--- /dev/null
+/*
+ * (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 s5pc1xx_uart *s5pc1xx_get_base_uart(int dev_index)
+{
+ u32 offset = dev_index * sizeof(struct s5pc1xx_uart);
+
+ if (cpu_is_s5pc100())
+ return (struct s5pc1xx_uart *)(S5PC100_UART_BASE + offset);
+ else
+ return (struct s5pc1xx_uart *)(S5PC110_UART_BASE + offset);
+}
+
+/*
+ * The coefficient, used to calculate the baudrate on S5PC1XX 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 s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
+ u32 pclk = get_pclk();
+ u32 baudrate = gd->baudrate;
+ u32 val;
+
+ val = pclk / baudrate;
+
+ writel(val / 16 - 1, &uart->ubrdiv);
+ writel(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 s5pc1xx_uart *const uart = s5pc1xx_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)
+{
+ struct s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
+
+ if (readl(&uart->uerstat) & 0xf)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * 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 s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
+
+ /* wait for character to arrive */
+ while (!(readl(&uart->utrstat) & 0x1)) {
+ if (serial_err_check(dev_index))
+ 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 s5pc1xx_uart *const uart = s5pc1xx_get_base_uart(dev_index);
+
+ /* wait for room in the tx FIFO */
+ while (!(readl(&uart->utrstat) & 0x2)) {
+ if (serial_err_check(dev_index))
+ 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 s5pc1xx_uart *const uart = s5pc1xx_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, \
+ 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 s5pc1xx_serial0_device =
+ INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0", "S5PUART0");
+DECLARE_S5P_SERIAL_FUNCTIONS(1);
+struct serial_device s5pc1xx_serial1_device =
+ INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1", "S5PUART1");
+DECLARE_S5P_SERIAL_FUNCTIONS(2);
+struct serial_device s5pc1xx_serial2_device =
+ INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2", "S5PUART2");
+DECLARE_S5P_SERIAL_FUNCTIONS(3);
+struct serial_device s5pc1xx_serial3_device =
+ INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3", "S5PUART3");
projects / platform / kernel / u-boot.git / commitdiff