1 // SPDX-License-Identifier: GPL-2.0-only
2 /* mac_esp.c: ESP front-end for Macintosh Quadra systems.
4 * Adapted from jazz_esp.c and the old mac_esp.c.
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.
9 * Copyright (C) 2007-2008 Finn Thain
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>
22 #include <linux/nubus.h>
23 #include <linux/slab.h>
27 #include <asm/macints.h>
28 #include <asm/macintosh.h>
29 #include <asm/mac_via.h>
31 #include <scsi/scsi_host.h>
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"
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
49 #define esp_read8(REG) mac_esp_read8(esp, REG)
50 #define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG)
54 void __iomem
*pdma_regs
;
55 void __iomem
*pdma_io
;
57 static struct esp
*esp_chips
[2];
58 static DEFINE_SPINLOCK(esp_chips_lock
);
60 #define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
61 dev_get_drvdata((esp)->dev))
63 static inline void mac_esp_write8(struct esp
*esp
, u8 val
, unsigned long reg
)
65 nubus_writeb(val
, esp
->regs
+ reg
* 16);
68 static inline u8
mac_esp_read8(struct esp
*esp
, unsigned long reg
)
70 return nubus_readb(esp
->regs
+ reg
* 16);
73 static void mac_esp_reset_dma(struct esp
*esp
)
78 static void mac_esp_dma_drain(struct esp
*esp
)
83 static void mac_esp_dma_invalidate(struct esp
*esp
)
88 static int mac_esp_dma_error(struct esp
*esp
)
90 return esp
->send_cmd_error
;
93 static inline int mac_esp_wait_for_empty_fifo(struct esp
*esp
)
98 if (!(esp_read8(ESP_FFLAGS
) & ESP_FF_FBYTES
))
101 if (esp_read8(ESP_STATUS
) & ESP_STAT_INTR
)
107 printk(KERN_ERR PFX
"FIFO is not empty (sreg %02x)\n",
108 esp_read8(ESP_STATUS
));
109 esp
->send_cmd_error
= 1;
113 static inline int mac_esp_wait_for_dreq(struct esp
*esp
)
115 struct mac_esp_priv
*mep
= MAC_ESP_GET_PRIV(esp
);
119 if (mep
->pdma_regs
== NULL
) {
120 if (via2_scsi_drq_pending())
123 if (nubus_readl(mep
->pdma_regs
) & 0x200)
127 if (esp_read8(ESP_STATUS
) & ESP_STAT_INTR
)
133 printk(KERN_ERR PFX
"PDMA timeout (sreg %02x)\n",
134 esp_read8(ESP_STATUS
));
135 esp
->send_cmd_error
= 1;
139 #define MAC_ESP_PDMA_LOOP(operands) \
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" \
163 "21: movew " operands " \n" \
168 "31: moveb " operands " \n" \
172 " .section __ex_table,\"a\" \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" \
194 : "+a" (addr), "+r" (count32), "+r" (count2) \
195 : "g" (count1), "a" (mep->pdma_io))
197 static void mac_esp_send_pdma_cmd(struct esp
*esp
, u32 addr
, u32 esp_count
,
198 u32 dma_count
, int write
, u8 cmd
)
200 struct mac_esp_priv
*mep
= MAC_ESP_GET_PRIV(esp
);
202 esp
->send_cmd_error
= 0;
205 scsi_esp_cmd(esp
, ESP_CMD_FLUSH
);
207 esp_write8((esp_count
>> 0) & 0xFF, ESP_TCLOW
);
208 esp_write8((esp_count
>> 8) & 0xFF, ESP_TCMED
);
210 scsi_esp_cmd(esp
, cmd
);
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
;
218 if (mac_esp_wait_for_dreq(esp
))
222 MAC_ESP_PDMA_LOOP("%4@,%0@+");
224 esp_count
-= addr
- start_addr
;
228 MAC_ESP_PDMA_LOOP("%0@+,%4@");
230 if (mac_esp_wait_for_empty_fifo(esp
))
233 n
= (esp_read8(ESP_TCMED
) << 8) + esp_read8(ESP_TCLOW
);
234 addr
= start_addr
+ esp_count
- n
;
240 static int mac_esp_irq_pending(struct esp
*esp
)
242 if (esp_read8(ESP_STATUS
) & ESP_STAT_INTR
)
247 static u32
mac_esp_dma_length_limit(struct esp
*esp
, u32 dma_addr
, u32 dma_len
)
249 return dma_len
> 0xFFFF ? 0xFFFF : dma_len
;
252 static irqreturn_t
mac_scsi_esp_intr(int irq
, void *dev_id
)
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.
264 (mac_esp_read8(esp_chips
[0], ESP_STATUS
) & ESP_STAT_INTR
)) {
265 (void)scsi_esp_intr(irq
, esp_chips
[0]);
269 (mac_esp_read8(esp_chips
[1], ESP_STATUS
) & ESP_STAT_INTR
)) {
270 (void)scsi_esp_intr(irq
, esp_chips
[1]);
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
,
290 static int esp_mac_probe(struct platform_device
*dev
)
292 struct scsi_host_template
*tpnt
= &scsi_esp_template
;
293 struct Scsi_Host
*host
;
296 struct mac_esp_priv
*mep
;
304 host
= scsi_host_alloc(tpnt
, sizeof(struct esp
));
311 host
->dma_boundary
= PAGE_SIZE
- 1;
312 esp
= shost_priv(host
);
315 esp
->dev
= &dev
->dev
;
317 esp
->command_block
= kzalloc(16, GFP_KERNEL
);
318 if (!esp
->command_block
)
320 esp
->command_block_dma
= (dma_addr_t
)esp
->command_block
;
323 host
->this_id
= esp
->scsi_id
;
324 esp
->scsi_id_mask
= 1 << esp
->scsi_id
;
326 mep
= kzalloc(sizeof(struct mac_esp_priv
), GFP_KERNEL
);
328 goto fail_free_command_block
;
330 platform_set_drvdata(dev
, mep
);
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
;
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
);
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.
352 esp
->cfreq
= 25000000;
353 esp
->regs
= (void __iomem
*)MAC_ESP_REGS_QUADRA3
;
355 mep
->pdma_regs
= NULL
;
358 esp
->fifo_reg
= esp
->regs
+ ESP_FDATA
* 16;
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
;
369 printk(KERN_INFO PFX
"using PDMA for controller %d\n", dev
->id
);
372 host
->irq
= IRQ_MAC_SCSI
;
374 /* The request_irq() call is intended to succeed for the first device
375 * and fail for the second device.
377 err
= request_irq(host
->irq
, mac_scsi_esp_intr
, 0, "ESP", NULL
);
378 spin_lock(&esp_chips_lock
);
379 if (err
< 0 && esp_chips
[!dev
->id
] == NULL
) {
380 spin_unlock(&esp_chips_lock
);
383 esp_chips
[dev
->id
] = esp
;
384 spin_unlock(&esp_chips_lock
);
386 err
= scsi_esp_register(esp
);
393 spin_lock(&esp_chips_lock
);
394 esp_chips
[dev
->id
] = NULL
;
395 if (esp_chips
[!dev
->id
] == NULL
) {
396 spin_unlock(&esp_chips_lock
);
397 free_irq(host
->irq
, NULL
);
399 spin_unlock(&esp_chips_lock
);
402 fail_free_command_block
:
403 kfree(esp
->command_block
);
410 static int esp_mac_remove(struct platform_device
*dev
)
412 struct mac_esp_priv
*mep
= platform_get_drvdata(dev
);
413 struct esp
*esp
= mep
->esp
;
414 unsigned int irq
= esp
->host
->irq
;
416 scsi_esp_unregister(esp
);
418 spin_lock(&esp_chips_lock
);
419 esp_chips
[dev
->id
] = NULL
;
420 if (esp_chips
[!dev
->id
] == NULL
) {
421 spin_unlock(&esp_chips_lock
);
424 spin_unlock(&esp_chips_lock
);
428 kfree(esp
->command_block
);
430 scsi_host_put(esp
->host
);
435 static struct platform_driver esp_mac_driver
= {
436 .probe
= esp_mac_probe
,
437 .remove
= esp_mac_remove
,
439 .name
= DRV_MODULE_NAME
,
443 static int __init
mac_esp_init(void)
445 return platform_driver_register(&esp_mac_driver
);
448 static void __exit
mac_esp_exit(void)
450 platform_driver_unregister(&esp_mac_driver
);
453 MODULE_DESCRIPTION("Mac ESP SCSI driver");
454 MODULE_AUTHOR("Finn Thain");
455 MODULE_LICENSE("GPL v2");
456 MODULE_VERSION(DRV_VERSION
);
457 MODULE_ALIAS("platform:" DRV_MODULE_NAME
);
459 module_init(mac_esp_init
);
460 module_exit(mac_esp_exit
);