xref: /openbmc/qemu/hw/block/tc58128.c (revision b91a0fa7)
1 /*
2  * TC58128 NAND EEPROM emulation
3  *
4  * Copyright (c) 2005 Samuel Tardieu
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  *
25  * SPDX-License-Identifier: MIT
26  */
27 #include "qemu/osdep.h"
28 #include "qemu/units.h"
29 #include "hw/sh4/sh.h"
30 #include "hw/loader.h"
31 #include "sysemu/qtest.h"
32 #include "qemu/error-report.h"
33 
34 #define CE1  0x0100
35 #define CE2  0x0200
36 #define RE   0x0400
37 #define WE   0x0800
38 #define ALE  0x1000
39 #define CLE  0x2000
40 #define RDY1 0x4000
41 #define RDY2 0x8000
42 #define RDY(n) ((n) == 0 ? RDY1 : RDY2)
43 
44 typedef enum { WAIT, READ1, READ2, READ3 } state_t;
45 
46 typedef struct {
47     uint8_t *flash_contents;
48     state_t state;
49     uint32_t address;
50     uint8_t address_cycle;
51 } tc58128_dev;
52 
53 static tc58128_dev tc58128_devs[2];
54 
55 #define FLASH_SIZE (16 * MiB)
56 
57 static void init_dev(tc58128_dev * dev, const char *filename)
58 {
59     int ret, blocks;
60 
61     dev->state = WAIT;
62     dev->flash_contents = g_malloc(FLASH_SIZE);
63     memset(dev->flash_contents, 0xff, FLASH_SIZE);
64     if (filename) {
65 	/* Load flash image skipping the first block */
66         ret = load_image_size(filename, dev->flash_contents + 528 * 32,
67                               FLASH_SIZE - 528 * 32);
68 	if (ret < 0) {
69             if (!qtest_enabled()) {
70                 error_report("Could not load flash image %s", filename);
71                 exit(1);
72             }
73 	} else {
74 	    /* Build first block with number of blocks */
75             blocks = DIV_ROUND_UP(ret, 528 * 32);
76 	    dev->flash_contents[0] = blocks & 0xff;
77 	    dev->flash_contents[1] = (blocks >> 8) & 0xff;
78 	    dev->flash_contents[2] = (blocks >> 16) & 0xff;
79 	    dev->flash_contents[3] = (blocks >> 24) & 0xff;
80 	    fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
81 		    filename);
82 	}
83     }
84 }
85 
86 static void handle_command(tc58128_dev * dev, uint8_t command)
87 {
88     switch (command) {
89     case 0xff:
90 	fprintf(stderr, "reset flash device\n");
91 	dev->state = WAIT;
92 	break;
93     case 0x00:
94 	fprintf(stderr, "read mode 1\n");
95 	dev->state = READ1;
96 	dev->address_cycle = 0;
97 	break;
98     case 0x01:
99 	fprintf(stderr, "read mode 2\n");
100 	dev->state = READ2;
101 	dev->address_cycle = 0;
102 	break;
103     case 0x50:
104 	fprintf(stderr, "read mode 3\n");
105 	dev->state = READ3;
106 	dev->address_cycle = 0;
107 	break;
108     default:
109 	fprintf(stderr, "unknown flash command 0x%02x\n", command);
110         abort();
111     }
112 }
113 
114 static void handle_address(tc58128_dev * dev, uint8_t data)
115 {
116     switch (dev->state) {
117     case READ1:
118     case READ2:
119     case READ3:
120 	switch (dev->address_cycle) {
121 	case 0:
122 	    dev->address = data;
123 	    if (dev->state == READ2)
124 		dev->address |= 0x100;
125 	    else if (dev->state == READ3)
126 		dev->address |= 0x200;
127 	    break;
128 	case 1:
129 	    dev->address += data * 528 * 0x100;
130 	    break;
131 	case 2:
132 	    dev->address += data * 528;
133 	    fprintf(stderr, "address pointer in flash: 0x%08x\n",
134 		    dev->address);
135 	    break;
136 	default:
137 	    /* Invalid data */
138             abort();
139 	}
140 	dev->address_cycle++;
141 	break;
142     default:
143         abort();
144     }
145 }
146 
147 static uint8_t handle_read(tc58128_dev * dev)
148 {
149 #if 0
150     if (dev->address % 0x100000 == 0)
151 	fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
152 #endif
153     return dev->flash_contents[dev->address++];
154 }
155 
156 /* We never mark the device as busy, so interrupts cannot be triggered
157    XXXXX */
158 
159 static int tc58128_cb(uint16_t porta, uint16_t portb,
160                       uint16_t * periph_pdtra, uint16_t * periph_portadir,
161                       uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
162 {
163     int dev;
164 
165     if ((porta & CE1) == 0)
166 	dev = 0;
167     else if ((porta & CE2) == 0)
168 	dev = 1;
169     else
170 	return 0;		/* No device selected */
171 
172     if ((porta & RE) && (porta & WE)) {
173 	/* Nothing to do, assert ready and return to input state */
174 	*periph_portadir &= 0xff00;
175 	*periph_portadir |= RDY(dev);
176 	*periph_pdtra |= RDY(dev);
177 	return 1;
178     }
179 
180     if (porta & CLE) {
181 	/* Command */
182 	assert((porta & WE) == 0);
183 	handle_command(&tc58128_devs[dev], porta & 0x00ff);
184     } else if (porta & ALE) {
185 	assert((porta & WE) == 0);
186 	handle_address(&tc58128_devs[dev], porta & 0x00ff);
187     } else if ((porta & RE) == 0) {
188 	*periph_portadir |= 0x00ff;
189 	*periph_pdtra &= 0xff00;
190 	*periph_pdtra |= handle_read(&tc58128_devs[dev]);
191     } else {
192         abort();
193     }
194     return 1;
195 }
196 
197 static sh7750_io_device tc58128 = {
198     RE | WE,			/* Port A triggers */
199     0,				/* Port B triggers */
200     tc58128_cb			/* Callback */
201 };
202 
203 int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
204 {
205     init_dev(&tc58128_devs[0], zone1);
206     init_dev(&tc58128_devs[1], zone2);
207     return sh7750_register_io_device(s, &tc58128);
208 }
209