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 BIT(15) /* Read valid */
27 /* control register */
28 #define ALTERA_JTAG_AC BIT(10) /* activity indicator */
29 #define ALTERA_JTAG_RRDY BIT(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);