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
101static inline void
102nlm_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
119static inline void
120nlm_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
133static inline char
134nlm_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
153static inline int
154nlm_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__ */