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-rw-r--r--arch/powerpc/boot/uartlite.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/powerpc/boot/uartlite.c b/arch/powerpc/boot/uartlite.c
new file mode 100644
index 000000000..46bed69b4
--- /dev/null
+++ b/arch/powerpc/boot/uartlite.c
@@ -0,0 +1,79 @@
+/*
+ * Xilinx UARTLITE bootloader driver
+ *
+ * Copyright (C) 2007 Secret Lab Technologies Ltd.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "string.h"
+#include "stdio.h"
+#include "io.h"
+#include "ops.h"
+
+#define ULITE_RX 0x00
+#define ULITE_TX 0x04
+#define ULITE_STATUS 0x08
+#define ULITE_CONTROL 0x0c
+
+#define ULITE_STATUS_RXVALID 0x01
+#define ULITE_STATUS_TXFULL 0x08
+
+#define ULITE_CONTROL_RST_RX 0x02
+
+static void * reg_base;
+
+static int uartlite_open(void)
+{
+ /* Clear the RX FIFO */
+ out_be32(reg_base + ULITE_CONTROL, ULITE_CONTROL_RST_RX);
+ return 0;
+}
+
+static void uartlite_putc(unsigned char c)
+{
+ u32 reg = ULITE_STATUS_TXFULL;
+ while (reg & ULITE_STATUS_TXFULL) /* spin on TXFULL bit */
+ reg = in_be32(reg_base + ULITE_STATUS);
+ out_be32(reg_base + ULITE_TX, c);
+}
+
+static unsigned char uartlite_getc(void)
+{
+ u32 reg = 0;
+ while (!(reg & ULITE_STATUS_RXVALID)) /* spin waiting for RXVALID bit */
+ reg = in_be32(reg_base + ULITE_STATUS);
+ return in_be32(reg_base + ULITE_RX);
+}
+
+static u8 uartlite_tstc(void)
+{
+ u32 reg = in_be32(reg_base + ULITE_STATUS);
+ return reg & ULITE_STATUS_RXVALID;
+}
+
+int uartlite_console_init(void *devp, struct serial_console_data *scdp)
+{
+ int n;
+ unsigned long reg_phys;
+
+ n = getprop(devp, "virtual-reg", &reg_base, sizeof(reg_base));
+ if (n != sizeof(reg_base)) {
+ if (!dt_xlate_reg(devp, 0, &reg_phys, NULL))
+ return -1;
+
+ reg_base = (void *)reg_phys;
+ }
+
+ scdp->open = uartlite_open;
+ scdp->putc = uartlite_putc;
+ scdp->getc = uartlite_getc;
+ scdp->tstc = uartlite_tstc;
+ scdp->close = NULL;
+ return 0;
+}