xref: /openbmc/linux/drivers/scsi/sgiwd93.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 #include "sgiwd93.h"
37 
38 #include <linux/stat.h>
39 
40 #if 0
41 #define DPRINTK(args...)	printk(args)
42 #else
43 #define DPRINTK(args...)
44 #endif
45 
46 #define HDATA(ptr) ((struct ip22_hostdata *)((ptr)->hostdata))
47 
48 struct ip22_hostdata {
49 	struct WD33C93_hostdata wh;
50 	struct hpc_data {
51 		dma_addr_t      dma;
52 		void            * cpu;
53 	} hd;
54 };
55 
56 struct hpc_chunk {
57 	struct hpc_dma_desc desc;
58 	u32 _padding;	/* align to quadword boundary */
59 };
60 
61 struct Scsi_Host *sgiwd93_host;
62 struct Scsi_Host *sgiwd93_host1;
63 
64 /* Wuff wuff, wuff, wd33c93.c, wuff wuff, object oriented, bow wow. */
65 static inline void write_wd33c93_count(const wd33c93_regs regs,
66                                       unsigned long value)
67 {
68 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
69 	mb();
70 	*regs.SCMD = ((value >> 16) & 0xff);
71 	*regs.SCMD = ((value >>  8) & 0xff);
72 	*regs.SCMD = ((value >>  0) & 0xff);
73 	mb();
74 }
75 
76 static inline unsigned long read_wd33c93_count(const wd33c93_regs regs)
77 {
78 	unsigned long value;
79 
80 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
81 	mb();
82 	value =  ((*regs.SCMD & 0xff) << 16);
83 	value |= ((*regs.SCMD & 0xff) <<  8);
84 	value |= ((*regs.SCMD & 0xff) <<  0);
85 	mb();
86 	return value;
87 }
88 
89 static irqreturn_t sgiwd93_intr(int irq, void *dev_id, struct pt_regs *regs)
90 {
91 	struct Scsi_Host * host = (struct Scsi_Host *) dev_id;
92 	unsigned long flags;
93 
94 	spin_lock_irqsave(host->host_lock, flags);
95 	wd33c93_intr(host);
96 	spin_unlock_irqrestore(host->host_lock, flags);
97 
98 	return IRQ_HANDLED;
99 }
100 
101 static inline
102 void fill_hpc_entries(struct hpc_chunk *hcp, Scsi_Cmnd *cmd, int datainp)
103 {
104 	unsigned long len = cmd->SCp.this_residual;
105 	void *addr = cmd->SCp.ptr;
106 	dma_addr_t physaddr;
107 	unsigned long count;
108 
109 	physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
110 	cmd->SCp.dma_handle = physaddr;
111 
112 	while (len) {
113 		/*
114 		 * even cntinfo could be up to 16383, without
115 		 * magic only 8192 works correctly
116 		 */
117 		count = len > 8192 ? 8192 : len;
118 		hcp->desc.pbuf = physaddr;
119 		hcp->desc.cntinfo = count;
120 		hcp++;
121 		len -= count;
122 		physaddr += count;
123 	}
124 
125 	/*
126 	 * To make sure, if we trip an HPC bug, that we transfer every single
127 	 * byte, we tag on an extra zero length dma descriptor at the end of
128 	 * the chain.
129 	 */
130 	hcp->desc.pbuf = 0;
131 	hcp->desc.cntinfo = HPCDMA_EOX;
132 }
133 
134 static int dma_setup(Scsi_Cmnd *cmd, int datainp)
135 {
136 	struct ip22_hostdata *hdata = HDATA(cmd->device->host);
137 	struct hpc3_scsiregs *hregs =
138 		(struct hpc3_scsiregs *) cmd->device->host->base;
139 	struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
140 
141 	DPRINTK("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
142 
143 	hdata->wh.dma_dir = datainp;
144 
145 	/*
146 	 * wd33c93 shouldn't pass us bogus dma_setups, but it does:-(  The
147 	 * other wd33c93 drivers deal with it the same way (which isn't that
148 	 * obvious).  IMHO a better fix would be, not to do these dma setups
149 	 * in the first place.
150 	 */
151 	if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
152 		return 1;
153 
154 	fill_hpc_entries(hcp, cmd, datainp);
155 
156 	DPRINTK(" HPCGO\n");
157 
158 	/* Start up the HPC. */
159 	hregs->ndptr = hdata->hd.dma;
160 	if (datainp)
161 		hregs->ctrl = HPC3_SCTRL_ACTIVE;
162 	else
163 		hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
164 
165 	return 0;
166 }
167 
168 static void dma_stop(struct Scsi_Host *instance, Scsi_Cmnd *SCpnt,
169 		     int status)
170 {
171 	struct ip22_hostdata *hdata = HDATA(instance);
172 	struct hpc3_scsiregs *hregs;
173 
174 	if (!SCpnt)
175 		return;
176 
177 	hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
178 
179 	DPRINTK("dma_stop: status<%d> ", status);
180 
181 	/* First stop the HPC and flush it's FIFO. */
182 	if (hdata->wh.dma_dir) {
183 		hregs->ctrl |= HPC3_SCTRL_FLUSH;
184 		while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
185 			barrier();
186 	}
187 	hregs->ctrl = 0;
188 	dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
189 	                 SCpnt->sc_data_direction);
190 
191 	DPRINTK("\n");
192 }
193 
194 void sgiwd93_reset(unsigned long base)
195 {
196 	struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
197 
198 	hregs->ctrl = HPC3_SCTRL_CRESET;
199 	udelay(50);
200 	hregs->ctrl = 0;
201 }
202 
203 static inline void init_hpc_chain(struct hpc_data *hd)
204 {
205 	struct hpc_chunk *hcp = (struct hpc_chunk *) hd->cpu;
206 	struct hpc_chunk *dma = (struct hpc_chunk *) hd->dma;
207 	unsigned long start, end;
208 
209 	start = (unsigned long) hcp;
210 	end = start + PAGE_SIZE;
211 	while (start < end) {
212 		hcp->desc.pnext = (u32) (dma + 1);
213 		hcp->desc.cntinfo = HPCDMA_EOX;
214 		hcp++; dma++;
215 		start += sizeof(struct hpc_chunk);
216 	};
217 	hcp--;
218 	hcp->desc.pnext = hd->dma;
219 }
220 
221 static struct Scsi_Host * __init sgiwd93_setup_scsi(
222 	Scsi_Host_Template *SGIblows, int unit, int irq,
223 	struct hpc3_scsiregs *hregs, unsigned char *wdregs)
224 {
225 	struct ip22_hostdata *hdata;
226 	struct Scsi_Host *host;
227 	wd33c93_regs regs;
228 
229 	host = scsi_register(SGIblows, sizeof(struct ip22_hostdata));
230 	if (!host)
231 		return NULL;
232 
233 	host->base = (unsigned long) hregs;
234 	host->irq = irq;
235 
236 	hdata = HDATA(host);
237 	hdata->hd.cpu = dma_alloc_coherent(NULL, PAGE_SIZE, &hdata->hd.dma,
238 	                                   GFP_KERNEL);
239 	if (!hdata->hd.cpu) {
240 		printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
241 		       "host %d buffer.\n", unit);
242 		goto out_unregister;
243 	}
244 	init_hpc_chain(&hdata->hd);
245 
246 	regs.SASR = wdregs + 3;
247 	regs.SCMD = wdregs + 7;
248 
249 	wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_16_20);
250 
251 	hdata->wh.no_sync = 0;
252 
253 	if (request_irq(irq, sgiwd93_intr, 0, "SGI WD93", (void *) host)) {
254 		printk(KERN_WARNING "sgiwd93: Could not register irq %d "
255 		       "for host %d.\n", irq, unit);
256 		goto out_free;
257 	}
258 	return host;
259 
260 out_free:
261 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
262 	wd33c93_release();
263 
264 out_unregister:
265 	scsi_unregister(host);
266 
267 	return NULL;
268 }
269 
270 int __init sgiwd93_detect(Scsi_Host_Template *SGIblows)
271 {
272 	int found = 0;
273 
274 	SGIblows->proc_name = "SGIWD93";
275 	sgiwd93_host = sgiwd93_setup_scsi(SGIblows, 0, SGI_WD93_0_IRQ,
276 	                                  &hpc3c0->scsi_chan0,
277 	                                  (unsigned char *)hpc3c0->scsi0_ext);
278 	if (sgiwd93_host)
279 		found++;
280 
281 	/* Set up second controller on the Indigo2 */
282 	if (ip22_is_fullhouse()) {
283 		sgiwd93_host1 = sgiwd93_setup_scsi(SGIblows, 1, SGI_WD93_1_IRQ,
284 		                          &hpc3c0->scsi_chan1,
285 		                          (unsigned char *)hpc3c0->scsi1_ext);
286 		if (sgiwd93_host1)
287 			found++;
288 	}
289 
290 	return found;
291 }
292 
293 int sgiwd93_release(struct Scsi_Host *instance)
294 {
295 	struct ip22_hostdata *hdata = HDATA(instance);
296 	int irq = 0;
297 
298 	if (sgiwd93_host && sgiwd93_host == instance)
299 		irq = SGI_WD93_0_IRQ;
300 	else if (sgiwd93_host1 && sgiwd93_host1 == instance)
301 		irq = SGI_WD93_1_IRQ;
302 
303 	free_irq(irq, sgiwd93_intr);
304 	dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
305 	wd33c93_release();
306 
307 	return 1;
308 }
309 
310 static int sgiwd93_bus_reset(Scsi_Cmnd *cmd)
311 {
312 	/* FIXME perform bus-specific reset */
313 	wd33c93_host_reset(cmd);
314 	return SUCCESS;
315 }
316 
317 /*
318  * Kludge alert - the SCSI code calls the abort and reset method with int
319  * arguments not with pointers.  So this is going to blow up beautyfully
320  * on 64-bit systems with memory outside the compat address spaces.
321  */
322 static Scsi_Host_Template driver_template = {
323 	.proc_name		= "SGIWD93",
324 	.name			= "SGI WD93",
325 	.detect			= sgiwd93_detect,
326 	.release		= sgiwd93_release,
327 	.queuecommand		= wd33c93_queuecommand,
328 	.eh_abort_handler	= wd33c93_abort,
329 	.eh_bus_reset_handler	= sgiwd93_bus_reset,
330 	.eh_host_reset_handler	= wd33c93_host_reset,
331 	.can_queue		= CAN_QUEUE,
332 	.this_id		= 7,
333 	.sg_tablesize		= SG_ALL,
334 	.cmd_per_lun		= CMD_PER_LUN,
335 	.use_clustering		= DISABLE_CLUSTERING,
336 };
337 #include "scsi_module.c"
338