Blame view

arch/tile/gxio/uart.c 2.01 KB
6ec006ede   Chris Metcalf   tilegx: provide k...
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
  /*
   * 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.
   */
  
  /*
   * Implementation of UART gxio calls.
   */
  
  #include <linux/io.h>
  #include <linux/errno.h>
  #include <linux/module.h>
  
  #include <gxio/uart.h>
  #include <gxio/iorpc_globals.h>
  #include <gxio/iorpc_uart.h>
  #include <gxio/kiorpc.h>
  
  int gxio_uart_init(gxio_uart_context_t *context, int uart_index)
  {
  	char file[32];
  	int fd;
  
  	snprintf(file, sizeof(file), "uart/%d/iorpc", uart_index);
  	fd = hv_dev_open((HV_VirtAddr) file, 0);
  	if (fd < 0) {
  		if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
  			return fd;
  		else
  			return -ENODEV;
  	}
  
  	context->fd = fd;
  
  	/* Map in the MMIO space. */
  	context->mmio_base = (void __force *)
  		iorpc_ioremap(fd, HV_UART_MMIO_OFFSET, HV_UART_MMIO_SIZE);
  
  	if (context->mmio_base == NULL) {
  		hv_dev_close(context->fd);
  		context->fd = -1;
  		return -ENODEV;
  	}
  
  	return 0;
  }
  
  EXPORT_SYMBOL_GPL(gxio_uart_init);
  
  int gxio_uart_destroy(gxio_uart_context_t *context)
  {
  	iounmap((void __force __iomem *)(context->mmio_base));
  	hv_dev_close(context->fd);
  
  	context->mmio_base = NULL;
  	context->fd = -1;
  
  	return 0;
  }
  
  EXPORT_SYMBOL_GPL(gxio_uart_destroy);
  
  /* UART register write wrapper. */
  void gxio_uart_write(gxio_uart_context_t *context, uint64_t offset,
  		     uint64_t word)
  {
  	__gxio_mmio_write(context->mmio_base + offset, word);
  }
  
  EXPORT_SYMBOL_GPL(gxio_uart_write);
  
  /* UART register read wrapper. */
  uint64_t gxio_uart_read(gxio_uart_context_t *context, uint64_t offset)
  {
  	return __gxio_mmio_read(context->mmio_base + offset);
  }
  
  EXPORT_SYMBOL_GPL(gxio_uart_read);