[PATCH] mips: sgiwd93 2.6 fixes and crapectomy

From: Ralf Baechle <ralf@linux-mips.org>

Get to work under 2.6 sorting out the giant mess this has been.  Further
cleanups would require a full crapectomy of wd33c93.c itself ...

drivers/scsi/sgiwd93.c

 /*
- * sgiwd93.c: SGI WD93 scsi driver.
+ * 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)
- *		 1999 Andrew R. Baker (andrewb@uab.edu)
- *		      - Support for 2nd SCSI controller on Indigo2
- *		 2001 Florian Lohoff (flo@rfc822.org)
- *		      - Delete HPC scatter gather (Read corruption on 
- *		        multiple disks)
- *		      - Cleanup wback cache handling
+ * 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/version.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/sgimc.h>
-#include <asm/sgi/sgihpc.h>
-#include <asm/sgi/sgint23.h>
+#include <asm/sgi/mc.h>
+#include <asm/sgi/hpc3.h>
+#include <asm/sgi/ip22.h>
 #include <asm/irq.h>
 #include <asm/io.h>
 
@@ -37,95 +37,130 @@
 
 #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 = NULL;
-struct Scsi_Host *sgiwd93_host1 = NULL;
+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();
+}
 
-/* XXX woof! */
-static void sgiwd93_intr(int irq, void *dev_id, struct pt_regs *regs)
+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;
-	struct Scsi_Host *dev = dev_id;
 
-	spin_lock_irqsave(dev->host_lock, flags);
-	wd33c93_intr((struct Scsi_Host *) dev_id);
-	spin_unlock_irqrestore(dev->host_lock, flags);
-}
+	spin_lock_irqsave(host->host_lock, flags);
+	wd33c93_intr(host);
+	spin_unlock_irqrestore(host->host_lock, flags);
 
-#undef DEBUG_DMA
+	return IRQ_HANDLED;
+}
 
 static inline
-void fill_hpc_entries (struct hpc_chunk **hcp, char *addr, unsigned long len)
+void fill_hpc_entries(struct hpc_chunk *hcp, Scsi_Cmnd *cmd, int datainp)
 {
-	unsigned long physaddr;
+	unsigned long len = cmd->SCp.this_residual;
+	void *addr = cmd->SCp.ptr;
+	dma_addr_t physaddr;
 	unsigned long count;
 
-	physaddr = PHYSADDR(addr);
+	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)++;
+		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 WD33C93_hostdata *hdata = (struct WD33C93_hostdata *)cmd->host->hostdata;
-	struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) cmd->host->base;
-	struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->dma_bounce_buffer;
+	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;
 
-#ifdef DEBUG_DMA
-	printk("dma_setup: datainp<%d> hcp<%p> ",
-	       datainp, hcp);
-#endif
+	DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
 
-	hdata->dma_dir = datainp;
+	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
+	 * 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)
+	if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
 		return 1;
 
-	fill_hpc_entries (&hcp, cmd->SCp.ptr,cmd->SCp.this_residual);
+	fill_hpc_entries(hcp, cmd, datainp);
 
-	/* 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);
-
-#ifdef DEBUG_DMA
-	printk(" HPCGO\n");
-#endif
+	DPRINTK(" HPCGO\n");
 
 	/* Start up the HPC. */
-	hregs->ndptr = PHYSADDR(hdata->dma_bounce_buffer);
-	if(datainp) {
-		dma_cache_inv((unsigned long) cmd->SCp.ptr, cmd->SCp.this_residual);
-		hregs->ctrl = (HPC3_SCTRL_ACTIVE);
-	} else {
-		dma_cache_wback_inv((unsigned long) cmd->SCp.ptr, cmd->SCp.this_residual);
-		hregs->ctrl = (HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR);
-	}
+	hregs->ndptr = hdata->hd.dma;
+	if (datainp)
+		hregs->ctrl = HPC3_SCTRL_ACTIVE;
+	else
+		hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
 
 	return 0;
 }
@@ -133,29 +168,27 @@ static int dma_setup(Scsi_Cmnd *cmd, int datainp)
 static void dma_stop(struct Scsi_Host *instance, Scsi_Cmnd *SCpnt,
 		     int status)
 {
-	struct WD33C93_hostdata *hdata = (struct WD33C93_hostdata *)instance->hostdata;
+	struct ip22_hostdata *hdata = HDATA(instance);
 	struct hpc3_scsiregs *hregs;
 
 	if (!SCpnt)
 		return;
 
-	hregs = (struct hpc3_scsiregs *) SCpnt->host->base;
+	hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
 
-#ifdef DEBUG_DMA
-	printk("dma_stop: status<%d> ", status);
-#endif
+	DPRINTK("dma_stop: status<%d> ", status);
 
 	/* First stop the HPC and flush it's FIFO. */
-	if(hdata->dma_dir) {
+	if (hdata->wh.dma_dir) {
 		hregs->ctrl |= HPC3_SCTRL_FLUSH;
-		while(hregs->ctrl & HPC3_SCTRL_ACTIVE)
+		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);
 
-#ifdef DEBUG_DMA
-	printk("\n");
-#endif
+	DPRINTK("\n");
 }
 
 void sgiwd93_reset(unsigned long base)
@@ -163,138 +196,138 @@ void sgiwd93_reset(unsigned long base)
 	struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
 
 	hregs->ctrl = HPC3_SCTRL_CRESET;
-	udelay (50);
+	udelay(50);
 	hregs->ctrl = 0;
 }
 
-static inline void init_hpc_chain(uchar *buf)
+static inline void init_hpc_chain(struct hpc_data *hd)
 {
-	struct hpc_chunk *hcp = (struct hpc_chunk *) buf;
+	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) buf;
+	start = (unsigned long) hcp;
 	end = start + PAGE_SIZE;
-	while(start < end) {
-		hcp->desc.pnext = PHYSADDR((hcp + 1));
+	while (start < end) {
+		hcp->desc.pnext = (u32) (dma + 1);
 		hcp->desc.cntinfo = HPCDMA_EOX;
-		hcp++;
+		hcp++; dma++;
 		start += sizeof(struct hpc_chunk);
 	};
 	hcp--;
-	hcp->desc.pnext = PHYSADDR(buf);
-
-	/* Force flush to memory */
-	dma_cache_wback_inv((unsigned long) buf, PAGE_SIZE);
+	hcp->desc.pnext = hd->dma;
 }
 
-int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
+static struct Scsi_Host * __init sgiwd93_setup_scsi(
+	Scsi_Host_Template *SGIblows, int unit, int irq,
+	struct hpc3_scsiregs *hregs, unsigned char *wdregs)
 {
-	static unsigned char called = 0;
-	struct hpc3_scsiregs *hregs = &hpc3c0->scsi_chan0;
-	struct hpc3_scsiregs *hregs1 = &hpc3c0->scsi_chan1;
-	struct WD33C93_hostdata *hdata;
-	struct WD33C93_hostdata *hdata1;
+	struct ip22_hostdata *hdata;
+	struct Scsi_Host *host;
 	wd33c93_regs regs;
-	uchar *buf;
-	
-	if(called)
-		return 0; /* Should bitch on the console about this... */
 
-	SGIblows->proc_name = "SGIWD93";
+	host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
+	if (!host)
+		return NULL;
 
-	sgiwd93_host = scsi_register(SGIblows, sizeof(struct WD33C93_hostdata));
-	if(sgiwd93_host == NULL)
-		return 0;
-	sgiwd93_host->base = (unsigned long) hregs;
-	sgiwd93_host->irq = SGI_WD93_0_IRQ;
+	host->base = (unsigned long) hregs;
+	host->irq = irq;
 
-	buf = (uchar *) get_zeroed_page(GFP_KERNEL);
-	if (!buf) {
-		printk(KERN_WARNING "sgiwd93: Could not allocate memory for host0 buffer.\n");
-		scsi_unregister(sgiwd93_host);
-		return 0;
+	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(buf);
+	init_hpc_chain(&hdata->hd);
 
-	/* HPC_SCSI_REG0 | 0x03 | KSEG1 */
-	regs.SASR = (unsigned char*) KSEG1ADDR (0x1fbc0003);
-	regs.SCMD = (unsigned char*) KSEG1ADDR (0x1fbc0007);
-	wd33c93_init(sgiwd93_host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);
+	regs.SASR = wdregs + 3;
+	regs.SCMD = wdregs + 7;
 
-	hdata = (struct WD33C93_hostdata *)sgiwd93_host->hostdata;
-	hdata->no_sync = 0;
-	hdata->dma_bounce_buffer = (uchar *) (KSEG1ADDR(buf));
+	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);
 
-	if (request_irq(SGI_WD93_0_IRQ, sgiwd93_intr, 0, "SGI WD93", (void *) sgiwd93_host)) {
-		printk(KERN_WARNING "sgiwd93: Could not register IRQ %d (for host 0).\n", SGI_WD93_0_IRQ);
-		wd33c93_release();
-		free_page((unsigned long)buf);
-		scsi_unregister(sgiwd93_host);
-		return 0;
-	}
-        /* set up second controller on the Indigo2 */
-	if(!sgi_guiness) {
-		sgiwd93_host1 = scsi_register(SGIblows, sizeof(struct WD33C93_hostdata));
-		if(sgiwd93_host1 != NULL)
-		{
-			sgiwd93_host1->base = (unsigned long) hregs1;
-			sgiwd93_host1->irq = SGI_WD93_1_IRQ;
-	
-			buf = (uchar *) get_zeroed_page(GFP_KERNEL);
-			if (!buf) {
-				printk(KERN_WARNING "sgiwd93: Could not allocate memory for host1 buffer.\n");
-				scsi_unregister(sgiwd93_host1);
-				called = 1;
-				return 1; /* We registered host0 so return success*/
+	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;
 	}
-			init_hpc_chain(buf);
+	return host;
 
-			/* HPC_SCSI_REG1 | 0x03 | KSEG1 */
-			regs.SASR = (unsigned char*) KSEG1ADDR(0x1fbc8003);
-			regs.SCMD = (unsigned char*) KSEG1ADDR(0x1fbc8007);
-			wd33c93_init(sgiwd93_host1, regs, dma_setup, dma_stop,
-			             WD33C93_FS_16_20);
+out_free:
+	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
+	wd33c93_release();
 
-			hdata1 = (struct WD33C93_hostdata *)sgiwd93_host1->hostdata;
-			hdata1->no_sync = 0;
-			hdata1->dma_bounce_buffer = (uchar *) (KSEG1ADDR(buf));
+out_unregister:
+	scsi_unregister(host);
 
-			if (request_irq(SGI_WD93_1_IRQ, sgiwd93_intr, 0, "SGI WD93", (void *) sgiwd93_host1)) {
-				printk(KERN_WARNING "sgiwd93: Could not allocate irq %d (for host1).\n", SGI_WD93_1_IRQ);
-				wd33c93_release();
-				free_page((unsigned long)buf);
-				scsi_unregister(sgiwd93_host1);
-				/* Fall through since host0 registered OK */
-			}
-		}
-	}
+	return NULL;
+}
 
-	called = 1;
+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 1; /* Found one. */
+	return found;
 }
 
 int sgiwd93_release(struct Scsi_Host *instance)
 {
-	free_irq(SGI_WD93_0_IRQ, sgiwd93_intr);
-	free_page(KSEG0ADDR(hdata->dma_bounce_buffer));
-	wd33c93_release();
-	if(!sgi_guiness) {
-		free_irq(SGI_WD93_1_IRQ, sgiwd93_intr);
-		free_page(KSEG0ADDR(hdata1->dma_bounce_buffer));
+	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 */
+	wd33c93_host_reset(cmd);
+	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,
-	.abort               = wd33c93_abort,
-	.reset               = wd33c93_reset,
+	.eh_abort_handler	= wd33c93_abort,
+	.eh_bus_reset_handler	= sgiwd93_bus_reset,
+	.eh_host_reset_handler	= wd33c93_host_reset,
 	.can_queue		= CAN_QUEUE,
 	.this_id		= 7,
 	.sg_tablesize		= SG_ALL,

drivers/scsi/sgiwd93.h

@@ -19,6 +19,6 @@ int sgiwd93_release(struct Scsi_Host *instance);
 const char *wd33c93_info(void);
 int wd33c93_queuecommand(Scsi_Cmnd *, void (*done)(Scsi_Cmnd *));
 int wd33c93_abort(Scsi_Cmnd *);
-int wd33c93_reset(Scsi_Cmnd *, unsigned int);
+int wd33c93_host_reset(Scsi_Cmnd * SCpnt);
 
 #endif /* !(_SGIWD93_H) */