2 * (C) Copyright 2009 SAMSUNG Electronics
3 * Minkyu Kang <mk7.kang@samsung.com>
4 * Heungjun Kim <riverful.kim@samsung.com>
6 * based on drivers/serial/s3c64xx.c
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <asm/arch/uart.h>
27 #include <asm/arch/clk.h>
30 static inline struct s5pc1xx_uart *s5pc1xx_get_base_uart(int dev_index)
32 u32 offset = dev_index * sizeof(struct s5pc1xx_uart);
35 return (struct s5pc1xx_uart *)(S5PC100_UART_BASE + offset);
37 return (struct s5pc1xx_uart *)(S5PC110_UART_BASE + offset);
41 * The coefficient, used to calculate the baudrate on S5PC1XX UARTs is
43 * C = UBRDIV * 16 + number_of_set_bits_in_UDIVSLOT
44 * however, section 31.6.11 of the datasheet doesn't recomment using 1 for 1,
45 * 3 for 2, ... (2^n - 1) for n, instead, they suggest using these constants:
47 static const int udivslot[] = {
66 void serial_setbrg_dev(const int dev_index)
68 DECLARE_GLOBAL_DATA_PTR;
69 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
70 u32 pclk = get_pclk();
71 u32 baudrate = gd->baudrate;
74 val = pclk / baudrate;
76 writel(val / 16 - 1, &uart->ubrdiv);
77 writel(udivslot[val % 16], &uart->udivslot);
81 * Initialise the serial port with the given baudrate. The settings
82 * are always 8 data bits, no parity, 1 stop bit, no start bits.
84 int serial_init_dev(const int dev_index)
86 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
88 /* reset and enable FIFOs, set triggers to the maximum */
89 writel(0, &uart->ufcon);
90 writel(0, &uart->umcon);
92 writel(0x3, &uart->ulcon);
93 /* No interrupts, no DMA, pure polling */
94 writel(0x245, &uart->ucon);
96 serial_setbrg_dev(dev_index);
101 static int serial_err_check(const int dev_index)
103 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
105 if (readl(&uart->uerstat) & 0xf)
112 * Read a single byte from the serial port. Returns 1 on success, 0
113 * otherwise. When the function is succesfull, the character read is
114 * written into its argument c.
116 int serial_getc_dev(const int dev_index)
118 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
120 /* wait for character to arrive */
121 while (!(readl(&uart->utrstat) & 0x1)) {
122 if (serial_err_check(dev_index))
126 return (int)(readl(&uart->urxh) & 0xff);
130 * Output a single byte to the serial port.
132 void serial_putc_dev(const char c, const int dev_index)
134 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
136 /* wait for room in the tx FIFO */
137 while (!(readl(&uart->utrstat) & 0x2)) {
138 if (serial_err_check(dev_index))
142 writel(c, &uart->utxh);
144 /* If \n, also do \r */
150 * Test whether a character is in the RX buffer
152 int serial_tstc_dev(const int dev_index)
154 struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
156 return (int)(readl(&uart->utrstat) & 0x1);
159 void serial_puts_dev(const char *s, const int dev_index)
162 serial_putc_dev(*s++, dev_index);
165 /* Multi serial device functions */
166 #define DECLARE_S5P_SERIAL_FUNCTIONS(port) \
167 int s5p_serial##port##_init(void) { return serial_init_dev(port); } \
168 void s5p_serial##port##_setbrg(void) { serial_setbrg_dev(port); } \
169 int s5p_serial##port##_getc(void) { return serial_getc_dev(port); } \
170 int s5p_serial##port##_tstc(void) { return serial_tstc_dev(port); } \
171 void s5p_serial##port##_putc(const char c) { serial_putc_dev(c, port); } \
172 void s5p_serial##port##_puts(const char *s) { serial_puts_dev(s, port); }
174 #define INIT_S5P_SERIAL_STRUCTURE(port, name, bus) { \
177 s5p_serial##port##_init, \
178 s5p_serial##port##_setbrg, \
179 s5p_serial##port##_getc, \
180 s5p_serial##port##_tstc, \
181 s5p_serial##port##_putc, \
182 s5p_serial##port##_puts, }
184 DECLARE_S5P_SERIAL_FUNCTIONS(0);
185 struct serial_device s5pc1xx_serial0_device =
186 INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0", "S5PUART0");
187 DECLARE_S5P_SERIAL_FUNCTIONS(1);
188 struct serial_device s5pc1xx_serial1_device =
189 INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1", "S5PUART1");
190 DECLARE_S5P_SERIAL_FUNCTIONS(2);
191 struct serial_device s5pc1xx_serial2_device =
192 INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2", "S5PUART2");
193 DECLARE_S5P_SERIAL_FUNCTIONS(3);
194 struct serial_device s5pc1xx_serial3_device =
195 INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3", "S5PUART3");