xref: /openbmc/qemu/hw/block/tc58128.c (revision da054c64)
1 #include "qemu/osdep.h"
2 #include "qemu/units.h"
3 #include "hw/hw.h"
4 #include "hw/sh4/sh.h"
5 #include "hw/loader.h"
6 #include "sysemu/qtest.h"
7 #include "qemu/error-report.h"
8 
9 #define CE1  0x0100
10 #define CE2  0x0200
11 #define RE   0x0400
12 #define WE   0x0800
13 #define ALE  0x1000
14 #define CLE  0x2000
15 #define RDY1 0x4000
16 #define RDY2 0x8000
17 #define RDY(n) ((n) == 0 ? RDY1 : RDY2)
18 
19 typedef enum { WAIT, READ1, READ2, READ3 } state_t;
20 
21 typedef struct {
22     uint8_t *flash_contents;
23     state_t state;
24     uint32_t address;
25     uint8_t address_cycle;
26 } tc58128_dev;
27 
28 static tc58128_dev tc58128_devs[2];
29 
30 #define FLASH_SIZE (16 * MiB)
31 
32 static void init_dev(tc58128_dev * dev, const char *filename)
33 {
34     int ret, blocks;
35 
36     dev->state = WAIT;
37     dev->flash_contents = g_malloc(FLASH_SIZE);
38     memset(dev->flash_contents, 0xff, FLASH_SIZE);
39     if (filename) {
40 	/* Load flash image skipping the first block */
41         ret = load_image_size(filename, dev->flash_contents + 528 * 32,
42                               FLASH_SIZE - 528 * 32);
43 	if (ret < 0) {
44             if (!qtest_enabled()) {
45                 error_report("Could not load flash image %s", filename);
46                 exit(1);
47             }
48 	} else {
49 	    /* Build first block with number of blocks */
50             blocks = DIV_ROUND_UP(ret, 528 * 32);
51 	    dev->flash_contents[0] = blocks & 0xff;
52 	    dev->flash_contents[1] = (blocks >> 8) & 0xff;
53 	    dev->flash_contents[2] = (blocks >> 16) & 0xff;
54 	    dev->flash_contents[3] = (blocks >> 24) & 0xff;
55 	    fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
56 		    filename);
57 	}
58     }
59 }
60 
61 static void handle_command(tc58128_dev * dev, uint8_t command)
62 {
63     switch (command) {
64     case 0xff:
65 	fprintf(stderr, "reset flash device\n");
66 	dev->state = WAIT;
67 	break;
68     case 0x00:
69 	fprintf(stderr, "read mode 1\n");
70 	dev->state = READ1;
71 	dev->address_cycle = 0;
72 	break;
73     case 0x01:
74 	fprintf(stderr, "read mode 2\n");
75 	dev->state = READ2;
76 	dev->address_cycle = 0;
77 	break;
78     case 0x50:
79 	fprintf(stderr, "read mode 3\n");
80 	dev->state = READ3;
81 	dev->address_cycle = 0;
82 	break;
83     default:
84 	fprintf(stderr, "unknown flash command 0x%02x\n", command);
85         abort();
86     }
87 }
88 
89 static void handle_address(tc58128_dev * dev, uint8_t data)
90 {
91     switch (dev->state) {
92     case READ1:
93     case READ2:
94     case READ3:
95 	switch (dev->address_cycle) {
96 	case 0:
97 	    dev->address = data;
98 	    if (dev->state == READ2)
99 		dev->address |= 0x100;
100 	    else if (dev->state == READ3)
101 		dev->address |= 0x200;
102 	    break;
103 	case 1:
104 	    dev->address += data * 528 * 0x100;
105 	    break;
106 	case 2:
107 	    dev->address += data * 528;
108 	    fprintf(stderr, "address pointer in flash: 0x%08x\n",
109 		    dev->address);
110 	    break;
111 	default:
112 	    /* Invalid data */
113             abort();
114 	}
115 	dev->address_cycle++;
116 	break;
117     default:
118         abort();
119     }
120 }
121 
122 static uint8_t handle_read(tc58128_dev * dev)
123 {
124 #if 0
125     if (dev->address % 0x100000 == 0)
126 	fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
127 #endif
128     return dev->flash_contents[dev->address++];
129 }
130 
131 /* We never mark the device as busy, so interrupts cannot be triggered
132    XXXXX */
133 
134 static int tc58128_cb(uint16_t porta, uint16_t portb,
135                       uint16_t * periph_pdtra, uint16_t * periph_portadir,
136                       uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
137 {
138     int dev;
139 
140     if ((porta & CE1) == 0)
141 	dev = 0;
142     else if ((porta & CE2) == 0)
143 	dev = 1;
144     else
145 	return 0;		/* No device selected */
146 
147     if ((porta & RE) && (porta & WE)) {
148 	/* Nothing to do, assert ready and return to input state */
149 	*periph_portadir &= 0xff00;
150 	*periph_portadir |= RDY(dev);
151 	*periph_pdtra |= RDY(dev);
152 	return 1;
153     }
154 
155     if (porta & CLE) {
156 	/* Command */
157 	assert((porta & WE) == 0);
158 	handle_command(&tc58128_devs[dev], porta & 0x00ff);
159     } else if (porta & ALE) {
160 	assert((porta & WE) == 0);
161 	handle_address(&tc58128_devs[dev], porta & 0x00ff);
162     } else if ((porta & RE) == 0) {
163 	*periph_portadir |= 0x00ff;
164 	*periph_pdtra &= 0xff00;
165 	*periph_pdtra |= handle_read(&tc58128_devs[dev]);
166     } else {
167         abort();
168     }
169     return 1;
170 }
171 
172 static sh7750_io_device tc58128 = {
173     RE | WE,			/* Port A triggers */
174     0,				/* Port B triggers */
175     tc58128_cb			/* Callback */
176 };
177 
178 int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
179 {
180     init_dev(&tc58128_devs[0], zone1);
181     init_dev(&tc58128_devs[1], zone2);
182     return sh7750_register_io_device(s, &tc58128);
183 }
184