xref: /openbmc/linux/drivers/scsi/mvme147.c (revision 3b23dc52)
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/pgtable.h>
12 #include <asm/mvme147hw.h>
13 #include <asm/irq.h>
14 
15 #include "scsi.h"
16 #include <scsi/scsi_host.h>
17 #include "wd33c93.h"
18 #include "mvme147.h"
19 
20 static irqreturn_t mvme147_intr(int irq, void *data)
21 {
22 	struct Scsi_Host *instance = data;
23 
24 	if (irq == MVME147_IRQ_SCSI_PORT)
25 		wd33c93_intr(instance);
26 	else
27 		m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
28 	return IRQ_HANDLED;
29 }
30 
31 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
32 {
33 	struct Scsi_Host *instance = cmd->device->host;
34 	struct WD33C93_hostdata *hdata = shost_priv(instance);
35 	unsigned char flags = 0x01;
36 	unsigned long addr = virt_to_bus(cmd->SCp.ptr);
37 
38 	/* setup dma direction */
39 	if (!dir_in)
40 		flags |= 0x04;
41 
42 	/* remember direction */
43 	hdata->dma_dir = dir_in;
44 
45 	if (dir_in) {
46 		/* invalidate any cache */
47 		cache_clear(addr, cmd->SCp.this_residual);
48 	} else {
49 		/* push any dirty cache */
50 		cache_push(addr, cmd->SCp.this_residual);
51 	}
52 
53 	/* start DMA */
54 	m147_pcc->dma_bcr = cmd->SCp.this_residual | (1 << 24);
55 	m147_pcc->dma_dadr = addr;
56 	m147_pcc->dma_cntrl = flags;
57 
58 	/* return success */
59 	return 0;
60 }
61 
62 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
63 		     int status)
64 {
65 	m147_pcc->dma_cntrl = 0;
66 }
67 
68 static struct scsi_host_template mvme147_host_template = {
69 	.module			= THIS_MODULE,
70 	.proc_name		= "MVME147",
71 	.name			= "MVME147 built-in SCSI",
72 	.queuecommand		= wd33c93_queuecommand,
73 	.eh_abort_handler	= wd33c93_abort,
74 	.eh_host_reset_handler	= wd33c93_host_reset,
75 	.show_info		= wd33c93_show_info,
76 	.write_info		= wd33c93_write_info,
77 	.can_queue		= CAN_QUEUE,
78 	.this_id		= 7,
79 	.sg_tablesize		= SG_ALL,
80 	.cmd_per_lun		= CMD_PER_LUN,
81 	.use_clustering		= ENABLE_CLUSTERING
82 };
83 
84 static struct Scsi_Host *mvme147_shost;
85 
86 static int __init mvme147_init(void)
87 {
88 	wd33c93_regs regs;
89 	struct WD33C93_hostdata *hdata;
90 	int error = -ENOMEM;
91 
92 	if (!MACH_IS_MVME147)
93 		return 0;
94 
95 	mvme147_shost = scsi_host_alloc(&mvme147_host_template,
96 			sizeof(struct WD33C93_hostdata));
97 	if (!mvme147_shost)
98 		goto err_out;
99 	mvme147_shost->base = 0xfffe4000;
100 	mvme147_shost->irq = MVME147_IRQ_SCSI_PORT;
101 
102 	regs.SASR = (volatile unsigned char *)0xfffe4000;
103 	regs.SCMD = (volatile unsigned char *)0xfffe4001;
104 
105 	hdata = shost_priv(mvme147_shost);
106 	hdata->no_sync = 0xff;
107 	hdata->fast = 0;
108 	hdata->dma_mode = CTRL_DMA;
109 
110 	wd33c93_init(mvme147_shost, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
111 
112 	error = request_irq(MVME147_IRQ_SCSI_PORT, mvme147_intr, 0,
113 			"MVME147 SCSI PORT", mvme147_shost);
114 	if (error)
115 		goto err_unregister;
116 	error = request_irq(MVME147_IRQ_SCSI_DMA, mvme147_intr, 0,
117 			"MVME147 SCSI DMA", mvme147_shost);
118 	if (error)
119 		goto err_free_irq;
120 #if 0	/* Disabled; causes problems booting */
121 	m147_pcc->scsi_interrupt = 0x10;	/* Assert SCSI bus reset */
122 	udelay(100);
123 	m147_pcc->scsi_interrupt = 0x00;	/* Negate SCSI bus reset */
124 	udelay(2000);
125 	m147_pcc->scsi_interrupt = 0x40;	/* Clear bus reset interrupt */
126 #endif
127 	m147_pcc->scsi_interrupt = 0x09;	/* Enable interrupt */
128 
129 	m147_pcc->dma_cntrl = 0x00;	/* ensure DMA is stopped */
130 	m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
131 
132 	error = scsi_add_host(mvme147_shost, NULL);
133 	if (error)
134 		goto err_free_irq;
135 	scsi_scan_host(mvme147_shost);
136 	return 0;
137 
138 err_free_irq:
139 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
140 err_unregister:
141 	scsi_host_put(mvme147_shost);
142 err_out:
143 	return error;
144 }
145 
146 static void __exit mvme147_exit(void)
147 {
148 	scsi_remove_host(mvme147_shost);
149 
150 	/* XXX Make sure DMA is stopped! */
151 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
152 	free_irq(MVME147_IRQ_SCSI_DMA, mvme147_shost);
153 
154 	scsi_host_put(mvme147_shost);
155 }
156 
157 module_init(mvme147_init);
158 module_exit(mvme147_exit);
159