1 /*
2 * Copyright 2003-2011 NetLogic Microsystems, Inc. (NetLogic). All rights
3 * reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the NetLogic
9 * license below:
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in
19 * the documentation and/or other materials provided with the
20 * distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY NETLOGIC ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL NETLOGIC OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
31 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
32 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35 #ifndef __XLP_HAL_UART_H__
36 #define __XLP_HAL_UART_H__
37
38 /* UART Specific registers */
39 #define UART_RX_DATA 0x00
40 #define UART_TX_DATA 0x00
41
42 #define UART_INT_EN 0x01
43 #define UART_INT_ID 0x02
44 #define UART_FIFO_CTL 0x02
45 #define UART_LINE_CTL 0x03
46 #define UART_MODEM_CTL 0x04
47 #define UART_LINE_STS 0x05
48 #define UART_MODEM_STS 0x06
49
50 #define UART_DIVISOR0 0x00
51 #define UART_DIVISOR1 0x01
52
53 #define BASE_BAUD (XLP_IO_CLK/16)
54 #define BAUD_DIVISOR(baud) (BASE_BAUD / baud)
55
56 /* LCR mask values */
57 #define LCR_5BITS 0x00
58 #define LCR_6BITS 0x01
59 #define LCR_7BITS 0x02
60 #define LCR_8BITS 0x03
61 #define LCR_STOPB 0x04
62 #define LCR_PENAB 0x08
63 #define LCR_PODD 0x00
64 #define LCR_PEVEN 0x10
65 #define LCR_PONE 0x20
66 #define LCR_PZERO 0x30
67 #define LCR_SBREAK 0x40
68 #define LCR_EFR_ENABLE 0xbf
69 #define LCR_DLAB 0x80
70
71 /* MCR mask values */
72 #define MCR_DTR 0x01
73 #define MCR_RTS 0x02
74 #define MCR_DRS 0x04
75 #define MCR_IE 0x08
76 #define MCR_LOOPBACK 0x10
77
78 /* FCR mask values */
79 #define FCR_RCV_RST 0x02
80 #define FCR_XMT_RST 0x04
81 #define FCR_RX_LOW 0x00
82 #define FCR_RX_MEDL 0x40
83 #define FCR_RX_MEDH 0x80
84 #define FCR_RX_HIGH 0xc0
85
86 /* IER mask values */
87 #define IER_ERXRDY 0x1
88 #define IER_ETXRDY 0x2
89 #define IER_ERLS 0x4
90 #define IER_EMSC 0x8
91
92 #if !defined(LOCORE) && !defined(__ASSEMBLY__)
93
94 #define nlm_read_uart_reg(b, r) nlm_read_reg(b, r)
95 #define nlm_write_uart_reg(b, r, v) nlm_write_reg(b, r, v)
96 #define nlm_get_uart_pcibase(node, inst) \
97 nlm_pcicfg_base(XLP_IO_UART_OFFSET(node, inst))
98 #define nlm_get_uart_regbase(node, inst) \
99 (nlm_get_uart_pcibase(node, inst) + XLP_IO_PCI_HDRSZ)
100
101 static inline void
nlm_uart_set_baudrate(uint64_t base,int baud)102 nlm_uart_set_baudrate(uint64_t base, int baud)
103 {
104 uint32_t lcr;
105
106 lcr = nlm_read_uart_reg(base, UART_LINE_CTL);
107
108 /* enable divisor register, and write baud values */
109 nlm_write_uart_reg(base, UART_LINE_CTL, lcr | (1 << 7));
110 nlm_write_uart_reg(base, UART_DIVISOR0,
111 (BAUD_DIVISOR(baud) & 0xff));
112 nlm_write_uart_reg(base, UART_DIVISOR1,
113 ((BAUD_DIVISOR(baud) >> 8) & 0xff));
114
115 /* restore default lcr */
116 nlm_write_uart_reg(base, UART_LINE_CTL, lcr);
117 }
118
119 static inline void
nlm_uart_outbyte(uint64_t base,char c)120 nlm_uart_outbyte(uint64_t base, char c)
121 {
122 uint32_t lsr;
123
124 for (;;) {
125 lsr = nlm_read_uart_reg(base, UART_LINE_STS);
126 if (lsr & 0x20)
127 break;
128 }
129
130 nlm_write_uart_reg(base, UART_TX_DATA, (int)c);
131 }
132
133 static inline char
nlm_uart_inbyte(uint64_t base)134 nlm_uart_inbyte(uint64_t base)
135 {
136 int data, lsr;
137
138 for (;;) {
139 lsr = nlm_read_uart_reg(base, UART_LINE_STS);
140 if (lsr & 0x80) { /* parity/frame/break-error - push a zero */
141 data = 0;
142 break;
143 }
144 if (lsr & 0x01) { /* Rx data */
145 data = nlm_read_uart_reg(base, UART_RX_DATA);
146 break;
147 }
148 }
149
150 return (char)data;
151 }
152
153 static inline int
nlm_uart_init(uint64_t base,int baud,int databits,int stopbits,int parity,int int_en,int loopback)154 nlm_uart_init(uint64_t base, int baud, int databits, int stopbits,
155 int parity, int int_en, int loopback)
156 {
157 uint32_t lcr;
158
159 lcr = 0;
160 if (databits >= 8)
161 lcr |= LCR_8BITS;
162 else if (databits == 7)
163 lcr |= LCR_7BITS;
164 else if (databits == 6)
165 lcr |= LCR_6BITS;
166 else
167 lcr |= LCR_5BITS;
168
169 if (stopbits > 1)
170 lcr |= LCR_STOPB;
171
172 lcr |= parity << 3;
173
174 /* setup default lcr */
175 nlm_write_uart_reg(base, UART_LINE_CTL, lcr);
176
177 /* Reset the FIFOs */
178 nlm_write_uart_reg(base, UART_LINE_CTL, FCR_RCV_RST | FCR_XMT_RST);
179
180 nlm_uart_set_baudrate(base, baud);
181
182 if (loopback)
183 nlm_write_uart_reg(base, UART_MODEM_CTL, 0x1f);
184
185 if (int_en)
186 nlm_write_uart_reg(base, UART_INT_EN, IER_ERXRDY | IER_ETXRDY);
187
188 return 0;
189 }
190 #endif /* !LOCORE && !__ASSEMBLY__ */
191 #endif /* __XLP_HAL_UART_H__ */
192