--- /dev/null
+/*
+ * Copyright (C) 2012 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <watchdog.h>
+#include <asm/io.h>
+#include <linux/compiler.h>
+#include <serial.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/hardware.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#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 */
+
+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] = {
+ [0] = (struct uart_zynq *)ZYNQ_SERIAL_BASEADDR0,
+ [1] = (struct uart_zynq *)ZYNQ_SERIAL_BASEADDR1,
+};
+
+#if !defined(CONFIG_ZYNQ_SERIAL_BAUDRATE0)
+# define CONFIG_ZYNQ_SERIAL_BAUDRATE0 CONFIG_BAUDRATE
+#endif
+#if !defined(CONFIG_ZYNQ_SERIAL_BAUDRATE1)
+# define CONFIG_ZYNQ_SERIAL_BAUDRATE1 CONFIG_BAUDRATE
+#endif
+
+struct uart_zynq_params {
+ u32 baudrate;
+};
+
+static struct uart_zynq_params uart_zynq_ports_param[2] = {
+ [0].baudrate = CONFIG_ZYNQ_SERIAL_BAUDRATE0,
+ [1].baudrate = CONFIG_ZYNQ_SERIAL_BAUDRATE1,
+};
+
+/* 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 = get_uart_clk(port);
+ 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);
+}
+
+/* Multi serial device functions */
+#define DECLARE_PSSERIAL_FUNCTIONS(port) \
+ static int uart_zynq##port##_init(void) \
+ { return uart_zynq_serial_init(port); } \
+ static void uart_zynq##port##_setbrg(void) \
+ { return uart_zynq_serial_setbrg(port); } \
+ static int uart_zynq##port##_getc(void) \
+ { return uart_zynq_serial_getc(port); } \
+ static int uart_zynq##port##_tstc(void) \
+ { return uart_zynq_serial_tstc(port); } \
+ static void uart_zynq##port##_putc(const char c) \
+ { uart_zynq_serial_putc(c, port); } \
+ static 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, \
+ .start = uart_zynq##port##_init, \
+ .stop = 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);
+static struct serial_device uart_zynq_serial0_device =
+ INIT_PSSERIAL_STRUCTURE(0, "ttyPS0");
+DECLARE_PSSERIAL_FUNCTIONS(1);
+static struct serial_device uart_zynq_serial1_device =
+ INIT_PSSERIAL_STRUCTURE(1, "ttyPS1");
+
+#ifdef CONFIG_OF_CONTROL
+__weak struct serial_device *default_serial_console(void)
+{
+ const void *blob = gd->fdt_blob;
+ int node;
+ unsigned int base_addr;
+
+ node = fdt_path_offset(blob, "serial0");
+ if (node < 0)
+ return NULL;
+
+ base_addr = fdtdec_get_addr(blob, node, "reg");
+ if (base_addr == FDT_ADDR_T_NONE)
+ return NULL;
+
+ if (base_addr == ZYNQ_SERIAL_BASEADDR0)
+ return &uart_zynq_serial0_device;
+
+ if (base_addr == ZYNQ_SERIAL_BASEADDR1)
+ return &uart_zynq_serial1_device;
+
+ return NULL;
+}
+#else
+__weak struct serial_device *default_serial_console(void)
+{
+#if defined(CONFIG_ZYNQ_SERIAL_UART0)
+ if (uart_zynq_ports[0])
+ return &uart_zynq_serial0_device;
+#endif
+#if defined(CONFIG_ZYNQ_SERIAL_UART1)
+ if (uart_zynq_ports[1])
+ return &uart_zynq_serial1_device;
+#endif
+ return NULL;
+}
+#endif
+
+void zynq_serial_initialize(void)
+{
+ serial_register(&uart_zynq_serial0_device);
+ serial_register(&uart_zynq_serial1_device);
+}
Code Review / kvmfornfv.git / blobdiff