arch/arm/include/asm/arch-s3c24x0/memory.h

/*
 * linux/include/asm-arm/arch-s3c2400/memory.h by garyj@denx.de
 * based on
 * linux/include/asm-arm/arch-sa1100/memory.h
 *
 * Copyright (c) 1999 Nicolas Pitre <nico@visuaide.com>
 */

#ifndef __ASM_ARCH_MEMORY_H
#define __ASM_ARCH_MEMORY_H


/*
 * Task size: 3GB
 */
#define TASK_SIZE       (0xc0000000UL)
#define TASK_SIZE_26	(0x04000000UL)

/*
 * This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define TASK_UNMAPPED_BASE (TASK_SIZE / 3)

/*
 * Page offset: 3GB
 */
#define PAGE_OFFSET     (0xc0000000UL)

/*
 * Physical DRAM offset is 0x0c000000 on the S3C2400
 */
#define PHYS_OFFSET	(0x0c000000UL)

/* Modified for S3C2400, by chc, 20010509 */
#define RAM_IN_BANK_0  32*1024*1024
#define RAM_IN_BANK_1  0
#define RAM_IN_BANK_2  0
#define RAM_IN_BANK_3  0

#define MEM_SIZE  (RAM_IN_BANK_0+RAM_IN_BANK_1+RAM_IN_BANK_2+RAM_IN_BANK_3)


/* translation macros */
#define __virt_to_phys__is_a_macro
#define __phys_to_virt__is_a_macro

#if (RAM_IN_BANK_1 + RAM_IN_BANK_2 + RAM_IN_BANK_3 == 0)

#define __virt_to_phys(x) ( (x) - PAGE_OFFSET + 0x0c000000 )
#define __phys_to_virt(x) ( (x) - 0x0c000000 + PAGE_OFFSET )

#elif (RAM_IN_BANK_0 == RAM_IN_BANK_1) && \
      (RAM_IN_BANK_2 + RAM_IN_BANK_3 == 0)

/* Two identical banks */
#define __virt_to_phys(x) \
	  ( ((x) < PAGE_OFFSET+RAM_IN_BANK_0) ? \
	    ((x) - PAGE_OFFSET + _DRAMBnk0) : \
	    ((x) - PAGE_OFFSET - RAM_IN_BANK_0 + _DRAMBnk1) )
#define __phys_to_virt(x) \
	  ( ((x)&0x07ffffff) + \
	    (((x)&0x08000000) ? PAGE_OFFSET+RAM_IN_BANK_0 : PAGE_OFFSET) )
#else

/* It's more efficient for all other cases to use the function call */
#undef __virt_to_phys__is_a_macro
#undef __phys_to_virt__is_a_macro
extern unsigned long __virt_to_phys(unsigned long vpage);
extern unsigned long __phys_to_virt(unsigned long ppage);

#endif

/*
 * Virtual view <-> DMA view memory address translations
 * virt_to_bus: Used to translate the virtual address to an
 *              address suitable to be passed to set_dma_addr
 * bus_to_virt: Used to convert an address for DMA operations
 *              to an address that the kernel can use.
 *
 * On the SA1100, bus addresses are equivalent to physical addresses.
 */
#define __virt_to_bus__is_a_macro
#define __virt_to_bus(x)        __virt_to_phys(x)
#define __bus_to_virt__is_a_macro
#define __bus_to_virt(x)        __phys_to_virt(x)


#ifdef CONFIG_DISCONTIGMEM
#error "CONFIG_DISCONTIGMEM will not work on S3C2400"
/*
 * Because of the wide memory address space between physical RAM banks on the
 * SA1100, it's much more convenient to use Linux's NUMA support to implement
 * our memory map representation.  Assuming all memory nodes have equal access
 * characteristics, we then have generic discontiguous memory support.
 *
 * Of course, all this isn't mandatory for SA1100 implementations with only
 * one used memory bank.  For those, simply undefine CONFIG_DISCONTIGMEM.
 *
 * The nodes are matched with the physical memory bank addresses which are
 * incidentally the same as virtual addresses.
 *
 *	node 0:  0xc0000000 - 0xc7ffffff
 *	node 1:  0xc8000000 - 0xcfffffff
 *	node 2:  0xd0000000 - 0xd7ffffff
 *	node 3:  0xd8000000 - 0xdfffffff
 */

#define NR_NODES	4

/*
 * Given a kernel address, find the home node of the underlying memory.
 */
#define KVADDR_TO_NID(addr) \
		(((unsigned long)(addr) - 0xc0000000) >> 27)

/*
 * Given a physical address, convert it to a node id.
 */
#define PHYS_TO_NID(addr) KVADDR_TO_NID(__phys_to_virt(addr))

/*
 * Given a kaddr, ADDR_TO_MAPBASE finds the owning node of the memory
 * and returns the mem_map of that node.
 */
#define ADDR_TO_MAPBASE(kaddr) \
			NODE_MEM_MAP(KVADDR_TO_NID((unsigned long)(kaddr)))

/*
 * Given a kaddr, LOCAL_MEM_MAP finds the owning node of the memory
 * and returns the index corresponding to the appropriate page in the
 * node's mem_map.
 */
#define LOCAL_MAP_NR(kvaddr) \
	(((unsigned long)(kvaddr) & 0x07ffffff) >> PAGE_SHIFT)

/*
 * Given a kaddr, virt_to_page returns a pointer to the corresponding
 * mem_map entry.
 */
#define virt_to_page(kaddr) \
	(ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))

/*
 * VALID_PAGE returns a non-zero value if given page pointer is valid.
 * This assumes all node's mem_maps are stored within the node they refer to.
 */
#define VALID_PAGE(page) \
({ unsigned int node = KVADDR_TO_NID(page); \
   ( (node < NR_NODES) && \
     ((unsigned)((page) - NODE_MEM_MAP(node)) < NODE_DATA(node)->node_size) ); \
})

#else

#define PHYS_TO_NID(addr)	(0)

#endif
#endif /* __ASM_ARCH_MEMORY_H */