1 /*
2 * Xilinx UARTLITE bootloader driver
3 *
4 * Copyright (C) 2007 Secret Lab Technologies Ltd.
5 *
6 * This file is licensed under the terms of the GNU General Public License
7 * version 2. This program is licensed "as is" without any warranty of any
8 * kind, whether express or implied.
9 */
10
11 #include <stdarg.h>
12 #include <stddef.h>
13 #include "types.h"
14 #include "string.h"
15 #include "stdio.h"
16 #include "io.h"
17 #include "ops.h"
18
19 #define ULITE_RX 0x00
20 #define ULITE_TX 0x04
21 #define ULITE_STATUS 0x08
22 #define ULITE_CONTROL 0x0c
23
24 #define ULITE_STATUS_RXVALID 0x01
25 #define ULITE_STATUS_TXFULL 0x08
26
27 #define ULITE_CONTROL_RST_RX 0x02
28
29 static void * reg_base;
30
uartlite_open(void)31 static int uartlite_open(void)
32 {
33 /* Clear the RX FIFO */
34 out_be32(reg_base + ULITE_CONTROL, ULITE_CONTROL_RST_RX);
35 return 0;
36 }
37
uartlite_putc(unsigned char c)38 static void uartlite_putc(unsigned char c)
39 {
40 u32 reg = ULITE_STATUS_TXFULL;
41 while (reg & ULITE_STATUS_TXFULL) /* spin on TXFULL bit */
42 reg = in_be32(reg_base + ULITE_STATUS);
43 out_be32(reg_base + ULITE_TX, c);
44 }
45
uartlite_getc(void)46 static unsigned char uartlite_getc(void)
47 {
48 u32 reg = 0;
49 while (!(reg & ULITE_STATUS_RXVALID)) /* spin waiting for RXVALID bit */
50 reg = in_be32(reg_base + ULITE_STATUS);
51 return in_be32(reg_base + ULITE_RX);
52 }
53
uartlite_tstc(void)54 static u8 uartlite_tstc(void)
55 {
56 u32 reg = in_be32(reg_base + ULITE_STATUS);
57 return reg & ULITE_STATUS_RXVALID;
58 }
59
uartlite_console_init(void * devp,struct serial_console_data * scdp)60 int uartlite_console_init(void *devp, struct serial_console_data *scdp)
61 {
62 int n;
63 unsigned long reg_phys;
64
65 n = getprop(devp, "virtual-reg", ®_base, sizeof(reg_base));
66 if (n != sizeof(reg_base)) {
67 if (!dt_xlate_reg(devp, 0, ®_phys, NULL))
68 return -1;
69
70 reg_base = (void *)reg_phys;
71 }
72
73 scdp->open = uartlite_open;
74 scdp->putc = uartlite_putc;
75 scdp->getc = uartlite_getc;
76 scdp->tstc = uartlite_tstc;
77 scdp->close = NULL;
78 return 0;
79 }
80