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Diffstat (limited to 'arch/tile/include/gxio/uart.h')
-rw-r--r-- | arch/tile/include/gxio/uart.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/tile/include/gxio/uart.h b/arch/tile/include/gxio/uart.h new file mode 100644 index 000000000..438ee7e46 --- /dev/null +++ b/arch/tile/include/gxio/uart.h @@ -0,0 +1,105 @@ +/* + * 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_ */ |