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-rw-r--r--arch/blackfin/cpu/serial.c193
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diff --git a/arch/blackfin/cpu/serial.c b/arch/blackfin/cpu/serial.c
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+/*
+ * U-boot - serial.c Blackfin Serial Driver
+ *
+ * Copyright (c) 2005-2008 Analog Devices Inc.
+ *
+ * Copyright (c) 2003 Bas Vermeulen <bas@buyways.nl>,
+ * BuyWays B.V. (www.buyways.nl)
+ *
+ * Based heavily on:
+ * blkfinserial.c: Serial driver for BlackFin DSP internal USRTs.
+ * Copyright(c) 2003 Metrowerks <mwaddel@metrowerks.com>
+ * Copyright(c) 2001 Tony Z. Kou <tonyko@arcturusnetworks.com>
+ * Copyright(c) 2001-2002 Arcturus Networks Inc. <www.arcturusnetworks.com>
+ *
+ * Based on code from 68328 version serial driver imlpementation which was:
+ * Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu>
+ * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
+ * Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org>
+ * Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com>
+ *
+ * (C) Copyright 2000-2004
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+/* Anomaly notes:
+ * 05000086 - we don't support autobaud
+ * 05000099 - we only use DR bit, so losing others is not a problem
+ * 05000100 - we don't use the UART_IIR register
+ * 05000215 - we poll the uart (no dma/interrupts)
+ * 05000225 - no workaround possible, but this shouldnt cause errors ...
+ * 05000230 - we tweak the baud rate calculation slightly
+ * 05000231 - we always use 1 stop bit
+ * 05000309 - we always enable the uart before we modify it in anyway
+ * 05000350 - we always enable the uart regardless of boot mode
+ * 05000363 - we don't support break signals, so don't generate one
+ */
+
+#include <common.h>
+#include <watchdog.h>
+#include <asm/blackfin.h>
+#include <asm/mach-common/bits/uart.h>
+
+#ifdef CONFIG_UART_CONSOLE
+
+#include "serial.h"
+
+#ifdef CONFIG_DEBUG_SERIAL
+uint16_t cached_lsr[256];
+uint16_t cached_rbr[256];
+size_t cache_count;
+
+/* The LSR is read-to-clear on some parts, so we have to make sure status
+ * bits aren't inadvertently lost when doing various tests. This also
+ * works around anomaly 05000099 at the same time by keeping a cumulative
+ * tally of all the status bits.
+ */
+static uint16_t uart_lsr_save;
+static uint16_t uart_lsr_read(void)
+{
+ uint16_t lsr = bfin_read16(&pUART->lsr);
+ uart_lsr_save |= (lsr & (OE|PE|FE|BI));
+ return lsr | uart_lsr_save;
+}
+/* Just do the clear for everyone since it can't hurt. */
+static void uart_lsr_clear(void)
+{
+ uart_lsr_save = 0;
+ bfin_write16(&pUART->lsr, bfin_read16(&pUART->lsr) | -1);
+}
+#else
+/* When debugging is disabled, we only care about the DR bit, so if other
+ * bits get set/cleared, we don't really care since we don't read them
+ * anyways (and thus anomaly 05000099 is irrelevant).
+ */
+static uint16_t uart_lsr_read(void)
+{
+ return bfin_read16(&pUART->lsr);
+}
+static void uart_lsr_clear(void)
+{
+ bfin_write16(&pUART->lsr, bfin_read16(&pUART->lsr) | -1);
+}
+#endif
+
+/* Symbol for our assembly to call. */
+void serial_set_baud(uint32_t baud)
+{
+ serial_early_set_baud(baud);
+}
+
+/* Symbol for common u-boot code to call.
+ * Setup the baudrate (brg: baudrate generator).
+ */
+void serial_setbrg(void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ serial_set_baud(gd->baudrate);
+}
+
+/* Symbol for our assembly to call. */
+void serial_initialize(void)
+{
+ serial_early_init();
+}
+
+/* Symbol for common u-boot code to call. */
+int serial_init(void)
+{
+ serial_initialize();
+ serial_setbrg();
+ uart_lsr_clear();
+#ifdef CONFIG_DEBUG_SERIAL
+ cache_count = 0;
+ memset(cached_lsr, 0x00, sizeof(cached_lsr));
+ memset(cached_rbr, 0x00, sizeof(cached_rbr));
+#endif
+ return 0;
+}
+
+void serial_putc(const char c)
+{
+ /* send a \r for compatibility */
+ if (c == '\n')
+ serial_putc('\r');
+
+ WATCHDOG_RESET();
+
+ /* wait for the hardware fifo to clear up */
+ while (!(uart_lsr_read() & THRE))
+ continue;
+
+ /* queue the character for transmission */
+ bfin_write16(&pUART->thr, c);
+ SSYNC();
+
+ WATCHDOG_RESET();
+}
+
+int serial_tstc(void)
+{
+ WATCHDOG_RESET();
+ return (uart_lsr_read() & DR) ? 1 : 0;
+}
+
+int serial_getc(void)
+{
+ uint16_t uart_rbr_val;
+
+ /* wait for data ! */
+ while (!serial_tstc())
+ continue;
+
+ /* grab the new byte */
+ uart_rbr_val = bfin_read16(&pUART->rbr);
+
+#ifdef CONFIG_DEBUG_SERIAL
+ /* grab & clear the LSR */
+ uint16_t uart_lsr_val = uart_lsr_read();
+
+ cached_lsr[cache_count] = uart_lsr_val;
+ cached_rbr[cache_count] = uart_rbr_val;
+ cache_count = (cache_count + 1) % ARRAY_SIZE(cached_lsr);
+
+ if (uart_lsr_val & (OE|PE|FE|BI)) {
+ uint16_t dll, dlh;
+ printf("\n[SERIAL ERROR]\n");
+ ACCESS_LATCH();
+ dll = bfin_read16(&pUART->dll);
+ dlh = bfin_read16(&pUART->dlh);
+ ACCESS_PORT_IER();
+ printf("\tDLL=0x%x DLH=0x%x\n", dll, dlh);
+ do {
+ --cache_count;
+ printf("\t%3i: RBR=0x%02x LSR=0x%02x\n", cache_count,
+ cached_rbr[cache_count], cached_lsr[cache_count]);
+ } while (cache_count > 0);
+ return -1;
+ }
+#endif
+ uart_lsr_clear();
+
+ return uart_rbr_val;
+}
+
+void serial_puts(const char *s)
+{
+ while (*s)
+ serial_putc(*s++);
+}
+
+#endif