1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * Contains routines needed to support swiotlb for ppc.
 4 *
 5 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
 6 * Author: Becky Bruce
 
 
 
 
 
 
 7 */
 8#include <linux/memblock.h>
 
 
 
 
 
 
 9#include <asm/machdep.h>
10#include <asm/swiotlb.h>
 
 
11
12unsigned int ppc_swiotlb_enable;
13
14void __init swiotlb_detect_4g(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
15{
16	if ((memblock_end_of_DRAM() - 1) > 0xffffffff)
17		ppc_swiotlb_enable = 1;
 
 
 
 
 
18}
19
20static int __init check_swiotlb_enabled(void)
 
21{
22	if (ppc_swiotlb_enable)
23		swiotlb_print_info();
24	else
25		swiotlb_exit();
26
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
27	return 0;
28}
29subsys_initcall(check_swiotlb_enabled);

 
 1/*
 2 * Contains routines needed to support swiotlb for ppc.
 3 *
 4 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
 5 * Author: Becky Bruce
 6 *
 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.
11 *
12 */
13
14#include <linux/dma-mapping.h>
15#include <linux/pfn.h>
16#include <linux/of_platform.h>
17#include <linux/platform_device.h>
18#include <linux/pci.h>
19
20#include <asm/machdep.h>
21#include <asm/swiotlb.h>
22#include <asm/dma.h>
23#include <asm/abs_addr.h>
24
25unsigned int ppc_swiotlb_enable;
26
27/*
28 * At the moment, all platforms that use this code only require
29 * swiotlb to be used if we're operating on HIGHMEM.  Since
30 * we don't ever call anything other than map_sg, unmap_sg,
31 * map_page, and unmap_page on highmem, use normal dma_ops
32 * for everything else.
33 */
34struct dma_map_ops swiotlb_dma_ops = {
35	.alloc_coherent = dma_direct_alloc_coherent,
36	.free_coherent = dma_direct_free_coherent,
37	.map_sg = swiotlb_map_sg_attrs,
38	.unmap_sg = swiotlb_unmap_sg_attrs,
39	.dma_supported = swiotlb_dma_supported,
40	.map_page = swiotlb_map_page,
41	.unmap_page = swiotlb_unmap_page,
42	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
43	.sync_single_for_device = swiotlb_sync_single_for_device,
44	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
45	.sync_sg_for_device = swiotlb_sync_sg_for_device,
46	.mapping_error = swiotlb_dma_mapping_error,
47};
48
49void pci_dma_dev_setup_swiotlb(struct pci_dev *pdev)
50{
51	struct pci_controller *hose;
52	struct dev_archdata *sd;
53
54	hose = pci_bus_to_host(pdev->bus);
55	sd = &pdev->dev.archdata;
56	sd->max_direct_dma_addr =
57		hose->dma_window_base_cur + hose->dma_window_size;
58}
59
60static int ppc_swiotlb_bus_notify(struct notifier_block *nb,
61				  unsigned long action, void *data)
62{
63	struct device *dev = data;
64	struct dev_archdata *sd;
 
 
65
66	/* We are only intereted in device addition */
67	if (action != BUS_NOTIFY_ADD_DEVICE)
68		return 0;
69
70	sd = &dev->archdata;
71	sd->max_direct_dma_addr = 0;
72
73	/* May need to bounce if the device can't address all of DRAM */
74	if ((dma_get_mask(dev) + 1) < memblock_end_of_DRAM())
75		set_dma_ops(dev, &swiotlb_dma_ops);
76
77	return NOTIFY_DONE;
78}
79
80static struct notifier_block ppc_swiotlb_plat_bus_notifier = {
81	.notifier_call = ppc_swiotlb_bus_notify,
82	.priority = 0,
83};
84
85int __init swiotlb_setup_bus_notifier(void)
86{
87	bus_register_notifier(&platform_bus_type,
88			      &ppc_swiotlb_plat_bus_notifier);
89	return 0;
90}