/*
* 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-mapping.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 swiotlb_dma_ops = {
.alloc = __dma_direct_alloc_coherent,
.free = __dma_direct_free_coherent,
.mmap = dma_direct_mmap_coherent,
.map_sg = swiotlb_map_sg_attrs,
.unmap_sg = swiotlb_unmap_sg_attrs,
.dma_supported = swiotlb_dma_supported,
.map_page = swiotlb_map_page,
.unmap_page = swiotlb_unmap_page,
.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
.sync_single_for_device = swiotlb_sync_single_for_device,
.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = swiotlb_sync_sg_for_device,
.mapping_error = swiotlb_dma_mapping_error,
.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, &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;
#ifdef CONFIG_ZONE_DMA32
limit_zone_pfn(ZONE_DMA32, (1ULL << 32) >> PAGE_SHIFT);
#endif
}
}
static int __init check_swiotlb_enabled(void)
{
if (ppc_swiotlb_enable)
swiotlb_print_info();
else
swiotlb_free();
return 0;
}
subsys_initcall(check_swiotlb_enabled);
