xref: /openbmc/qemu/hw/block/tc58128.c (revision d36f7de8)
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(filename, dev->flash_contents + 528 * 32);
42 	if (ret < 0) {
43             if (!qtest_enabled()) {
44                 error_report("Could not load flash image %s", filename);
45                 exit(1);
46             }
47 	} else {
48 	    /* Build first block with number of blocks */
49             blocks = DIV_ROUND_UP(ret, 528 * 32);
50 	    dev->flash_contents[0] = blocks & 0xff;
51 	    dev->flash_contents[1] = (blocks >> 8) & 0xff;
52 	    dev->flash_contents[2] = (blocks >> 16) & 0xff;
53 	    dev->flash_contents[3] = (blocks >> 24) & 0xff;
54 	    fprintf(stderr, "loaded %d bytes for %s into flash\n", ret,
55 		    filename);
56 	}
57     }
58 }
59 
60 static void handle_command(tc58128_dev * dev, uint8_t command)
61 {
62     switch (command) {
63     case 0xff:
64 	fprintf(stderr, "reset flash device\n");
65 	dev->state = WAIT;
66 	break;
67     case 0x00:
68 	fprintf(stderr, "read mode 1\n");
69 	dev->state = READ1;
70 	dev->address_cycle = 0;
71 	break;
72     case 0x01:
73 	fprintf(stderr, "read mode 2\n");
74 	dev->state = READ2;
75 	dev->address_cycle = 0;
76 	break;
77     case 0x50:
78 	fprintf(stderr, "read mode 3\n");
79 	dev->state = READ3;
80 	dev->address_cycle = 0;
81 	break;
82     default:
83 	fprintf(stderr, "unknown flash command 0x%02x\n", command);
84         abort();
85     }
86 }
87 
88 static void handle_address(tc58128_dev * dev, uint8_t data)
89 {
90     switch (dev->state) {
91     case READ1:
92     case READ2:
93     case READ3:
94 	switch (dev->address_cycle) {
95 	case 0:
96 	    dev->address = data;
97 	    if (dev->state == READ2)
98 		dev->address |= 0x100;
99 	    else if (dev->state == READ3)
100 		dev->address |= 0x200;
101 	    break;
102 	case 1:
103 	    dev->address += data * 528 * 0x100;
104 	    break;
105 	case 2:
106 	    dev->address += data * 528;
107 	    fprintf(stderr, "address pointer in flash: 0x%08x\n",
108 		    dev->address);
109 	    break;
110 	default:
111 	    /* Invalid data */
112             abort();
113 	}
114 	dev->address_cycle++;
115 	break;
116     default:
117         abort();
118     }
119 }
120 
121 static uint8_t handle_read(tc58128_dev * dev)
122 {
123 #if 0
124     if (dev->address % 0x100000 == 0)
125 	fprintf(stderr, "reading flash at address 0x%08x\n", dev->address);
126 #endif
127     return dev->flash_contents[dev->address++];
128 }
129 
130 /* We never mark the device as busy, so interrupts cannot be triggered
131    XXXXX */
132 
133 static int tc58128_cb(uint16_t porta, uint16_t portb,
134                       uint16_t * periph_pdtra, uint16_t * periph_portadir,
135                       uint16_t * periph_pdtrb, uint16_t * periph_portbdir)
136 {
137     int dev;
138 
139     if ((porta & CE1) == 0)
140 	dev = 0;
141     else if ((porta & CE2) == 0)
142 	dev = 1;
143     else
144 	return 0;		/* No device selected */
145 
146     if ((porta & RE) && (porta & WE)) {
147 	/* Nothing to do, assert ready and return to input state */
148 	*periph_portadir &= 0xff00;
149 	*periph_portadir |= RDY(dev);
150 	*periph_pdtra |= RDY(dev);
151 	return 1;
152     }
153 
154     if (porta & CLE) {
155 	/* Command */
156 	assert((porta & WE) == 0);
157 	handle_command(&tc58128_devs[dev], porta & 0x00ff);
158     } else if (porta & ALE) {
159 	assert((porta & WE) == 0);
160 	handle_address(&tc58128_devs[dev], porta & 0x00ff);
161     } else if ((porta & RE) == 0) {
162 	*periph_portadir |= 0x00ff;
163 	*periph_pdtra &= 0xff00;
164 	*periph_pdtra |= handle_read(&tc58128_devs[dev]);
165     } else {
166         abort();
167     }
168     return 1;
169 }
170 
171 static sh7750_io_device tc58128 = {
172     RE | WE,			/* Port A triggers */
173     0,				/* Port B triggers */
174     tc58128_cb			/* Callback */
175 };
176 
177 int tc58128_init(struct SH7750State *s, const char *zone1, const char *zone2)
178 {
179     init_dev(&tc58128_devs[0], zone1);
180     init_dev(&tc58128_devs[1], zone2);
181     return sh7750_register_io_device(s, &tc58128);
182 }
183