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 /*
16 * Implementation of UART gxio calls.
17 */
18
19 #include <linux/io.h>
20 #include <linux/errno.h>
21 #include <linux/module.h>
22
23 #include <gxio/uart.h>
24 #include <gxio/iorpc_globals.h>
25 #include <gxio/iorpc_uart.h>
26 #include <gxio/kiorpc.h>
27
gxio_uart_init(gxio_uart_context_t * context,int uart_index)28 int gxio_uart_init(gxio_uart_context_t *context, int uart_index)
29 {
30 char file[32];
31 int fd;
32
33 snprintf(file, sizeof(file), "uart/%d/iorpc", uart_index);
34 fd = hv_dev_open((HV_VirtAddr) file, 0);
35 if (fd < 0) {
36 if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
37 return fd;
38 else
39 return -ENODEV;
40 }
41
42 context->fd = fd;
43
44 /* Map in the MMIO space. */
45 context->mmio_base = (void __force *)
46 iorpc_ioremap(fd, HV_UART_MMIO_OFFSET, HV_UART_MMIO_SIZE);
47
48 if (context->mmio_base == NULL) {
49 hv_dev_close(context->fd);
50 context->fd = -1;
51 return -ENODEV;
52 }
53
54 return 0;
55 }
56
57 EXPORT_SYMBOL_GPL(gxio_uart_init);
58
gxio_uart_destroy(gxio_uart_context_t * context)59 int gxio_uart_destroy(gxio_uart_context_t *context)
60 {
61 iounmap((void __force __iomem *)(context->mmio_base));
62 hv_dev_close(context->fd);
63
64 context->mmio_base = NULL;
65 context->fd = -1;
66
67 return 0;
68 }
69
70 EXPORT_SYMBOL_GPL(gxio_uart_destroy);
71
72 /* UART register write wrapper. */
gxio_uart_write(gxio_uart_context_t * context,uint64_t offset,uint64_t word)73 void gxio_uart_write(gxio_uart_context_t *context, uint64_t offset,
74 uint64_t word)
75 {
76 __gxio_mmio_write(context->mmio_base + offset, word);
77 }
78
79 EXPORT_SYMBOL_GPL(gxio_uart_write);
80
81 /* UART register read wrapper. */
gxio_uart_read(gxio_uart_context_t * context,uint64_t offset)82 uint64_t gxio_uart_read(gxio_uart_context_t *context, uint64_t offset)
83 {
84 return __gxio_mmio_read(context->mmio_base + offset);
85 }
86
87 EXPORT_SYMBOL_GPL(gxio_uart_read);
88