blk-mq: always free hctx after request queue is freed
[linux/fpc-iii.git] / drivers / scsi / mac_esp.c
blobee741207fd4e497d77aed39919866e3015072f5c
1 /* mac_esp.c: ESP front-end for Macintosh Quadra systems.
3 * Adapted from jazz_esp.c and the old mac_esp.c.
5 * The pseudo DMA algorithm is based on the one used in NetBSD.
6 * See sys/arch/mac68k/obio/esp.c for some background information.
8 * Copyright (C) 2007-2008 Finn Thain
9 */
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/platform_device.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/scatterlist.h>
19 #include <linux/delay.h>
20 #include <linux/io.h>
21 #include <linux/nubus.h>
22 #include <linux/slab.h>
24 #include <asm/irq.h>
25 #include <asm/dma.h>
26 #include <asm/macints.h>
27 #include <asm/macintosh.h>
28 #include <asm/mac_via.h>
30 #include <scsi/scsi_host.h>
32 #include "esp_scsi.h"
34 #define DRV_MODULE_NAME "mac_esp"
35 #define PFX DRV_MODULE_NAME ": "
36 #define DRV_VERSION "1.000"
37 #define DRV_MODULE_RELDATE "Sept 15, 2007"
39 #define MAC_ESP_IO_BASE 0x50F00000
40 #define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000)
41 #define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000)
42 #define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000)
43 #define MAC_ESP_REGS_SPACING 0x402
44 #define MAC_ESP_PDMA_REG 0xF9800024
45 #define MAC_ESP_PDMA_REG_SPACING 0x4
46 #define MAC_ESP_PDMA_IO_OFFSET 0x100
48 #define esp_read8(REG) mac_esp_read8(esp, REG)
49 #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG)
51 struct mac_esp_priv {
52 struct esp *esp;
53 void __iomem *pdma_regs;
54 void __iomem *pdma_io;
56 static struct esp *esp_chips[2];
57 static DEFINE_SPINLOCK(esp_chips_lock);
59 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
60 dev_get_drvdata((esp)->dev))
62 static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
64 nubus_writeb(val, esp->regs + reg * 16);
67 static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
69 return nubus_readb(esp->regs + reg * 16);
72 static void mac_esp_reset_dma(struct esp *esp)
74 /* Nothing to do. */
77 static void mac_esp_dma_drain(struct esp *esp)
79 /* Nothing to do. */
82 static void mac_esp_dma_invalidate(struct esp *esp)
84 /* Nothing to do. */
87 static int mac_esp_dma_error(struct esp *esp)
89 return esp->send_cmd_error;
92 static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
94 int i = 500000;
96 do {
97 if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
98 return 0;
100 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
101 return 1;
103 udelay(2);
104 } while (--i);
106 printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
107 esp_read8(ESP_STATUS));
108 esp->send_cmd_error = 1;
109 return 1;
112 static inline int mac_esp_wait_for_dreq(struct esp *esp)
114 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
115 int i = 500000;
117 do {
118 if (mep->pdma_regs == NULL) {
119 if (via2_scsi_drq_pending())
120 return 0;
121 } else {
122 if (nubus_readl(mep->pdma_regs) & 0x200)
123 return 0;
126 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
127 return 1;
129 udelay(2);
130 } while (--i);
132 printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
133 esp_read8(ESP_STATUS));
134 esp->send_cmd_error = 1;
135 return 1;
138 #define MAC_ESP_PDMA_LOOP(operands) \
139 asm volatile ( \
140 " tstw %1 \n" \
141 " jbeq 20f \n" \
142 "1: movew " operands " \n" \
143 "2: movew " operands " \n" \
144 "3: movew " operands " \n" \
145 "4: movew " operands " \n" \
146 "5: movew " operands " \n" \
147 "6: movew " operands " \n" \
148 "7: movew " operands " \n" \
149 "8: movew " operands " \n" \
150 "9: movew " operands " \n" \
151 "10: movew " operands " \n" \
152 "11: movew " operands " \n" \
153 "12: movew " operands " \n" \
154 "13: movew " operands " \n" \
155 "14: movew " operands " \n" \
156 "15: movew " operands " \n" \
157 "16: movew " operands " \n" \
158 " subqw #1,%1 \n" \
159 " jbne 1b \n" \
160 "20: tstw %2 \n" \
161 " jbeq 30f \n" \
162 "21: movew " operands " \n" \
163 " subqw #1,%2 \n" \
164 " jbne 21b \n" \
165 "30: tstw %3 \n" \
166 " jbeq 40f \n" \
167 "31: moveb " operands " \n" \
168 "32: nop \n" \
169 "40: \n" \
170 " \n" \
171 " .section __ex_table,\"a\" \n" \
172 " .align 4 \n" \
173 " .long 1b,40b \n" \
174 " .long 2b,40b \n" \
175 " .long 3b,40b \n" \
176 " .long 4b,40b \n" \
177 " .long 5b,40b \n" \
178 " .long 6b,40b \n" \
179 " .long 7b,40b \n" \
180 " .long 8b,40b \n" \
181 " .long 9b,40b \n" \
182 " .long 10b,40b \n" \
183 " .long 11b,40b \n" \
184 " .long 12b,40b \n" \
185 " .long 13b,40b \n" \
186 " .long 14b,40b \n" \
187 " .long 15b,40b \n" \
188 " .long 16b,40b \n" \
189 " .long 21b,40b \n" \
190 " .long 31b,40b \n" \
191 " .long 32b,40b \n" \
192 " .previous \n" \
193 : "+a" (addr), "+r" (count32), "+r" (count2) \
194 : "g" (count1), "a" (mep->pdma_io))
196 static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
197 u32 dma_count, int write, u8 cmd)
199 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
201 esp->send_cmd_error = 0;
203 if (!write)
204 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
206 esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
207 esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
209 scsi_esp_cmd(esp, cmd);
211 do {
212 unsigned int count32 = esp_count >> 5;
213 unsigned int count2 = (esp_count & 0x1F) >> 1;
214 unsigned int count1 = esp_count & 1;
215 unsigned int start_addr = addr;
217 if (mac_esp_wait_for_dreq(esp))
218 break;
220 if (write) {
221 MAC_ESP_PDMA_LOOP("%4@,%0@+");
223 esp_count -= addr - start_addr;
224 } else {
225 unsigned int n;
227 MAC_ESP_PDMA_LOOP("%0@+,%4@");
229 if (mac_esp_wait_for_empty_fifo(esp))
230 break;
232 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
233 addr = start_addr + esp_count - n;
234 esp_count = n;
236 } while (esp_count);
239 static int mac_esp_irq_pending(struct esp *esp)
241 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
242 return 1;
243 return 0;
246 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
248 return dma_len > 0xFFFF ? 0xFFFF : dma_len;
251 static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
253 int got_intr;
256 * This is an edge triggered IRQ, so we have to be careful to
257 * avoid missing a transition when it is shared by two ESP devices.
260 do {
261 got_intr = 0;
262 if (esp_chips[0] &&
263 (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
264 (void)scsi_esp_intr(irq, esp_chips[0]);
265 got_intr = 1;
267 if (esp_chips[1] &&
268 (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
269 (void)scsi_esp_intr(irq, esp_chips[1]);
270 got_intr = 1;
272 } while (got_intr);
274 return IRQ_HANDLED;
277 static struct esp_driver_ops mac_esp_ops = {
278 .esp_write8 = mac_esp_write8,
279 .esp_read8 = mac_esp_read8,
280 .irq_pending = mac_esp_irq_pending,
281 .dma_length_limit = mac_esp_dma_length_limit,
282 .reset_dma = mac_esp_reset_dma,
283 .dma_drain = mac_esp_dma_drain,
284 .dma_invalidate = mac_esp_dma_invalidate,
285 .send_dma_cmd = mac_esp_send_pdma_cmd,
286 .dma_error = mac_esp_dma_error,
289 static int esp_mac_probe(struct platform_device *dev)
291 struct scsi_host_template *tpnt = &scsi_esp_template;
292 struct Scsi_Host *host;
293 struct esp *esp;
294 int err;
295 struct mac_esp_priv *mep;
297 if (!MACH_IS_MAC)
298 return -ENODEV;
300 if (dev->id > 1)
301 return -ENODEV;
303 host = scsi_host_alloc(tpnt, sizeof(struct esp));
305 err = -ENOMEM;
306 if (!host)
307 goto fail;
309 host->max_id = 8;
310 host->dma_boundary = PAGE_SIZE - 1;
311 esp = shost_priv(host);
313 esp->host = host;
314 esp->dev = &dev->dev;
316 esp->command_block = kzalloc(16, GFP_KERNEL);
317 if (!esp->command_block)
318 goto fail_unlink;
319 esp->command_block_dma = (dma_addr_t)esp->command_block;
321 esp->scsi_id = 7;
322 host->this_id = esp->scsi_id;
323 esp->scsi_id_mask = 1 << esp->scsi_id;
325 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
326 if (!mep)
327 goto fail_free_command_block;
328 mep->esp = esp;
329 platform_set_drvdata(dev, mep);
331 switch (macintosh_config->scsi_type) {
332 case MAC_SCSI_QUADRA:
333 esp->cfreq = 16500000;
334 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA;
335 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
336 mep->pdma_regs = NULL;
337 break;
338 case MAC_SCSI_QUADRA2:
339 esp->cfreq = 25000000;
340 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
341 dev->id * MAC_ESP_REGS_SPACING);
342 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
343 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
344 dev->id * MAC_ESP_PDMA_REG_SPACING);
345 nubus_writel(0x1d1, mep->pdma_regs);
346 break;
347 case MAC_SCSI_QUADRA3:
348 /* These quadras have a real DMA controller (the PSC) but we
349 * don't know how to drive it so we must use PIO instead.
351 esp->cfreq = 25000000;
352 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3;
353 mep->pdma_io = NULL;
354 mep->pdma_regs = NULL;
355 break;
357 esp->fifo_reg = esp->regs + ESP_FDATA * 16;
359 esp->ops = &mac_esp_ops;
360 esp->flags = ESP_FLAG_NO_DMA_MAP;
361 if (mep->pdma_io == NULL) {
362 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
363 esp_write8(0, ESP_TCLOW);
364 esp_write8(0, ESP_TCMED);
365 esp->flags |= ESP_FLAG_DISABLE_SYNC;
366 mac_esp_ops.send_dma_cmd = esp_send_pio_cmd;
367 } else {
368 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
371 host->irq = IRQ_MAC_SCSI;
373 /* The request_irq() call is intended to succeed for the first device
374 * and fail for the second device.
376 err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
377 spin_lock(&esp_chips_lock);
378 if (err < 0 && esp_chips[!dev->id] == NULL) {
379 spin_unlock(&esp_chips_lock);
380 goto fail_free_priv;
382 esp_chips[dev->id] = esp;
383 spin_unlock(&esp_chips_lock);
385 err = scsi_esp_register(esp);
386 if (err)
387 goto fail_free_irq;
389 return 0;
391 fail_free_irq:
392 spin_lock(&esp_chips_lock);
393 esp_chips[dev->id] = NULL;
394 if (esp_chips[!dev->id] == NULL) {
395 spin_unlock(&esp_chips_lock);
396 free_irq(host->irq, NULL);
397 } else
398 spin_unlock(&esp_chips_lock);
399 fail_free_priv:
400 kfree(mep);
401 fail_free_command_block:
402 kfree(esp->command_block);
403 fail_unlink:
404 scsi_host_put(host);
405 fail:
406 return err;
409 static int esp_mac_remove(struct platform_device *dev)
411 struct mac_esp_priv *mep = platform_get_drvdata(dev);
412 struct esp *esp = mep->esp;
413 unsigned int irq = esp->host->irq;
415 scsi_esp_unregister(esp);
417 spin_lock(&esp_chips_lock);
418 esp_chips[dev->id] = NULL;
419 if (esp_chips[!dev->id] == NULL) {
420 spin_unlock(&esp_chips_lock);
421 free_irq(irq, NULL);
422 } else
423 spin_unlock(&esp_chips_lock);
425 kfree(mep);
427 kfree(esp->command_block);
429 scsi_host_put(esp->host);
431 return 0;
434 static struct platform_driver esp_mac_driver = {
435 .probe = esp_mac_probe,
436 .remove = esp_mac_remove,
437 .driver = {
438 .name = DRV_MODULE_NAME,
442 static int __init mac_esp_init(void)
444 return platform_driver_register(&esp_mac_driver);
447 static void __exit mac_esp_exit(void)
449 platform_driver_unregister(&esp_mac_driver);
452 MODULE_DESCRIPTION("Mac ESP SCSI driver");
453 MODULE_AUTHOR("Finn Thain");
454 MODULE_LICENSE("GPL v2");
455 MODULE_VERSION(DRV_VERSION);
456 MODULE_ALIAS("platform:" DRV_MODULE_NAME);
458 module_init(mac_esp_init);
459 module_exit(mac_esp_exit);