1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* mac_esp.c: ESP front-end for Macintosh Quadra systems. |
3 | * |
4 | * Adapted from jazz_esp.c and the old mac_esp.c. |
5 | * |
6 | * The pseudo DMA algorithm is based on the one used in NetBSD. |
7 | * See sys/arch/mac68k/obio/esp.c for some background information. |
8 | * |
9 | * Copyright (C) 2007-2008 Finn Thain |
10 | */ |
11 | |
12 | #include <linux/kernel.h> |
13 | #include <linux/types.h> |
14 | #include <linux/module.h> |
15 | #include <linux/init.h> |
16 | #include <linux/interrupt.h> |
17 | #include <linux/platform_device.h> |
18 | #include <linux/dma-mapping.h> |
19 | #include <linux/scatterlist.h> |
20 | #include <linux/delay.h> |
21 | #include <linux/io.h> |
22 | #include <linux/nubus.h> |
23 | #include <linux/slab.h> |
24 | |
25 | #include <asm/irq.h> |
26 | #include <asm/dma.h> |
27 | #include <asm/macints.h> |
28 | #include <asm/macintosh.h> |
29 | #include <asm/mac_via.h> |
30 | |
31 | #include <scsi/scsi_host.h> |
32 | |
33 | #include "esp_scsi.h" |
34 | |
35 | #define DRV_MODULE_NAME "mac_esp" |
36 | #define PFX DRV_MODULE_NAME ": " |
37 | #define DRV_VERSION "1.000" |
38 | #define DRV_MODULE_RELDATE "Sept 15, 2007" |
39 | |
40 | #define MAC_ESP_IO_BASE 0x50F00000 |
41 | #define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000) |
42 | #define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000) |
43 | #define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000) |
44 | #define MAC_ESP_REGS_SPACING 0x402 |
45 | #define MAC_ESP_PDMA_REG 0xF9800024 |
46 | #define MAC_ESP_PDMA_REG_SPACING 0x4 |
47 | #define MAC_ESP_PDMA_IO_OFFSET 0x100 |
48 | |
49 | #define esp_read8(REG) mac_esp_read8(esp, REG) |
50 | #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG) |
51 | |
52 | struct mac_esp_priv { |
53 | struct esp *esp; |
54 | void __iomem *pdma_regs; |
55 | void __iomem *pdma_io; |
56 | }; |
57 | static struct esp *esp_chips[2]; |
58 | static DEFINE_SPINLOCK(esp_chips_lock); |
59 | |
60 | #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \ |
61 | dev_get_drvdata((esp)->dev)) |
62 | |
63 | static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg) |
64 | { |
65 | nubus_writeb(val, esp->regs + reg * 16); |
66 | } |
67 | |
68 | static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg) |
69 | { |
70 | return nubus_readb(esp->regs + reg * 16); |
71 | } |
72 | |
73 | static void mac_esp_reset_dma(struct esp *esp) |
74 | { |
75 | /* Nothing to do. */ |
76 | } |
77 | |
78 | static void mac_esp_dma_drain(struct esp *esp) |
79 | { |
80 | /* Nothing to do. */ |
81 | } |
82 | |
83 | static void mac_esp_dma_invalidate(struct esp *esp) |
84 | { |
85 | /* Nothing to do. */ |
86 | } |
87 | |
88 | static int mac_esp_dma_error(struct esp *esp) |
89 | { |
90 | return esp->send_cmd_error; |
91 | } |
92 | |
93 | static inline int mac_esp_wait_for_empty_fifo(struct esp *esp) |
94 | { |
95 | int i = 500000; |
96 | |
97 | do { |
98 | if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES)) |
99 | return 0; |
100 | |
101 | if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) |
102 | return 1; |
103 | |
104 | udelay(2); |
105 | } while (--i); |
106 | |
107 | printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n" , |
108 | esp_read8(ESP_STATUS)); |
109 | esp->send_cmd_error = 1; |
110 | return 1; |
111 | } |
112 | |
113 | static inline int mac_esp_wait_for_dreq(struct esp *esp) |
114 | { |
115 | struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); |
116 | int i = 500000; |
117 | |
118 | do { |
119 | if (mep->pdma_regs == NULL) { |
120 | if (via2_scsi_drq_pending()) |
121 | return 0; |
122 | } else { |
123 | if (nubus_readl(mep->pdma_regs) & 0x200) |
124 | return 0; |
125 | } |
126 | |
127 | if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) |
128 | return 1; |
129 | |
130 | udelay(2); |
131 | } while (--i); |
132 | |
133 | printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n" , |
134 | esp_read8(ESP_STATUS)); |
135 | esp->send_cmd_error = 1; |
136 | return 1; |
137 | } |
138 | |
139 | #define MAC_ESP_PDMA_LOOP(operands) \ |
140 | asm volatile ( \ |
141 | " tstw %1 \n" \ |
142 | " jbeq 20f \n" \ |
143 | "1: movew " operands " \n" \ |
144 | "2: movew " operands " \n" \ |
145 | "3: movew " operands " \n" \ |
146 | "4: movew " operands " \n" \ |
147 | "5: movew " operands " \n" \ |
148 | "6: movew " operands " \n" \ |
149 | "7: movew " operands " \n" \ |
150 | "8: movew " operands " \n" \ |
151 | "9: movew " operands " \n" \ |
152 | "10: movew " operands " \n" \ |
153 | "11: movew " operands " \n" \ |
154 | "12: movew " operands " \n" \ |
155 | "13: movew " operands " \n" \ |
156 | "14: movew " operands " \n" \ |
157 | "15: movew " operands " \n" \ |
158 | "16: movew " operands " \n" \ |
159 | " subqw #1,%1 \n" \ |
160 | " jbne 1b \n" \ |
161 | "20: tstw %2 \n" \ |
162 | " jbeq 30f \n" \ |
163 | "21: movew " operands " \n" \ |
164 | " subqw #1,%2 \n" \ |
165 | " jbne 21b \n" \ |
166 | "30: tstw %3 \n" \ |
167 | " jbeq 40f \n" \ |
168 | "31: moveb " operands " \n" \ |
169 | "32: nop \n" \ |
170 | "40: \n" \ |
171 | " \n" \ |
172 | " .section __ex_table,\"a\" \n" \ |
173 | " .align 4 \n" \ |
174 | " .long 1b,40b \n" \ |
175 | " .long 2b,40b \n" \ |
176 | " .long 3b,40b \n" \ |
177 | " .long 4b,40b \n" \ |
178 | " .long 5b,40b \n" \ |
179 | " .long 6b,40b \n" \ |
180 | " .long 7b,40b \n" \ |
181 | " .long 8b,40b \n" \ |
182 | " .long 9b,40b \n" \ |
183 | " .long 10b,40b \n" \ |
184 | " .long 11b,40b \n" \ |
185 | " .long 12b,40b \n" \ |
186 | " .long 13b,40b \n" \ |
187 | " .long 14b,40b \n" \ |
188 | " .long 15b,40b \n" \ |
189 | " .long 16b,40b \n" \ |
190 | " .long 21b,40b \n" \ |
191 | " .long 31b,40b \n" \ |
192 | " .long 32b,40b \n" \ |
193 | " .previous \n" \ |
194 | : "+a" (addr), "+r" (count32), "+r" (count2) \ |
195 | : "g" (count1), "a" (mep->pdma_io)) |
196 | |
197 | static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count, |
198 | u32 dma_count, int write, u8 cmd) |
199 | { |
200 | struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp); |
201 | |
202 | esp->send_cmd_error = 0; |
203 | |
204 | if (!write) |
205 | scsi_esp_cmd(esp, ESP_CMD_FLUSH); |
206 | |
207 | esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW); |
208 | esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED); |
209 | |
210 | scsi_esp_cmd(esp, cmd); |
211 | |
212 | do { |
213 | unsigned int count32 = esp_count >> 5; |
214 | unsigned int count2 = (esp_count & 0x1F) >> 1; |
215 | unsigned int count1 = esp_count & 1; |
216 | unsigned int start_addr = addr; |
217 | |
218 | if (mac_esp_wait_for_dreq(esp)) |
219 | break; |
220 | |
221 | if (write) { |
222 | MAC_ESP_PDMA_LOOP("%4@,%0@+" ); |
223 | |
224 | esp_count -= addr - start_addr; |
225 | } else { |
226 | unsigned int n; |
227 | |
228 | MAC_ESP_PDMA_LOOP("%0@+,%4@" ); |
229 | |
230 | if (mac_esp_wait_for_empty_fifo(esp)) |
231 | break; |
232 | |
233 | n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW); |
234 | addr = start_addr + esp_count - n; |
235 | esp_count = n; |
236 | } |
237 | } while (esp_count); |
238 | } |
239 | |
240 | static int mac_esp_irq_pending(struct esp *esp) |
241 | { |
242 | if (esp_read8(ESP_STATUS) & ESP_STAT_INTR) |
243 | return 1; |
244 | return 0; |
245 | } |
246 | |
247 | static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len) |
248 | { |
249 | return dma_len > 0xFFFF ? 0xFFFF : dma_len; |
250 | } |
251 | |
252 | static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id) |
253 | { |
254 | int got_intr; |
255 | |
256 | /* |
257 | * This is an edge triggered IRQ, so we have to be careful to |
258 | * avoid missing a transition when it is shared by two ESP devices. |
259 | */ |
260 | |
261 | do { |
262 | got_intr = 0; |
263 | if (esp_chips[0] && |
264 | (mac_esp_read8(esp: esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) { |
265 | (void)scsi_esp_intr(irq, esp_chips[0]); |
266 | got_intr = 1; |
267 | } |
268 | if (esp_chips[1] && |
269 | (mac_esp_read8(esp: esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) { |
270 | (void)scsi_esp_intr(irq, esp_chips[1]); |
271 | got_intr = 1; |
272 | } |
273 | } while (got_intr); |
274 | |
275 | return IRQ_HANDLED; |
276 | } |
277 | |
278 | static struct esp_driver_ops mac_esp_ops = { |
279 | .esp_write8 = mac_esp_write8, |
280 | .esp_read8 = mac_esp_read8, |
281 | .irq_pending = mac_esp_irq_pending, |
282 | .dma_length_limit = mac_esp_dma_length_limit, |
283 | .reset_dma = mac_esp_reset_dma, |
284 | .dma_drain = mac_esp_dma_drain, |
285 | .dma_invalidate = mac_esp_dma_invalidate, |
286 | .send_dma_cmd = mac_esp_send_pdma_cmd, |
287 | .dma_error = mac_esp_dma_error, |
288 | }; |
289 | |
290 | static int esp_mac_probe(struct platform_device *dev) |
291 | { |
292 | const struct scsi_host_template *tpnt = &scsi_esp_template; |
293 | struct Scsi_Host *host; |
294 | struct esp *esp; |
295 | int err; |
296 | struct mac_esp_priv *mep; |
297 | |
298 | if (!MACH_IS_MAC) |
299 | return -ENODEV; |
300 | |
301 | if (dev->id > 1) |
302 | return -ENODEV; |
303 | |
304 | host = scsi_host_alloc(tpnt, sizeof(struct esp)); |
305 | |
306 | err = -ENOMEM; |
307 | if (!host) |
308 | goto fail; |
309 | |
310 | host->max_id = 8; |
311 | host->dma_boundary = PAGE_SIZE - 1; |
312 | esp = shost_priv(shost: host); |
313 | |
314 | esp->host = host; |
315 | esp->dev = &dev->dev; |
316 | |
317 | esp->command_block = kzalloc(size: 16, GFP_KERNEL); |
318 | if (!esp->command_block) |
319 | goto fail_unlink; |
320 | esp->command_block_dma = (dma_addr_t)esp->command_block; |
321 | |
322 | esp->scsi_id = 7; |
323 | host->this_id = esp->scsi_id; |
324 | esp->scsi_id_mask = 1 << esp->scsi_id; |
325 | |
326 | mep = kzalloc(size: sizeof(struct mac_esp_priv), GFP_KERNEL); |
327 | if (!mep) |
328 | goto fail_free_command_block; |
329 | mep->esp = esp; |
330 | platform_set_drvdata(pdev: dev, data: mep); |
331 | |
332 | switch (macintosh_config->scsi_type) { |
333 | case MAC_SCSI_QUADRA: |
334 | esp->cfreq = 16500000; |
335 | esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA; |
336 | mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; |
337 | mep->pdma_regs = NULL; |
338 | break; |
339 | case MAC_SCSI_QUADRA2: |
340 | esp->cfreq = 25000000; |
341 | esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 + |
342 | dev->id * MAC_ESP_REGS_SPACING); |
343 | mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET; |
344 | mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG + |
345 | dev->id * MAC_ESP_PDMA_REG_SPACING); |
346 | nubus_writel(0x1d1, mep->pdma_regs); |
347 | break; |
348 | case MAC_SCSI_QUADRA3: |
349 | /* These quadras have a real DMA controller (the PSC) but we |
350 | * don't know how to drive it so we must use PIO instead. |
351 | */ |
352 | esp->cfreq = 25000000; |
353 | esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3; |
354 | mep->pdma_io = NULL; |
355 | mep->pdma_regs = NULL; |
356 | break; |
357 | } |
358 | esp->fifo_reg = esp->regs + ESP_FDATA * 16; |
359 | |
360 | esp->ops = &mac_esp_ops; |
361 | esp->flags = ESP_FLAG_NO_DMA_MAP; |
362 | if (mep->pdma_io == NULL) { |
363 | printk(KERN_INFO PFX "using PIO for controller %d\n" , dev->id); |
364 | esp_write8(0, ESP_TCLOW); |
365 | esp_write8(0, ESP_TCMED); |
366 | esp->flags |= ESP_FLAG_DISABLE_SYNC; |
367 | mac_esp_ops.send_dma_cmd = esp_send_pio_cmd; |
368 | } else { |
369 | printk(KERN_INFO PFX "using PDMA for controller %d\n" , dev->id); |
370 | } |
371 | |
372 | host->irq = IRQ_MAC_SCSI; |
373 | |
374 | /* The request_irq() call is intended to succeed for the first device |
375 | * and fail for the second device. |
376 | */ |
377 | err = request_irq(irq: host->irq, handler: mac_scsi_esp_intr, flags: 0, name: "ESP" , NULL); |
378 | spin_lock(lock: &esp_chips_lock); |
379 | if (err < 0 && esp_chips[!dev->id] == NULL) { |
380 | spin_unlock(lock: &esp_chips_lock); |
381 | goto fail_free_priv; |
382 | } |
383 | esp_chips[dev->id] = esp; |
384 | spin_unlock(lock: &esp_chips_lock); |
385 | |
386 | err = scsi_esp_register(esp); |
387 | if (err) |
388 | goto fail_free_irq; |
389 | |
390 | return 0; |
391 | |
392 | fail_free_irq: |
393 | spin_lock(lock: &esp_chips_lock); |
394 | esp_chips[dev->id] = NULL; |
395 | if (esp_chips[!dev->id] == NULL) { |
396 | spin_unlock(lock: &esp_chips_lock); |
397 | free_irq(host->irq, NULL); |
398 | } else |
399 | spin_unlock(lock: &esp_chips_lock); |
400 | fail_free_priv: |
401 | kfree(objp: mep); |
402 | fail_free_command_block: |
403 | kfree(objp: esp->command_block); |
404 | fail_unlink: |
405 | scsi_host_put(t: host); |
406 | fail: |
407 | return err; |
408 | } |
409 | |
410 | static void esp_mac_remove(struct platform_device *dev) |
411 | { |
412 | struct mac_esp_priv *mep = platform_get_drvdata(pdev: dev); |
413 | struct esp *esp = mep->esp; |
414 | unsigned int irq = esp->host->irq; |
415 | |
416 | scsi_esp_unregister(esp); |
417 | |
418 | spin_lock(lock: &esp_chips_lock); |
419 | esp_chips[dev->id] = NULL; |
420 | if (esp_chips[!dev->id] == NULL) { |
421 | spin_unlock(lock: &esp_chips_lock); |
422 | free_irq(irq, NULL); |
423 | } else |
424 | spin_unlock(lock: &esp_chips_lock); |
425 | |
426 | kfree(objp: mep); |
427 | |
428 | kfree(objp: esp->command_block); |
429 | |
430 | scsi_host_put(t: esp->host); |
431 | } |
432 | |
433 | static struct platform_driver esp_mac_driver = { |
434 | .probe = esp_mac_probe, |
435 | .remove_new = esp_mac_remove, |
436 | .driver = { |
437 | .name = DRV_MODULE_NAME, |
438 | }, |
439 | }; |
440 | module_platform_driver(esp_mac_driver); |
441 | |
442 | MODULE_DESCRIPTION("Mac ESP SCSI driver" ); |
443 | MODULE_AUTHOR("Finn Thain" ); |
444 | MODULE_LICENSE("GPL v2" ); |
445 | MODULE_VERSION(DRV_VERSION); |
446 | MODULE_ALIAS("platform:" DRV_MODULE_NAME); |
447 | |