xref: /openbmc/linux/drivers/scsi/mvme147.c (revision 9a29f5fc)
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/scsi.h>
15 #include <scsi/scsi_cmnd.h>
16 #include <scsi/scsi_device.h>
17 #include <scsi/scsi_eh.h>
18 #include <scsi/scsi_host.h>
19 #include <scsi/scsi_tcq.h>
20 #include "wd33c93.h"
21 #include "mvme147.h"
22 
23 static irqreturn_t mvme147_intr(int irq, void *data)
24 {
25 	struct Scsi_Host *instance = data;
26 
27 	if (irq == MVME147_IRQ_SCSI_PORT)
28 		wd33c93_intr(instance);
29 	else
30 		m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
31 	return IRQ_HANDLED;
32 }
33 
34 static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
35 {
36 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
37 	struct Scsi_Host *instance = cmd->device->host;
38 	struct WD33C93_hostdata *hdata = shost_priv(instance);
39 	unsigned char flags = 0x01;
40 	unsigned long addr = virt_to_bus(scsi_pointer->ptr);
41 
42 	/* setup dma direction */
43 	if (!dir_in)
44 		flags |= 0x04;
45 
46 	/* remember direction */
47 	hdata->dma_dir = dir_in;
48 
49 	if (dir_in) {
50 		/* invalidate any cache */
51 		cache_clear(addr, scsi_pointer->this_residual);
52 	} else {
53 		/* push any dirty cache */
54 		cache_push(addr, scsi_pointer->this_residual);
55 	}
56 
57 	/* start DMA */
58 	m147_pcc->dma_bcr = scsi_pointer->this_residual | (1 << 24);
59 	m147_pcc->dma_dadr = addr;
60 	m147_pcc->dma_cntrl = flags;
61 
62 	/* return success */
63 	return 0;
64 }
65 
66 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
67 		     int status)
68 {
69 	m147_pcc->dma_cntrl = 0;
70 }
71 
72 static struct scsi_host_template mvme147_host_template = {
73 	.module			= THIS_MODULE,
74 	.proc_name		= "MVME147",
75 	.name			= "MVME147 built-in SCSI",
76 	.queuecommand		= wd33c93_queuecommand,
77 	.eh_abort_handler	= wd33c93_abort,
78 	.eh_host_reset_handler	= wd33c93_host_reset,
79 	.show_info		= wd33c93_show_info,
80 	.write_info		= wd33c93_write_info,
81 	.can_queue		= CAN_QUEUE,
82 	.this_id		= 7,
83 	.sg_tablesize		= SG_ALL,
84 	.cmd_per_lun		= CMD_PER_LUN,
85 	.cmd_size		= sizeof(struct scsi_pointer),
86 };
87 
88 static struct Scsi_Host *mvme147_shost;
89 
90 static int __init mvme147_init(void)
91 {
92 	wd33c93_regs regs;
93 	struct WD33C93_hostdata *hdata;
94 	int error = -ENOMEM;
95 
96 	if (!MACH_IS_MVME147)
97 		return 0;
98 
99 	mvme147_shost = scsi_host_alloc(&mvme147_host_template,
100 			sizeof(struct WD33C93_hostdata));
101 	if (!mvme147_shost)
102 		goto err_out;
103 	mvme147_shost->base = 0xfffe4000;
104 	mvme147_shost->irq = MVME147_IRQ_SCSI_PORT;
105 
106 	regs.SASR = (volatile unsigned char *)0xfffe4000;
107 	regs.SCMD = (volatile unsigned char *)0xfffe4001;
108 
109 	hdata = shost_priv(mvme147_shost);
110 	hdata->no_sync = 0xff;
111 	hdata->fast = 0;
112 	hdata->dma_mode = CTRL_DMA;
113 
114 	wd33c93_init(mvme147_shost, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
115 
116 	error = request_irq(MVME147_IRQ_SCSI_PORT, mvme147_intr, 0,
117 			"MVME147 SCSI PORT", mvme147_shost);
118 	if (error)
119 		goto err_unregister;
120 	error = request_irq(MVME147_IRQ_SCSI_DMA, mvme147_intr, 0,
121 			"MVME147 SCSI DMA", mvme147_shost);
122 	if (error)
123 		goto err_free_irq;
124 #if 0	/* Disabled; causes problems booting */
125 	m147_pcc->scsi_interrupt = 0x10;	/* Assert SCSI bus reset */
126 	udelay(100);
127 	m147_pcc->scsi_interrupt = 0x00;	/* Negate SCSI bus reset */
128 	udelay(2000);
129 	m147_pcc->scsi_interrupt = 0x40;	/* Clear bus reset interrupt */
130 #endif
131 	m147_pcc->scsi_interrupt = 0x09;	/* Enable interrupt */
132 
133 	m147_pcc->dma_cntrl = 0x00;	/* ensure DMA is stopped */
134 	m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
135 
136 	error = scsi_add_host(mvme147_shost, NULL);
137 	if (error)
138 		goto err_free_irq;
139 	scsi_scan_host(mvme147_shost);
140 	return 0;
141 
142 err_free_irq:
143 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
144 err_unregister:
145 	scsi_host_put(mvme147_shost);
146 err_out:
147 	return error;
148 }
149 
150 static void __exit mvme147_exit(void)
151 {
152 	scsi_remove_host(mvme147_shost);
153 
154 	/* XXX Make sure DMA is stopped! */
155 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
156 	free_irq(MVME147_IRQ_SCSI_DMA, mvme147_shost);
157 
158 	scsi_host_put(mvme147_shost);
159 }
160 
161 module_init(mvme147_init);
162 module_exit(mvme147_exit);
163