Release 4.14 arch/openrisc/kernel/dma.c
/*
* OpenRISC Linux
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* Modifications for the OpenRISC architecture:
* Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
*
* 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.
*
* DMA mapping callbacks...
* As alloc_coherent is the only DMA callback being used currently, that's
* the only thing implemented properly. The rest need looking into...
*/
#include <linux/dma-mapping.h>
#include <linux/dma-debug.h>
#include <linux/export.h>
#include <asm/cpuinfo.h>
#include <asm/spr_defs.h>
#include <asm/tlbflush.h>
static int
page_set_nocache(pte_t *pte, unsigned long addr,
unsigned long next, struct mm_walk *walk)
{
unsigned long cl;
pte_val(*pte) |= _PAGE_CI;
/*
* Flush the page out of the TLB so that the new page flags get
* picked up next time there's an access
*/
flush_tlb_page(NULL, addr);
/* Flush page out of dcache */
for (cl = __pa(addr); cl < __pa(next); cl += cpuinfo.dcache_block_size)
mtspr(SPR_DCBFR, cl);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 76 | 100.00% | 1 | 100.00% |
| Total | 76 | 100.00% | 1 | 100.00% |
static int
page_clear_nocache(pte_t *pte, unsigned long addr,
unsigned long next, struct mm_walk *walk)
{
pte_val(*pte) &= ~_PAGE_CI;
/*
* Flush the page out of the TLB so that the new page flags get
* picked up next time there's an access
*/
flush_tlb_page(NULL, addr);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 43 | 100.00% | 1 | 100.00% |
| Total | 43 | 100.00% | 1 | 100.00% |
/*
* Alloc "coherent" memory, which for OpenRISC means simply uncached.
*
* This function effectively just calls __get_free_pages, sets the
* cache-inhibit bit on those pages, and makes sure that the pages are
* flushed out of the cache before they are used.
*
* If the NON_CONSISTENT attribute is set, then this function just
* returns "normal", cachable memory.
*
* There are additional flags WEAK_ORDERING and WRITE_COMBINE to take
* into consideration here, too. All current known implementations of
* the OR1K support only strongly ordered memory accesses, so that flag
* is being ignored for now; uncached but write-combined memory is a
* missing feature of the OR1K.
*/
static void *
or1k_dma_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp,
unsigned long attrs)
{
unsigned long va;
void *page;
struct mm_walk walk = {
.pte_entry = page_set_nocache,
.mm = &init_mm
};
page = alloc_pages_exact(size, gfp);
if (!page)
return NULL;
/* This gives us the real physical address of the first page. */
*dma_handle = __pa(page);
va = (unsigned long)page;
if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) {
/*
* We need to iterate through the pages, clearing the dcache for
* them and setting the cache-inhibit bit.
*/
if (walk_page_range(va, va + size, &walk)) {
free_pages_exact(page, size);
return NULL;
}
}
return (void *)va;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 123 | 93.89% | 2 | 66.67% |
| Krzysztof Kozlowski | 8 | 6.11% | 1 | 33.33% |
| Total | 131 | 100.00% | 3 | 100.00% |
static void
or1k_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
unsigned long va = (unsigned long)vaddr;
struct mm_walk walk = {
.pte_entry = page_clear_nocache,
.mm = &init_mm
};
if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) {
/* walk_page_range shouldn't be able to fail here */
WARN_ON(walk_page_range(va, va + size, &walk));
}
free_pages_exact(vaddr, size);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 79 | 90.80% | 2 | 66.67% |
| Krzysztof Kozlowski | 8 | 9.20% | 1 | 33.33% |
| Total | 87 | 100.00% | 3 | 100.00% |
static dma_addr_t
or1k_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
unsigned long attrs)
{
unsigned long cl;
dma_addr_t addr = page_to_phys(page) + offset;
if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
return addr;
switch (dir) {
case DMA_TO_DEVICE:
/* Flush the dcache for the requested range */
for (cl = addr; cl < addr + size;
cl += cpuinfo.dcache_block_size)
mtspr(SPR_DCBFR, cl);
break;
case DMA_FROM_DEVICE:
/* Invalidate the dcache for the requested range */
for (cl = addr; cl < addr + size;
cl += cpuinfo.dcache_block_size)
mtspr(SPR_DCBIR, cl);
break;
default:
/*
* NOTE: If dir == DMA_BIDIRECTIONAL then there's no need to
* flush nor invalidate the cache here as the area will need
* to be manually synced anyway.
*/
break;
}
return addr;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 115 | 91.27% | 2 | 50.00% |
| Alexander Duyck | 9 | 7.14% | 1 | 25.00% |
| Krzysztof Kozlowski | 2 | 1.59% | 1 | 25.00% |
| Total | 126 | 100.00% | 4 | 100.00% |
static void
or1k_unmap_page(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction dir,
unsigned long attrs)
{
/* Nothing special to do here... */
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 24 | 92.31% | 2 | 66.67% |
| Krzysztof Kozlowski | 2 | 7.69% | 1 | 33.33% |
| Total | 26 | 100.00% | 3 | 100.00% |
static int
or1k_map_sg(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir,
unsigned long attrs)
{
struct scatterlist *s;
int i;
for_each_sg(sg, s, nents, i) {
s->dma_address = or1k_map_page(dev, sg_page(s), s->offset,
s->length, dir, 0);
}
return nents;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 73 | 96.05% | 2 | 66.67% |
| Krzysztof Kozlowski | 3 | 3.95% | 1 | 33.33% |
| Total | 76 | 100.00% | 3 | 100.00% |
static void
or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir,
unsigned long attrs)
{
struct scatterlist *s;
int i;
for_each_sg(sg, s, nents, i) {
or1k_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir, 0);
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 63 | 95.45% | 2 | 66.67% |
| Krzysztof Kozlowski | 3 | 4.55% | 1 | 33.33% |
| Total | 66 | 100.00% | 3 | 100.00% |
static void
or1k_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size,
enum dma_data_direction dir)
{
unsigned long cl;
dma_addr_t addr = dma_handle;
/* Invalidate the dcache for the requested range */
for (cl = addr; cl < addr + size; cl += cpuinfo.dcache_block_size)
mtspr(SPR_DCBIR, cl);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 56 | 100.00% | 2 | 100.00% |
| Total | 56 | 100.00% | 2 | 100.00% |
static void
or1k_sync_single_for_device(struct device *dev,
dma_addr_t dma_handle, size_t size,
enum dma_data_direction dir)
{
unsigned long cl;
dma_addr_t addr = dma_handle;
/* Flush the dcache for the requested range */
for (cl = addr; cl < addr + size; cl += cpuinfo.dcache_block_size)
mtspr(SPR_DCBFR, cl);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 56 | 100.00% | 2 | 100.00% |
| Total | 56 | 100.00% | 2 | 100.00% |
const struct dma_map_ops or1k_dma_map_ops = {
.alloc = or1k_dma_alloc,
.free = or1k_dma_free,
.map_page = or1k_map_page,
.unmap_page = or1k_unmap_page,
.map_sg = or1k_map_sg,
.unmap_sg = or1k_unmap_sg,
.sync_single_for_cpu = or1k_sync_single_for_cpu,
.sync_single_for_device = or1k_sync_single_for_device,
};
EXPORT_SYMBOL(or1k_dma_map_ops);
/* Number of entries preallocated for DMA-API debugging */
#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
static int __init dma_init(void)
{
dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
return 0;
}
Contributors
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| Jonas Bonn | 17 | 100.00% | 1 | 100.00% |
| Total | 17 | 100.00% | 1 | 100.00% |
fs_initcall(dma_init);
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Jonas Bonn | 806 | 95.72% | 3 | 50.00% |
| Krzysztof Kozlowski | 26 | 3.09% | 1 | 16.67% |
| Alexander Duyck | 9 | 1.07% | 1 | 16.67% |
| Bart Van Assche | 1 | 0.12% | 1 | 16.67% |
| Total | 842 | 100.00% | 6 | 100.00% |
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