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6
7#include <common.h>
8#include <dm.h>
9#include <errno.h>
10#include <serial.h>
11#include <asm/io.h>
12#include <linux/bitops.h>
13
14
15#define ALTERA_JTAG_RVALID BIT(15)
16
17
18#define ALTERA_JTAG_AC BIT(10)
19#define ALTERA_JTAG_RRDY BIT(12)
20#define ALTERA_JTAG_WSPACE(d) ((d) >> 16)
21
22#define ALTERA_JTAG_WRITE_DEPTH 64
23
24struct altera_jtaguart_regs {
25 u32 data;
26 u32 control;
27};
28
29struct altera_jtaguart_plat {
30 struct altera_jtaguart_regs *regs;
31};
32
33static int altera_jtaguart_setbrg(struct udevice *dev, int baudrate)
34{
35 return 0;
36}
37
38static int altera_jtaguart_putc(struct udevice *dev, const char ch)
39{
40 struct altera_jtaguart_plat *plat = dev_get_plat(dev);
41 struct altera_jtaguart_regs *const regs = plat->regs;
42 u32 st = readl(®s->control);
43
44#ifdef CONFIG_ALTERA_JTAG_UART_BYPASS
45 if (!(st & ALTERA_JTAG_AC))
46 return -ENETUNREACH;
47#endif
48
49 if (ALTERA_JTAG_WSPACE(st) == 0)
50 return -EAGAIN;
51
52 writel(ch, ®s->data);
53
54 return 0;
55}
56
57static int altera_jtaguart_pending(struct udevice *dev, bool input)
58{
59 struct altera_jtaguart_plat *plat = dev_get_plat(dev);
60 struct altera_jtaguart_regs *const regs = plat->regs;
61 u32 st = readl(®s->control);
62
63 if (input)
64 return st & ALTERA_JTAG_RRDY ? 1 : 0;
65 else
66 return !(ALTERA_JTAG_WSPACE(st) == ALTERA_JTAG_WRITE_DEPTH);
67}
68
69static int altera_jtaguart_getc(struct udevice *dev)
70{
71 struct altera_jtaguart_plat *plat = dev_get_plat(dev);
72 struct altera_jtaguart_regs *const regs = plat->regs;
73 u32 val;
74
75 val = readl(®s->data);
76
77 if (!(val & ALTERA_JTAG_RVALID))
78 return -EAGAIN;
79
80 return val & 0xff;
81}
82
83static int altera_jtaguart_probe(struct udevice *dev)
84{
85#ifdef CONFIG_ALTERA_JTAG_UART_BYPASS
86 struct altera_jtaguart_plat *plat = dev_get_plat(dev);
87 struct altera_jtaguart_regs *const regs = plat->regs;
88
89 writel(ALTERA_JTAG_AC, ®s->control);
90#endif
91 return 0;
92}
93
94static int altera_jtaguart_of_to_plat(struct udevice *dev)
95{
96 struct altera_jtaguart_plat *plat = dev_get_plat(dev);
97
98 plat->regs = map_physmem(dev_read_addr(dev),
99 sizeof(struct altera_jtaguart_regs),
100 MAP_NOCACHE);
101
102 return 0;
103}
104
105static const struct dm_serial_ops altera_jtaguart_ops = {
106 .putc = altera_jtaguart_putc,
107 .pending = altera_jtaguart_pending,
108 .getc = altera_jtaguart_getc,
109 .setbrg = altera_jtaguart_setbrg,
110};
111
112static const struct udevice_id altera_jtaguart_ids[] = {
113 { .compatible = "altr,juart-1.0" },
114 {}
115};
116
117U_BOOT_DRIVER(altera_jtaguart) = {
118 .name = "altera_jtaguart",
119 .id = UCLASS_SERIAL,
120 .of_match = altera_jtaguart_ids,
121 .of_to_plat = altera_jtaguart_of_to_plat,
122 .plat_auto = sizeof(struct altera_jtaguart_plat),
123 .probe = altera_jtaguart_probe,
124 .ops = &altera_jtaguart_ops,
125};
126
127#ifdef CONFIG_DEBUG_UART_ALTERA_JTAGUART
128
129#include <debug_uart.h>
130
131static inline void _debug_uart_init(void)
132{
133}
134
135static inline void _debug_uart_putc(int ch)
136{
137 struct altera_jtaguart_regs *regs = (void *)CONFIG_DEBUG_UART_BASE;
138
139 while (1) {
140 u32 st = readl(®s->control);
141
142 if (ALTERA_JTAG_WSPACE(st))
143 break;
144 }
145
146 writel(ch, ®s->data);
147}
148
149DEBUG_UART_FUNCS
150
151#endif
152