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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 ([email protected])
7 * Copyright (C) 1999 Andrew R. Baker ([email protected])
8 * Copyright (C) 2001 Florian Lohoff ([email protected])
9 * Copyright (C) 2003, 07 Ralf Baechle ([email protected])
10 *
11 * (In all truth, Jed Schimmel wrote all this code.)
12 */
13
14#undef DEBUG
15
16#include <linux/delay.h>
17#include <linux/dma-mapping.h>
18#include <linux/gfp.h>
19#include <linux/interrupt.h>
20#include <linux/init.h>
21#include <linux/kernel.h>
22#include <linux/types.h>
23#include <linux/module.h>
24#include <linux/platform_device.h>
25#include <linux/spinlock.h>
26
27#include <asm/sgi/hpc3.h>
28#include <asm/sgi/ip22.h>
29#include <asm/sgi/wd.h>
30
31#include <scsi/scsi.h>
32#include <scsi/scsi_cmnd.h>
33#include <scsi/scsi_device.h>
34#include <scsi/scsi_eh.h>
35#include <scsi/scsi_tcq.h>
36#include "wd33c93.h"
37
38struct ip22_hostdata {
39 struct WD33C93_hostdata wh;
40 dma_addr_t dma;
41 void *cpu;
42 struct device *dev;
43};
44
45#define host_to_hostdata(host) ((struct ip22_hostdata *)((host)->hostdata))
46
47struct hpc_chunk {
48 struct hpc_dma_desc desc;
49 u32 _padding; /* align to quadword boundary */
50};
51
52/* space for hpc dma descriptors */
53#define HPC_DMA_SIZE PAGE_SIZE
54
55#define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
56
57static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
58{
59 struct Scsi_Host * host = dev_id;
60 unsigned long flags;
61
62 spin_lock_irqsave(host->host_lock, flags);
63 wd33c93_intr(host);
64 spin_unlock_irqrestore(host->host_lock, flags);
65
66 return IRQ_HANDLED;
67}
68
69static inline
70void fill_hpc_entries(struct ip22_hostdata *hd, struct scsi_cmnd *cmd, int din)
71{
72 struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
73 unsigned long len = scsi_pointer->this_residual;
74 void *addr = scsi_pointer->ptr;
75 dma_addr_t physaddr;
76 unsigned long count;
77 struct hpc_chunk *hcp;
78
79 physaddr = dma_map_single(hd->dev, addr, len, DMA_DIR(din));
80 scsi_pointer->dma_handle = physaddr;
81 hcp = hd->cpu;
82
83 while (len) {
84 /*
85 * even cntinfo could be up to 16383, without
86 * magic only 8192 works correctly
87 */
88 count = len > 8192 ? 8192 : len;
89 hcp->desc.pbuf = physaddr;
90 hcp->desc.cntinfo = count;
91 hcp++;
92 len -= count;
93 physaddr += count;
94 }
95
96 /*
97 * To make sure, if we trip an HPC bug, that we transfer every single
98 * byte, we tag on an extra zero length dma descriptor at the end of
99 * the chain.
100 */
101 hcp->desc.pbuf = 0;
102 hcp->desc.cntinfo = HPCDMA_EOX;
103 dma_sync_single_for_device(hd->dev, hd->dma,
104 (unsigned long)(hcp + 1) - (unsigned long)hd->cpu,
105 DMA_TO_DEVICE);
106}
107
108static int dma_setup(struct scsi_cmnd *cmd, int datainp)
109{
110 struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
111 struct ip22_hostdata *hdata = host_to_hostdata(cmd->device->host);
112 struct hpc3_scsiregs *hregs =
113 (struct hpc3_scsiregs *) cmd->device->host->base;
114
115 pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hdata->cpu);
116
117 hdata->wh.dma_dir = datainp;
118
119 /*
120 * wd33c93 shouldn't pass us bogus dma_setups, but it does:-( The
121 * other wd33c93 drivers deal with it the same way (which isn't that
122 * obvious). IMHO a better fix would be, not to do these dma setups
123 * in the first place.
124 */
125 if (scsi_pointer->ptr == NULL || scsi_pointer->this_residual == 0)
126 return 1;
127
128 fill_hpc_entries(hdata, cmd, datainp);
129
130 pr_debug(" HPCGO\n");
131
132 /* Start up the HPC. */
133 hregs->ndptr = hdata->dma;
134 if (datainp)
135 hregs->ctrl = HPC3_SCTRL_ACTIVE;
136 else
137 hregs->ctrl = HPC3_SCTRL_ACTIVE | HPC3_SCTRL_DIR;
138
139 return 0;
140}
141
142static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
143 int status)
144{
145 struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(SCpnt);
146 struct ip22_hostdata *hdata = host_to_hostdata(instance);
147 struct hpc3_scsiregs *hregs;
148
149 if (!SCpnt)
150 return;
151
152 if (scsi_pointer->ptr == NULL || scsi_pointer->this_residual == 0)
153 return;
154
155 hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
156
157 pr_debug("dma_stop: status<%d> ", status);
158
159 /* First stop the HPC and flush it's FIFO. */
160 if (hdata->wh.dma_dir) {
161 hregs->ctrl |= HPC3_SCTRL_FLUSH;
162 while (hregs->ctrl & HPC3_SCTRL_ACTIVE)
163 barrier();
164 }
165 hregs->ctrl = 0;
166 dma_unmap_single(hdata->dev, scsi_pointer->dma_handle,
167 scsi_pointer->this_residual,
168 DMA_DIR(hdata->wh.dma_dir));
169
170 pr_debug("\n");
171}
172
173void sgiwd93_reset(unsigned long base)
174{
175 struct hpc3_scsiregs *hregs = (struct hpc3_scsiregs *) base;
176
177 hregs->ctrl = HPC3_SCTRL_CRESET;
178 udelay(50);
179 hregs->ctrl = 0;
180}
181EXPORT_SYMBOL_GPL(sgiwd93_reset);
182
183static inline void init_hpc_chain(struct ip22_hostdata *hdata)
184{
185 struct hpc_chunk *hcp = (struct hpc_chunk *)hdata->cpu;
186 dma_addr_t dma = hdata->dma;
187 unsigned long start, end;
188
189 start = (unsigned long) hcp;
190 end = start + HPC_DMA_SIZE;
191 while (start < end) {
192 hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk));
193 hcp->desc.cntinfo = HPCDMA_EOX;
194 hcp++;
195 dma += sizeof(struct hpc_chunk);
196 start += sizeof(struct hpc_chunk);
197 }
198 hcp--;
199 hcp->desc.pnext = hdata->dma;
200}
201
202/*
203 * Kludge alert - the SCSI code calls the abort and reset method with int
204 * arguments not with pointers. So this is going to blow up beautyfully
205 * on 64-bit systems with memory outside the compat address spaces.
206 */
207static const struct scsi_host_template sgiwd93_template = {
208 .module = THIS_MODULE,
209 .proc_name = "SGIWD93",
210 .name = "SGI WD93",
211 .queuecommand = wd33c93_queuecommand,
212 .eh_abort_handler = wd33c93_abort,
213 .eh_host_reset_handler = wd33c93_host_reset,
214 .can_queue = 16,
215 .this_id = 7,
216 .sg_tablesize = SG_ALL,
217 .cmd_per_lun = 8,
218 .dma_boundary = PAGE_SIZE - 1,
219 .cmd_size = sizeof(struct scsi_pointer),
220};
221
222static int sgiwd93_probe(struct platform_device *pdev)
223{
224 struct sgiwd93_platform_data *pd = pdev->dev.platform_data;
225 unsigned char *wdregs = pd->wdregs;
226 struct hpc3_scsiregs *hregs = pd->hregs;
227 struct ip22_hostdata *hdata;
228 struct Scsi_Host *host;
229 wd33c93_regs regs;
230 unsigned int unit = pd->unit;
231 unsigned int irq = pd->irq;
232 int err;
233
234 host = scsi_host_alloc(&sgiwd93_template, sizeof(struct ip22_hostdata));
235 if (!host) {
236 err = -ENOMEM;
237 goto out;
238 }
239
240 host->base = (unsigned long) hregs;
241 host->irq = irq;
242
243 hdata = host_to_hostdata(host);
244 hdata->dev = &pdev->dev;
245 hdata->cpu = dma_alloc_noncoherent(&pdev->dev, HPC_DMA_SIZE,
246 &hdata->dma, DMA_TO_DEVICE, GFP_KERNEL);
247 if (!hdata->cpu) {
248 printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
249 "host %d buffer.\n", unit);
250 err = -ENOMEM;
251 goto out_put;
252 }
253
254 init_hpc_chain(hdata);
255
256 regs.SASR = wdregs + 3;
257 regs.SCMD = wdregs + 7;
258
259 hdata->wh.no_sync = 0;
260 hdata->wh.fast = 1;
261 hdata->wh.dma_mode = CTRL_BURST;
262
263 wd33c93_init(host, regs, dma_setup, dma_stop, WD33C93_FS_MHZ(20));
264
265 err = request_irq(irq, sgiwd93_intr, 0, "SGI WD93", host);
266 if (err) {
267 printk(KERN_WARNING "sgiwd93: Could not register irq %d "
268 "for host %d.\n", irq, unit);
269 goto out_free;
270 }
271
272 platform_set_drvdata(pdev, host);
273
274 err = scsi_add_host(host, NULL);
275 if (err)
276 goto out_irq;
277
278 scsi_scan_host(host);
279
280 return 0;
281
282out_irq:
283 free_irq(irq, host);
284out_free:
285 dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
286 DMA_TO_DEVICE);
287out_put:
288 scsi_host_put(host);
289out:
290
291 return err;
292}
293
294static void sgiwd93_remove(struct platform_device *pdev)
295{
296 struct Scsi_Host *host = platform_get_drvdata(pdev);
297 struct ip22_hostdata *hdata = (struct ip22_hostdata *) host->hostdata;
298 struct sgiwd93_platform_data *pd = pdev->dev.platform_data;
299
300 scsi_remove_host(host);
301 free_irq(pd->irq, host);
302 dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma,
303 DMA_TO_DEVICE);
304 scsi_host_put(host);
305}
306
307static struct platform_driver sgiwd93_driver = {
308 .probe = sgiwd93_probe,
309 .remove = sgiwd93_remove,
310 .driver = {
311 .name = "sgiwd93",
312 }
313};
314
315static int __init sgiwd93_module_init(void)
316{
317 return platform_driver_register(&sgiwd93_driver);
318}
319
320static void __exit sgiwd93_module_exit(void)
321{
322 return platform_driver_unregister(&sgiwd93_driver);
323}
324
325module_init(sgiwd93_module_init);
326module_exit(sgiwd93_module_exit);
327
328MODULE_DESCRIPTION("SGI WD33C93 driver");
329MODULE_AUTHOR("Ralf Baechle <[email protected]>");
330MODULE_LICENSE("GPL");
331MODULE_ALIAS("platform:sgiwd93");