xref: /linux/drivers/scsi/sgiwd93.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
7  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
8  * Copyright (C) 2001 Florian Lohoff (flo@rfc822.org)
9  * Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
10  *
11  * (In all truth, Jed Schimmel wrote all this code.)
12  */
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/types.h>
16 #include <linux/mm.h>
17 #include <linux/blkdev.h>
18 #include <linux/version.h>
19 #include <linux/delay.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/spinlock.h>
22 
23 #include <asm/page.h>
24 #include <asm/pgtable.h>
25 #include <asm/sgialib.h>
26 #include <asm/sgi/sgi.h>
27 #include <asm/sgi/mc.h>
28 #include <asm/sgi/hpc3.h>
29 #include <asm/sgi/ip22.h>
30 #include <asm/irq.h>
31 #include <asm/io.h>
32 
33 #include "scsi.h"
34 #include <scsi/scsi_host.h>
35 #include "wd33c93.h"
36 
37 #include <linux/stat.h>
38 
39 #if 0
40 #define DPRINTK(args...)	printk(args)
41 #else
42 #define DPRINTK(args...)
43 #endif
44 
45 #define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))
46 
47 struct ip22_hostdata {
48 	struct WD33C93_hostdata wh;
49 	struct hpc_data {
50 		dma_addr_t      dma;
51 		void            * cpu;
52 	} hd;
53 };
54 
55 struct hpc_chunk {
56 	struct hpc_dma_desc desc;
57 	u32 _padding;	/* align to quadword boundary */
58 };
59 
60 struct Scsi_Host *sgiwd93_host;
61 struct Scsi_Host *sgiwd93_host1;
62 
63 /* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
64 static inline void write_wd33c93_count(const wd33c93_regs regs,
65                                       unsigned long value)
66 {
67 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
68 	mb();
69 	*regs.SCMD = ((value >> 16) & 0xff);
70 	*regs.SCMD = ((value >>  8) & 0xff);
71 	*regs.SCMD = ((value >>  0) & 0xff);
72 	mb();
73 }
74 
75 static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
76 {
77 	unsigned long value;
78 
79 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
80 	mb();
81 	value =  ((*regs.SCMD & 0xff) << 16);
82 	value |= ((*regs.SCMD & 0xff) <<  8);
83 	value |= ((*regs.SCMD & 0xff) <<  0);
84 	mb();
85 	return value;
86 }
87 
88 static irqreturn_t sgiwd93_intr(int irq, void *dev_id, struct pt_regs *regs)
89 {
90 	struct Scsi_Host * host = (struct Scsi_Host *) dev_id;
91 	unsigned long flags;
92 
93 	spin_lock_irqsave(host->host_lock, flags);
94 	wd33c93_intr(host);
95 	spin_unlock_irqrestore(host->host_lock, flags);
96 
97 	return IRQ_HANDLED;
98 }
99 
100 static inline
101 void fill_hpc_entries(struct hpc_chunk *hcp, Scsi_Cmnd *cmd, int datainp)
102 {
103 	unsigned long len = cmd->SCp.this_residual;
104 	void *addr = cmd->SCp.ptr;
105 	dma_addr_t physaddr;
106 	unsigned long count;
107 
108 	physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
109 	cmd->SCp.dma_handle = physaddr;
110 
111 	while (len) {
112 		/*
113 		 * even cntinfo could be up to 16383, without
114 		 * magic only 8192 works correctly
115 		 */
116 		count = len > 8192 ? 8192 : len;
117 		hcp->desc.pbuf = physaddr;
118 		hcp->desc.cntinfo = count;
119 		hcp++;
120 		len -= count;
121 		physaddr += count;
122 	}
123 
124 	/*
125 	 * To make sure, if we trip an HPC bug, that we transfer every single
126 	 * byte, we tag on an extra zero length dma descriptor at the end of
127 	 * the chain.
128 	 */
129 	hcp->desc.pbuf = 0;
130 	hcp->desc.cntinfo = HPCDMA_EOX;
131 }
132 
133 static int dma_setup(Scsi_Cmnd *cmd, int datainp)
134 {
135 	struct ip22_hostdata *hdata = HDATA(cmd->device->host);
136 	struct hpc3_scsiregs *hregs =
137 		(struct hpc3_scsiregs *) cmd->device->host->base;
138 	struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
139 
140 	DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
141 
142 	hdata->wh.dma_dir = datainp;
143 
144 	/*
145 	 * wd33c93 shouldn't pass us bogus dma_setups, but it does:-(  The
146 	 * other wd33c93 drivers deal with it the same way (which isn't that
147 	 * obvious).  IMHO a better fix would be, not to do these dma setups
148 	 * in the first place.
149 	 */
150 	if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
151 		return 1;
152 
153 	fill_hpc_entries(hcp, cmd, datainp);
154 
155 	DPRINTK(" HPCGO\n");
156 
157 	/* Start up the HPC. */
158 	hregs->ndptr = hdata->hd.dma;
159 	if (datainp)
160 		hregs->ctrl = HPC3_SCTRL_ACTIVE;
161 	else
162 		hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
163 
164 	return 0;
165 }
166 
167 static void dma_stop(struct Scsi_Host *instance, Scsi_Cmnd *SCpnt,
168 		     int status)
169 {
170 	struct ip22_hostdata *hdata = HDATA(instance);
171 	struct hpc3_scsiregs *hregs;
172 
173 	if (!SCpnt)
174 		return;
175 
176 	hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
177 
178 	DPRINTK("dma_stop: status<%d> ", status);
179 
180 	/* First stop the HPC and flush it's FIFO. */
181 	if (hdata->wh.dma_dir) {
182 		hregs->ctrl |= HPC3_SCTRL_FLUSH;
183 		while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
184 			barrier();
185 	}
186 	hregs->ctrl = 0;
187 	dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
188 	                 SCpnt->sc_data_direction);
189 
190 	DPRINTK("\n");
191 }
192 
193 void sgiwd93_reset(unsigned long base)
194 {
195 	struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
196 
197 	hregs->ctrl = HPC3_SCTRL_CRESET;
198 	udelay(50);
199 	hregs->ctrl = 0;
200 }
201 
202 static inline void init_hpc_chain(struct hpc_data *hd)
203 {
204 	struct hpc_chunk *hcp = (struct hpc_chunk *) hd->cpu;
205 	struct hpc_chunk *dma = (struct hpc_chunk *) hd->dma;
206 	unsigned long start, end;
207 
208 	start = (unsigned long) hcp;
209 	end = start + PAGE_SIZE;
210 	while (start < end) {
211 		hcp->desc.pnext = (u32) (dma + 1);
212 		hcp->desc.cntinfo = HPCDMA_EOX;
213 		hcp++; dma++;
214 		start += sizeof(struct hpc_chunk);
215 	};
216 	hcp--;
217 	hcp->desc.pnext = hd->dma;
218 }
219 
220 static struct Scsi_Host * __init sgiwd93_setup_scsi(
221 	Scsi_Host_Template *SGIblows, int unit, int irq,
222 	struct hpc3_scsiregs *hregs, unsigned char *wdregs)
223 {
224 	struct ip22_hostdata *hdata;
225 	struct Scsi_Host *host;
226 	wd33c93_regs regs;
227 
228 	host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
229 	if (!host)
230 		return NULL;
231 
232 	host->base = (unsigned long) hregs;
233 	host->irq = irq;
234 
235 	hdata = HDATA(host);
236 	hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
237 	                                   GFP_KERNEL);
238 	if (!hdata->hd.cpu) {
239 		printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
240 		       "host %d buffer.\n", unit);
241 		goto out_unregister;
242 	}
243 	init_hpc_chain(&hdata->hd);
244 
245 	regs.SASR = wdregs + 3;
246 	regs.SCMD = wdregs + 7;
247 
248 	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);
249 
250 	hdata->wh.no_sync = 0;
251 
252 	if (request_irq(irq, sgiwd93_intr, 0, "SGI WD93", (void *) host)) {
253 		printk(KERN_WARNING "sgiwd93: Could not register irq %d "
254 		       "for host %d.\n", irq, unit);
255 		goto out_free;
256 	}
257 	return host;
258 
259 out_free:
260 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
261 	wd33c93_release();
262 
263 out_unregister:
264 	scsi_unregister(host);
265 
266 	return NULL;
267 }
268 
269 int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
270 {
271 	int found = 0;
272 
273 	SGIblows->proc_name = "SGIWD93";
274 	sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
275 	                                  &hpc3c0->scsi_chan0,
276 	                                  (unsigned char *)hpc3c0->scsi0_ext);
277 	if (sgiwd93_host)
278 		found++;
279 
280 	/* Set up second controller on the Indigo2 */
281 	if (ip22_is_fullhouse()) {
282 		sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
283 		                          &hpc3c0->scsi_chan1,
284 		                          (unsigned char *)hpc3c0->scsi1_ext);
285 		if (sgiwd93_host1)
286 			found++;
287 	}
288 
289 	return found;
290 }
291 
292 int sgiwd93_release(struct Scsi_Host *instance)
293 {
294 	struct ip22_hostdata *hdata = HDATA(instance);
295 	int irq = 0;
296 
297 	if (sgiwd93_host && sgiwd93_host == instance)
298 		irq = SGI_WD93_0_IRQ;
299 	else if (sgiwd93_host1 && sgiwd93_host1 == instance)
300 		irq = SGI_WD93_1_IRQ;
301 
302 	free_irq(irq, sgiwd93_intr);
303 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
304 	wd33c93_release();
305 
306 	return 1;
307 }
308 
309 static int sgiwd93_bus_reset(Scsi_Cmnd *cmd)
310 {
311 	/* FIXME perform bus-specific reset */
312 
313 	/* FIXME 2: kill this function, and let midlayer fallback
314 	   to the same result, calling wd33c93_host_reset() */
315 
316 	spin_lock_irq(cmd->device->host->host_lock);
317 	wd33c93_host_reset(cmd);
318 	spin_unlock_irq(cmd->device->host->host_lock);
319 
320 	return SUCCESS;
321 }
322 
323 /*
324  * Kludge alert - the SCSI code calls the abort and reset method with int
325  * arguments not with pointers.  So this is going to blow up beautyfully
326  * on 64-bit systems with memory outside the compat address spaces.
327  */
328 static Scsi_Host_Template driver_template = {
329 	.proc_name		= "SGIWD93",
330 	.name			= "SGI WD93",
331 	.detect			= sgiwd93_detect,
332 	.release		= sgiwd93_release,
333 	.queuecommand		= wd33c93_queuecommand,
334 	.eh_abort_handler	= wd33c93_abort,
335 	.eh_bus_reset_handler	= sgiwd93_bus_reset,
336 	.eh_host_reset_handler	= wd33c93_host_reset,
337 	.can_queue		= 16,
338 	.this_id		= 7,
339 	.sg_tablesize		= SG_ALL,
340 	.cmd_per_lun		= 8,
341 	.use_clustering		= DISABLE_CLUSTERING,
342 };
343 #include "scsi_module.c"
344