xref: /openbmc/linux/drivers/scsi/jazz_esp.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* jazz_esp.c: ESP front-end for MIPS JAZZ systems.
3  *
4  * Copyright (C) 2007 Thomas Bogendörfer (tsbogend@alpha.frankende)
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/gfp.h>
9 #include <linux/types.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/dma-mapping.h>
15 
16 #include <asm/irq.h>
17 #include <asm/io.h>
18 #include <asm/dma.h>
19 
20 #include <asm/jazz.h>
21 #include <asm/jazzdma.h>
22 
23 #include <scsi/scsi_host.h>
24 
25 #include "esp_scsi.h"
26 
27 #define DRV_MODULE_NAME		"jazz_esp"
28 #define PFX DRV_MODULE_NAME	": "
29 #define DRV_VERSION		"1.000"
30 #define DRV_MODULE_RELDATE	"May 19, 2007"
31 
32 static void jazz_esp_write8(struct esp *esp, u8 val, unsigned long reg)
33 {
34 	*(volatile u8 *)(esp->regs + reg) = val;
35 }
36 
37 static u8 jazz_esp_read8(struct esp *esp, unsigned long reg)
38 {
39 	return *(volatile u8 *)(esp->regs + reg);
40 }
41 
42 static int jazz_esp_irq_pending(struct esp *esp)
43 {
44 	if (jazz_esp_read8(esp, ESP_STATUS) & ESP_STAT_INTR)
45 		return 1;
46 	return 0;
47 }
48 
49 static void jazz_esp_reset_dma(struct esp *esp)
50 {
51 	vdma_disable ((int)esp->dma_regs);
52 }
53 
54 static void jazz_esp_dma_drain(struct esp *esp)
55 {
56 	/* nothing to do */
57 }
58 
59 static void jazz_esp_dma_invalidate(struct esp *esp)
60 {
61 	vdma_disable ((int)esp->dma_regs);
62 }
63 
64 static void jazz_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count,
65 				  u32 dma_count, int write, u8 cmd)
66 {
67 	BUG_ON(!(cmd & ESP_CMD_DMA));
68 
69 	jazz_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW);
70 	jazz_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED);
71 	vdma_disable ((int)esp->dma_regs);
72 	if (write)
73 		vdma_set_mode ((int)esp->dma_regs, DMA_MODE_READ);
74 	else
75 		vdma_set_mode ((int)esp->dma_regs, DMA_MODE_WRITE);
76 
77 	vdma_set_addr ((int)esp->dma_regs, addr);
78 	vdma_set_count ((int)esp->dma_regs, dma_count);
79 	vdma_enable ((int)esp->dma_regs);
80 
81 	scsi_esp_cmd(esp, cmd);
82 }
83 
84 static int jazz_esp_dma_error(struct esp *esp)
85 {
86 	u32 enable = vdma_get_enable((int)esp->dma_regs);
87 
88 	if (enable & (R4030_MEM_INTR|R4030_ADDR_INTR))
89 		return 1;
90 
91 	return 0;
92 }
93 
94 static const struct esp_driver_ops jazz_esp_ops = {
95 	.esp_write8	=	jazz_esp_write8,
96 	.esp_read8	=	jazz_esp_read8,
97 	.irq_pending	=	jazz_esp_irq_pending,
98 	.reset_dma	=	jazz_esp_reset_dma,
99 	.dma_drain	=	jazz_esp_dma_drain,
100 	.dma_invalidate	=	jazz_esp_dma_invalidate,
101 	.send_dma_cmd	=	jazz_esp_send_dma_cmd,
102 	.dma_error	=	jazz_esp_dma_error,
103 };
104 
105 static int esp_jazz_probe(struct platform_device *dev)
106 {
107 	const struct scsi_host_template *tpnt = &scsi_esp_template;
108 	struct Scsi_Host *host;
109 	struct esp *esp;
110 	struct resource *res;
111 	int err;
112 
113 	host = scsi_host_alloc(tpnt, sizeof(struct esp));
114 
115 	err = -ENOMEM;
116 	if (!host)
117 		goto fail;
118 
119 	host->max_id = 8;
120 	esp = shost_priv(host);
121 
122 	esp->host = host;
123 	esp->dev = &dev->dev;
124 	esp->ops = &jazz_esp_ops;
125 
126 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
127 	if (!res)
128 		goto fail_unlink;
129 
130 	esp->regs = (void __iomem *)res->start;
131 	if (!esp->regs)
132 		goto fail_unlink;
133 
134 	res = platform_get_resource(dev, IORESOURCE_MEM, 1);
135 	if (!res)
136 		goto fail_unlink;
137 
138 	esp->dma_regs = (void __iomem *)res->start;
139 
140 	esp->command_block = dma_alloc_coherent(esp->dev, 16,
141 						&esp->command_block_dma,
142 						GFP_KERNEL);
143 	if (!esp->command_block)
144 		goto fail_unmap_regs;
145 
146 	host->irq = err = platform_get_irq(dev, 0);
147 	if (err < 0)
148 		goto fail_unmap_command_block;
149 	err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, "ESP", esp);
150 	if (err < 0)
151 		goto fail_unmap_command_block;
152 
153 	esp->scsi_id = 7;
154 	esp->host->this_id = esp->scsi_id;
155 	esp->scsi_id_mask = (1 << esp->scsi_id);
156 	esp->cfreq = 40000000;
157 
158 	dev_set_drvdata(&dev->dev, esp);
159 
160 	err = scsi_esp_register(esp);
161 	if (err)
162 		goto fail_free_irq;
163 
164 	return 0;
165 
166 fail_free_irq:
167 	free_irq(host->irq, esp);
168 fail_unmap_command_block:
169 	dma_free_coherent(esp->dev, 16,
170 			  esp->command_block,
171 			  esp->command_block_dma);
172 fail_unmap_regs:
173 fail_unlink:
174 	scsi_host_put(host);
175 fail:
176 	return err;
177 }
178 
179 static int esp_jazz_remove(struct platform_device *dev)
180 {
181 	struct esp *esp = dev_get_drvdata(&dev->dev);
182 	unsigned int irq = esp->host->irq;
183 
184 	scsi_esp_unregister(esp);
185 
186 	free_irq(irq, esp);
187 	dma_free_coherent(esp->dev, 16,
188 			  esp->command_block,
189 			  esp->command_block_dma);
190 
191 	scsi_host_put(esp->host);
192 
193 	return 0;
194 }
195 
196 /* work with hotplug and coldplug */
197 MODULE_ALIAS("platform:jazz_esp");
198 
199 static struct platform_driver esp_jazz_driver = {
200 	.probe		= esp_jazz_probe,
201 	.remove		= esp_jazz_remove,
202 	.driver	= {
203 		.name	= "jazz_esp",
204 	},
205 };
206 module_platform_driver(esp_jazz_driver);
207 
208 MODULE_DESCRIPTION("JAZZ ESP SCSI driver");
209 MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)");
210 MODULE_LICENSE("GPL");
211 MODULE_VERSION(DRV_VERSION);
212