2 * Contains routines needed to support swiotlb for ppc.
4 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
14 #include <linux/dma-mapping.h>
15 #include <linux/memblock.h>
16 #include <linux/pfn.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
19 #include <linux/pci.h>
21 #include <asm/machdep.h>
22 #include <asm/swiotlb.h>
25 unsigned int ppc_swiotlb_enable
;
27 static u64
swiotlb_powerpc_get_required(struct device
*dev
)
29 u64 end
, mask
, max_direct_dma_addr
= dev
->archdata
.max_direct_dma_addr
;
31 end
= memblock_end_of_DRAM();
32 if (max_direct_dma_addr
&& end
> max_direct_dma_addr
)
33 end
= max_direct_dma_addr
;
34 end
+= get_dma_offset(dev
);
36 mask
= 1ULL << (fls64(end
) - 1);
43 * At the moment, all platforms that use this code only require
44 * swiotlb to be used if we're operating on HIGHMEM. Since
45 * we don't ever call anything other than map_sg, unmap_sg,
46 * map_page, and unmap_page on highmem, use normal dma_ops
47 * for everything else.
49 struct dma_map_ops swiotlb_dma_ops
= {
50 .alloc
= __dma_direct_alloc_coherent
,
51 .free
= __dma_direct_free_coherent
,
52 .mmap
= dma_direct_mmap_coherent
,
53 .map_sg
= swiotlb_map_sg_attrs
,
54 .unmap_sg
= swiotlb_unmap_sg_attrs
,
55 .dma_supported
= swiotlb_dma_supported
,
56 .map_page
= swiotlb_map_page
,
57 .unmap_page
= swiotlb_unmap_page
,
58 .sync_single_for_cpu
= swiotlb_sync_single_for_cpu
,
59 .sync_single_for_device
= swiotlb_sync_single_for_device
,
60 .sync_sg_for_cpu
= swiotlb_sync_sg_for_cpu
,
61 .sync_sg_for_device
= swiotlb_sync_sg_for_device
,
62 .mapping_error
= swiotlb_dma_mapping_error
,
63 .get_required_mask
= swiotlb_powerpc_get_required
,
66 void pci_dma_dev_setup_swiotlb(struct pci_dev
*pdev
)
68 struct pci_controller
*hose
;
69 struct dev_archdata
*sd
;
71 hose
= pci_bus_to_host(pdev
->bus
);
72 sd
= &pdev
->dev
.archdata
;
73 sd
->max_direct_dma_addr
=
74 hose
->dma_window_base_cur
+ hose
->dma_window_size
;
77 static int ppc_swiotlb_bus_notify(struct notifier_block
*nb
,
78 unsigned long action
, void *data
)
80 struct device
*dev
= data
;
81 struct dev_archdata
*sd
;
83 /* We are only intereted in device addition */
84 if (action
!= BUS_NOTIFY_ADD_DEVICE
)
88 sd
->max_direct_dma_addr
= 0;
90 /* May need to bounce if the device can't address all of DRAM */
91 if ((dma_get_mask(dev
) + 1) < memblock_end_of_DRAM())
92 set_dma_ops(dev
, &swiotlb_dma_ops
);
97 static struct notifier_block ppc_swiotlb_plat_bus_notifier
= {
98 .notifier_call
= ppc_swiotlb_bus_notify
,
102 int __init
swiotlb_setup_bus_notifier(void)
104 bus_register_notifier(&platform_bus_type
,
105 &ppc_swiotlb_plat_bus_notifier
);
109 void __init
swiotlb_detect_4g(void)
111 if ((memblock_end_of_DRAM() - 1) > 0xffffffff) {
112 ppc_swiotlb_enable
= 1;
113 #ifdef CONFIG_ZONE_DMA32
114 limit_zone_pfn(ZONE_DMA32
, (1ULL << 32) >> PAGE_SHIFT
);
119 static int __init
check_swiotlb_enabled(void)
121 if (ppc_swiotlb_enable
)
122 swiotlb_print_info();
128 subsys_initcall(check_swiotlb_enabled
);