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author | Kevin | 2014-11-15 09:58:27 +0800 |
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committer | Kevin | 2014-11-15 09:58:27 +0800 |
commit | 392e8802486cb573b916e746010e141a75f507e6 (patch) | |
tree | 50029aca02c81f087b90336e670b44e510782330 /ANDROID_3.4.5/arch/powerpc/kernel/iommu.c | |
download | FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.gz FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.bz2 FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.zip |
init android origin source code
Diffstat (limited to 'ANDROID_3.4.5/arch/powerpc/kernel/iommu.c')
-rw-r--r-- | ANDROID_3.4.5/arch/powerpc/kernel/iommu.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/arch/powerpc/kernel/iommu.c b/ANDROID_3.4.5/arch/powerpc/kernel/iommu.c new file mode 100644 index 00000000..359f0785 --- /dev/null +++ b/ANDROID_3.4.5/arch/powerpc/kernel/iommu.c @@ -0,0 +1,685 @@ +/* + * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation + * + * Rewrite, cleanup, new allocation schemes, virtual merging: + * Copyright (C) 2004 Olof Johansson, IBM Corporation + * and Ben. Herrenschmidt, IBM Corporation + * + * Dynamic DMA mapping support, bus-independent parts. + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + + +#include <linux/init.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/spinlock.h> +#include <linux/string.h> +#include <linux/dma-mapping.h> +#include <linux/bitmap.h> +#include <linux/iommu-helper.h> +#include <linux/crash_dump.h> +#include <asm/io.h> +#include <asm/prom.h> +#include <asm/iommu.h> +#include <asm/pci-bridge.h> +#include <asm/machdep.h> +#include <asm/kdump.h> +#include <asm/fadump.h> + +#define DBG(...) + +static int novmerge; + +static void __iommu_free(struct iommu_table *, dma_addr_t, unsigned int); + +static int __init setup_iommu(char *str) +{ + if (!strcmp(str, "novmerge")) + novmerge = 1; + else if (!strcmp(str, "vmerge")) + novmerge = 0; + return 1; +} + +__setup("iommu=", setup_iommu); + +static unsigned long iommu_range_alloc(struct device *dev, + struct iommu_table *tbl, + unsigned long npages, + unsigned long *handle, + unsigned long mask, + unsigned int align_order) +{ + unsigned long n, end, start; + unsigned long limit; + int largealloc = npages > 15; + int pass = 0; + unsigned long align_mask; + unsigned long boundary_size; + + align_mask = 0xffffffffffffffffl >> (64 - align_order); + + /* This allocator was derived from x86_64's bit string search */ + + /* Sanity check */ + if (unlikely(npages == 0)) { + if (printk_ratelimit()) + WARN_ON(1); + return DMA_ERROR_CODE; + } + + if (handle && *handle) + start = *handle; + else + start = largealloc ? tbl->it_largehint : tbl->it_hint; + + /* Use only half of the table for small allocs (15 pages or less) */ + limit = largealloc ? tbl->it_size : tbl->it_halfpoint; + + if (largealloc && start < tbl->it_halfpoint) + start = tbl->it_halfpoint; + + /* The case below can happen if we have a small segment appended + * to a large, or when the previous alloc was at the very end of + * the available space. If so, go back to the initial start. + */ + if (start >= limit) + start = largealloc ? tbl->it_largehint : tbl->it_hint; + + again: + + if (limit + tbl->it_offset > mask) { + limit = mask - tbl->it_offset + 1; + /* If we're constrained on address range, first try + * at the masked hint to avoid O(n) search complexity, + * but on second pass, start at 0. + */ + if ((start & mask) >= limit || pass > 0) + start = 0; + else + start &= mask; + } + + if (dev) + boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, + 1 << IOMMU_PAGE_SHIFT); + else + boundary_size = ALIGN(1UL << 32, 1 << IOMMU_PAGE_SHIFT); + /* 4GB boundary for iseries_hv_alloc and iseries_hv_map */ + + n = iommu_area_alloc(tbl->it_map, limit, start, npages, + tbl->it_offset, boundary_size >> IOMMU_PAGE_SHIFT, + align_mask); + if (n == -1) { + if (likely(pass < 2)) { + /* First failure, just rescan the half of the table. + * Second failure, rescan the other half of the table. + */ + start = (largealloc ^ pass) ? tbl->it_halfpoint : 0; + limit = pass ? tbl->it_size : limit; + pass++; + goto again; + } else { + /* Third failure, give up */ + return DMA_ERROR_CODE; + } + } + + end = n + npages; + + /* Bump the hint to a new block for small allocs. */ + if (largealloc) { + /* Don't bump to new block to avoid fragmentation */ + tbl->it_largehint = end; + } else { + /* Overflow will be taken care of at the next allocation */ + tbl->it_hint = (end + tbl->it_blocksize - 1) & + ~(tbl->it_blocksize - 1); + } + + /* Update handle for SG allocations */ + if (handle) + *handle = end; + + return n; +} + +static dma_addr_t iommu_alloc(struct device *dev, struct iommu_table *tbl, + void *page, unsigned int npages, + enum dma_data_direction direction, + unsigned long mask, unsigned int align_order, + struct dma_attrs *attrs) +{ + unsigned long entry, flags; + dma_addr_t ret = DMA_ERROR_CODE; + int build_fail; + + spin_lock_irqsave(&(tbl->it_lock), flags); + + entry = iommu_range_alloc(dev, tbl, npages, NULL, mask, align_order); + + if (unlikely(entry == DMA_ERROR_CODE)) { + spin_unlock_irqrestore(&(tbl->it_lock), flags); + return DMA_ERROR_CODE; + } + + entry += tbl->it_offset; /* Offset into real TCE table */ + ret = entry << IOMMU_PAGE_SHIFT; /* Set the return dma address */ + + /* Put the TCEs in the HW table */ + build_fail = ppc_md.tce_build(tbl, entry, npages, + (unsigned long)page & IOMMU_PAGE_MASK, + direction, attrs); + + /* ppc_md.tce_build() only returns non-zero for transient errors. + * Clean up the table bitmap in this case and return + * DMA_ERROR_CODE. For all other errors the functionality is + * not altered. + */ + if (unlikely(build_fail)) { + __iommu_free(tbl, ret, npages); + + spin_unlock_irqrestore(&(tbl->it_lock), flags); + return DMA_ERROR_CODE; + } + + /* Flush/invalidate TLB caches if necessary */ + if (ppc_md.tce_flush) + ppc_md.tce_flush(tbl); + + spin_unlock_irqrestore(&(tbl->it_lock), flags); + + /* Make sure updates are seen by hardware */ + mb(); + + return ret; +} + +static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr, + unsigned int npages) +{ + unsigned long entry, free_entry; + + entry = dma_addr >> IOMMU_PAGE_SHIFT; + free_entry = entry - tbl->it_offset; + + if (((free_entry + npages) > tbl->it_size) || + (entry < tbl->it_offset)) { + if (printk_ratelimit()) { + printk(KERN_INFO "iommu_free: invalid entry\n"); + printk(KERN_INFO "\tentry = 0x%lx\n", entry); + printk(KERN_INFO "\tdma_addr = 0x%llx\n", (u64)dma_addr); + printk(KERN_INFO "\tTable = 0x%llx\n", (u64)tbl); + printk(KERN_INFO "\tbus# = 0x%llx\n", (u64)tbl->it_busno); + printk(KERN_INFO "\tsize = 0x%llx\n", (u64)tbl->it_size); + printk(KERN_INFO "\tstartOff = 0x%llx\n", (u64)tbl->it_offset); + printk(KERN_INFO "\tindex = 0x%llx\n", (u64)tbl->it_index); + WARN_ON(1); + } + return; + } + + ppc_md.tce_free(tbl, entry, npages); + bitmap_clear(tbl->it_map, free_entry, npages); +} + +static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr, + unsigned int npages) +{ + unsigned long flags; + + spin_lock_irqsave(&(tbl->it_lock), flags); + + __iommu_free(tbl, dma_addr, npages); + + /* Make sure TLB cache is flushed if the HW needs it. We do + * not do an mb() here on purpose, it is not needed on any of + * the current platforms. + */ + if (ppc_md.tce_flush) + ppc_md.tce_flush(tbl); + + spin_unlock_irqrestore(&(tbl->it_lock), flags); +} + +int iommu_map_sg(struct device *dev, struct iommu_table *tbl, + struct scatterlist *sglist, int nelems, + unsigned long mask, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + dma_addr_t dma_next = 0, dma_addr; + unsigned long flags; + struct scatterlist *s, *outs, *segstart; + int outcount, incount, i, build_fail = 0; + unsigned int align; + unsigned long handle; + unsigned int max_seg_size; + + BUG_ON(direction == DMA_NONE); + + if ((nelems == 0) || !tbl) + return 0; + + outs = s = segstart = &sglist[0]; + outcount = 1; + incount = nelems; + handle = 0; + + /* Init first segment length for backout at failure */ + outs->dma_length = 0; + + DBG("sg mapping %d elements:\n", nelems); + + spin_lock_irqsave(&(tbl->it_lock), flags); + + max_seg_size = dma_get_max_seg_size(dev); + for_each_sg(sglist, s, nelems, i) { + unsigned long vaddr, npages, entry, slen; + + slen = s->length; + /* Sanity check */ + if (slen == 0) { + dma_next = 0; + continue; + } + /* Allocate iommu entries for that segment */ + vaddr = (unsigned long) sg_virt(s); + npages = iommu_num_pages(vaddr, slen, IOMMU_PAGE_SIZE); + align = 0; + if (IOMMU_PAGE_SHIFT < PAGE_SHIFT && slen >= PAGE_SIZE && + (vaddr & ~PAGE_MASK) == 0) + align = PAGE_SHIFT - IOMMU_PAGE_SHIFT; + entry = iommu_range_alloc(dev, tbl, npages, &handle, + mask >> IOMMU_PAGE_SHIFT, align); + + DBG(" - vaddr: %lx, size: %lx\n", vaddr, slen); + + /* Handle failure */ + if (unlikely(entry == DMA_ERROR_CODE)) { + if (printk_ratelimit()) + dev_info(dev, "iommu_alloc failed, tbl %p " + "vaddr %lx npages %lu\n", tbl, vaddr, + npages); + goto failure; + } + + /* Convert entry to a dma_addr_t */ + entry += tbl->it_offset; + dma_addr = entry << IOMMU_PAGE_SHIFT; + dma_addr |= (s->offset & ~IOMMU_PAGE_MASK); + + DBG(" - %lu pages, entry: %lx, dma_addr: %lx\n", + npages, entry, dma_addr); + + /* Insert into HW table */ + build_fail = ppc_md.tce_build(tbl, entry, npages, + vaddr & IOMMU_PAGE_MASK, + direction, attrs); + if(unlikely(build_fail)) + goto failure; + + /* If we are in an open segment, try merging */ + if (segstart != s) { + DBG(" - trying merge...\n"); + /* We cannot merge if: + * - allocated dma_addr isn't contiguous to previous allocation + */ + if (novmerge || (dma_addr != dma_next) || + (outs->dma_length + s->length > max_seg_size)) { + /* Can't merge: create a new segment */ + segstart = s; + outcount++; + outs = sg_next(outs); + DBG(" can't merge, new segment.\n"); + } else { + outs->dma_length += s->length; + DBG(" merged, new len: %ux\n", outs->dma_length); + } + } + + if (segstart == s) { + /* This is a new segment, fill entries */ + DBG(" - filling new segment.\n"); + outs->dma_address = dma_addr; + outs->dma_length = slen; + } + + /* Calculate next page pointer for contiguous check */ + dma_next = dma_addr + slen; + + DBG(" - dma next is: %lx\n", dma_next); + } + + /* Flush/invalidate TLB caches if necessary */ + if (ppc_md.tce_flush) + ppc_md.tce_flush(tbl); + + spin_unlock_irqrestore(&(tbl->it_lock), flags); + + DBG("mapped %d elements:\n", outcount); + + /* For the sake of iommu_unmap_sg, we clear out the length in the + * next entry of the sglist if we didn't fill the list completely + */ + if (outcount < incount) { + outs = sg_next(outs); + outs->dma_address = DMA_ERROR_CODE; + outs->dma_length = 0; + } + + /* Make sure updates are seen by hardware */ + mb(); + + return outcount; + + failure: + for_each_sg(sglist, s, nelems, i) { + if (s->dma_length != 0) { + unsigned long vaddr, npages; + + vaddr = s->dma_address & IOMMU_PAGE_MASK; + npages = iommu_num_pages(s->dma_address, s->dma_length, + IOMMU_PAGE_SIZE); + __iommu_free(tbl, vaddr, npages); + s->dma_address = DMA_ERROR_CODE; + s->dma_length = 0; + } + if (s == outs) + break; + } + spin_unlock_irqrestore(&(tbl->it_lock), flags); + return 0; +} + + +void iommu_unmap_sg(struct iommu_table *tbl, struct scatterlist *sglist, + int nelems, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct scatterlist *sg; + unsigned long flags; + + BUG_ON(direction == DMA_NONE); + + if (!tbl) + return; + + spin_lock_irqsave(&(tbl->it_lock), flags); + + sg = sglist; + while (nelems--) { + unsigned int npages; + dma_addr_t dma_handle = sg->dma_address; + + if (sg->dma_length == 0) + break; + npages = iommu_num_pages(dma_handle, sg->dma_length, + IOMMU_PAGE_SIZE); + __iommu_free(tbl, dma_handle, npages); + sg = sg_next(sg); + } + + /* Flush/invalidate TLBs if necessary. As for iommu_free(), we + * do not do an mb() here, the affected platforms do not need it + * when freeing. + */ + if (ppc_md.tce_flush) + ppc_md.tce_flush(tbl); + + spin_unlock_irqrestore(&(tbl->it_lock), flags); +} + +static void iommu_table_clear(struct iommu_table *tbl) +{ + /* + * In case of firmware assisted dump system goes through clean + * reboot process at the time of system crash. Hence it's safe to + * clear the TCE entries if firmware assisted dump is active. + */ + if (!is_kdump_kernel() || is_fadump_active()) { + /* Clear the table in case firmware left allocations in it */ + ppc_md.tce_free(tbl, tbl->it_offset, tbl->it_size); + return; + } + +#ifdef CONFIG_CRASH_DUMP + if (ppc_md.tce_get) { + unsigned long index, tceval, tcecount = 0; + + /* Reserve the existing mappings left by the first kernel. */ + for (index = 0; index < tbl->it_size; index++) { + tceval = ppc_md.tce_get(tbl, index + tbl->it_offset); + /* + * Freed TCE entry contains 0x7fffffffffffffff on JS20 + */ + if (tceval && (tceval != 0x7fffffffffffffffUL)) { + __set_bit(index, tbl->it_map); + tcecount++; + } + } + + if ((tbl->it_size - tcecount) < KDUMP_MIN_TCE_ENTRIES) { + printk(KERN_WARNING "TCE table is full; freeing "); + printk(KERN_WARNING "%d entries for the kdump boot\n", + KDUMP_MIN_TCE_ENTRIES); + for (index = tbl->it_size - KDUMP_MIN_TCE_ENTRIES; + index < tbl->it_size; index++) + __clear_bit(index, tbl->it_map); + } + } +#endif +} + +/* + * Build a iommu_table structure. This contains a bit map which + * is used to manage allocation of the tce space. + */ +struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid) +{ + unsigned long sz; + static int welcomed = 0; + struct page *page; + + /* Set aside 1/4 of the table for large allocations. */ + tbl->it_halfpoint = tbl->it_size * 3 / 4; + + /* number of bytes needed for the bitmap */ + sz = (tbl->it_size + 7) >> 3; + + page = alloc_pages_node(nid, GFP_ATOMIC, get_order(sz)); + if (!page) + panic("iommu_init_table: Can't allocate %ld bytes\n", sz); + tbl->it_map = page_address(page); + memset(tbl->it_map, 0, sz); + + /* + * Reserve page 0 so it will not be used for any mappings. + * This avoids buggy drivers that consider page 0 to be invalid + * to crash the machine or even lose data. + */ + if (tbl->it_offset == 0) + set_bit(0, tbl->it_map); + + tbl->it_hint = 0; + tbl->it_largehint = tbl->it_halfpoint; + spin_lock_init(&tbl->it_lock); + + iommu_table_clear(tbl); + + if (!welcomed) { + printk(KERN_INFO "IOMMU table initialized, virtual merging %s\n", + novmerge ? "disabled" : "enabled"); + welcomed = 1; + } + + return tbl; +} + +void iommu_free_table(struct iommu_table *tbl, const char *node_name) +{ + unsigned long bitmap_sz, i; + unsigned int order; + + if (!tbl || !tbl->it_map) { + printk(KERN_ERR "%s: expected TCE map for %s\n", __func__, + node_name); + return; + } + + /* verify that table contains no entries */ + /* it_size is in entries, and we're examining 64 at a time */ + for (i = 0; i < (tbl->it_size/64); i++) { + if (tbl->it_map[i] != 0) { + printk(KERN_WARNING "%s: Unexpected TCEs for %s\n", + __func__, node_name); + break; + } + } + + /* calculate bitmap size in bytes */ + bitmap_sz = (tbl->it_size + 7) / 8; + + /* free bitmap */ + order = get_order(bitmap_sz); + free_pages((unsigned long) tbl->it_map, order); + + /* free table */ + kfree(tbl); +} + +/* Creates TCEs for a user provided buffer. The user buffer must be + * contiguous real kernel storage (not vmalloc). The address passed here + * comprises a page address and offset into that page. The dma_addr_t + * returned will point to the same byte within the page as was passed in. + */ +dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl, + struct page *page, unsigned long offset, size_t size, + unsigned long mask, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + dma_addr_t dma_handle = DMA_ERROR_CODE; + void *vaddr; + unsigned long uaddr; + unsigned int npages, align; + + BUG_ON(direction == DMA_NONE); + + vaddr = page_address(page) + offset; + uaddr = (unsigned long)vaddr; + npages = iommu_num_pages(uaddr, size, IOMMU_PAGE_SIZE); + + if (tbl) { + align = 0; + if (IOMMU_PAGE_SHIFT < PAGE_SHIFT && size >= PAGE_SIZE && + ((unsigned long)vaddr & ~PAGE_MASK) == 0) + align = PAGE_SHIFT - IOMMU_PAGE_SHIFT; + + dma_handle = iommu_alloc(dev, tbl, vaddr, npages, direction, + mask >> IOMMU_PAGE_SHIFT, align, + attrs); + if (dma_handle == DMA_ERROR_CODE) { + if (printk_ratelimit()) { + dev_info(dev, "iommu_alloc failed, tbl %p " + "vaddr %p npages %d\n", tbl, vaddr, + npages); + } + } else + dma_handle |= (uaddr & ~IOMMU_PAGE_MASK); + } + + return dma_handle; +} + +void iommu_unmap_page(struct iommu_table *tbl, dma_addr_t dma_handle, + size_t size, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + unsigned int npages; + + BUG_ON(direction == DMA_NONE); + + if (tbl) { + npages = iommu_num_pages(dma_handle, size, IOMMU_PAGE_SIZE); + iommu_free(tbl, dma_handle, npages); + } +} + +/* Allocates a contiguous real buffer and creates mappings over it. + * Returns the virtual address of the buffer and sets dma_handle + * to the dma address (mapping) of the first page. + */ +void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl, + size_t size, dma_addr_t *dma_handle, + unsigned long mask, gfp_t flag, int node) +{ + void *ret = NULL; + dma_addr_t mapping; + unsigned int order; + unsigned int nio_pages, io_order; + struct page *page; + + size = PAGE_ALIGN(size); + order = get_order(size); + + /* + * Client asked for way too much space. This is checked later + * anyway. It is easier to debug here for the drivers than in + * the tce tables. + */ + if (order >= IOMAP_MAX_ORDER) { + dev_info(dev, "iommu_alloc_consistent size too large: 0x%lx\n", + size); + return NULL; + } + + if (!tbl) + return NULL; + + /* Alloc enough pages (and possibly more) */ + page = alloc_pages_node(node, flag, order); + if (!page) + return NULL; + ret = page_address(page); + memset(ret, 0, size); + + /* Set up tces to cover the allocated range */ + nio_pages = size >> IOMMU_PAGE_SHIFT; + io_order = get_iommu_order(size); + mapping = iommu_alloc(dev, tbl, ret, nio_pages, DMA_BIDIRECTIONAL, + mask >> IOMMU_PAGE_SHIFT, io_order, NULL); + if (mapping == DMA_ERROR_CODE) { + free_pages((unsigned long)ret, order); + return NULL; + } + *dma_handle = mapping; + return ret; +} + +void iommu_free_coherent(struct iommu_table *tbl, size_t size, + void *vaddr, dma_addr_t dma_handle) +{ + if (tbl) { + unsigned int nio_pages; + + size = PAGE_ALIGN(size); + nio_pages = size >> IOMMU_PAGE_SHIFT; + iommu_free(tbl, dma_handle, nio_pages); + size = PAGE_ALIGN(size); + free_pages((unsigned long)vaddr, get_order(size)); + } +} |