aboutsummaryrefslogtreecommitdiffstats
path: root/package/boot/uboot-ar71xx/files/cpu/mips/ar71xx_serial.c
blob: f093318952d849118296dd9cc08e133c04c536f9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
/*
 * (C) Copyright 2010
 * Michael Kurz <michi.kurz@googlemail.com>.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <asm/addrspace.h>
#include <asm/types.h>
#include <config.h>
#include <asm/ar71xx.h>

#define		REG_SIZE		4

/* === END OF CONFIG === */

/* register offset */
#define         OFS_RCV_BUFFER          (0*REG_SIZE)
#define         OFS_TRANS_HOLD          (0*REG_SIZE)
#define         OFS_SEND_BUFFER         (0*REG_SIZE)
#define         OFS_INTR_ENABLE         (1*REG_SIZE)
#define         OFS_INTR_ID             (2*REG_SIZE)
#define         OFS_DATA_FORMAT         (3*REG_SIZE)
#define         OFS_LINE_CONTROL        (3*REG_SIZE)
#define         OFS_MODEM_CONTROL       (4*REG_SIZE)
#define         OFS_RS232_OUTPUT        (4*REG_SIZE)
#define         OFS_LINE_STATUS         (5*REG_SIZE)
#define         OFS_MODEM_STATUS        (6*REG_SIZE)
#define         OFS_RS232_INPUT         (6*REG_SIZE)
#define         OFS_SCRATCH_PAD         (7*REG_SIZE)

#define         OFS_DIVISOR_LSB         (0*REG_SIZE)
#define         OFS_DIVISOR_MSB         (1*REG_SIZE)

#define         UART16550_READ(y)   readl(KSEG1ADDR(AR71XX_UART_BASE+y))
#define         UART16550_WRITE(x, z)  writel(z, KSEG1ADDR((AR71XX_UART_BASE+x)))

void 
ar71xx_sys_frequency(u32 *cpu_freq, u32 *ddr_freq, u32 *ahb_freq)
{
#ifndef CONFIG_AR91XX
    u32 pll, pll_div, cpu_div, ahb_div, ddr_div, freq;

    pll = readl(KSEG1ADDR(AR71XX_PLL_REG_CPU_CONFIG + AR71XX_PLL_BASE));

    pll_div = 
        ((pll & AR71XX_PLL_DIV_MASK) >> AR71XX_PLL_DIV_SHIFT) + 1;

    cpu_div = 
        ((pll & AR71XX_CPU_DIV_MASK) >> AR71XX_CPU_DIV_SHIFT) + 1;

    ddr_div = 
        ((pll & AR71XX_DDR_DIV_MASK) >> AR71XX_DDR_DIV_SHIFT) + 1;

    ahb_div = 
       (((pll & AR71XX_AHB_DIV_MASK) >> AR71XX_AHB_DIV_SHIFT) + 1)*2;

    freq = pll_div * 40000000; 

    if (cpu_freq)
        *cpu_freq = freq/cpu_div;

    if (ddr_freq)
        *ddr_freq = freq/ddr_div;

    if (ahb_freq)
        *ahb_freq = (freq/cpu_div)/ahb_div;

#else
    u32 pll, pll_div, ahb_div, ddr_div, freq;

    pll = readl(KSEG1ADDR(AR91XX_PLL_REG_CPU_CONFIG + AR71XX_PLL_BASE));

    pll_div = 
        ((pll & AR91XX_PLL_DIV_MASK) >> AR91XX_PLL_DIV_SHIFT);

    ddr_div = 
        ((pll & AR91XX_DDR_DIV_MASK) >> AR91XX_DDR_DIV_SHIFT) + 1;

    ahb_div = 
       (((pll & AR91XX_AHB_DIV_MASK) >> AR91XX_AHB_DIV_SHIFT) + 1)*2;

    freq = pll_div * 5000000; 

    if (cpu_freq)
        *cpu_freq = freq;

    if (ddr_freq)
        *ddr_freq = freq/ddr_div;

    if (ahb_freq)
        *ahb_freq = freq/ahb_div;
#endif
}


int serial_init(void)
{
    u32 div;
    u32 ahb_freq = 100000000;

    ar71xx_sys_frequency  (0, 0, &ahb_freq);  
    div  = ahb_freq/(16 * CONFIG_BAUDRATE);  

	// enable uart pins
#ifndef CONFIG_AR91XX
    writel(AR71XX_GPIO_FUNC_UART_EN, KSEG1ADDR(AR71XX_GPIO_BASE + GPIO_REG_FUNC));
#else
	writel(AR91XX_GPIO_FUNC_UART_EN, KSEG1ADDR(AR71XX_GPIO_BASE + GPIO_REG_FUNC));
#endif

    /* set DIAB bit */
    UART16550_WRITE(OFS_LINE_CONTROL, 0x80);

    /* set divisor */
    UART16550_WRITE(OFS_DIVISOR_LSB, (div & 0xff));
    UART16550_WRITE(OFS_DIVISOR_MSB, ((div >> 8) & 0xff));

    /* clear DIAB bit*/ 
    UART16550_WRITE(OFS_LINE_CONTROL, 0x00);

    /* set data format */
    UART16550_WRITE(OFS_DATA_FORMAT, 0x3);

    UART16550_WRITE(OFS_INTR_ENABLE, 0);

	return 0;
}

int serial_tstc (void)
{
    return(UART16550_READ(OFS_LINE_STATUS) & 0x1);
}

int serial_getc(void)
{
    while(!serial_tstc());

    return UART16550_READ(OFS_RCV_BUFFER);
}


void serial_putc(const char byte)
{
    if (byte == '\n') serial_putc ('\r');

    while (((UART16550_READ(OFS_LINE_STATUS)) & 0x20) == 0x0);
    UART16550_WRITE(OFS_SEND_BUFFER, byte);
}

void serial_setbrg (void)
{
}

void serial_puts (const char *s)
{
	while (*s)
	{
		serial_putc (*s++);
	}
}