[net-next-2.6.git] / arch / frv / mm / dma-alloc.c

/* dma-alloc.c: consistent DMA memory allocation
 *
 * Derived from arch/ppc/mm/cachemap.c
 *
 *  PowerPC version derived from arch/arm/mm/consistent.c
 *    Copyright (C) 2001 Dan Malek (dmalek@jlc.net)
 *
 *  linux/arch/arm/mm/consistent.c
 *
 *  Copyright (C) 2000 Russell King
 *
 * Consistent memory allocators.  Used for DMA devices that want to
 * share uncached memory with the processor core.  The function return
 * is the virtual address and 'dma_handle' is the physical address.
 * Mostly stolen from the ARM port, with some changes for PowerPC.
 *						-- Dan
 * Modified for 36-bit support.  -Matt
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/stddef.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/pci.h>

#include <asm/pgalloc.h>
#include <asm/io.h>
#include <asm/hardirq.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/uaccess.h>
#include <asm/smp.h>

static int map_page(unsigned long va, unsigned long pa, pgprot_t prot)
{
	pgd_t *pge;
	pud_t *pue;
	pmd_t *pme;
	pte_t *pte;
	int err = -ENOMEM;

	/* Use upper 10 bits of VA to index the first level map */
	pge = pgd_offset_k(va);
	pue = pud_offset(pge, va);
	pme = pmd_offset(pue, va);

	/* Use middle 10 bits of VA to index the second-level map */
	pte = pte_alloc_kernel(pme, va);
	if (pte != 0) {
		err = 0;
		set_pte(pte, mk_pte_phys(pa & PAGE_MASK, prot));
	}

	return err;
}

/*
 * This function will allocate the requested contiguous pages and
 * map them into the kernel's vmalloc() space.  This is done so we
 * get unique mapping for these pages, outside of the kernel's 1:1
 * virtual:physical mapping.  This is necessary so we can cover large
 * portions of the kernel with single large page TLB entries, and
 * still get unique uncached pages for consistent DMA.
 */
void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *dma_handle)
{
	struct vm_struct *area;
	unsigned long page, va, pa;
	void *ret;
	int order, err, i;

	if (in_interrupt())
		BUG();

	/* only allocate page size areas */
	size = PAGE_ALIGN(size);
	order = get_order(size);

	page = __get_free_pages(gfp, order);
	if (!page) {
		BUG();
		return NULL;
	}

	/* allocate some common virtual space to map the new pages */
	area = get_vm_area(size, VM_ALLOC);
	if (area == 0) {
		free_pages(page, order);
		return NULL;
	}
	va = VMALLOC_VMADDR(area->addr);
	ret = (void *) va;

	/* this gives us the real physical address of the first page */
	*dma_handle = pa = virt_to_bus((void *) page);

	/* set refcount=1 on all pages in an order>0 allocation so that vfree() will actually free
	 * all pages that were allocated.
	 */
	if (order > 0) {
		struct page *rpage = virt_to_page(page);

		for (i = 1; i < (1 << order); i++)
			set_page_count(rpage + i, 1);
	}

	err = 0;
	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
		err = map_page(va + i, pa + i, PAGE_KERNEL_NOCACHE);

	if (err) {
		vfree((void *) va);
		return NULL;
	}

	/* we need to ensure that there are no cachelines in use, or worse dirty in this area
	 * - can't do until after virtual address mappings are created
	 */
	frv_cache_invalidate(va, va + size);

	return ret;
}

/*
 * free page(s) as defined by the above mapping.
 */
void consistent_free(void *vaddr)
{
	if (in_interrupt())
		BUG();
	vfree(vaddr);
}

/*
 * make an area consistent.
 */
void consistent_sync(void *vaddr, size_t size, int direction)
{
	unsigned long start = (unsigned long) vaddr;
	unsigned long end   = start + size;

	switch (direction) {
	case PCI_DMA_NONE:
		BUG();
	case PCI_DMA_FROMDEVICE:	/* invalidate only */
		frv_cache_invalidate(start, end);
		break;
	case PCI_DMA_TODEVICE:		/* writeback only */
		frv_dcache_writeback(start, end);
		break;
	case PCI_DMA_BIDIRECTIONAL:	/* writeback and invalidate */
		frv_dcache_writeback(start, end);
		break;
	}
}

/*
 * consistent_sync_page make a page are consistent. identical
 * to consistent_sync, but takes a struct page instead of a virtual address
 */

void consistent_sync_page(struct page *page, unsigned long offset,
			  size_t size, int direction)
{
	void *start;

	start = page_address(page) + offset;
	consistent_sync(start, size, direction);
}
Commit	Line	Data
1da177e4 LT	1	/* dma-alloc.c: consistent DMA memory allocation
	2	*
	3	* Derived from arch/ppc/mm/cachemap.c
	4	*
	5	* PowerPC version derived from arch/arm/mm/consistent.c
	6	* Copyright (C) 2001 Dan Malek (dmalek@jlc.net)
	7	*
	8	* linux/arch/arm/mm/consistent.c
	9	*
	10	* Copyright (C) 2000 Russell King
	11	*
	12	* Consistent memory allocators. Used for DMA devices that want to
	13	* share uncached memory with the processor core. The function return
	14	* is the virtual address and 'dma_handle' is the physical address.
	15	* Mostly stolen from the ARM port, with some changes for PowerPC.
	16	* -- Dan
	17	* Modified for 36-bit support. -Matt
	18	*
	19	* This program is free software; you can redistribute it and/or modify
	20	* it under the terms of the GNU General Public License version 2 as
	21	* published by the Free Software Foundation.
	22	*/
	23
	24	#include <linux/config.h>
	25	#include <linux/module.h>
	26	#include <linux/signal.h>
	27	#include <linux/sched.h>
	28	#include <linux/kernel.h>
	29	#include <linux/errno.h>
	30	#include <linux/string.h>
	31	#include <linux/types.h>
	32	#include <linux/ptrace.h>
	33	#include <linux/mman.h>
	34	#include <linux/mm.h>
	35	#include <linux/swap.h>
	36	#include <linux/stddef.h>
	37	#include <linux/vmalloc.h>
	38	#include <linux/init.h>
	39	#include <linux/pci.h>
	40
	41	#include <asm/pgalloc.h>
	42	#include <asm/io.h>
	43	#include <asm/hardirq.h>
	44	#include <asm/mmu_context.h>
	45	#include <asm/pgtable.h>
	46	#include <asm/mmu.h>
	47	#include <asm/uaccess.h>
	48	#include <asm/smp.h>
	49
	50	static int map_page(unsigned long va, unsigned long pa, pgprot_t prot)
	51	{
	52	pgd_t *pge;
	53	pud_t *pue;
	54	pmd_t *pme;
	55	pte_t *pte;
	56	int err = -ENOMEM;
	57
1da177e4 LT	58	/* Use upper 10 bits of VA to index the first level map */
	59	pge = pgd_offset_k(va);
	60	pue = pud_offset(pge, va);
	61	pme = pmd_offset(pue, va);
	62
	63	/* Use middle 10 bits of VA to index the second-level map */
872fec16	64	pte = pte_alloc_kernel(pme, va);
1da177e4 LT	65	if (pte != 0) {
	66	err = 0;
	67	set_pte(pte, mk_pte_phys(pa & PAGE_MASK, prot));
	68	}
	69
1da177e4 LT	70	return err;
	71	}
	72
	73	/*
	74	* This function will allocate the requested contiguous pages and
	75	* map them into the kernel's vmalloc() space. This is done so we
	76	* get unique mapping for these pages, outside of the kernel's 1:1
	77	* virtual:physical mapping. This is necessary so we can cover large
	78	* portions of the kernel with single large page TLB entries, and
	79	* still get unique uncached pages for consistent DMA.
	80	*/
a5da7d3c	81	void consistent_alloc(gfp_t gfp, size_t size, dma_addr_t dma_handle)
1da177e4 LT	82	{
	83	struct vm_struct *area;
	84	unsigned long page, va, pa;
	85	void *ret;
	86	int order, err, i;
	87
	88	if (in_interrupt())
	89	BUG();
	90
	91	/* only allocate page size areas */
	92	size = PAGE_ALIGN(size);
	93	order = get_order(size);
	94
	95	page = __get_free_pages(gfp, order);
	96	if (!page) {
	97	BUG();
	98	return NULL;
	99	}
	100
	101	/* allocate some common virtual space to map the new pages */
	102	area = get_vm_area(size, VM_ALLOC);
	103	if (area == 0) {
	104	free_pages(page, order);
	105	return NULL;
	106	}
	107	va = VMALLOC_VMADDR(area->addr);
	108	ret = (void *) va;
	109
	110	/* this gives us the real physical address of the first page */
	111	dma_handle = pa = virt_to_bus((void ) page);
	112
	113	/* set refcount=1 on all pages in an order>0 allocation so that vfree() will actually free
	114	* all pages that were allocated.
	115	*/
	116	if (order > 0) {
	117	struct page *rpage = virt_to_page(page);
	118
	119	for (i = 1; i < (1 << order); i++)
	120	set_page_count(rpage + i, 1);
	121	}
	122
	123	err = 0;
	124	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
	125	err = map_page(va + i, pa + i, PAGE_KERNEL_NOCACHE);
	126
	127	if (err) {
	128	vfree((void *) va);
	129	return NULL;
	130	}
	131
	132	/* we need to ensure that there are no cachelines in use, or worse dirty in this area
	133	* - can't do until after virtual address mappings are created
	134	*/
	135	frv_cache_invalidate(va, va + size);
	136
	137	return ret;
	138	}
	139
	140	/*
	141	* free page(s) as defined by the above mapping.
	142	*/
	143	void consistent_free(void *vaddr)
	144	{
	145	if (in_interrupt())
146	BUG();
147	vfree(vaddr);
148	}
149
150	/*
151	* make an area consistent.
152	*/
153	void consistent_sync(void *vaddr, size_t size, int direction)
154	{
155	unsigned long start = (unsigned long) vaddr;
156	unsigned long end = start + size;
157
158	switch (direction) {
159	case PCI_DMA_NONE:
160	BUG();
161	case PCI_DMA_FROMDEVICE: /* invalidate only */
162	frv_cache_invalidate(start, end);
163	break;
164	case PCI_DMA_TODEVICE: /* writeback only */
165	frv_dcache_writeback(start, end);
166	break;
167	case PCI_DMA_BIDIRECTIONAL: /* writeback and invalidate */
168	frv_dcache_writeback(start, end);
169	break;
170	}
171	}
172
173	/*
174	* consistent_sync_page make a page are consistent. identical
175	* to consistent_sync, but takes a struct page instead of a virtual address
176	*/
177
178	void consistent_sync_page(struct page *page, unsigned long offset,
179	size_t size, int direction)
180	{
181	void *start;
182
183	start = page_address(page) + offset;
184	consistent_sync(start, size, direction);
185	}