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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
|
/*
* Contains routines needed to support swiotlb for ppc.
*
* Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
* Author: Becky Bruce
*
* 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; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include <linux/dma-direct.h>
#include <linux/memblock.h>
#include <linux/pfn.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <asm/machdep.h>
#include <asm/swiotlb.h>
#include <asm/dma.h>
unsigned int ppc_swiotlb_enable;
static u64 swiotlb_powerpc_get_required(struct device *dev)
{
u64 end, mask, max_direct_dma_addr = dev->archdata.max_direct_dma_addr;
end = memblock_end_of_DRAM();
if (max_direct_dma_addr && end > max_direct_dma_addr)
end = max_direct_dma_addr;
end += get_dma_offset(dev);
mask = 1ULL << (fls64(end) - 1);
mask += mask - 1;
return mask;
}
/*
* At the moment, all platforms that use this code only require
* swiotlb to be used if we're operating on HIGHMEM. Since
* we don't ever call anything other than map_sg, unmap_sg,
* map_page, and unmap_page on highmem, use normal dma_ops
* for everything else.
*/
const struct dma_map_ops powerpc_swiotlb_dma_ops = {
.alloc = __dma_nommu_alloc_coherent,
.free = __dma_nommu_free_coherent,
.mmap = dma_nommu_mmap_coherent,
.map_sg = dma_direct_map_sg,
.unmap_sg = dma_direct_unmap_sg,
.dma_supported = swiotlb_dma_supported,
.map_page = dma_direct_map_page,
.unmap_page = dma_direct_unmap_page,
.sync_single_for_cpu = dma_direct_sync_single_for_cpu,
.sync_single_for_device = dma_direct_sync_single_for_device,
.sync_sg_for_cpu = dma_direct_sync_sg_for_cpu,
.sync_sg_for_device = dma_direct_sync_sg_for_device,
.get_required_mask = swiotlb_powerpc_get_required,
};
static int ppc_swiotlb_bus_notify(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
struct dev_archdata *sd;
/* We are only intereted in device addition */
if (action != BUS_NOTIFY_ADD_DEVICE)
return 0;
sd = &dev->archdata;
sd->max_direct_dma_addr = 0;
/* May need to bounce if the device can't address all of DRAM */
if ((dma_get_mask(dev) + 1) < memblock_end_of_DRAM())
set_dma_ops(dev, &powerpc_swiotlb_dma_ops);
return NOTIFY_DONE;
}
static struct notifier_block ppc_swiotlb_plat_bus_notifier = {
.notifier_call = ppc_swiotlb_bus_notify,
.priority = 0,
};
int __init swiotlb_setup_bus_notifier(void)
{
bus_register_notifier(&platform_bus_type,
&ppc_swiotlb_plat_bus_notifier);
return 0;
}
void __init swiotlb_detect_4g(void)
{
if ((memblock_end_of_DRAM() - 1) > 0xffffffff)
ppc_swiotlb_enable = 1;
}
static int __init check_swiotlb_enabled(void)
{
if (ppc_swiotlb_enable)
swiotlb_print_info();
else
swiotlb_exit();
return 0;
}
subsys_initcall(check_swiotlb_enabled);
|
