1ec3cf2ecSBecky Bruce /* 2ec3cf2ecSBecky Bruce * Contains routines needed to support swiotlb for ppc. 3ec3cf2ecSBecky Bruce * 4ec3cf2ecSBecky Bruce * Copyright (C) 2009 Becky Bruce, Freescale Semiconductor 5ec3cf2ecSBecky Bruce * 6ec3cf2ecSBecky Bruce * This program is free software; you can redistribute it and/or modify it 7ec3cf2ecSBecky Bruce * under the terms of the GNU General Public License as published by the 8ec3cf2ecSBecky Bruce * Free Software Foundation; either version 2 of the License, or (at your 9ec3cf2ecSBecky Bruce * option) any later version. 10ec3cf2ecSBecky Bruce * 11ec3cf2ecSBecky Bruce */ 12ec3cf2ecSBecky Bruce 13ec3cf2ecSBecky Bruce #include <linux/dma-mapping.h> 14ec3cf2ecSBecky Bruce #include <linux/pfn.h> 15ec3cf2ecSBecky Bruce #include <linux/of_platform.h> 16ec3cf2ecSBecky Bruce #include <linux/platform_device.h> 17ec3cf2ecSBecky Bruce #include <linux/pci.h> 18ec3cf2ecSBecky Bruce 19ec3cf2ecSBecky Bruce #include <asm/machdep.h> 20ec3cf2ecSBecky Bruce #include <asm/swiotlb.h> 21ec3cf2ecSBecky Bruce #include <asm/dma.h> 22ec3cf2ecSBecky Bruce #include <asm/abs_addr.h> 23ec3cf2ecSBecky Bruce 24ec3cf2ecSBecky Bruce int swiotlb __read_mostly; 25ec3cf2ecSBecky Bruce unsigned int ppc_swiotlb_enable; 26ec3cf2ecSBecky Bruce 27ec3cf2ecSBecky Bruce void *swiotlb_bus_to_virt(struct device *hwdev, dma_addr_t addr) 28ec3cf2ecSBecky Bruce { 29ec3cf2ecSBecky Bruce unsigned long pfn = PFN_DOWN(swiotlb_bus_to_phys(hwdev, addr)); 30ec3cf2ecSBecky Bruce void *pageaddr = page_address(pfn_to_page(pfn)); 31ec3cf2ecSBecky Bruce 32ec3cf2ecSBecky Bruce if (pageaddr != NULL) 33ec3cf2ecSBecky Bruce return pageaddr + (addr % PAGE_SIZE); 34ec3cf2ecSBecky Bruce return NULL; 35ec3cf2ecSBecky Bruce } 36ec3cf2ecSBecky Bruce 37ec3cf2ecSBecky Bruce dma_addr_t swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr) 38ec3cf2ecSBecky Bruce { 39ec3cf2ecSBecky Bruce return paddr + get_dma_direct_offset(hwdev); 40ec3cf2ecSBecky Bruce } 41ec3cf2ecSBecky Bruce 42ec3cf2ecSBecky Bruce phys_addr_t swiotlb_bus_to_phys(struct device *hwdev, dma_addr_t baddr) 43ec3cf2ecSBecky Bruce 44ec3cf2ecSBecky Bruce { 45ec3cf2ecSBecky Bruce return baddr - get_dma_direct_offset(hwdev); 46ec3cf2ecSBecky Bruce } 47ec3cf2ecSBecky Bruce 48ec3cf2ecSBecky Bruce /* 49ec3cf2ecSBecky Bruce * Determine if an address needs bounce buffering via swiotlb. 50ec3cf2ecSBecky Bruce * Going forward I expect the swiotlb code to generalize on using 51ec3cf2ecSBecky Bruce * a dma_ops->addr_needs_map, and this function will move from here to the 52ec3cf2ecSBecky Bruce * generic swiotlb code. 53ec3cf2ecSBecky Bruce */ 54ec3cf2ecSBecky Bruce int 55ec3cf2ecSBecky Bruce swiotlb_arch_address_needs_mapping(struct device *hwdev, dma_addr_t addr, 56ec3cf2ecSBecky Bruce size_t size) 57ec3cf2ecSBecky Bruce { 58ec3cf2ecSBecky Bruce struct dma_mapping_ops *dma_ops = get_dma_ops(hwdev); 59ec3cf2ecSBecky Bruce 60ec3cf2ecSBecky Bruce BUG_ON(!dma_ops); 61ec3cf2ecSBecky Bruce return dma_ops->addr_needs_map(hwdev, addr, size); 62ec3cf2ecSBecky Bruce } 63ec3cf2ecSBecky Bruce 64ec3cf2ecSBecky Bruce /* 65ec3cf2ecSBecky Bruce * Determine if an address is reachable by a pci device, or if we must bounce. 66ec3cf2ecSBecky Bruce */ 67ec3cf2ecSBecky Bruce static int 68ec3cf2ecSBecky Bruce swiotlb_pci_addr_needs_map(struct device *hwdev, dma_addr_t addr, size_t size) 69ec3cf2ecSBecky Bruce { 70ec3cf2ecSBecky Bruce u64 mask = dma_get_mask(hwdev); 71ec3cf2ecSBecky Bruce dma_addr_t max; 72ec3cf2ecSBecky Bruce struct pci_controller *hose; 73ec3cf2ecSBecky Bruce struct pci_dev *pdev = to_pci_dev(hwdev); 74ec3cf2ecSBecky Bruce 75ec3cf2ecSBecky Bruce hose = pci_bus_to_host(pdev->bus); 76ec3cf2ecSBecky Bruce max = hose->dma_window_base_cur + hose->dma_window_size; 77ec3cf2ecSBecky Bruce 78ec3cf2ecSBecky Bruce /* check that we're within mapped pci window space */ 79ec3cf2ecSBecky Bruce if ((addr + size > max) | (addr < hose->dma_window_base_cur)) 80ec3cf2ecSBecky Bruce return 1; 81ec3cf2ecSBecky Bruce 82ec3cf2ecSBecky Bruce return !is_buffer_dma_capable(mask, addr, size); 83ec3cf2ecSBecky Bruce } 84ec3cf2ecSBecky Bruce 85ec3cf2ecSBecky Bruce static int 86ec3cf2ecSBecky Bruce swiotlb_addr_needs_map(struct device *hwdev, dma_addr_t addr, size_t size) 87ec3cf2ecSBecky Bruce { 88ec3cf2ecSBecky Bruce return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size); 89ec3cf2ecSBecky Bruce } 90ec3cf2ecSBecky Bruce 91ec3cf2ecSBecky Bruce 92ec3cf2ecSBecky Bruce /* 93ec3cf2ecSBecky Bruce * At the moment, all platforms that use this code only require 94ec3cf2ecSBecky Bruce * swiotlb to be used if we're operating on HIGHMEM. Since 95ec3cf2ecSBecky Bruce * we don't ever call anything other than map_sg, unmap_sg, 96ec3cf2ecSBecky Bruce * map_page, and unmap_page on highmem, use normal dma_ops 97ec3cf2ecSBecky Bruce * for everything else. 98ec3cf2ecSBecky Bruce */ 99ec3cf2ecSBecky Bruce struct dma_mapping_ops swiotlb_dma_ops = { 100ec3cf2ecSBecky Bruce .alloc_coherent = dma_direct_alloc_coherent, 101ec3cf2ecSBecky Bruce .free_coherent = dma_direct_free_coherent, 102ec3cf2ecSBecky Bruce .map_sg = swiotlb_map_sg_attrs, 103ec3cf2ecSBecky Bruce .unmap_sg = swiotlb_unmap_sg_attrs, 104ec3cf2ecSBecky Bruce .dma_supported = swiotlb_dma_supported, 105ec3cf2ecSBecky Bruce .map_page = swiotlb_map_page, 106ec3cf2ecSBecky Bruce .unmap_page = swiotlb_unmap_page, 107ec3cf2ecSBecky Bruce .addr_needs_map = swiotlb_addr_needs_map, 108ec3cf2ecSBecky Bruce .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu, 109ec3cf2ecSBecky Bruce .sync_single_range_for_device = swiotlb_sync_single_range_for_device, 110ec3cf2ecSBecky Bruce .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, 111ec3cf2ecSBecky Bruce .sync_sg_for_device = swiotlb_sync_sg_for_device 112ec3cf2ecSBecky Bruce }; 113ec3cf2ecSBecky Bruce 114ec3cf2ecSBecky Bruce struct dma_mapping_ops swiotlb_pci_dma_ops = { 115ec3cf2ecSBecky Bruce .alloc_coherent = dma_direct_alloc_coherent, 116ec3cf2ecSBecky Bruce .free_coherent = dma_direct_free_coherent, 117ec3cf2ecSBecky Bruce .map_sg = swiotlb_map_sg_attrs, 118ec3cf2ecSBecky Bruce .unmap_sg = swiotlb_unmap_sg_attrs, 119ec3cf2ecSBecky Bruce .dma_supported = swiotlb_dma_supported, 120ec3cf2ecSBecky Bruce .map_page = swiotlb_map_page, 121ec3cf2ecSBecky Bruce .unmap_page = swiotlb_unmap_page, 122ec3cf2ecSBecky Bruce .addr_needs_map = swiotlb_pci_addr_needs_map, 123ec3cf2ecSBecky Bruce .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu, 124ec3cf2ecSBecky Bruce .sync_single_range_for_device = swiotlb_sync_single_range_for_device, 125ec3cf2ecSBecky Bruce .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, 126ec3cf2ecSBecky Bruce .sync_sg_for_device = swiotlb_sync_sg_for_device 127ec3cf2ecSBecky Bruce }; 128ec3cf2ecSBecky Bruce 129ec3cf2ecSBecky Bruce static int ppc_swiotlb_bus_notify(struct notifier_block *nb, 130ec3cf2ecSBecky Bruce unsigned long action, void *data) 131ec3cf2ecSBecky Bruce { 132ec3cf2ecSBecky Bruce struct device *dev = data; 133ec3cf2ecSBecky Bruce 134ec3cf2ecSBecky Bruce /* We are only intereted in device addition */ 135ec3cf2ecSBecky Bruce if (action != BUS_NOTIFY_ADD_DEVICE) 136ec3cf2ecSBecky Bruce return 0; 137ec3cf2ecSBecky Bruce 138ec3cf2ecSBecky Bruce /* May need to bounce if the device can't address all of DRAM */ 139ec3cf2ecSBecky Bruce if (dma_get_mask(dev) < lmb_end_of_DRAM()) 140ec3cf2ecSBecky Bruce set_dma_ops(dev, &swiotlb_dma_ops); 141ec3cf2ecSBecky Bruce 142ec3cf2ecSBecky Bruce return NOTIFY_DONE; 143ec3cf2ecSBecky Bruce } 144ec3cf2ecSBecky Bruce 145ec3cf2ecSBecky Bruce static struct notifier_block ppc_swiotlb_plat_bus_notifier = { 146ec3cf2ecSBecky Bruce .notifier_call = ppc_swiotlb_bus_notify, 147ec3cf2ecSBecky Bruce .priority = 0, 148ec3cf2ecSBecky Bruce }; 149ec3cf2ecSBecky Bruce 150ec3cf2ecSBecky Bruce static struct notifier_block ppc_swiotlb_of_bus_notifier = { 151ec3cf2ecSBecky Bruce .notifier_call = ppc_swiotlb_bus_notify, 152ec3cf2ecSBecky Bruce .priority = 0, 153ec3cf2ecSBecky Bruce }; 154ec3cf2ecSBecky Bruce 155ec3cf2ecSBecky Bruce int __init swiotlb_setup_bus_notifier(void) 156ec3cf2ecSBecky Bruce { 157ec3cf2ecSBecky Bruce bus_register_notifier(&platform_bus_type, 158ec3cf2ecSBecky Bruce &ppc_swiotlb_plat_bus_notifier); 159ec3cf2ecSBecky Bruce bus_register_notifier(&of_platform_bus_type, 160ec3cf2ecSBecky Bruce &ppc_swiotlb_of_bus_notifier); 161ec3cf2ecSBecky Bruce 162ec3cf2ecSBecky Bruce return 0; 163ec3cf2ecSBecky Bruce } 164