1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * arch/powerpc/boot/ugecon.c |
4 | * |
5 | * USB Gecko bootwrapper console. |
6 | * Copyright (C) 2008-2009 The GameCube Linux Team |
7 | * Copyright (C) 2008,2009 Albert Herranz |
8 | */ |
9 | |
10 | #include <stddef.h> |
11 | #include "stdio.h" |
12 | #include "types.h" |
13 | #include "io.h" |
14 | #include "ops.h" |
15 | |
16 | |
17 | #define EXI_CLK_32MHZ 5 |
18 | |
19 | #define EXI_CSR 0x00 |
20 | #define EXI_CSR_CLKMASK (0x7<<4) |
21 | #define EXI_CSR_CLK_32MHZ (EXI_CLK_32MHZ<<4) |
22 | #define EXI_CSR_CSMASK (0x7<<7) |
23 | #define EXI_CSR_CS_0 (0x1<<7) /* Chip Select 001 */ |
24 | |
25 | #define EXI_CR 0x0c |
26 | #define EXI_CR_TSTART (1<<0) |
27 | #define EXI_CR_WRITE (1<<2) |
28 | #define EXI_CR_READ_WRITE (2<<2) |
29 | #define EXI_CR_TLEN(len) (((len)-1)<<4) |
30 | |
31 | #define EXI_DATA 0x10 |
32 | |
33 | |
34 | /* virtual address base for input/output, retrieved from device tree */ |
35 | static void *ug_io_base; |
36 | |
37 | |
38 | static u32 ug_io_transaction(u32 in) |
39 | { |
40 | u32 *csr_reg = ug_io_base + EXI_CSR; |
41 | u32 *data_reg = ug_io_base + EXI_DATA; |
42 | u32 *cr_reg = ug_io_base + EXI_CR; |
43 | u32 csr, data, cr; |
44 | |
45 | /* select */ |
46 | csr = EXI_CSR_CLK_32MHZ | EXI_CSR_CS_0; |
47 | out_be32(addr: csr_reg, val: csr); |
48 | |
49 | /* read/write */ |
50 | data = in; |
51 | out_be32(addr: data_reg, val: data); |
52 | cr = EXI_CR_TLEN(2) | EXI_CR_READ_WRITE | EXI_CR_TSTART; |
53 | out_be32(addr: cr_reg, val: cr); |
54 | |
55 | while (in_be32(addr: cr_reg) & EXI_CR_TSTART) |
56 | barrier(); |
57 | |
58 | /* deselect */ |
59 | out_be32(addr: csr_reg, val: 0); |
60 | |
61 | data = in_be32(addr: data_reg); |
62 | return data; |
63 | } |
64 | |
65 | static int ug_is_txfifo_ready(void) |
66 | { |
67 | return ug_io_transaction(in: 0xc0000000) & 0x04000000; |
68 | } |
69 | |
70 | static void ug_raw_putc(char ch) |
71 | { |
72 | ug_io_transaction(in: 0xb0000000 | (ch << 20)); |
73 | } |
74 | |
75 | static void ug_putc(char ch) |
76 | { |
77 | int count = 16; |
78 | |
79 | if (!ug_io_base) |
80 | return; |
81 | |
82 | while (!ug_is_txfifo_ready() && count--) |
83 | barrier(); |
84 | if (count >= 0) |
85 | ug_raw_putc(ch); |
86 | } |
87 | |
88 | void ug_console_write(const char *buf, int len) |
89 | { |
90 | char *b = (char *)buf; |
91 | |
92 | while (len--) { |
93 | if (*b == '\n') |
94 | ug_putc(ch: '\r'); |
95 | ug_putc(ch: *b++); |
96 | } |
97 | } |
98 | |
99 | static int ug_is_adapter_present(void) |
100 | { |
101 | if (!ug_io_base) |
102 | return 0; |
103 | return ug_io_transaction(in: 0x90000000) == 0x04700000; |
104 | } |
105 | |
106 | static void *ug_grab_exi_io_base(void) |
107 | { |
108 | u32 v; |
109 | void *devp; |
110 | |
111 | devp = find_node_by_compatible(prev: NULL, compat: "nintendo,flipper-exi" ); |
112 | if (devp == NULL) |
113 | goto err_out; |
114 | if (getprop(devp, name: "virtual-reg" , buf: &v, buflen: sizeof(v)) != sizeof(v)) |
115 | goto err_out; |
116 | |
117 | return (void *)v; |
118 | |
119 | err_out: |
120 | return NULL; |
121 | } |
122 | |
123 | void *ug_probe(void) |
124 | { |
125 | void *exi_io_base; |
126 | int i; |
127 | |
128 | exi_io_base = ug_grab_exi_io_base(); |
129 | if (!exi_io_base) |
130 | return NULL; |
131 | |
132 | /* look for a usbgecko on memcard slots A and B */ |
133 | for (i = 0; i < 2; i++) { |
134 | ug_io_base = exi_io_base + 0x14 * i; |
135 | if (ug_is_adapter_present()) |
136 | break; |
137 | } |
138 | if (i == 2) |
139 | ug_io_base = NULL; |
140 | return ug_io_base; |
141 | } |
142 | |
143 | |