xref: /openbmc/qemu/hw/block/tc58128.c (revision ddbb0d09)
1 #include "hw/hw.h"
2 #include "hw/sh4/sh.h"
3 #include "hw/loader.h"
4 #include "sysemu/qtest.h"
5 #include "qemu/error-report.h"
6 
7 #define CE1  0x0100
8 #define CE2  0x0200
9 #define RE   0x0400
10 #define WE   0x0800
11 #define ALE  0x1000
12 #define CLE  0x2000
13 #define RDY1 0x4000
14 #define RDY2 0x8000
15 #define RDY(n) ((n) == 0 ? RDY1 : RDY2)
16 
17 typedef enum { WAIT, READ1, READ2, READ3 } state_t;
18 
19 typedef struct {
20     uint8_t *flash_contents;
21     state_t state;
22     uint32_t address;
23     uint8_t address_cycle;
24 } tc58128_dev;
25 
26 static tc58128_dev tc58128_devs[2];
27 
28 #define FLASH_SIZE (16*1024*1024)
29 
30 static void init_dev(tc58128_dev * dev, const char *filename)
31 {
32     int ret, blocks;
33 
34     dev->state = WAIT;
35     dev->flash_contents = g_malloc(FLASH_SIZE);
36     memset(dev->flash_contents, 0xff, FLASH_SIZE);
37     if (filename) {
38 	/* Load flash image skipping the first block */
39 	ret = load_image(filename, dev->flash_contents + 528 * 32);
40 	if (ret < 0) {
41             if (!qtest_enabled()) {
42                 error_report("Could not load flash image %s", filename);
43                 exit(1);
44             }
45 	} else {
46 	    /* Build first block with number of blocks */
47 	    blocks = (ret + 528 * 32 - 1) / (528 * 32);
48 	    dev->flash_contents[0] = blocks & 0xff;
49 	    dev->flash_contents[1] = (blocks >> 8) & 0xff;
50 	    dev->flash_contents[2] = (blocks >> 16) & 0xff;
51 	    dev->flash_contents[3] = (blocks >> 24) & 0xff;
52 	    fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
53 		    filename);
54 	}
55     }
56 }
57 
58 static void handle_command(tc58128_dev * dev, uint8_t command)
59 {
60     switch (command) {
61     case 0xff:
62 	fprintf(stderr, "reset flash device\n");
63 	dev->state = WAIT;
64 	break;
65     case 0x00:
66 	fprintf(stderr, "read mode 1\n");
67 	dev->state = READ1;
68 	dev->address_cycle = 0;
69 	break;
70     case 0x01:
71 	fprintf(stderr, "read mode 2\n");
72 	dev->state = READ2;
73 	dev->address_cycle = 0;
74 	break;
75     case 0x50:
76 	fprintf(stderr, "read mode 3\n");
77 	dev->state = READ3;
78 	dev->address_cycle = 0;
79 	break;
80     default:
81 	fprintf(stderr, "unknown flash command 0x%02x\n", command);
82         abort();
83     }
84 }
85 
86 static void handle_address(tc58128_dev * dev, uint8_t data)
87 {
88     switch (dev->state) {
89     case READ1:
90     case READ2:
91     case READ3:
92 	switch (dev->address_cycle) {
93 	case 0:
94 	    dev->address = data;
95 	    if (dev->state == READ2)
96 		dev->address |= 0x100;
97 	    else if (dev->state == READ3)
98 		dev->address |= 0x200;
99 	    break;
100 	case 1:
101 	    dev->address += data * 528 * 0x100;
102 	    break;
103 	case 2:
104 	    dev->address += data * 528;
105 	    fprintf(stderr, "address pointer in flash: 0x%08x\n",
106 		    dev->address);
107 	    break;
108 	default:
109 	    /* Invalid data */
110             abort();
111 	}
112 	dev->address_cycle++;
113 	break;
114     default:
115         abort();
116     }
117 }
118 
119 static uint8_t handle_read(tc58128_dev * dev)
120 {
121 #if 0
122     if (dev->address % 0x100000 == 0)
123 	fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
124 #endif
125     return dev->flash_contents[dev->address++];
126 }
127 
128 /* We never mark the device as busy, so interrupts cannot be triggered
129    XXXXX */
130 
131 static int tc58128_cb(uint16_t porta, uint16_t portb,
132                       uint16_t * periph_pdtra, uint16_t * periph_portadir,
133                       uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
134 {
135     int dev;
136 
137     if ((porta & CE1) == 0)
138 	dev = 0;
139     else if ((porta & CE2) == 0)
140 	dev = 1;
141     else
142 	return 0;		/* No device selected */
143 
144     if ((porta & RE) && (porta & WE)) {
145 	/* Nothing to do, assert ready and return to input state */
146 	*periph_portadir &= 0xff00;
147 	*periph_portadir |= RDY(dev);
148 	*periph_pdtra |= RDY(dev);
149 	return 1;
150     }
151 
152     if (porta & CLE) {
153 	/* Command */
154 	assert((porta & WE) == 0);
155 	handle_command(&tc58128_devs[dev], porta & 0x00ff);
156     } else if (porta & ALE) {
157 	assert((porta & WE) == 0);
158 	handle_address(&tc58128_devs[dev], porta & 0x00ff);
159     } else if ((porta & RE) == 0) {
160 	*periph_portadir |= 0x00ff;
161 	*periph_pdtra &= 0xff00;
162 	*periph_pdtra |= handle_read(&tc58128_devs[dev]);
163     } else {
164         abort();
165     }
166     return 1;
167 }
168 
169 static sh7750_io_device tc58128 = {
170     RE | WE,			/* Port A triggers */
171     0,				/* Port B triggers */
172     tc58128_cb			/* Callback */
173 };
174 
175 int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
176 {
177     init_dev(&tc58128_devs[0], zone1);
178     init_dev(&tc58128_devs[1], zone2);
179     return sh7750_register_io_device(s, &tc58128);
180 }
181