2 * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
3 * Scott McNutt <smcnutt@psyent.com>
5 * SPDX-License-Identifier: GPL-2.0+
12 #include <linux/compiler.h>
15 struct altera_jtaguart_regs
{
16 u32 data
; /* Data register */
17 u32 control
; /* Control register */
20 struct altera_jtaguart_platdata
{
21 struct altera_jtaguart_regs
*regs
;
25 #define ALTERA_JTAG_RVALID (1<<15) /* Read valid */
27 /* control register */
28 #define ALTERA_JTAG_AC (1 << 10) /* activity indicator */
29 #define ALTERA_JTAG_RRDY (1 << 12) /* read available */
30 #define ALTERA_JTAG_WSPACE(d) ((d)>>16) /* Write space avail */
31 /* Write fifo size. FIXME: this should be extracted with sopc2dts */
32 #define ALTERA_JTAG_WRITE_DEPTH 64
34 DECLARE_GLOBAL_DATA_PTR
;
36 static int altera_jtaguart_setbrg(struct udevice
*dev
, int baudrate
)
41 static int altera_jtaguart_putc(struct udevice
*dev
, const char ch
)
43 struct altera_jtaguart_platdata
*plat
= dev
->platdata
;
44 struct altera_jtaguart_regs
*const regs
= plat
->regs
;
45 u32 st
= readl(®s
->control
);
47 #ifdef CONFIG_ALTERA_JTAG_UART_BYPASS
48 if (!(st
& ALTERA_JTAG_AC
)) /* no connection yet */
52 if (ALTERA_JTAG_WSPACE(st
) == 0)
55 writel(ch
, ®s
->data
);
60 static int altera_jtaguart_pending(struct udevice
*dev
, bool input
)
62 struct altera_jtaguart_platdata
*plat
= dev
->platdata
;
63 struct altera_jtaguart_regs
*const regs
= plat
->regs
;
64 u32 st
= readl(®s
->control
);
67 return st
& ALTERA_JTAG_RRDY
? 1 : 0;
69 return !(ALTERA_JTAG_WSPACE(st
) == ALTERA_JTAG_WRITE_DEPTH
);
72 static int altera_jtaguart_getc(struct udevice
*dev
)
74 struct altera_jtaguart_platdata
*plat
= dev
->platdata
;
75 struct altera_jtaguart_regs
*const regs
= plat
->regs
;
78 val
= readl(®s
->data
);
80 if (!(val
& ALTERA_JTAG_RVALID
))
86 static int altera_jtaguart_probe(struct udevice
*dev
)
88 #ifdef CONFIG_ALTERA_JTAG_UART_BYPASS
89 struct altera_jtaguart_platdata
*plat
= dev
->platdata
;
90 struct altera_jtaguart_regs
*const regs
= plat
->regs
;
92 writel(ALTERA_JTAG_AC
, ®s
->control
); /* clear AC flag */
97 static int altera_jtaguart_ofdata_to_platdata(struct udevice
*dev
)
99 struct altera_jtaguart_platdata
*plat
= dev_get_platdata(dev
);
101 plat
->regs
= ioremap(dev_get_addr(dev
),
102 sizeof(struct altera_jtaguart_regs
));
107 static const struct dm_serial_ops altera_jtaguart_ops
= {
108 .putc
= altera_jtaguart_putc
,
109 .pending
= altera_jtaguart_pending
,
110 .getc
= altera_jtaguart_getc
,
111 .setbrg
= altera_jtaguart_setbrg
,
114 static const struct udevice_id altera_jtaguart_ids
[] = {
115 { .compatible
= "altr,juart-1.0", },
119 U_BOOT_DRIVER(altera_jtaguart
) = {
120 .name
= "altera_jtaguart",
122 .of_match
= altera_jtaguart_ids
,
123 .ofdata_to_platdata
= altera_jtaguart_ofdata_to_platdata
,
124 .platdata_auto_alloc_size
= sizeof(struct altera_jtaguart_platdata
),
125 .probe
= altera_jtaguart_probe
,
126 .ops
= &altera_jtaguart_ops
,
127 .flags
= DM_FLAG_PRE_RELOC
,
130 #ifdef CONFIG_DEBUG_UART_ALTERA_JTAGUART
132 #include <debug_uart.h>
134 void debug_uart_init(void)
138 static inline void _debug_uart_putc(int ch
)
140 struct altera_jtaguart_regs
*regs
= (void *)CONFIG_DEBUG_UART_BASE
;
143 u32 st
= readl(®s
->control
);
145 if (ALTERA_JTAG_WSPACE(st
))
149 writel(ch
, ®s
->data
);