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-rw-r--r--post/cpu/ppc4xx/uart.c215
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diff --git a/post/cpu/ppc4xx/uart.c b/post/cpu/ppc4xx/uart.c
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+/*
+ * (C) Copyright 2007
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * Author: Igor Lisitsin <igor@emcraft.com>
+ *
+ * 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>
+
+/*
+ * UART test
+ *
+ * The controllers are configured to loopback mode and several
+ * characters are transmitted.
+ */
+
+#ifdef CONFIG_POST
+
+#include <post.h>
+
+#if CONFIG_POST & CFG_POST_UART
+
+#include <asm/processor.h>
+#include <serial.h>
+
+#define UART0_BASE CFG_PERIPHERAL_BASE + 0x00000300
+#define UART1_BASE CFG_PERIPHERAL_BASE + 0x00000400
+#define UART2_BASE CFG_PERIPHERAL_BASE + 0x00000500
+#define UART3_BASE CFG_PERIPHERAL_BASE + 0x00000600
+
+#define CR0_MASK 0xdfffffff
+#define CR0_EXTCLK_ENA 0x00800000
+#define CR0_UDIV_POS 0
+#define UDIV_SUBTRACT 0
+#define UART0_SDR sdr_uart0
+#define UART1_SDR sdr_uart1
+#define UART2_SDR sdr_uart2
+#define UART3_SDR sdr_uart3
+#define MFREG(a, d) mfsdr(a, d)
+#define MTREG(a, d) mtsdr(a, d)
+
+#define UART_RBR 0x00
+#define UART_THR 0x00
+#define UART_IER 0x01
+#define UART_IIR 0x02
+#define UART_FCR 0x02
+#define UART_LCR 0x03
+#define UART_MCR 0x04
+#define UART_LSR 0x05
+#define UART_MSR 0x06
+#define UART_SCR 0x07
+#define UART_DLL 0x00
+#define UART_DLM 0x01
+
+/*
+ Line Status Register.
+*/
+#define asyncLSRDataReady1 0x01
+#define asyncLSROverrunError1 0x02
+#define asyncLSRParityError1 0x04
+#define asyncLSRFramingError1 0x08
+#define asyncLSRBreakInterrupt1 0x10
+#define asyncLSRTxHoldEmpty1 0x20
+#define asyncLSRTxShiftEmpty1 0x40
+#define asyncLSRRxFifoError1 0x80
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int uart_post_init (unsigned long dev_base)
+{
+ unsigned long reg;
+ unsigned long udiv;
+ unsigned short bdiv;
+ volatile char val;
+#ifdef CFG_EXT_SERIAL_CLOCK
+ unsigned long tmp;
+#endif
+ int i;
+
+ for (i = 0; i < 3500; i++) {
+ if (in8 (dev_base + UART_LSR) & asyncLSRTxHoldEmpty1)
+ break;
+ udelay (100);
+ }
+ MFREG(UART0_SDR, reg);
+ reg &= ~CR0_MASK;
+
+#ifdef CFG_EXT_SERIAL_CLOCK
+ reg |= CR0_EXTCLK_ENA;
+ udiv = 1;
+ tmp = gd->baudrate * 16;
+ bdiv = (CFG_EXT_SERIAL_CLOCK + tmp / 2) / tmp;
+#else
+ /* For 440, the cpu clock is on divider chain A, UART on divider
+ * chain B ... so cpu clock is irrelevant. Get the "optimized"
+ * values that are subject to the 1/2 opb clock constraint
+ */
+ serial_divs (gd->baudrate, &udiv, &bdiv);
+#endif
+
+ reg |= (udiv - UDIV_SUBTRACT) << CR0_UDIV_POS; /* set the UART divisor */
+
+ /*
+ * Configure input clock to baudrate generator for all
+ * available serial ports here
+ */
+ MTREG(UART0_SDR, reg);
+#if defined(UART1_SDR)
+ MTREG(UART1_SDR, reg);
+#endif
+#if defined(UART2_SDR)
+ MTREG(UART2_SDR, reg);
+#endif
+#if defined(UART3_SDR)
+ MTREG(UART3_SDR, reg);
+#endif
+
+ out8(dev_base + UART_LCR, 0x80); /* set DLAB bit */
+ out8(dev_base + UART_DLL, bdiv); /* set baudrate divisor */
+ out8(dev_base + UART_DLM, bdiv >> 8); /* set baudrate divisor */
+ out8(dev_base + UART_LCR, 0x03); /* clear DLAB; set 8 bits, no parity */
+ out8(dev_base + UART_FCR, 0x00); /* disable FIFO */
+ out8(dev_base + UART_MCR, 0x10); /* enable loopback mode */
+ val = in8(dev_base + UART_LSR); /* clear line status */
+ val = in8(dev_base + UART_RBR); /* read receive buffer */
+ out8(dev_base + UART_SCR, 0x00); /* set scratchpad */
+ out8(dev_base + UART_IER, 0x00); /* set interrupt enable reg */
+
+ return 0;
+}
+
+static void uart_post_putc (unsigned long dev_base, char c)
+{
+ int i;
+
+ out8 (dev_base + UART_THR, c); /* put character out */
+
+ /* Wait for transfer completion */
+ for (i = 0; i < 3500; i++) {
+ if (in8 (dev_base + UART_LSR) & asyncLSRTxHoldEmpty1)
+ break;
+ udelay (100);
+ }
+}
+
+static int uart_post_getc (unsigned long dev_base)
+{
+ int i;
+
+ /* Wait for character available */
+ for (i = 0; i < 3500; i++) {
+ if (in8 (dev_base + UART_LSR) & asyncLSRDataReady1)
+ break;
+ udelay (100);
+ }
+ return 0xff & in8 (dev_base + UART_RBR);
+}
+
+static int test_ctlr (unsigned long dev_base, int index)
+{
+ int res = -1;
+ char test_str[] = "*** UART Test String ***\r\n";
+ int i;
+
+ uart_post_init (dev_base);
+
+ for (i = 0; i < sizeof (test_str) - 1; i++) {
+ uart_post_putc (dev_base, test_str[i]);
+ if (uart_post_getc (dev_base) != test_str[i])
+ goto done;
+ }
+ res = 0;
+done:
+ if (res)
+ post_log ("uart%d test failed\n", index);
+
+ return res;
+}
+
+int uart_post_test (int flags)
+{
+ int i, res = 0;
+ static unsigned long base[] = {
+ UART0_BASE, UART1_BASE, UART2_BASE, UART3_BASE
+ };
+
+ for (i = 0; i < sizeof (base) / sizeof (base[0]); i++) {
+ if (test_ctlr (base[i], i))
+ res = -1;
+ }
+ serial_reinit_all ();
+
+ return res;
+}
+
+#endif /* CONFIG_POST & CFG_POST_UART */
+#endif /* CONFIG_POST */