_Host *sgiwd93_host1;

 /* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
 static inline void write_wd33c93_count(const wd33c93_regs regs,
                                       unsigned long value)
 {
 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
 	mb();
 	*regs.SCMD = ((value >> 16) & 0xff);
 	*regs.SCMD = ((value >>  8) & 0xff);
 	*regs.SCMD = ((value >>  0) & 0xff);
 	mb();
 }

 static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
 {
 	unsigned long value;

 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
 	mb();
 	value =  ((*regs.SCMD & 0xff) << 16);
 	value |= ((*regs.SCMD & 0xff) <<  8);
 	value |= ((*regs.SCMD & 0xff) <<  0);
 	mb();
 	return value;
 }

 static irqreturn_t sgiwd93_intr(int irq, void *dev_id, struct pt_regs *regs)
 {
 	struct Scsi_Host * host = (struct Scsi_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 hpc_chunk *hcp, Scsi_Cmnd *cmd, int datainp)
 {
 	unsigned long len = cmd->SCp.this_residual;
 	void *addr = cmd->SCp.ptr;
 	dma_addr_t physaddr;
 	unsigned long count;

 	physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
 	cmd->SCp.dma_handle = physaddr;

 	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;
 }

 static int dma_setup(Scsi_Cmnd *cmd, int datainp)
 {
 	struct ip22_hostdata *hdata = HDATA(cmd->device->host);
 	struct hpc3_scsiregs *hregs =
 		(struct hpc3_scsiregs *) cmd->device->host->base;
 	struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;

 	DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);

 	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 (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
 		return 1;

 	fill_hpc_entries(hcp, cmd, datainp);

 	DPRINTK(" HPCGO\n");

 	/* Start up the HPC. */
 	hregs->ndptr = hdata->hd.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, Scsi_Cmnd *SCpnt,
 		     int status)
 {
 	struct ip22_hostdata *hdata = HDATA(instance);
 	struct hpc3_scsiregs *hregs;

 	if (!SCpnt)
 		return;

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

 	DPRINTK("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(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
 	                 SCpnt->sc_data_direction);

 	DPRINTK("\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;
 }

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

 	start = (unsigned long) hcp;
 	end = start + PAGE_SIZE;
 	while (start < end) {
 		hcp->desc.pnext = (u32) (dma + 1);
 		hcp->desc.cntinfo = HPCDMA_EOX;
 		hcp++; dma++;
 		start += sizeof(struct hpc_chunk);
 	};
 	hcp--;
 	hcp->desc.pnext = hd->dma;
 }

 static struct Scsi_Host * __init sgiwd93_setup_scsi(
 	Scsi_Host_Template *SGIblows, int unit, int irq,
 	struct hpc3_scsiregs *hregs, unsigned char *wdregs)
 {
 	struct ip22_hostdata *hdata;
 	struct Scsi_Host *host;
 	wd33c93_regs regs;

 	host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
 	if (!host)
 		return NULL;

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

 	hdata = HDATA(host);
 	hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
 	                                   GFP_KERNEL);
 	if (!hdata->hd.cpu) {
 		printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
 		       "host %d buffer.\n", unit);
 		goto out_unregister;
 	}
 	init_hpc_chain(&hdata->hd);

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

 	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);

 	hdata->wh.no_sync = 0;

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

 out_free:
 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 	wd33c93_release();

 out_unregister:
 	scsi_unregister(host);

 	return NULL;
 }

 int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
 {
 	int found = 0;

 	SGIblows->proc_name = "SGIWD93";
 	sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
 	                                  &hpc3c0->scsi_chan0,
 	                                  (unsigned char *)hpc3c0->scsi0_ext);
 	if (sgiwd93_host)
 		found++;

 	/* Set up second controller on the Indigo2 */
 	if (ip22_is_fullhouse()) {
 		sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
 		                          &hpc3c0->scsi_chan1,
 		                          (unsigned char *)hpc3c0->scsi1_ext);
 		if (sgiwd93_host1)
 			found++;
 	}

 	return found;
 }

 int sgiwd93_release(struct Scsi_Host *instance)
 {
 	struct ip22_hostdata *hdata = HDATA(instance);
 	int irq = 0;

 	if (sgiwd93_host && sgiwd93_host == instance)
 		irq = SGI_WD93_0_IRQ;
 	else if (sgiwd93_host1 && sgiwd93_host1 == instance)
 		irq = SGI_WD93_1_IRQ;

 	free_irq(irq, sgiwd93_intr);
 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
 	wd33c93_release();

 	return 1;
 }

 static int sgiwd93_bus_reset(Scsi_Cmnd *cmd)
 {
 	/* FIXME perform bus-specific reset */

 	/* FIXME 2: kill this function, and let midlayer fallback
 	   to the same result, calling wd33c93_host_reset() */

 	spin_lock_irq(cmd->device->host->host_lock);
 	wd33c93_host_reset(cmd);
 	spin_unlock_irq(cmd->device->host->host_lock);

 	return SUCCESS;
 }

 /*
  * 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 Scsi_Host_Template driver_template = {
 	.proc_name		= "SGIWD93",
 	.name			= "SGI WD93",
 	.detect			= sgiwd93_detect,
 	.release		= sgiwd93_release,
 	.queuecommand		= wd33c93_queuecommand,
 	.eh_abort_handler	= wd33c93_abort,
 	.eh_bus_reset_handler	= sgiwd93_bus_reset,
 	.eh_host_reset_handler	= wd33c93_host_reset,
 	.can_queue		= 16,
 	.this_id		= 7,
 	.sg_tablesize		= SG_ALL,
 	.cmd_per_lun		= 8,
 	.use_clustering		= DISABLE_CLUSTERING,
 };
 #include "scsi_module.c"
	/*
	* 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 (dm@engr.sgi.com)
	* Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
	* Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
	* Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
	*
	* (In all truth, Jed Schimmel wrote all this code.)
	*/
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/types.h>
	#include <linux/mm.h>
	#include <linux/blkdev.h>
	#include <linux/delay.h>
	#include <linux/dma-mapping.h>
	#include <linux/spinlock.h>

	#include <asm/page.h>
	#include <asm/pgtable.h>
	#include <asm/sgialib.h>
	#include <asm/sgi/sgi.h>
	#include <asm/sgi/mc.h>
	#include <asm/sgi/hpc3.h>
	#include <asm/sgi/ip22.h>
	#include <asm/irq.h>
	#include <asm/io.h>

	#include "scsi.h"
	#include <scsi/scsi_host.h>
	#include "wd33c93.h"

	#include <linux/stat.h>

	#if 0
	#define DPRINTK(args...) printk(args)
	#else
	#define DPRINTK(args...)
	#endif

	#define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))

	struct ip22_hostdata {
	struct WD33C93_hostdata wh;
	struct hpc_data {
	dma_addr_t dma;
	void * cpu;
	} hd;
	};

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

	struct Scsi_Host *sgiwd93_host;
	struct Scsi_Host *sgiwd93_host1;

	/* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
	static inline void write_wd33c93_count(const wd33c93_regs regs,
	unsigned long value)
	{
	*regs.SASR = WD_TRANSFER_COUNT_MSB;
	mb();
	*regs.SCMD = ((value >> 16) & 0xff);
	*regs.SCMD = ((value >> 8) & 0xff);
	*regs.SCMD = ((value >> 0) & 0xff);
	mb();
	}

	static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
	{
	unsigned long value;

	*regs.SASR = WD_TRANSFER_COUNT_MSB;
	mb();
	value = ((*regs.SCMD & 0xff) << 16);
	value \|= ((*regs.SCMD & 0xff) << 8);
	value \|= ((*regs.SCMD & 0xff) << 0);
	mb();
	return value;
	}

	static irqreturn_t sgiwd93_intr(int irq, void dev_id, struct pt_regs regs)
	{
	struct Scsi_Host * host = (struct Scsi_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 hpc_chunk hcp, Scsi_Cmnd cmd, int datainp)
	{
	unsigned long len = cmd->SCp.this_residual;
	void *addr = cmd->SCp.ptr;
	dma_addr_t physaddr;
	unsigned long count;

	physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
	cmd->SCp.dma_handle = physaddr;

	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;
	}

	static int dma_setup(Scsi_Cmnd *cmd, int datainp)
	{
	struct ip22_hostdata *hdata = HDATA(cmd->device->host);
	struct hpc3_scsiregs *hregs =
	(struct hpc3_scsiregs *) cmd->device->host->base;
	struct hpc_chunk hcp = (struct hpc_chunk ) hdata->hd.cpu;

	DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);

	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 (cmd->SCp.ptr == NULL \|\| cmd->SCp.this_residual == 0)
	return 1;

	fill_hpc_entries(hcp, cmd, datainp);

	DPRINTK(" HPCGO\n");

	/* Start up the HPC. */
	hregs->ndptr = hdata->hd.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, Scsi_Cmnd SCpnt,
	int status)
	{
	struct ip22_hostdata *hdata = HDATA(instance);
	struct hpc3_scsiregs *hregs;

	if (!SCpnt)
	return;

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

	DPRINTK("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(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
	SCpnt->sc_data_direction);

	DPRINTK("\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;
	}

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

	start = (unsigned long) hcp;
	end = start + PAGE_SIZE;
	while (start < end) {
	hcp->desc.pnext = (u32) (dma + 1);
	hcp->desc.cntinfo = HPCDMA_EOX;
	hcp++; dma++;
	start += sizeof(struct hpc_chunk);
	};
	hcp--;
	hcp->desc.pnext = hd->dma;
	}

	static struct Scsi_Host * __init sgiwd93_setup_scsi(
	Scsi_Host_Template *SGIblows, int unit, int irq,
	struct hpc3_scsiregs hregs, unsigned char wdregs)
	{
	struct ip22_hostdata *hdata;
	struct Scsi_Host *host;
	wd33c93_regs regs;

	host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
	if (!host)
	return NULL;

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

	hdata = HDATA(host);
	hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
	GFP_KERNEL);
	if (!hdata->hd.cpu) {
	printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
	"host %d buffer.\n", unit);
	goto out_unregister;
	}
	init_hpc_chain(&hdata->hd);

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

	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);

	hdata->wh.no_sync = 0;

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

	out_free:
	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
	wd33c93_release();

	out_unregister:
	scsi_unregister(host);

	return NULL;
	}

	int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
	{
	int found = 0;

	SGIblows->proc_name = "SGIWD93";
	sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
	&hpc3c0->scsi_chan0,
	(unsigned char *)hpc3c0->scsi0_ext);
	if (sgiwd93_host)
	found++;

	/* Set up second controller on the Indigo2 */
	if (ip22_is_fullhouse()) {
	sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
	&hpc3c0->scsi_chan1,
	(unsigned char *)hpc3c0->scsi1_ext);
	if (sgiwd93_host1)
	found++;
	}

	return found;
	}

	int sgiwd93_release(struct Scsi_Host *instance)
	{
	struct ip22_hostdata *hdata = HDATA(instance);
	int irq = 0;

	if (sgiwd93_host && sgiwd93_host == instance)
	irq = SGI_WD93_0_IRQ;
	else if (sgiwd93_host1 && sgiwd93_host1 == instance)
	irq = SGI_WD93_1_IRQ;

	free_irq(irq, sgiwd93_intr);
	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
	wd33c93_release();

	return 1;
	}

	static int sgiwd93_bus_reset(Scsi_Cmnd *cmd)
	{
	/* FIXME perform bus-specific reset */

	/* FIXME 2: kill this function, and let midlayer fallback
	to the same result, calling wd33c93_host_reset() */

	spin_lock_irq(cmd->device->host->host_lock);
	wd33c93_host_reset(cmd);
	spin_unlock_irq(cmd->device->host->host_lock);

	return SUCCESS;
	}

	/*
	* 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 Scsi_Host_Template driver_template = {
	.proc_name = "SGIWD93",
	.name = "SGI WD93",
	.detect = sgiwd93_detect,
	.release = sgiwd93_release,
	.queuecommand = wd33c93_queuecommand,
	.eh_abort_handler = wd33c93_abort,
	.eh_bus_reset_handler = sgiwd93_bus_reset,
	.eh_host_reset_handler = wd33c93_host_reset,
	.can_queue = 16,
	.this_id = 7,
	.sg_tablesize = SG_ALL,
	.cmd_per_lun = 8,
	.use_clustering = DISABLE_CLUSTERING,
	};
	#include "scsi_module.c"