Chris Metcalf | 6ec006e | 2013-08-12 14:09:28 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2013 Tilera Corporation. All Rights Reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation, version 2. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but |
| 9 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 11 | * NON INFRINGEMENT. See the GNU General Public License for |
| 12 | * more details. |
| 13 | */ |
| 14 | |
| 15 | #ifndef _GXIO_UART_H_ |
| 16 | #define _GXIO_UART_H_ |
| 17 | |
| 18 | #include "common.h" |
| 19 | |
| 20 | #include <hv/drv_uart_intf.h> |
| 21 | #include <hv/iorpc.h> |
| 22 | |
| 23 | /* |
| 24 | * |
| 25 | * An API for manipulating UART interface. |
| 26 | */ |
| 27 | |
| 28 | /* |
| 29 | * |
| 30 | * The Rshim allows access to the processor's UART interface. |
| 31 | */ |
| 32 | |
| 33 | /* A context object used to manage UART resources. */ |
| 34 | typedef struct { |
| 35 | |
| 36 | /* File descriptor for calling up to the hypervisor. */ |
| 37 | int fd; |
| 38 | |
| 39 | /* The VA at which our MMIO registers are mapped. */ |
| 40 | char *mmio_base; |
| 41 | |
| 42 | } gxio_uart_context_t; |
| 43 | |
| 44 | /* Request UART interrupts. |
| 45 | * |
| 46 | * Request that interrupts be delivered to a tile when the UART's |
| 47 | * Receive FIFO is written, or the Write FIFO is read. |
| 48 | * |
| 49 | * @param context Pointer to a properly initialized gxio_uart_context_t. |
| 50 | * @param bind_cpu_x X coordinate of CPU to which interrupt will be delivered. |
| 51 | * @param bind_cpu_y Y coordinate of CPU to which interrupt will be delivered. |
| 52 | * @param bind_interrupt IPI interrupt number. |
| 53 | * @param bind_event Sub-interrupt event bit number; a negative value can |
| 54 | * disable the interrupt. |
| 55 | * @return Zero if all of the requested UART events were successfully |
| 56 | * configured to interrupt. |
| 57 | */ |
| 58 | extern int gxio_uart_cfg_interrupt(gxio_uart_context_t *context, |
| 59 | int bind_cpu_x, |
| 60 | int bind_cpu_y, |
| 61 | int bind_interrupt, int bind_event); |
| 62 | |
| 63 | /* Initialize a UART context. |
| 64 | * |
| 65 | * A properly initialized context must be obtained before any of the other |
| 66 | * gxio_uart routines may be used. |
| 67 | * |
| 68 | * @param context Pointer to a gxio_uart_context_t, which will be initialized |
| 69 | * by this routine, if it succeeds. |
| 70 | * @param uart_index Index of the UART to use. |
| 71 | * @return Zero if the context was successfully initialized, else a |
| 72 | * GXIO_ERR_xxx error code. |
| 73 | */ |
| 74 | extern int gxio_uart_init(gxio_uart_context_t *context, int uart_index); |
| 75 | |
| 76 | /* Destroy a UART context. |
| 77 | * |
| 78 | * Once destroyed, a context may not be used with any gxio_uart routines |
| 79 | * other than gxio_uart_init(). After this routine returns, no further |
| 80 | * interrupts requested on this context will be delivered. The state and |
| 81 | * configuration of the pins which had been attached to this context are |
| 82 | * unchanged by this operation. |
| 83 | * |
| 84 | * @param context Pointer to a gxio_uart_context_t. |
| 85 | * @return Zero if the context was successfully destroyed, else a |
| 86 | * GXIO_ERR_xxx error code. |
| 87 | */ |
| 88 | extern int gxio_uart_destroy(gxio_uart_context_t *context); |
| 89 | |
| 90 | /* Write UART register. |
| 91 | * @param context Pointer to a gxio_uart_context_t. |
| 92 | * @param offset UART register offset. |
| 93 | * @param word Data will be wrote to UART reigister. |
| 94 | */ |
| 95 | extern void gxio_uart_write(gxio_uart_context_t *context, uint64_t offset, |
| 96 | uint64_t word); |
| 97 | |
| 98 | /* Read UART register. |
| 99 | * @param context Pointer to a gxio_uart_context_t. |
| 100 | * @param offset UART register offset. |
| 101 | * @return Data read from UART register. |
| 102 | */ |
| 103 | extern uint64_t gxio_uart_read(gxio_uart_context_t *context, uint64_t offset); |
| 104 | |
| 105 | #endif /* _GXIO_UART_H_ */ |