[U-Boot] [PATCH 1/4 v4] serial: Add Zynq serial driver
Michal Simek
monstr at monstr.eu
Fri Sep 14 12:55:24 CEST 2012
The driver is used on Xilinx Zynq platform.
Signed-off-by: Michal Simek <monstr at monstr.eu>
CC: Joe Hershberger <joe.hershberger at gmail.com>
CC: Marek Vasut <marex at denx.de>
---
v2: Use Zynq name instead of Dragonfire and XPSS/XDFUART
Rename driver name
Remove driver description
v3: SERIAL_MULTI support
Rename xdfuart to uart_zynq
v4: Properly spell out the structure member names of serial_driver
---
common/serial.c | 8 ++
drivers/serial/Makefile | 1 +
drivers/serial/serial_zynq.c | 247 ++++++++++++++++++++++++++++++++++++++++++
include/serial.h | 5 +
4 files changed, 261 insertions(+), 0 deletions(-)
create mode 100644 drivers/serial/serial_zynq.c
diff --git a/common/serial.c b/common/serial.c
index 75cc1bb..4f2bc7f 100644
--- a/common/serial.c
+++ b/common/serial.c
@@ -122,6 +122,14 @@ void serial_initialize(void)
serial_register(&uartlite_serial3_device);
# endif /* XILINX_UARTLITE_BASEADDR3 */
#endif /* CONFIG_XILINX_UARTLITE */
+#if defined(CONFIG_ZYNQ_SERIAL)
+# ifdef CONFIG_ZYNQ_SERIAL_BASEADDR0
+ serial_register(&uart_zynq_serial0_device);
+# endif
+# ifdef CONFIG_ZYNQ_SERIAL_BASEADDR1
+ serial_register(&uart_zynq_serial1_device);
+# endif
+#endif
serial_assign(default_serial_console()->name);
}
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 65d0f23..dfc22a4 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -56,6 +56,7 @@ COBJS-$(CONFIG_S3C44B0_SERIAL) += serial_s3c44b0.o
COBJS-$(CONFIG_XILINX_UARTLITE) += serial_xuartlite.o
COBJS-$(CONFIG_SANDBOX_SERIAL) += sandbox.o
COBJS-$(CONFIG_SCIF_CONSOLE) += serial_sh.o
+COBJS-$(CONFIG_ZYNQ_SERIAL) += serial_zynq.o
ifndef CONFIG_SPL_BUILD
COBJS-$(CONFIG_USB_TTY) += usbtty.o
diff --git a/drivers/serial/serial_zynq.c b/drivers/serial/serial_zynq.c
new file mode 100644
index 0000000..3832236
--- /dev/null
+++ b/drivers/serial/serial_zynq.c
@@ -0,0 +1,247 @@
+/*
+ * Copyright (C) 2012 Michal Simek <monstr at monstr.eu>
+ * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <watchdog.h>
+#include <asm/io.h>
+#include <linux/compiler.h>
+#include <serial.h>
+
+#define ZYNQ_UART_SR_TXFULL 0x00000010 /* TX FIFO full */
+#define ZYNQ_UART_SR_RXEMPTY 0x00000002 /* RX FIFO empty */
+
+#define ZYNQ_UART_CR_TX_EN 0x00000010 /* TX enabled */
+#define ZYNQ_UART_CR_RX_EN 0x00000004 /* RX enabled */
+#define ZYNQ_UART_CR_TXRST 0x00000002 /* TX logic reset */
+#define ZYNQ_UART_CR_RXRST 0x00000001 /* RX logic reset */
+
+#define ZYNQ_UART_MR_PARITY_NONE 0x00000020 /* No parity mode */
+
+/* Some clock/baud constants */
+#define ZYNQ_UART_BDIV 15 /* Default/reset BDIV value */
+#define ZYNQ_UART_BASECLK 3125000L /* master / (bdiv + 1) */
+
+struct uart_zynq {
+ u32 control; /* Control Register [8:0] */
+ u32 mode; /* Mode Register [10:0] */
+ u32 reserved1[4];
+ u32 baud_rate_gen; /* Baud Rate Generator [15:0] */
+ u32 reserved2[4];
+ u32 channel_sts; /* Channel Status [11:0] */
+ u32 tx_rx_fifo; /* FIFO [15:0] or [7:0] */
+ u32 baud_rate_divider; /* Baud Rate Divider [7:0] */
+};
+
+static struct uart_zynq *uart_zynq_ports[2] = {
+#ifdef CONFIG_ZYNQ_SERIAL_BASEADDR0
+ [0] = (struct uart_zynq *)CONFIG_ZYNQ_SERIAL_BASEADDR0,
+#endif
+#ifdef CONFIG_ZYNQ_SERIAL_BASEADDR1
+ [1] = (struct uart_zynq *)CONFIG_ZYNQ_SERIAL_BASEADDR1,
+#endif
+};
+
+struct uart_zynq_params {
+ u32 baudrate;
+ u32 clock;
+};
+
+static struct uart_zynq_params uart_zynq_ports_param[2] = {
+#if defined(CONFIG_ZYNQ_SERIAL_BAUDRATE0) && defined(CONFIG_ZYNQ_SERIAL_CLOCK0)
+ [0].baudrate = CONFIG_ZYNQ_SERIAL_BAUDRATE0,
+ [0].clock = CONFIG_ZYNQ_SERIAL_CLOCK0,
+#endif
+#if defined(CONFIG_ZYNQ_SERIAL_BAUDRATE1) && defined(CONFIG_ZYNQ_SERIAL_CLOCK1)
+ [1].baudrate = CONFIG_ZYNQ_SERIAL_BAUDRATE1,
+ [1].clock = CONFIG_ZYNQ_SERIAL_CLOCK1,
+#endif
+};
+
+/* Set up the baud rate in gd struct */
+static void uart_zynq_serial_setbrg(const int port)
+{
+ /* Calculation results. */
+ unsigned int calc_bauderror, bdiv, bgen;
+ unsigned long calc_baud = 0;
+ unsigned long baud = uart_zynq_ports_param[port].baudrate;
+ unsigned long clock = uart_zynq_ports_param[port].clock;
+ struct uart_zynq *regs = uart_zynq_ports[port];
+
+ /* master clock
+ * Baud rate = ------------------
+ * bgen * (bdiv + 1)
+ *
+ * Find acceptable values for baud generation.
+ */
+ for (bdiv = 4; bdiv < 255; bdiv++) {
+ bgen = clock / (baud * (bdiv + 1));
+ if (bgen < 2 || bgen > 65535)
+ continue;
+
+ calc_baud = clock / (bgen * (bdiv + 1));
+
+ /*
+ * Use first calculated baudrate with
+ * an acceptable (<3%) error
+ */
+ if (baud > calc_baud)
+ calc_bauderror = baud - calc_baud;
+ else
+ calc_bauderror = calc_baud - baud;
+ if (((calc_bauderror * 100) / baud) < 3)
+ break;
+ }
+
+ writel(bdiv, ®s->baud_rate_divider);
+ writel(bgen, ®s->baud_rate_gen);
+}
+
+/* Initialize the UART, with...some settings. */
+static int uart_zynq_serial_init(const int port)
+{
+ struct uart_zynq *regs = uart_zynq_ports[port];
+
+ if (!regs)
+ return -1;
+
+ /* RX/TX enabled & reset */
+ writel(ZYNQ_UART_CR_TX_EN | ZYNQ_UART_CR_RX_EN | ZYNQ_UART_CR_TXRST | \
+ ZYNQ_UART_CR_RXRST, ®s->control);
+ writel(ZYNQ_UART_MR_PARITY_NONE, ®s->mode); /* 8 bit, no parity */
+ uart_zynq_serial_setbrg(port);
+
+ return 0;
+}
+
+static void uart_zynq_serial_putc(const char c, const int port)
+{
+ struct uart_zynq *regs = uart_zynq_ports[port];
+
+ while ((readl(®s->channel_sts) & ZYNQ_UART_SR_TXFULL) != 0)
+ WATCHDOG_RESET();
+
+ if (c == '\n') {
+ writel('\r', ®s->tx_rx_fifo);
+ while ((readl(®s->channel_sts) & ZYNQ_UART_SR_TXFULL) != 0)
+ WATCHDOG_RESET();
+ }
+ writel(c, ®s->tx_rx_fifo);
+}
+
+static void uart_zynq_serial_puts(const char *s, const int port)
+{
+ while (*s)
+ uart_zynq_serial_putc(*s++, port);
+}
+
+static int uart_zynq_serial_tstc(const int port)
+{
+ struct uart_zynq *regs = uart_zynq_ports[port];
+
+ return (readl(®s->channel_sts) & ZYNQ_UART_SR_RXEMPTY) == 0;
+}
+
+static int uart_zynq_serial_getc(const int port)
+{
+ struct uart_zynq *regs = uart_zynq_ports[port];
+
+ while (!uart_zynq_serial_tstc(port))
+ WATCHDOG_RESET();
+ return readl(®s->tx_rx_fifo);
+}
+
+#if !defined(CONFIG_SERIAL_MULTI)
+int serial_init(void)
+{
+ return uart_zynq_serial_init(0);
+}
+
+void serial_setbrg(void)
+{
+ uart_zynq_serial_setbrg(0);
+}
+
+void serial_putc(const char c)
+{
+ uart_zynq_serial_putc(c, 0);
+}
+
+void serial_puts(const char *s)
+{
+ uart_zynq_serial_puts(s, 0);
+}
+
+int serial_getc(void)
+{
+ return uart_zynq_serial_getc(0);
+}
+
+int serial_tstc(void)
+{
+ return uart_zynq_serial_tstc(0);
+}
+#else
+/* Multi serial device functions */
+#define DECLARE_PSSERIAL_FUNCTIONS(port) \
+ int uart_zynq##port##_init(void) \
+ { return uart_zynq_serial_init(port); } \
+ void uart_zynq##port##_setbrg(void) \
+ { return uart_zynq_serial_setbrg(port); } \
+ int uart_zynq##port##_getc(void) \
+ { return uart_zynq_serial_getc(port); } \
+ int uart_zynq##port##_tstc(void) \
+ { return uart_zynq_serial_tstc(port); } \
+ void uart_zynq##port##_putc(const char c) \
+ { uart_zynq_serial_putc(c, port); } \
+ void uart_zynq##port##_puts(const char *s) \
+ { uart_zynq_serial_puts(s, port); }
+
+/* Serial device descriptor */
+#define INIT_PSSERIAL_STRUCTURE(port, __name) { \
+ .name = __name, \
+ .init = uart_zynq##port##_init, \
+ .uninit = NULL, \
+ .setbrg = uart_zynq##port##_setbrg, \
+ .getc = uart_zynq##port##_getc, \
+ .tstc = uart_zynq##port##_tstc, \
+ .putc = uart_zynq##port##_putc, \
+ .puts = uart_zynq##port##_puts, \
+}
+
+DECLARE_PSSERIAL_FUNCTIONS(0);
+struct serial_device uart_zynq_serial0_device =
+ INIT_PSSERIAL_STRUCTURE(0, "ttyPS0");
+DECLARE_PSSERIAL_FUNCTIONS(1);
+struct serial_device uart_zynq_serial1_device =
+ INIT_PSSERIAL_STRUCTURE(1, "ttyPS1");
+
+__weak struct serial_device *default_serial_console(void)
+{
+ if (uart_zynq_ports[0])
+ return &uart_zynq_serial0_device;
+ if (uart_zynq_ports[1])
+ return &uart_zynq_serial1_device;
+
+ return NULL;
+}
+#endif
diff --git a/include/serial.h b/include/serial.h
index d76d6df..826b488 100644
--- a/include/serial.h
+++ b/include/serial.h
@@ -90,6 +90,11 @@ extern struct serial_device bfin_serial2_device;
extern struct serial_device bfin_serial3_device;
#endif
+#if defined(CONFIG_ZYNQ_SERIAL)
+extern struct serial_device uart_zynq_serial0_device;
+extern struct serial_device uart_zynq_serial1_device;
+#endif
+
extern void serial_register(struct serial_device *);
extern void serial_initialize(void);
extern void serial_stdio_init(void);
--
1.7.0.4
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