1 /*
2 * Copyright 2012 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 * TILE-Gx IORPC support for kernel I/O drivers.
15 */
16
17 #include <linux/mmzone.h>
18 #include <linux/module.h>
19 #include <linux/io.h>
20 #include <gxio/iorpc_globals.h>
21 #include <gxio/kiorpc.h>
22
23 #ifdef DEBUG_IORPC
24 #define TRACE(FMT, ...) pr_info(SIMPLE_MSG_LINE FMT, ## __VA_ARGS__)
25 #else
26 #define TRACE(...)
27 #endif
28
29 /* Create kernel-VA-space MMIO mapping for an on-chip IO device. */
iorpc_ioremap(int hv_fd,resource_size_t offset,unsigned long size)30 void __iomem *iorpc_ioremap(int hv_fd, resource_size_t offset,
31 unsigned long size)
32 {
33 pgprot_t mmio_base, prot = { 0 };
34 unsigned long pfn;
35 int err;
36
37 /* Look up the shim's lotar and base PA. */
38 err = __iorpc_get_mmio_base(hv_fd, &mmio_base);
39 if (err) {
40 TRACE("get_mmio_base() failure: %d\n", err);
41 return NULL;
42 }
43
44 /* Make sure the HV driver approves of our offset and size. */
45 err = __iorpc_check_mmio_offset(hv_fd, offset, size);
46 if (err) {
47 TRACE("check_mmio_offset() failure: %d\n", err);
48 return NULL;
49 }
50
51 /*
52 * mmio_base contains a base pfn and homing coordinates. Turn
53 * it into an MMIO pgprot and offset pfn.
54 */
55 prot = hv_pte_set_lotar(prot, hv_pte_get_lotar(mmio_base));
56 pfn = pte_pfn(mmio_base) + PFN_DOWN(offset);
57
58 return ioremap_prot(PFN_PHYS(pfn), size, prot);
59 }
60
61 EXPORT_SYMBOL(iorpc_ioremap);
62