linux/arch/powerpc/kernel/dma-swiotlb.c
Linus Torvalds af7ddd8a62 DMA mapping updates for Linux 4.21
A huge update this time, but a lot of that is just consolidating or
 removing code:
 
  - provide a common DMA_MAPPING_ERROR definition and avoid indirect
    calls for dma_map_* error checking
  - use direct calls for the DMA direct mapping case, avoiding huge
    retpoline overhead for high performance workloads
  - merge the swiotlb dma_map_ops into dma-direct
  - provide a generic remapping DMA consistent allocator for architectures
    that have devices that perform DMA that is not cache coherent. Based
    on the existing arm64 implementation and also used for csky now.
  - improve the dma-debug infrastructure, including dynamic allocation
    of entries (Robin Murphy)
  - default to providing chaining scatterlist everywhere, with opt-outs
    for the few architectures (alpha, parisc, most arm32 variants) that
    can't cope with it
  - misc sparc32 dma-related cleanups
  - remove the dma_mark_clean arch hook used by swiotlb on ia64 and
    replace it with the generic noncoherent infrastructure
  - fix the return type of dma_set_max_seg_size (Niklas Söderlund)
  - move the dummy dma ops for not DMA capable devices from arm64 to
    common code (Robin Murphy)
  - ensure dma_alloc_coherent returns zeroed memory to avoid kernel data
    leaks through userspace.  We already did this for most common
    architectures, but this ensures we do it everywhere.
    dma_zalloc_coherent has been deprecated and can hopefully be
    removed after -rc1 with a coccinelle script.
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Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping

Pull DMA mapping updates from Christoph Hellwig:
 "A huge update this time, but a lot of that is just consolidating or
  removing code:

   - provide a common DMA_MAPPING_ERROR definition and avoid indirect
     calls for dma_map_* error checking

   - use direct calls for the DMA direct mapping case, avoiding huge
     retpoline overhead for high performance workloads

   - merge the swiotlb dma_map_ops into dma-direct

   - provide a generic remapping DMA consistent allocator for
     architectures that have devices that perform DMA that is not cache
     coherent. Based on the existing arm64 implementation and also used
     for csky now.

   - improve the dma-debug infrastructure, including dynamic allocation
     of entries (Robin Murphy)

   - default to providing chaining scatterlist everywhere, with opt-outs
     for the few architectures (alpha, parisc, most arm32 variants) that
     can't cope with it

   - misc sparc32 dma-related cleanups

   - remove the dma_mark_clean arch hook used by swiotlb on ia64 and
     replace it with the generic noncoherent infrastructure

   - fix the return type of dma_set_max_seg_size (Niklas Söderlund)

   - move the dummy dma ops for not DMA capable devices from arm64 to
     common code (Robin Murphy)

   - ensure dma_alloc_coherent returns zeroed memory to avoid kernel
     data leaks through userspace. We already did this for most common
     architectures, but this ensures we do it everywhere.
     dma_zalloc_coherent has been deprecated and can hopefully be
     removed after -rc1 with a coccinelle script"

* tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping: (73 commits)
  dma-mapping: fix inverted logic in dma_supported
  dma-mapping: deprecate dma_zalloc_coherent
  dma-mapping: zero memory returned from dma_alloc_*
  sparc/iommu: fix ->map_sg return value
  sparc/io-unit: fix ->map_sg return value
  arm64: default to the direct mapping in get_arch_dma_ops
  PCI: Remove unused attr variable in pci_dma_configure
  ia64: only select ARCH_HAS_DMA_COHERENT_TO_PFN if swiotlb is enabled
  dma-mapping: bypass indirect calls for dma-direct
  vmd: use the proper dma_* APIs instead of direct methods calls
  dma-direct: merge swiotlb_dma_ops into the dma_direct code
  dma-direct: use dma_direct_map_page to implement dma_direct_map_sg
  dma-direct: improve addressability error reporting
  swiotlb: remove dma_mark_clean
  swiotlb: remove SWIOTLB_MAP_ERROR
  ACPI / scan: Refactor _CCA enforcement
  dma-mapping: factor out dummy DMA ops
  dma-mapping: always build the direct mapping code
  dma-mapping: move dma_cache_sync out of line
  dma-mapping: move various slow path functions out of line
  ...
2018-12-28 14:12:21 -08:00

124 lines
3.2 KiB
C

/*
* 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,
};
void pci_dma_dev_setup_swiotlb(struct pci_dev *pdev)
{
struct pci_controller *hose;
struct dev_archdata *sd;
hose = pci_bus_to_host(pdev->bus);
sd = &pdev->dev.archdata;
sd->max_direct_dma_addr =
hose->dma_window_base_cur + hose->dma_window_size;
}
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);