xref: /linux/drivers/scsi/mvme147.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/mm.h>
4 #include <linux/blkdev.h>
5 #include <linux/interrupt.h>
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 
10 #include <asm/page.h>
11 #include <asm/mvme147hw.h>
12 #include <asm/irq.h>
13 
14 #include "scsi.h"
15 #include <scsi/scsi_host.h>
16 #include "wd33c93.h"
17 #include "mvme147.h"
18 
19 static irqreturn_t mvme147_intr(int irq, void *data)
20 {
21 	struct Scsi_Host *instance = data;
22 
23 	if (irq == MVME147_IRQ_SCSI_PORT)
24 		wd33c93_intr(instance);
25 	else
26 		m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
27 	return IRQ_HANDLED;
28 }
29 
30 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
31 {
32 	struct Scsi_Host *instance = cmd->device->host;
33 	struct WD33C93_hostdata *hdata = shost_priv(instance);
34 	unsigned char flags = 0x01;
35 	unsigned long addr = virt_to_bus(cmd->SCp.ptr);
36 
37 	/* setup dma direction */
38 	if (!dir_in)
39 		flags |= 0x04;
40 
41 	/* remember direction */
42 	hdata->dma_dir = dir_in;
43 
44 	if (dir_in) {
45 		/* invalidate any cache */
46 		cache_clear(addr, cmd->SCp.this_residual);
47 	} else {
48 		/* push any dirty cache */
49 		cache_push(addr, cmd->SCp.this_residual);
50 	}
51 
52 	/* start DMA */
53 	m147_pcc->dma_bcr = cmd->SCp.this_residual | (1 << 24);
54 	m147_pcc->dma_dadr = addr;
55 	m147_pcc->dma_cntrl = flags;
56 
57 	/* return success */
58 	return 0;
59 }
60 
61 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
62 		     int status)
63 {
64 	m147_pcc->dma_cntrl = 0;
65 }
66 
67 static struct scsi_host_template mvme147_host_template = {
68 	.module			= THIS_MODULE,
69 	.proc_name		= "MVME147",
70 	.name			= "MVME147 built-in SCSI",
71 	.queuecommand		= wd33c93_queuecommand,
72 	.eh_abort_handler	= wd33c93_abort,
73 	.eh_host_reset_handler	= wd33c93_host_reset,
74 	.show_info		= wd33c93_show_info,
75 	.write_info		= wd33c93_write_info,
76 	.can_queue		= CAN_QUEUE,
77 	.this_id		= 7,
78 	.sg_tablesize		= SG_ALL,
79 	.cmd_per_lun		= CMD_PER_LUN,
80 };
81 
82 static struct Scsi_Host *mvme147_shost;
83 
84 static int __init mvme147_init(void)
85 {
86 	wd33c93_regs regs;
87 	struct WD33C93_hostdata *hdata;
88 	int error = -ENOMEM;
89 
90 	if (!MACH_IS_MVME147)
91 		return 0;
92 
93 	mvme147_shost = scsi_host_alloc(&mvme147_host_template,
94 			sizeof(struct WD33C93_hostdata));
95 	if (!mvme147_shost)
96 		goto err_out;
97 	mvme147_shost->base = 0xfffe4000;
98 	mvme147_shost->irq = MVME147_IRQ_SCSI_PORT;
99 
100 	regs.SASR = (volatile unsigned char *)0xfffe4000;
101 	regs.SCMD = (volatile unsigned char *)0xfffe4001;
102 
103 	hdata = shost_priv(mvme147_shost);
104 	hdata->no_sync = 0xff;
105 	hdata->fast = 0;
106 	hdata->dma_mode = CTRL_DMA;
107 
108 	wd33c93_init(mvme147_shost, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
109 
110 	error = request_irq(MVME147_IRQ_SCSI_PORT, mvme147_intr, 0,
111 			"MVME147 SCSI PORT", mvme147_shost);
112 	if (error)
113 		goto err_unregister;
114 	error = request_irq(MVME147_IRQ_SCSI_DMA, mvme147_intr, 0,
115 			"MVME147 SCSI DMA", mvme147_shost);
116 	if (error)
117 		goto err_free_irq;
118 #if 0	/* Disabled; causes problems booting */
119 	m147_pcc->scsi_interrupt = 0x10;	/* Assert SCSI bus reset */
120 	udelay(100);
121 	m147_pcc->scsi_interrupt = 0x00;	/* Negate SCSI bus reset */
122 	udelay(2000);
123 	m147_pcc->scsi_interrupt = 0x40;	/* Clear bus reset interrupt */
124 #endif
125 	m147_pcc->scsi_interrupt = 0x09;	/* Enable interrupt */
126 
127 	m147_pcc->dma_cntrl = 0x00;	/* ensure DMA is stopped */
128 	m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
129 
130 	error = scsi_add_host(mvme147_shost, NULL);
131 	if (error)
132 		goto err_free_irq;
133 	scsi_scan_host(mvme147_shost);
134 	return 0;
135 
136 err_free_irq:
137 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
138 err_unregister:
139 	scsi_host_put(mvme147_shost);
140 err_out:
141 	return error;
142 }
143 
144 static void __exit mvme147_exit(void)
145 {
146 	scsi_remove_host(mvme147_shost);
147 
148 	/* XXX Make sure DMA is stopped! */
149 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
150 	free_irq(MVME147_IRQ_SCSI_DMA, mvme147_shost);
151 
152 	scsi_host_put(mvme147_shost);
153 }
154 
155 module_init(mvme147_init);
156 module_exit(mvme147_exit);
157