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-rw-r--r--arch/tile/include/gxio/uart.h105
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/tile/include/gxio/uart.h b/arch/tile/include/gxio/uart.h
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+/*
+ * Copyright 2013 Tilera Corporation. All Rights Reserved.
+ *
+ * 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, version 2.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef _GXIO_UART_H_
+#define _GXIO_UART_H_
+
+#include "common.h"
+
+#include <hv/drv_uart_intf.h>
+#include <hv/iorpc.h>
+
+/*
+ *
+ * An API for manipulating UART interface.
+ */
+
+/*
+ *
+ * The Rshim allows access to the processor's UART interface.
+ */
+
+/* A context object used to manage UART resources. */
+typedef struct {
+
+ /* File descriptor for calling up to the hypervisor. */
+ int fd;
+
+ /* The VA at which our MMIO registers are mapped. */
+ char *mmio_base;
+
+} gxio_uart_context_t;
+
+/* Request UART interrupts.
+ *
+ * Request that interrupts be delivered to a tile when the UART's
+ * Receive FIFO is written, or the Write FIFO is read.
+ *
+ * @param context Pointer to a properly initialized gxio_uart_context_t.
+ * @param bind_cpu_x X coordinate of CPU to which interrupt will be delivered.
+ * @param bind_cpu_y Y coordinate of CPU to which interrupt will be delivered.
+ * @param bind_interrupt IPI interrupt number.
+ * @param bind_event Sub-interrupt event bit number; a negative value can
+ * disable the interrupt.
+ * @return Zero if all of the requested UART events were successfully
+ * configured to interrupt.
+ */
+extern int gxio_uart_cfg_interrupt(gxio_uart_context_t *context,
+ int bind_cpu_x,
+ int bind_cpu_y,
+ int bind_interrupt, int bind_event);
+
+/* Initialize a UART context.
+ *
+ * A properly initialized context must be obtained before any of the other
+ * gxio_uart routines may be used.
+ *
+ * @param context Pointer to a gxio_uart_context_t, which will be initialized
+ * by this routine, if it succeeds.
+ * @param uart_index Index of the UART to use.
+ * @return Zero if the context was successfully initialized, else a
+ * GXIO_ERR_xxx error code.
+ */
+extern int gxio_uart_init(gxio_uart_context_t *context, int uart_index);
+
+/* Destroy a UART context.
+ *
+ * Once destroyed, a context may not be used with any gxio_uart routines
+ * other than gxio_uart_init(). After this routine returns, no further
+ * interrupts requested on this context will be delivered. The state and
+ * configuration of the pins which had been attached to this context are
+ * unchanged by this operation.
+ *
+ * @param context Pointer to a gxio_uart_context_t.
+ * @return Zero if the context was successfully destroyed, else a
+ * GXIO_ERR_xxx error code.
+ */
+extern int gxio_uart_destroy(gxio_uart_context_t *context);
+
+/* Write UART register.
+ * @param context Pointer to a gxio_uart_context_t.
+ * @param offset UART register offset.
+ * @param word Data will be wrote to UART reigister.
+ */
+extern void gxio_uart_write(gxio_uart_context_t *context, uint64_t offset,
+ uint64_t word);
+
+/* Read UART register.
+ * @param context Pointer to a gxio_uart_context_t.
+ * @param offset UART register offset.
+ * @return Data read from UART register.
+ */
+extern uint64_t gxio_uart_read(gxio_uart_context_t *context, uint64_t offset);
+
+#endif /* _GXIO_UART_H_ */