/* * 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);