pci-dma.c

来自「linux 内核源代码」· C语言 代码 · 共 603 行 · 第 1/2 页

	u_long mask, flags;
	unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
	unsigned int pages_mapped = size >> PAGE_SHIFT;

	mask = (u_long) -1L;
 	mask >>= BITS_PER_LONG - pages_mapped;

	DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n", 
		res_idx, size, pages_mapped, mask);

	spin_lock_irqsave(&pcxl_res_lock, flags);

	if(pages_mapped <= 8) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 8);
	} else if(pages_mapped <= 16) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 16);
	} else if(pages_mapped <= 32) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 32);
	} else {
		panic("%s: pcxl_free_range() Too many pages to unmap.\n",
		      __FILE__);
	}
	
	pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
	pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);

	spin_unlock_irqrestore(&pcxl_res_lock, flags);

	dump_resmap();
}

static int proc_pcxl_dma_show(struct seq_file *m, void *v)
{
#if 0
	u_long i = 0;
	unsigned long *res_ptr = (u_long *)pcxl_res_map;
#endif
	unsigned long total_pages = pcxl_res_size << 3;   /* 8 bits per byte */

	seq_printf(m, "\nDMA Mapping Area size    : %d bytes (%ld pages)\n",
		PCXL_DMA_MAP_SIZE, total_pages);

	seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);

	seq_puts(m,  "     	  total:    free:    used:   % used:\n");
	seq_printf(m, "blocks  %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
		pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
		(pcxl_used_bytes * 100) / pcxl_res_size);

	seq_printf(m, "pages   %8ld %8ld %8ld %8ld%%\n", total_pages,
		total_pages - pcxl_used_pages, pcxl_used_pages,
		(pcxl_used_pages * 100 / total_pages));

#if 0
	seq_puts(m, "\nResource bitmap:");

	for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
		if ((i & 7) == 0)
		    seq_puts(m,"\n   ");
		seq_printf(m, "%s %08lx", buf, *res_ptr);
	}
#endif
	seq_putc(m, '\n');
	return 0;
}

static int proc_pcxl_dma_open(struct inode *inode, struct file *file)
{
	return single_open(file, proc_pcxl_dma_show, NULL);
}

static const struct file_operations proc_pcxl_dma_ops = {
	.owner		= THIS_MODULE,
	.open		= proc_pcxl_dma_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init
pcxl_dma_init(void)
{
	if (pcxl_dma_start == 0)
		return 0;

	spin_lock_init(&pcxl_res_lock);
	pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
	pcxl_res_hint = 0;
	pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
					    get_order(pcxl_res_size));
	memset(pcxl_res_map, 0, pcxl_res_size);
	proc_gsc_root = proc_mkdir("gsc", NULL);
	if (!proc_gsc_root)
    		printk(KERN_WARNING
			"pcxl_dma_init: Unable to create gsc /proc dir entry\n");
	else {
		struct proc_dir_entry* ent;
		ent = create_proc_entry("pcxl_dma", 0, proc_gsc_root);
		if (ent)
			ent->proc_fops = &proc_pcxl_dma_ops;
		else
			printk(KERN_WARNING
				"pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
	}
	return 0;
}

__initcall(pcxl_dma_init);

static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
{
	unsigned long vaddr;
	unsigned long paddr;
	int order;

	order = get_order(size);
	size = 1 << (order + PAGE_SHIFT);
	vaddr = pcxl_alloc_range(size);
	paddr = __get_free_pages(flag, order);
	flush_kernel_dcache_range(paddr, size);
	paddr = __pa(paddr);
	map_uncached_pages(vaddr, size, paddr);
	*dma_handle = (dma_addr_t) paddr;

#if 0
/* This probably isn't needed to support EISA cards.
** ISA cards will certainly only support 24-bit DMA addressing.
** Not clear if we can, want, or need to support ISA.
*/
	if (!dev || *dev->coherent_dma_mask < 0xffffffff)
		gfp |= GFP_DMA;
#endif
	return (void *)vaddr;
}

static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
{
	int order;

	order = get_order(size);
	size = 1 << (order + PAGE_SHIFT);
	unmap_uncached_pages((unsigned long)vaddr, size);
	pcxl_free_range((unsigned long)vaddr, size);
	free_pages((unsigned long)__va(dma_handle), order);
}

static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE) {
		printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
		BUG();
	}

	flush_kernel_dcache_range((unsigned long) addr, size);
	return virt_to_phys(addr);
}

static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE) {
		printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
		BUG();
	}

	if (direction == DMA_TO_DEVICE)
	    return;

	/*
	 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
	 * simple map/unmap case. However, it IS necessary if if
	 * pci_dma_sync_single_* has been called and the buffer reused.
	 */

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
	return;
}

static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	if (direction == DMA_NONE)
	    BUG();

	for (i = 0; i < nents; i++, sglist++ ) {
		unsigned long vaddr = sg_virt_addr(sglist);
		sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
		sg_dma_len(sglist) = sglist->length;
		flush_kernel_dcache_range(vaddr, sglist->length);
	}
	return nents;
}

static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	if (direction == DMA_NONE)
	    BUG();

	if (direction == DMA_TO_DEVICE)
	    return;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
	return;
}

static void pa11_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE)
	    BUG();

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
}

static void pa11_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE)
	    BUG();

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
}

static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
}

static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
}

struct hppa_dma_ops pcxl_dma_ops = {
	.dma_supported =	pa11_dma_supported,
	.alloc_consistent =	pa11_dma_alloc_consistent,
	.alloc_noncoherent =	pa11_dma_alloc_consistent,
	.free_consistent =	pa11_dma_free_consistent,
	.map_single =		pa11_dma_map_single,
	.unmap_single =		pa11_dma_unmap_single,
	.map_sg =		pa11_dma_map_sg,
	.unmap_sg =		pa11_dma_unmap_sg,
	.dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
	.dma_sync_single_for_device = pa11_dma_sync_single_for_device,
	.dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
	.dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,
};

static void *fail_alloc_consistent(struct device *dev, size_t size,
				   dma_addr_t *dma_handle, gfp_t flag)
{
	return NULL;
}

static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size,
					  dma_addr_t *dma_handle, gfp_t flag)
{
	void *addr;

	addr = (void *)__get_free_pages(flag, get_order(size));
	if (addr)
		*dma_handle = (dma_addr_t)virt_to_phys(addr);

	return addr;
}

static void pa11_dma_free_noncoherent(struct device *dev, size_t size,
					void *vaddr, dma_addr_t iova)
{
	free_pages((unsigned long)vaddr, get_order(size));
	return;
}

struct hppa_dma_ops pcx_dma_ops = {
	.dma_supported =	pa11_dma_supported,
	.alloc_consistent =	fail_alloc_consistent,
	.alloc_noncoherent =	pa11_dma_alloc_noncoherent,
	.free_consistent =	pa11_dma_free_noncoherent,
	.map_single =		pa11_dma_map_single,
	.unmap_single =		pa11_dma_unmap_single,
	.map_sg =		pa11_dma_map_sg,
	.unmap_sg =		pa11_dma_unmap_sg,
	.dma_sync_single_for_cpu =	pa11_dma_sync_single_for_cpu,
	.dma_sync_single_for_device =	pa11_dma_sync_single_for_device,
	.dma_sync_sg_for_cpu =		pa11_dma_sync_sg_for_cpu,
	.dma_sync_sg_for_device =	pa11_dma_sync_sg_for_device,
};