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
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>
21 #include <linux/nubus.h>
25 #include <asm/macints.h>
26 #include <asm/macintosh.h>
28 #include <scsi/scsi_host.h>
32 #define DRV_MODULE_NAME "mac_esp"
33 #define PFX DRV_MODULE_NAME ": "
34 #define DRV_VERSION "1.000"
35 #define DRV_MODULE_RELDATE "Sept 15, 2007"
37 #define MAC_ESP_IO_BASE 0x50F00000
38 #define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000)
39 #define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000)
40 #define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000)
41 #define MAC_ESP_REGS_SPACING 0x402
42 #define MAC_ESP_PDMA_REG 0xF9800024
43 #define MAC_ESP_PDMA_REG_SPACING 0x4
44 #define MAC_ESP_PDMA_IO_OFFSET 0x100
46 #define esp_read8(REG) mac_esp_read8(esp, REG)
47 #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG)
51 void __iomem *pdma_regs;
52 void __iomem *pdma_io;
55 static struct esp *esp_chips[2];
57 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
58 platform_get_drvdata((struct platform_device *) \
61 static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
63 nubus_writeb(val, esp->regs + reg * 16);
66 static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
68 return nubus_readb(esp->regs + reg * 16);
71 /* For pseudo DMA and PIO we need the virtual address
72 * so this address mapping is the identity mapping.
75 static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf,
78 return (dma_addr_t)buf;
81 static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg,
86 for (i = 0; i < num_sg; i++)
87 sg[i].dma_address = (u32)sg_virt(&sg[i]);
91 static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
97 static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
103 static void mac_esp_reset_dma(struct esp *esp)
108 static void mac_esp_dma_drain(struct esp *esp)
113 static void mac_esp_dma_invalidate(struct esp *esp)
118 static int mac_esp_dma_error(struct esp *esp)
120 return MAC_ESP_GET_PRIV(esp)->error;
123 static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
125 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
129 if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
132 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
138 printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
139 esp_read8(ESP_STATUS));
144 static inline int mac_esp_wait_for_dreq(struct esp *esp)
146 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
150 if (mep->pdma_regs == NULL) {
151 if (mac_irq_pending(IRQ_MAC_SCSIDRQ))
154 if (nubus_readl(mep->pdma_regs) & 0x200)
158 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
164 printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
165 esp_read8(ESP_STATUS));
170 #define MAC_ESP_PDMA_LOOP(operands) \
174 "1: movew " operands " \n" \
175 "2: movew " operands " \n" \
176 "3: movew " operands " \n" \
177 "4: movew " operands " \n" \
178 "5: movew " operands " \n" \
179 "6: movew " operands " \n" \
180 "7: movew " operands " \n" \
181 "8: movew " operands " \n" \
182 "9: movew " operands " \n" \
183 "10: movew " operands " \n" \
184 "11: movew " operands " \n" \
185 "12: movew " operands " \n" \
186 "13: movew " operands " \n" \
187 "14: movew " operands " \n" \
188 "15: movew " operands " \n" \
189 "16: movew " operands " \n" \
194 "21: movew " operands " \n" \
199 "31: moveb " operands " \n" \
203 " .section __ex_table,\"a\" \n" \
214 " .long 10b,40b \n" \
215 " .long 11b,40b \n" \
216 " .long 12b,40b \n" \
217 " .long 13b,40b \n" \
218 " .long 14b,40b \n" \
219 " .long 15b,40b \n" \
220 " .long 16b,40b \n" \
221 " .long 21b,40b \n" \
222 " .long 31b,40b \n" \
223 " .long 32b,40b \n" \
225 : "+a" (addr), "+r" (count32), "+r" (count2) \
226 : "g" (count1), "a" (mep->pdma_io))
228 static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
229 u32 dma_count, int write, u8 cmd)
231 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
234 local_irq_save(flags);
239 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
241 esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
242 esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
244 scsi_esp_cmd(esp, cmd);
247 unsigned int count32 = esp_count >> 5;
248 unsigned int count2 = (esp_count & 0x1F) >> 1;
249 unsigned int count1 = esp_count & 1;
250 unsigned int start_addr = addr;
252 if (mac_esp_wait_for_dreq(esp))
256 MAC_ESP_PDMA_LOOP("%4@,%0@+");
258 esp_count -= addr - start_addr;
262 MAC_ESP_PDMA_LOOP("%0@+,%4@");
264 if (mac_esp_wait_for_empty_fifo(esp))
267 n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
268 addr = start_addr + esp_count - n;
273 local_irq_restore(flags);
277 * Programmed IO routines follow.
280 static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
285 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
293 printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
294 esp_read8(ESP_STATUS));
298 static inline int mac_esp_wait_for_intr(struct esp *esp)
300 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
304 esp->sreg = esp_read8(ESP_STATUS);
305 if (esp->sreg & ESP_STAT_INTR)
311 printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
316 #define MAC_ESP_PIO_LOOP(operands, reg1) \
318 "1: moveb " operands " \n" \
321 : "+a" (addr), "+r" (reg1) \
324 #define MAC_ESP_PIO_FILL(operands, reg1) \
326 " moveb " operands " \n" \
327 " moveb " operands " \n" \
328 " moveb " operands " \n" \
329 " moveb " operands " \n" \
330 " moveb " operands " \n" \
331 " moveb " operands " \n" \
332 " moveb " operands " \n" \
333 " moveb " operands " \n" \
334 " moveb " operands " \n" \
335 " moveb " operands " \n" \
336 " moveb " operands " \n" \
337 " moveb " operands " \n" \
338 " moveb " operands " \n" \
339 " moveb " operands " \n" \
340 " moveb " operands " \n" \
341 " moveb " operands " \n" \
344 : "+a" (addr), "+r" (reg1) \
347 #define MAC_ESP_FIFO_SIZE 16
349 static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
350 u32 dma_count, int write, u8 cmd)
352 struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
353 u8 *fifo = esp->regs + ESP_FDATA * 16;
355 disable_irq(esp->host->irq);
361 scsi_esp_cmd(esp, cmd);
366 n = mac_esp_wait_for_fifo(esp);
374 MAC_ESP_PIO_LOOP("%2@,%0@+", n);
379 if (mac_esp_wait_for_intr(esp))
382 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
383 ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
386 esp->ireg = esp_read8(ESP_INTRPT);
387 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
391 scsi_esp_cmd(esp, ESP_CMD_TI);
394 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
396 if (esp_count >= MAC_ESP_FIFO_SIZE)
397 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
399 MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);
401 scsi_esp_cmd(esp, cmd);
406 if (mac_esp_wait_for_intr(esp))
409 if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
410 ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
413 esp->ireg = esp_read8(ESP_INTRPT);
414 if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
418 n = MAC_ESP_FIFO_SIZE -
419 (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
423 if (n == MAC_ESP_FIFO_SIZE) {
424 MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
427 MAC_ESP_PIO_LOOP("%0@+,%2@", n);
430 scsi_esp_cmd(esp, ESP_CMD_TI);
434 enable_irq(esp->host->irq);
437 static int mac_esp_irq_pending(struct esp *esp)
439 if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
444 static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
446 return dma_len > 0xFFFF ? 0xFFFF : dma_len;
449 static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
454 * This is an edge triggered IRQ, so we have to be careful to
455 * avoid missing a transition when it is shared by two ESP devices.
461 (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
462 (void)scsi_esp_intr(irq, esp_chips[0]);
466 (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
467 (void)scsi_esp_intr(irq, esp_chips[1]);
475 static struct esp_driver_ops mac_esp_ops = {
476 .esp_write8 = mac_esp_write8,
477 .esp_read8 = mac_esp_read8,
478 .map_single = mac_esp_map_single,
479 .map_sg = mac_esp_map_sg,
480 .unmap_single = mac_esp_unmap_single,
481 .unmap_sg = mac_esp_unmap_sg,
482 .irq_pending = mac_esp_irq_pending,
483 .dma_length_limit = mac_esp_dma_length_limit,
484 .reset_dma = mac_esp_reset_dma,
485 .dma_drain = mac_esp_dma_drain,
486 .dma_invalidate = mac_esp_dma_invalidate,
487 .send_dma_cmd = mac_esp_send_pdma_cmd,
488 .dma_error = mac_esp_dma_error,
491 static int __devinit esp_mac_probe(struct platform_device *dev)
493 struct scsi_host_template *tpnt = &scsi_esp_template;
494 struct Scsi_Host *host;
497 struct mac_esp_priv *mep;
505 host = scsi_host_alloc(tpnt, sizeof(struct esp));
512 host->use_clustering = DISABLE_CLUSTERING;
513 esp = shost_priv(host);
518 esp->command_block = kzalloc(16, GFP_KERNEL);
519 if (!esp->command_block)
521 esp->command_block_dma = (dma_addr_t)esp->command_block;
524 host->this_id = esp->scsi_id;
525 esp->scsi_id_mask = 1 << esp->scsi_id;
527 mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
529 goto fail_free_command_block;
531 platform_set_drvdata(dev, mep);
533 switch (macintosh_config->scsi_type) {
534 case MAC_SCSI_QUADRA:
535 esp->cfreq = 16500000;
536 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA;
537 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
538 mep->pdma_regs = NULL;
540 case MAC_SCSI_QUADRA2:
541 esp->cfreq = 25000000;
542 esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
543 dev->id * MAC_ESP_REGS_SPACING);
544 mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
545 mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
546 dev->id * MAC_ESP_PDMA_REG_SPACING);
547 nubus_writel(0x1d1, mep->pdma_regs);
549 case MAC_SCSI_QUADRA3:
550 /* These quadras have a real DMA controller (the PSC) but we
551 * don't know how to drive it so we must use PIO instead.
553 esp->cfreq = 25000000;
554 esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3;
556 mep->pdma_regs = NULL;
560 esp->ops = &mac_esp_ops;
561 if (mep->pdma_io == NULL) {
562 printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
563 esp_write8(0, ESP_TCLOW);
564 esp_write8(0, ESP_TCMED);
565 esp->flags = ESP_FLAG_DISABLE_SYNC;
566 mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
568 printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
571 host->irq = IRQ_MAC_SCSI;
572 esp_chips[dev->id] = esp;
574 if (esp_chips[!dev->id] == NULL) {
575 err = request_irq(host->irq, mac_scsi_esp_intr, 0,
578 esp_chips[dev->id] = NULL;
583 err = scsi_esp_register(esp, &dev->dev);
590 if (esp_chips[!dev->id] == NULL)
591 free_irq(host->irq, esp);
594 fail_free_command_block:
595 kfree(esp->command_block);
602 static int __devexit esp_mac_remove(struct platform_device *dev)
604 struct mac_esp_priv *mep = platform_get_drvdata(dev);
605 struct esp *esp = mep->esp;
606 unsigned int irq = esp->host->irq;
608 scsi_esp_unregister(esp);
610 esp_chips[dev->id] = NULL;
611 if (!(esp_chips[0] || esp_chips[1]))
616 kfree(esp->command_block);
618 scsi_host_put(esp->host);
623 static struct platform_driver esp_mac_driver = {
624 .probe = esp_mac_probe,
625 .remove = __devexit_p(esp_mac_remove),
627 .name = DRV_MODULE_NAME,
628 .owner = THIS_MODULE,
632 static int __init mac_esp_init(void)
634 return platform_driver_register(&esp_mac_driver);
637 static void __exit mac_esp_exit(void)
639 platform_driver_unregister(&esp_mac_driver);
642 MODULE_DESCRIPTION("Mac ESP SCSI driver");
644 MODULE_LICENSE("GPL v2");
645 MODULE_VERSION(DRV_VERSION);
646 MODULE_ALIAS("platform:" DRV_MODULE_NAME);
648 module_init(mac_esp_init);
649 module_exit(mac_esp_exit);