nios2: I/O Mapping
This patch adds several definitions for I/O accessors and ioremap(). Signed-off-by: Ley Foon Tan <lftan@altera.com>
This commit is contained in:
		
							parent
							
								
									5ccc6af5e8
								
							
						
					
					
						commit
						6b8baec4d6
					
				
							
								
								
									
										61
									
								
								arch/nios2/include/asm/io.h
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										61
									
								
								arch/nios2/include/asm/io.h
									
									
									
									
									
										Normal file
									
								
							| @ -0,0 +1,61 @@ | ||||
| /*
 | ||||
|  * Copyright (C) 2014 Altera Corporation | ||||
|  * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> | ||||
|  * Copyright (C) 2004 Microtronix Datacom Ltd. | ||||
|  * | ||||
|  * This file is subject to the terms and conditions of the GNU General Public | ||||
|  * License. See the file "COPYING" in the main directory of this archive | ||||
|  * for more details. | ||||
|  */ | ||||
| 
 | ||||
| #ifndef _ASM_NIOS2_IO_H | ||||
| #define _ASM_NIOS2_IO_H | ||||
| 
 | ||||
| #include <asm/pgtable-bits.h> | ||||
| #include <asm-generic/iomap.h> | ||||
| 
 | ||||
| /* PCI is not supported in nios2, set this to 0. */ | ||||
| #define IO_SPACE_LIMIT 0 | ||||
| 
 | ||||
| #define readb_relaxed(addr)	readb(addr) | ||||
| #define readw_relaxed(addr)	readw(addr) | ||||
| #define readl_relaxed(addr)	readl(addr) | ||||
| 
 | ||||
| #define writeb_relaxed(x, addr)	writeb(x, addr) | ||||
| #define writew_relaxed(x, addr)	writew(x, addr) | ||||
| #define writel_relaxed(x, addr)	writel(x, addr) | ||||
| 
 | ||||
| #include <asm-generic/io.h> | ||||
| 
 | ||||
| extern void __iomem *__ioremap(unsigned long physaddr, unsigned long size, | ||||
| 			unsigned long cacheflag); | ||||
| extern void __iounmap(void __iomem *addr); | ||||
| 
 | ||||
| static inline void __iomem *ioremap(unsigned long physaddr, unsigned long size) | ||||
| { | ||||
| 	return __ioremap(physaddr, size, 0); | ||||
| } | ||||
| 
 | ||||
| static inline void __iomem *ioremap_nocache(unsigned long physaddr, | ||||
| 						unsigned long size) | ||||
| { | ||||
| 	return __ioremap(physaddr, size, 0); | ||||
| } | ||||
| 
 | ||||
| static inline void iounmap(void __iomem *addr) | ||||
| { | ||||
| 	__iounmap(addr); | ||||
| } | ||||
| 
 | ||||
| /* Pages to physical address... */ | ||||
| # define page_to_phys(page)	virt_to_phys(page_to_virt(page)) | ||||
| # define page_to_bus(page)	page_to_virt(page) | ||||
| 
 | ||||
| /* Macros used for converting between virtual and physical mappings. */ | ||||
| # define phys_to_virt(vaddr)	\ | ||||
| 	((void *)((unsigned long)(vaddr) | CONFIG_NIOS2_KERNEL_REGION_BASE)) | ||||
| /* Clear top 3 bits */ | ||||
| # define virt_to_phys(vaddr)	\ | ||||
| 	((unsigned long)((unsigned long)(vaddr) & ~0xE0000000)) | ||||
| 
 | ||||
| #endif /* _ASM_NIOS2_IO_H */ | ||||
							
								
								
									
										187
									
								
								arch/nios2/mm/ioremap.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										187
									
								
								arch/nios2/mm/ioremap.c
									
									
									
									
									
										Normal file
									
								
							| @ -0,0 +1,187 @@ | ||||
| /*
 | ||||
|  * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> | ||||
|  * Copyright (C) 2009 Wind River Systems Inc | ||||
|  *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com | ||||
|  * Copyright (C) 2004 Microtronix Datacom Ltd. | ||||
|  * | ||||
|  * This file is subject to the terms and conditions of the GNU General Public | ||||
|  * License. See the file "COPYING" in the main directory of this archive | ||||
|  * for more details. | ||||
|  */ | ||||
| 
 | ||||
| #include <linux/export.h> | ||||
| #include <linux/sched.h> | ||||
| #include <linux/mm.h> | ||||
| #include <linux/slab.h> | ||||
| #include <linux/vmalloc.h> | ||||
| #include <linux/io.h> | ||||
| 
 | ||||
| #include <asm/cacheflush.h> | ||||
| #include <asm/tlbflush.h> | ||||
| 
 | ||||
| static inline void remap_area_pte(pte_t *pte, unsigned long address, | ||||
| 				unsigned long size, unsigned long phys_addr, | ||||
| 				unsigned long flags) | ||||
| { | ||||
| 	unsigned long end; | ||||
| 	unsigned long pfn; | ||||
| 	pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_READ | ||||
| 				| _PAGE_WRITE | flags); | ||||
| 
 | ||||
| 	address &= ~PMD_MASK; | ||||
| 	end = address + size; | ||||
| 	if (end > PMD_SIZE) | ||||
| 		end = PMD_SIZE; | ||||
| 	if (address >= end) | ||||
| 		BUG(); | ||||
| 	pfn = PFN_DOWN(phys_addr); | ||||
| 	do { | ||||
| 		if (!pte_none(*pte)) { | ||||
| 			pr_err("remap_area_pte: page already exists\n"); | ||||
| 			BUG(); | ||||
| 		} | ||||
| 		set_pte(pte, pfn_pte(pfn, pgprot)); | ||||
| 		address += PAGE_SIZE; | ||||
| 		pfn++; | ||||
| 		pte++; | ||||
| 	} while (address && (address < end)); | ||||
| } | ||||
| 
 | ||||
| static inline int remap_area_pmd(pmd_t *pmd, unsigned long address, | ||||
| 				unsigned long size, unsigned long phys_addr, | ||||
| 				unsigned long flags) | ||||
| { | ||||
| 	unsigned long end; | ||||
| 
 | ||||
| 	address &= ~PGDIR_MASK; | ||||
| 	end = address + size; | ||||
| 	if (end > PGDIR_SIZE) | ||||
| 		end = PGDIR_SIZE; | ||||
| 	phys_addr -= address; | ||||
| 	if (address >= end) | ||||
| 		BUG(); | ||||
| 	do { | ||||
| 		pte_t *pte = pte_alloc_kernel(pmd, address); | ||||
| 
 | ||||
| 		if (!pte) | ||||
| 			return -ENOMEM; | ||||
| 		remap_area_pte(pte, address, end - address, address + phys_addr, | ||||
| 			flags); | ||||
| 		address = (address + PMD_SIZE) & PMD_MASK; | ||||
| 		pmd++; | ||||
| 	} while (address && (address < end)); | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int remap_area_pages(unsigned long address, unsigned long phys_addr, | ||||
| 				unsigned long size, unsigned long flags) | ||||
| { | ||||
| 	int error; | ||||
| 	pgd_t *dir; | ||||
| 	unsigned long end = address + size; | ||||
| 
 | ||||
| 	phys_addr -= address; | ||||
| 	dir = pgd_offset(&init_mm, address); | ||||
| 	flush_cache_all(); | ||||
| 	if (address >= end) | ||||
| 		BUG(); | ||||
| 	do { | ||||
| 		pud_t *pud; | ||||
| 		pmd_t *pmd; | ||||
| 
 | ||||
| 		error = -ENOMEM; | ||||
| 		pud = pud_alloc(&init_mm, dir, address); | ||||
| 		if (!pud) | ||||
| 			break; | ||||
| 		pmd = pmd_alloc(&init_mm, pud, address); | ||||
| 		if (!pmd) | ||||
| 			break; | ||||
| 		if (remap_area_pmd(pmd, address, end - address, | ||||
| 			phys_addr + address, flags)) | ||||
| 			break; | ||||
| 		error = 0; | ||||
| 		address = (address + PGDIR_SIZE) & PGDIR_MASK; | ||||
| 		dir++; | ||||
| 	} while (address && (address < end)); | ||||
| 	flush_tlb_all(); | ||||
| 	return error; | ||||
| } | ||||
| 
 | ||||
| #define IS_MAPPABLE_UNCACHEABLE(addr) (addr < 0x20000000UL) | ||||
| 
 | ||||
| /*
 | ||||
|  * Map some physical address range into the kernel address space. | ||||
|  */ | ||||
| void __iomem *__ioremap(unsigned long phys_addr, unsigned long size, | ||||
| 			unsigned long cacheflag) | ||||
| { | ||||
| 	struct vm_struct *area; | ||||
| 	unsigned long offset; | ||||
| 	unsigned long last_addr; | ||||
| 	void *addr; | ||||
| 
 | ||||
| 	/* Don't allow wraparound or zero size */ | ||||
| 	last_addr = phys_addr + size - 1; | ||||
| 
 | ||||
| 	if (!size || last_addr < phys_addr) | ||||
| 		return NULL; | ||||
| 
 | ||||
| 	/* Don't allow anybody to remap normal RAM that we're using */ | ||||
| 	if (phys_addr > PHYS_OFFSET && phys_addr < virt_to_phys(high_memory)) { | ||||
| 		char *t_addr, *t_end; | ||||
| 		struct page *page; | ||||
| 
 | ||||
| 		t_addr = __va(phys_addr); | ||||
| 		t_end = t_addr + (size - 1); | ||||
| 		for (page = virt_to_page(t_addr); | ||||
| 			page <= virt_to_page(t_end); page++) | ||||
| 			if (!PageReserved(page)) | ||||
| 				return NULL; | ||||
| 	} | ||||
| 
 | ||||
| 	/*
 | ||||
| 	 * Map uncached objects in the low part of address space to | ||||
| 	 * CONFIG_NIOS2_IO_REGION_BASE | ||||
| 	 */ | ||||
| 	if (IS_MAPPABLE_UNCACHEABLE(phys_addr) && | ||||
| 	    IS_MAPPABLE_UNCACHEABLE(last_addr) && | ||||
| 	    !(cacheflag & _PAGE_CACHED)) | ||||
| 		return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE + phys_addr); | ||||
| 
 | ||||
| 	/* Mappings have to be page-aligned */ | ||||
| 	offset = phys_addr & ~PAGE_MASK; | ||||
| 	phys_addr &= PAGE_MASK; | ||||
| 	size = PAGE_ALIGN(last_addr + 1) - phys_addr; | ||||
| 
 | ||||
| 	/* Ok, go for it */ | ||||
| 	area = get_vm_area(size, VM_IOREMAP); | ||||
| 	if (!area) | ||||
| 		return NULL; | ||||
| 	addr = area->addr; | ||||
| 	if (remap_area_pages((unsigned long) addr, phys_addr, size, | ||||
| 		cacheflag)) { | ||||
| 		vunmap(addr); | ||||
| 		return NULL; | ||||
| 	} | ||||
| 	return (void __iomem *) (offset + (char *)addr); | ||||
| } | ||||
| EXPORT_SYMBOL(__ioremap); | ||||
| 
 | ||||
| /*
 | ||||
|  * __iounmap unmaps nearly everything, so be careful | ||||
|  * it doesn't free currently pointer/page tables anymore but it | ||||
|  * wasn't used anyway and might be added later. | ||||
|  */ | ||||
| void __iounmap(void __iomem *addr) | ||||
| { | ||||
| 	struct vm_struct *p; | ||||
| 
 | ||||
| 	if ((unsigned long) addr > CONFIG_NIOS2_IO_REGION_BASE) | ||||
| 		return; | ||||
| 
 | ||||
| 	p = remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr)); | ||||
| 	if (!p) | ||||
| 		pr_err("iounmap: bad address %p\n", addr); | ||||
| 	kfree(p); | ||||
| } | ||||
| EXPORT_SYMBOL(__iounmap); | ||||
		Loading…
	
		Reference in New Issue
	
	Block a user