xref: /openbmc/linux/drivers/scsi/mvme147.c (revision 53555fb7bceb14f5fdb9358290daf64d0ea0f56a)
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_Host *instance = cmd->device->host;
37 	struct WD33C93_hostdata *hdata = shost_priv(instance);
38 	unsigned char flags = 0x01;
39 	unsigned long addr = virt_to_bus(cmd->SCp.ptr);
40 
41 	/* setup dma direction */
42 	if (!dir_in)
43 		flags |= 0x04;
44 
45 	/* remember direction */
46 	hdata->dma_dir = dir_in;
47 
48 	if (dir_in) {
49 		/* invalidate any cache */
50 		cache_clear(addr, cmd->SCp.this_residual);
51 	} else {
52 		/* push any dirty cache */
53 		cache_push(addr, cmd->SCp.this_residual);
54 	}
55 
56 	/* start DMA */
57 	m147_pcc->dma_bcr = cmd->SCp.this_residual | (1 << 24);
58 	m147_pcc->dma_dadr = addr;
59 	m147_pcc->dma_cntrl = flags;
60 
61 	/* return success */
62 	return 0;
63 }
64 
65 static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
66 		     int status)
67 {
68 	m147_pcc->dma_cntrl = 0;
69 }
70 
71 static struct scsi_host_template mvme147_host_template = {
72 	.module			= THIS_MODULE,
73 	.proc_name		= "MVME147",
74 	.name			= "MVME147 built-in SCSI",
75 	.queuecommand		= wd33c93_queuecommand,
76 	.eh_abort_handler	= wd33c93_abort,
77 	.eh_host_reset_handler	= wd33c93_host_reset,
78 	.show_info		= wd33c93_show_info,
79 	.write_info		= wd33c93_write_info,
80 	.can_queue		= CAN_QUEUE,
81 	.this_id		= 7,
82 	.sg_tablesize		= SG_ALL,
83 	.cmd_per_lun		= CMD_PER_LUN,
84 };
85 
86 static struct Scsi_Host *mvme147_shost;
87 
88 static int __init mvme147_init(void)
89 {
90 	wd33c93_regs regs;
91 	struct WD33C93_hostdata *hdata;
92 	int error = -ENOMEM;
93 
94 	if (!MACH_IS_MVME147)
95 		return 0;
96 
97 	mvme147_shost = scsi_host_alloc(&mvme147_host_template,
98 			sizeof(struct WD33C93_hostdata));
99 	if (!mvme147_shost)
100 		goto err_out;
101 	mvme147_shost->base = 0xfffe4000;
102 	mvme147_shost->irq = MVME147_IRQ_SCSI_PORT;
103 
104 	regs.SASR = (volatile unsigned char *)0xfffe4000;
105 	regs.SCMD = (volatile unsigned char *)0xfffe4001;
106 
107 	hdata = shost_priv(mvme147_shost);
108 	hdata->no_sync = 0xff;
109 	hdata->fast = 0;
110 	hdata->dma_mode = CTRL_DMA;
111 
112 	wd33c93_init(mvme147_shost, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
113 
114 	error = request_irq(MVME147_IRQ_SCSI_PORT, mvme147_intr, 0,
115 			"MVME147 SCSI PORT", mvme147_shost);
116 	if (error)
117 		goto err_unregister;
118 	error = request_irq(MVME147_IRQ_SCSI_DMA, mvme147_intr, 0,
119 			"MVME147 SCSI DMA", mvme147_shost);
120 	if (error)
121 		goto err_free_irq;
122 #if 0	/* Disabled; causes problems booting */
123 	m147_pcc->scsi_interrupt = 0x10;	/* Assert SCSI bus reset */
124 	udelay(100);
125 	m147_pcc->scsi_interrupt = 0x00;	/* Negate SCSI bus reset */
126 	udelay(2000);
127 	m147_pcc->scsi_interrupt = 0x40;	/* Clear bus reset interrupt */
128 #endif
129 	m147_pcc->scsi_interrupt = 0x09;	/* Enable interrupt */
130 
131 	m147_pcc->dma_cntrl = 0x00;	/* ensure DMA is stopped */
132 	m147_pcc->dma_intr = 0x89;	/* Ack and enable ints */
133 
134 	error = scsi_add_host(mvme147_shost, NULL);
135 	if (error)
136 		goto err_free_irq;
137 	scsi_scan_host(mvme147_shost);
138 	return 0;
139 
140 err_free_irq:
141 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
142 err_unregister:
143 	scsi_host_put(mvme147_shost);
144 err_out:
145 	return error;
146 }
147 
148 static void __exit mvme147_exit(void)
149 {
150 	scsi_remove_host(mvme147_shost);
151 
152 	/* XXX Make sure DMA is stopped! */
153 	free_irq(MVME147_IRQ_SCSI_PORT, mvme147_shost);
154 	free_irq(MVME147_IRQ_SCSI_DMA, mvme147_shost);
155 
156 	scsi_host_put(mvme147_shost);
157 }
158 
159 module_init(mvme147_init);
160 module_exit(mvme147_exit);
161