[people/ms/u-boot.git] / drivers / serial / serial_s5p.c

/*
 * (C) Copyright 2009 SAMSUNG Electronics
 * Minkyu Kang <mk7.kang@samsung.com>
 * Heungjun Kim <riverful.kim@samsung.com>
 *
 * based on drivers/serial/s3c64xx.c
 *
 * 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 <common.h>
#include <asm/io.h>
#include <asm/arch/uart.h>
#include <asm/arch/clk.h>
#include <serial.h>

static inline struct s5p_uart *s5p_get_base_uart(int dev_index)
{
	u32 offset = dev_index * sizeof(struct s5p_uart);

	if (cpu_is_s5pc100())
		return (struct s5p_uart *)(S5PC100_UART_BASE + offset);
	else
		return (struct s5p_uart *)(S5PC110_UART_BASE + offset);
}

/*
 * The coefficient, used to calculate the baudrate on S5P UARTs is
 * calculated as
 * C = UBRDIV * 16 + number_of_set_bits_in_UDIVSLOT
 * however, section 31.6.11 of the datasheet doesn't recomment using 1 for 1,
 * 3 for 2, ... (2^n - 1) for n, instead, they suggest using these constants:
 */
static const int udivslot[] = {
	0,
	0x0080,
	0x0808,
	0x0888,
	0x2222,
	0x4924,
	0x4a52,
	0x54aa,
	0x5555,
	0xd555,
	0xd5d5,
	0xddd5,
	0xdddd,
	0xdfdd,
	0xdfdf,
	0xffdf,
};

void serial_setbrg_dev(const int dev_index)
{
	DECLARE_GLOBAL_DATA_PTR;
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
	u32 pclk = get_pclk();
	u32 baudrate = gd->baudrate;
	u32 val;

	val = pclk / baudrate;

	writel(val / 16 - 1, &uart->ubrdiv);
	writew(udivslot[val % 16], &uart->udivslot);
}

/*
 * Initialise the serial port with the given baudrate. The settings
 * are always 8 data bits, no parity, 1 stop bit, no start bits.
 */
int serial_init_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	/* reset and enable FIFOs, set triggers to the maximum */
	writel(0, &uart->ufcon);
	writel(0, &uart->umcon);
	/* 8N1 */
	writel(0x3, &uart->ulcon);
	/* No interrupts, no DMA, pure polling */
	writel(0x245, &uart->ucon);

	serial_setbrg_dev(dev_index);

	return 0;
}

static int serial_err_check(const int dev_index, int op)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
	unsigned int mask;

	/*
	 * UERSTAT
	 * Break Detect	[3]
	 * Frame Err	[2] : receive operation
	 * Parity Err	[1] : receive operation
	 * Overrun Err	[0] : receive operation
	 */
	if (op)
		mask = 0x8;
	else
		mask = 0xf;

	return readl(&uart->uerstat) & mask;
}

/*
 * Read a single byte from the serial port. Returns 1 on success, 0
 * otherwise. When the function is succesfull, the character read is
 * written into its argument c.
 */
int serial_getc_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	/* wait for character to arrive */
	while (!(readl(&uart->utrstat) & 0x1)) {
		if (serial_err_check(dev_index, 0))
			return 0;
	}

	return (int)(readl(&uart->urxh) & 0xff);
}

/*
 * Output a single byte to the serial port.
 */
void serial_putc_dev(const char c, const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	/* wait for room in the tx FIFO */
	while (!(readl(&uart->utrstat) & 0x2)) {
		if (serial_err_check(dev_index, 1))
			return;
	}

	writel(c, &uart->utxh);

	/* If \n, also do \r */
	if (c == '\n')
		serial_putc('\r');
}

/*
 * Test whether a character is in the RX buffer
 */
int serial_tstc_dev(const int dev_index)
{
	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);

	return (int)(readl(&uart->utrstat) & 0x1);
}

void serial_puts_dev(const char *s, const int dev_index)
{
	while (*s)
		serial_putc_dev(*s++, dev_index);
}

/* Multi serial device functions */
#define DECLARE_S5P_SERIAL_FUNCTIONS(port) \
int s5p_serial##port##_init(void) { return serial_init_dev(port); } \
void s5p_serial##port##_setbrg(void) { serial_setbrg_dev(port); } \
int s5p_serial##port##_getc(void) { return serial_getc_dev(port); } \
int s5p_serial##port##_tstc(void) { return serial_tstc_dev(port); } \
void s5p_serial##port##_putc(const char c) { serial_putc_dev(c, port); } \
void s5p_serial##port##_puts(const char *s) { serial_puts_dev(s, port); }

#define INIT_S5P_SERIAL_STRUCTURE(port, name, bus) { \
	name, \
	bus, \
	s5p_serial##port##_init, \
	NULL, \
	s5p_serial##port##_setbrg, \
	s5p_serial##port##_getc, \
	s5p_serial##port##_tstc, \
	s5p_serial##port##_putc, \
	s5p_serial##port##_puts, }

DECLARE_S5P_SERIAL_FUNCTIONS(0);
struct serial_device s5p_serial0_device =
	INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0", "S5PUART0");
DECLARE_S5P_SERIAL_FUNCTIONS(1);
struct serial_device s5p_serial1_device =
	INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1", "S5PUART1");
DECLARE_S5P_SERIAL_FUNCTIONS(2);
struct serial_device s5p_serial2_device =
	INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2", "S5PUART2");
DECLARE_S5P_SERIAL_FUNCTIONS(3);
struct serial_device s5p_serial3_device =
	INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3", "S5PUART3");
Commit	Line	Data
dd2c9e6a MK	1	/*
	2	* (C) Copyright 2009 SAMSUNG Electronics
	3	* Minkyu Kang <mk7.kang@samsung.com>
	4	* Heungjun Kim <riverful.kim@samsung.com>
	5	*
	6	* based on drivers/serial/s3c64xx.c
	7	*
	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.
	12	*
	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.
	17	*
	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
	21	*
	22	*/
	23
	24	#include <common.h>
	25	#include <asm/io.h>
	26	#include <asm/arch/uart.h>
	27	#include <asm/arch/clk.h>
	28	#include <serial.h>
	29
46a3b5c8	30	static inline struct s5p_uart *s5p_get_base_uart(int dev_index)
dd2c9e6a	31	{
46a3b5c8	32	u32 offset = dev_index * sizeof(struct s5p_uart);
dd2c9e6a MK	33
dd2c9e6a MK	34	if (cpu_is_s5pc100())
46a3b5c8	35	return (struct s5p_uart *)(S5PC100_UART_BASE + offset);
dd2c9e6a	36	else
46a3b5c8	37	return (struct s5p_uart *)(S5PC110_UART_BASE + offset);
dd2c9e6a MK	38	}
	39
	40	/*
46a3b5c8	41	* The coefficient, used to calculate the baudrate on S5P UARTs is
dd2c9e6a MK	42	* calculated as
	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:
	46	*/
	47	static const int udivslot[] = {
	48	0,
	49	0x0080,
	50	0x0808,
	51	0x0888,
	52	0x2222,
	53	0x4924,
	54	0x4a52,
	55	0x54aa,
	56	0x5555,
	57	0xd555,
	58	0xd5d5,
	59	0xddd5,
	60	0xdddd,
	61	0xdfdd,
	62	0xdfdf,
	63	0xffdf,
	64	};
	65
	66	void serial_setbrg_dev(const int dev_index)
	67	{
	68	DECLARE_GLOBAL_DATA_PTR;
46a3b5c8	69	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
dd2c9e6a MK	70	u32 pclk = get_pclk();
	71	u32 baudrate = gd->baudrate;
	72	u32 val;
	73
	74	val = pclk / baudrate;
	75
	76	writel(val / 16 - 1, &uart->ubrdiv);
f3807374	77	writew(udivslot[val % 16], &uart->udivslot);
dd2c9e6a MK	78	}
	79
	80	/*
	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.
	83	*/
	84	int serial_init_dev(const int dev_index)
	85	{
46a3b5c8	86	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
dd2c9e6a MK	87
	88	/* reset and enable FIFOs, set triggers to the maximum */
	89	writel(0, &uart->ufcon);
	90	writel(0, &uart->umcon);
	91	/* 8N1 */
	92	writel(0x3, &uart->ulcon);
	93	/* No interrupts, no DMA, pure polling */
	94	writel(0x245, &uart->ucon);
	95
	96	serial_setbrg_dev(dev_index);
	97
	98	return 0;
	99	}
	100
94003226	101	static int serial_err_check(const int dev_index, int op)
dd2c9e6a	102	{
46a3b5c8	103	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
94003226 MK	104	unsigned int mask;
	105
	106	/*
	107	* UERSTAT
	108	* Break Detect [3]
	109	* Frame Err [2] : receive operation
	110	* Parity Err [1] : receive operation
	111	* Overrun Err [0] : receive operation
	112	*/
	113	if (op)
	114	mask = 0x8;
	115	else
	116	mask = 0xf;
dd2c9e6a	117
94003226	118	return readl(&uart->uerstat) & mask;
dd2c9e6a MK	119	}
	120
	121	/*
	122	* Read a single byte from the serial port. Returns 1 on success, 0
	123	* otherwise. When the function is succesfull, the character read is
	124	* written into its argument c.
	125	*/
	126	int serial_getc_dev(const int dev_index)
	127	{
46a3b5c8	128	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
dd2c9e6a MK	129
	130	/* wait for character to arrive */
	131	while (!(readl(&uart->utrstat) & 0x1)) {
94003226	132	if (serial_err_check(dev_index, 0))
dd2c9e6a MK	133	return 0;
	134	}
	135
	136	return (int)(readl(&uart->urxh) & 0xff);
	137	}
	138
	139	/*
	140	* Output a single byte to the serial port.
	141	*/
	142	void serial_putc_dev(const char c, const int dev_index)
	143	{
46a3b5c8	144	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
dd2c9e6a MK	145
	146	/* wait for room in the tx FIFO */
	147	while (!(readl(&uart->utrstat) & 0x2)) {
94003226	148	if (serial_err_check(dev_index, 1))
dd2c9e6a MK	149	return;
	150	}
	151
	152	writel(c, &uart->utxh);
	153
	154	/* If \n, also do \r */
	155	if (c == '\n')
	156	serial_putc('\r');
	157	}
	158
	159	/*
	160	* Test whether a character is in the RX buffer
	161	*/
	162	int serial_tstc_dev(const int dev_index)
	163	{
46a3b5c8	164	struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
dd2c9e6a MK	165
	166	return (int)(readl(&uart->utrstat) & 0x1);
	167	}
	168
	169	void serial_puts_dev(const char *s, const int dev_index)
	170	{
	171	while (*s)
	172	serial_putc_dev(*s++, dev_index);
	173	}
	174
	175	/* Multi serial device functions */
	176	#define DECLARE_S5P_SERIAL_FUNCTIONS(port) \
	177	int s5p_serial##port##_init(void) { return serial_init_dev(port); } \
	178	void s5p_serial##port##_setbrg(void) { serial_setbrg_dev(port); } \
	179	int s5p_serial##port##_getc(void) { return serial_getc_dev(port); } \
	180	int s5p_serial##port##_tstc(void) { return serial_tstc_dev(port); } \
	181	void s5p_serial##port##_putc(const char c) { serial_putc_dev(c, port); } \
	182	void s5p_serial##port##_puts(const char *s) { serial_puts_dev(s, port); }
	183
	184	#define INIT_S5P_SERIAL_STRUCTURE(port, name, bus) { \
	185	name, \
	186	bus, \
	187	s5p_serial##port##_init, \
fbb0030e	188	NULL, \
dd2c9e6a MK	189	s5p_serial##port##_setbrg, \
	190	s5p_serial##port##_getc, \
	191	s5p_serial##port##_tstc, \
	192	s5p_serial##port##_putc, \
	193	s5p_serial##port##_puts, }
	194
	195	DECLARE_S5P_SERIAL_FUNCTIONS(0);
46a3b5c8	196	struct serial_device s5p_serial0_device =
dd2c9e6a MK	197	INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0", "S5PUART0");
dd2c9e6a MK	198	DECLARE_S5P_SERIAL_FUNCTIONS(1);
46a3b5c8	199	struct serial_device s5p_serial1_device =
dd2c9e6a MK	200	INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1", "S5PUART1");
dd2c9e6a MK	201	DECLARE_S5P_SERIAL_FUNCTIONS(2);
46a3b5c8	202	struct serial_device s5p_serial2_device =
dd2c9e6a MK	203	INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2", "S5PUART2");
dd2c9e6a MK	204	DECLARE_S5P_SERIAL_FUNCTIONS(3);
46a3b5c8	205	struct serial_device s5p_serial3_device =
dd2c9e6a	206	INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3", "S5PUART3");