arch/mips/sgi-ip27/ip27-memory.c - linux - Git at Google

 /*
  * 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.
  *
  * Copyright (C) 2000, 05 by Ralf Baechle (ralf@linux-mips.org)
  * Copyright (C) 2000 by Silicon Graphics, Inc.
  * Copyright (C) 2004 by Christoph Hellwig
  *
  * On SGI IP27 the ARC memory configuration data is completely bogus but
  * alternate easier to use mechanisms are available.
  */
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/memblock.h>
 #include <linux/mm.h>
 #include <linux/mmzone.h>
 #include <linux/export.h>
 #include <linux/nodemask.h>
 #include <linux/swap.h>
 #include <linux/pfn.h>
 #include <linux/highmem.h>
 #include <asm/page.h>
 #include <asm/pgalloc.h>
 #include <asm/sections.h>

 #include <asm/sn/arch.h>
 #include <asm/sn/agent.h>
 #include <asm/sn/klconfig.h>

 #include "ip27-common.h"

 #define SLOT_PFNSHIFT		(SLOT_SHIFT - PAGE_SHIFT)
 #define PFN_NASIDSHFT		(NASID_SHFT - PAGE_SHIFT)

 struct node_data *__node_data[MAX_NUMNODES];

 EXPORT_SYMBOL(__node_data);

 static u64 gen_region_mask(void)
 {
 	int region_shift;
 	u64 region_mask;
 	nasid_t nasid;

 	region_shift = get_region_shift();
 	region_mask = 0;
 	for_each_online_node(nasid)
 		region_mask |= BIT_ULL(nasid >> region_shift);

 	return region_mask;
 }

 #define rou_rflag	rou_flags

 static int router_distance;

 static void router_recurse(klrou_t *router_a, klrou_t *router_b, int depth)
 {
 	klrou_t *router;
 	lboard_t *brd;
 	int	port;

 	if (router_a->rou_rflag == 1)
 		return;

 	if (depth >= router_distance)
 		return;

 	router_a->rou_rflag = 1;

 	for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
 		if (router_a->rou_port[port].port_nasid == INVALID_NASID)
 			continue;

 		brd = (lboard_t *)NODE_OFFSET_TO_K0(
 			router_a->rou_port[port].port_nasid,
 			router_a->rou_port[port].port_offset);

 		if (brd->brd_type == KLTYPE_ROUTER) {
 			router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);
 			if (router == router_b) {
 				if (depth < router_distance)
 					router_distance = depth;
 			}
 			else
 				router_recurse(router, router_b, depth + 1);
 		}
 	}

 	router_a->rou_rflag = 0;
 }

 unsigned char __node_distances[MAX_NUMNODES][MAX_NUMNODES];
 EXPORT_SYMBOL(__node_distances);

 static int __init compute_node_distance(nasid_t nasid_a, nasid_t nasid_b)
 {
 	klrou_t *router, *router_a = NULL, *router_b = NULL;
 	lboard_t *brd, *dest_brd;
 	nasid_t nasid;
 	int port;

 	/* Figure out which routers nodes in question are connected to */
 	for_each_online_node(nasid) {
 		brd = find_lboard_class((lboard_t *)KL_CONFIG_INFO(nasid),
 					KLTYPE_ROUTER);

 		if (!brd)
 			continue;

 		do {
 			if (brd->brd_flags & DUPLICATE_BOARD)
 				continue;

 			router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);
 			router->rou_rflag = 0;

 			for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
 				if (router->rou_port[port].port_nasid == INVALID_NASID)
 					continue;

 				dest_brd = (lboard_t *)NODE_OFFSET_TO_K0(
 					router->rou_port[port].port_nasid,
 					router->rou_port[port].port_offset);

 				if (dest_brd->brd_type == KLTYPE_IP27) {
 					if (dest_brd->brd_nasid == nasid_a)
 						router_a = router;
 					if (dest_brd->brd_nasid == nasid_b)
 						router_b = router;
 				}
 			}

 		} while ((brd = find_lboard_class(KLCF_NEXT(brd), KLTYPE_ROUTER)));
 	}

 	if (nasid_a == nasid_b)
 		return LOCAL_DISTANCE;

 	if (router_a == router_b)
 		return LOCAL_DISTANCE + 1;

 	if (router_a == NULL) {
 		pr_info("node_distance: router_a NULL\n");
 		return 255;
 	}
 	if (router_b == NULL) {
 		pr_info("node_distance: router_b NULL\n");
 		return 255;
 	}

 	router_distance = 100;
 	router_recurse(router_a, router_b, 2);

 	return LOCAL_DISTANCE + router_distance;
 }

 static void __init init_topology_matrix(void)
 {
 	nasid_t row, col;

 	for (row = 0; row < MAX_NUMNODES; row++)
 		for (col = 0; col < MAX_NUMNODES; col++)
 			__node_distances[row][col] = -1;

 	for_each_online_node(row) {
 		for_each_online_node(col) {
 			__node_distances[row][col] =
 				compute_node_distance(row, col);
 		}
 	}
 }

 static void __init dump_topology(void)
 {
 	nasid_t nasid;
 	lboard_t *brd, *dest_brd;
 	int port;
 	int router_num = 0;
 	klrou_t *router;
 	nasid_t row, col;

 	pr_info("************** Topology ********************\n");

 	pr_info("    ");
 	for_each_online_node(col)
 		pr_cont("%02d ", col);
 	pr_cont("\n");
 	for_each_online_node(row) {
 		pr_info("%02d  ", row);
 		for_each_online_node(col)
 			pr_cont("%2d ", node_distance(row, col));
 		pr_cont("\n");
 	}

 	for_each_online_node(nasid) {
 		brd = find_lboard_class((lboard_t *)KL_CONFIG_INFO(nasid),
 					KLTYPE_ROUTER);

 		if (!brd)
 			continue;

 		do {
 			if (brd->brd_flags & DUPLICATE_BOARD)
 				continue;
 			pr_cont("Router %d:", router_num);
 			router_num++;

 			router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);

 			for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
 				if (router->rou_port[port].port_nasid == INVALID_NASID)
 					continue;

 				dest_brd = (lboard_t *)NODE_OFFSET_TO_K0(
 					router->rou_port[port].port_nasid,
 					router->rou_port[port].port_offset);

 				if (dest_brd->brd_type == KLTYPE_IP27)
 					pr_cont(" %d", dest_brd->brd_nasid);
 				if (dest_brd->brd_type == KLTYPE_ROUTER)
 					pr_cont(" r");
 			}
 			pr_cont("\n");

 		} while ( (brd = find_lboard_class(KLCF_NEXT(brd), KLTYPE_ROUTER)) );
 	}
 }

 static unsigned long __init slot_getbasepfn(nasid_t nasid, int slot)
 {
 	return ((unsigned long)nasid << PFN_NASIDSHFT) | (slot << SLOT_PFNSHIFT);
 }

 static unsigned long __init slot_psize_compute(nasid_t nasid, int slot)
 {
 	lboard_t *brd;
 	klmembnk_t *banks;
 	unsigned long size;

 	/* Find the node board */
 	brd = find_lboard((lboard_t *)KL_CONFIG_INFO(nasid), KLTYPE_IP27);
 	if (!brd)
 		return 0;

 	/* Get the memory bank structure */
 	banks = (klmembnk_t *) find_first_component(brd, KLSTRUCT_MEMBNK);
 	if (!banks)
 		return 0;

 	/* Size in _Megabytes_ */
 	size = (unsigned long)banks->membnk_bnksz[slot/4];

 	/* hack for 128 dimm banks */
 	if (size <= 128) {
 		if (slot % 4 == 0) {
 			size <<= 20;		/* size in bytes */
 			return size >> PAGE_SHIFT;
 		} else
 			return 0;
 	} else {
 		size /= 4;
 		size <<= 20;
 		return size >> PAGE_SHIFT;
 	}
 }

 static void __init mlreset(void)
 {
 	u64 region_mask;
 	nasid_t nasid;

 	master_nasid = get_nasid();

 	/*
 	 * Probe for all CPUs - this creates the cpumask and sets up the
 	 * mapping tables.  We need to do this as early as possible.
 	 */
 #ifdef CONFIG_SMP
 	cpu_node_probe();
 #endif

 	init_topology_matrix();
 	dump_topology();

 	region_mask = gen_region_mask();

 	setup_replication_mask();

 	/*
 	 * Set all nodes' calias sizes to 8k
 	 */
 	for_each_online_node(nasid) {
 		/*
 		 * Always have node 0 in the region mask, otherwise
 		 * CALIAS accesses get exceptions since the hub
 		 * thinks it is a node 0 address.
 		 */
 		REMOTE_HUB_S(nasid, PI_REGION_PRESENT, (region_mask | 1));
 		REMOTE_HUB_S(nasid, PI_CALIAS_SIZE, PI_CALIAS_SIZE_0);

 #ifdef LATER
 		/*
 		 * Set up all hubs to have a big window pointing at
 		 * widget 0. Memory mode, widget 0, offset 0
 		 */
 		REMOTE_HUB_S(nasid, IIO_ITTE(SWIN0_BIGWIN),
 			((HUB_PIO_MAP_TO_MEM << IIO_ITTE_IOSP_SHIFT) |
 			(0 << IIO_ITTE_WIDGET_SHIFT)));
 #endif
 	}
 }

 static void __init szmem(void)
 {
 	unsigned long slot_psize, slot0sz = 0, nodebytes;	/* Hack to detect problem configs */
 	int slot;
 	nasid_t node;

 	for_each_online_node(node) {
 		nodebytes = 0;
 		for (slot = 0; slot < MAX_MEM_SLOTS; slot++) {
 			slot_psize = slot_psize_compute(node, slot);
 			if (slot == 0)
 				slot0sz = slot_psize;
 			/*
 			 * We need to refine the hack when we have replicated
 			 * kernel text.
 			 */
 			nodebytes += (1LL << SLOT_SHIFT);

 			if (!slot_psize)
 				continue;

 			if ((nodebytes >> PAGE_SHIFT) * (sizeof(struct page)) >
 						(slot0sz << PAGE_SHIFT)) {
 				pr_info("Ignoring slot %d onwards on node %d\n",
 								slot, node);
 				slot = MAX_MEM_SLOTS;
 				continue;
 			}
 			memblock_add_node(PFN_PHYS(slot_getbasepfn(node, slot)),
 					  PFN_PHYS(slot_psize), node);
 		}
 	}
 }

 static void __init node_mem_init(nasid_t node)
 {
 	unsigned long slot_firstpfn = slot_getbasepfn(node, 0);
 	unsigned long slot_freepfn = node_getfirstfree(node);
 	unsigned long start_pfn, end_pfn;

 	get_pfn_range_for_nid(node, &start_pfn, &end_pfn);

 	/*
 	 * Allocate the node data structures on the node first.
 	 */
 	__node_data[node] = __va(slot_freepfn << PAGE_SHIFT);
 	memset(__node_data[node], 0, PAGE_SIZE);

 	NODE_DATA(node)->node_start_pfn = start_pfn;
 	NODE_DATA(node)->node_spanned_pages = end_pfn - start_pfn;

 	cpumask_clear(&hub_data(node)->h_cpus);

 	slot_freepfn += PFN_UP(sizeof(struct pglist_data) +
 			       sizeof(struct hub_data));

 	memblock_reserve(slot_firstpfn << PAGE_SHIFT,
 			 ((slot_freepfn - slot_firstpfn) << PAGE_SHIFT));
 }

 /*
  * A node with nothing.	 We use it to avoid any special casing in
  * cpumask_of_node
  */
 static struct node_data null_node = {
 	.hub = {
 		.h_cpus = CPU_MASK_NONE
 	}
 };

 /*
  * Currently, the intranode memory hole support assumes that each slot
  * contains at least 32 MBytes of memory. We assume all bootmem data
  * fits on the first slot.
  */
 void __init prom_meminit(void)
 {
 	nasid_t node;

 	mlreset();
 	szmem();
 	max_low_pfn = PHYS_PFN(memblock_end_of_DRAM());

 	for (node = 0; node < MAX_NUMNODES; node++) {
 		if (node_online(node)) {
 			node_mem_init(node);
 			continue;
 		}
 		__node_data[node] = &null_node;
 	}

 	memblocks_present();
 }

 void __init prom_free_prom_memory(void)
 {
 	/* We got nothing to free here ...  */
 }

 extern void setup_zero_pages(void);

 void __init paging_init(void)
 {
 	unsigned long zones_size[MAX_NR_ZONES] = {0, };

 	pagetable_init();
 	zones_size[ZONE_NORMAL] = max_low_pfn;
 	free_area_init(zones_size);
 }

 void __init mem_init(void)
 {
 	high_memory = (void *) __va(get_num_physpages() << PAGE_SHIFT);
 	memblock_free_all();
 	setup_zero_pages();	/* This comes from node 0 */
 	mem_init_print_info(NULL);
 }
	/*
	* 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.
	*
	* Copyright (C) 2000, 05 by Ralf Baechle (ralf@linux-mips.org)
	* Copyright (C) 2000 by Silicon Graphics, Inc.
	* Copyright (C) 2004 by Christoph Hellwig
	*
	* On SGI IP27 the ARC memory configuration data is completely bogus but
	* alternate easier to use mechanisms are available.
	*/
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/memblock.h>
	#include <linux/mm.h>
	#include <linux/mmzone.h>
	#include <linux/export.h>
	#include <linux/nodemask.h>
	#include <linux/swap.h>
	#include <linux/pfn.h>
	#include <linux/highmem.h>
	#include <asm/page.h>
	#include <asm/pgalloc.h>
	#include <asm/sections.h>

	#include <asm/sn/arch.h>
	#include <asm/sn/agent.h>
	#include <asm/sn/klconfig.h>

	#include "ip27-common.h"

	#define SLOT_PFNSHIFT (SLOT_SHIFT - PAGE_SHIFT)
	#define PFN_NASIDSHFT (NASID_SHFT - PAGE_SHIFT)

	struct node_data *__node_data[MAX_NUMNODES];

	EXPORT_SYMBOL(__node_data);

	static u64 gen_region_mask(void)
	{
	int region_shift;
	u64 region_mask;
	nasid_t nasid;

	region_shift = get_region_shift();
	region_mask = 0;
	for_each_online_node(nasid)
	region_mask \|= BIT_ULL(nasid >> region_shift);

	return region_mask;
	}

	#define rou_rflag rou_flags

	static int router_distance;

	static void router_recurse(klrou_t router_a, klrou_t router_b, int depth)
	{
	klrou_t *router;
	lboard_t *brd;
	int port;

	if (router_a->rou_rflag == 1)
	return;

	if (depth >= router_distance)
	return;

	router_a->rou_rflag = 1;

	for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
	if (router_a->rou_port[port].port_nasid == INVALID_NASID)
	continue;

	brd = (lboard_t *)NODE_OFFSET_TO_K0(
	router_a->rou_port[port].port_nasid,
	router_a->rou_port[port].port_offset);

	if (brd->brd_type == KLTYPE_ROUTER) {
	router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);
	if (router == router_b) {
	if (depth < router_distance)
	router_distance = depth;
	}
	else
	router_recurse(router, router_b, depth + 1);
	}
	}

	router_a->rou_rflag = 0;
	}

	unsigned char __node_distances[MAX_NUMNODES][MAX_NUMNODES];
	EXPORT_SYMBOL(__node_distances);

	static int __init compute_node_distance(nasid_t nasid_a, nasid_t nasid_b)
	{
	klrou_t router, router_a = NULL, *router_b = NULL;
	lboard_t brd, dest_brd;
	nasid_t nasid;
	int port;

	/* Figure out which routers nodes in question are connected to */
	for_each_online_node(nasid) {
	brd = find_lboard_class((lboard_t *)KL_CONFIG_INFO(nasid),
	KLTYPE_ROUTER);

	if (!brd)
	continue;

	do {
	if (brd->brd_flags & DUPLICATE_BOARD)
	continue;

	router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);
	router->rou_rflag = 0;

	for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
	if (router->rou_port[port].port_nasid == INVALID_NASID)
	continue;

	dest_brd = (lboard_t *)NODE_OFFSET_TO_K0(
	router->rou_port[port].port_nasid,
	router->rou_port[port].port_offset);

	if (dest_brd->brd_type == KLTYPE_IP27) {
	if (dest_brd->brd_nasid == nasid_a)
	router_a = router;
	if (dest_brd->brd_nasid == nasid_b)
	router_b = router;
	}
	}

	} while ((brd = find_lboard_class(KLCF_NEXT(brd), KLTYPE_ROUTER)));
	}

	if (nasid_a == nasid_b)
	return LOCAL_DISTANCE;

	if (router_a == router_b)
	return LOCAL_DISTANCE + 1;

	if (router_a == NULL) {
	pr_info("node_distance: router_a NULL\n");
	return 255;
	}
	if (router_b == NULL) {
	pr_info("node_distance: router_b NULL\n");
	return 255;
	}

	router_distance = 100;
	router_recurse(router_a, router_b, 2);

	return LOCAL_DISTANCE + router_distance;
	}

	static void __init init_topology_matrix(void)
	{
	nasid_t row, col;

	for (row = 0; row < MAX_NUMNODES; row++)
	for (col = 0; col < MAX_NUMNODES; col++)
	__node_distances[row][col] = -1;

	for_each_online_node(row) {
	for_each_online_node(col) {
	__node_distances[row][col] =
	compute_node_distance(row, col);
	}
	}
	}

	static void __init dump_topology(void)
	{
	nasid_t nasid;
	lboard_t brd, dest_brd;
	int port;
	int router_num = 0;
	klrou_t *router;
	nasid_t row, col;

	pr_info("************ Topology ******************\n");

	pr_info(" ");
	for_each_online_node(col)
	pr_cont("%02d ", col);
	pr_cont("\n");
	for_each_online_node(row) {
	pr_info("%02d ", row);
	for_each_online_node(col)
	pr_cont("%2d ", node_distance(row, col));
	pr_cont("\n");
	}

	for_each_online_node(nasid) {
	brd = find_lboard_class((lboard_t *)KL_CONFIG_INFO(nasid),
	KLTYPE_ROUTER);

	if (!brd)
	continue;

	do {
	if (brd->brd_flags & DUPLICATE_BOARD)
	continue;
	pr_cont("Router %d:", router_num);
	router_num++;

	router = (klrou_t *)NODE_OFFSET_TO_K0(NASID_GET(brd), brd->brd_compts[0]);

	for (port = 1; port <= MAX_ROUTER_PORTS; port++) {
	if (router->rou_port[port].port_nasid == INVALID_NASID)
	continue;

	dest_brd = (lboard_t *)NODE_OFFSET_TO_K0(
	router->rou_port[port].port_nasid,
	router->rou_port[port].port_offset);

	if (dest_brd->brd_type == KLTYPE_IP27)
	pr_cont(" %d", dest_brd->brd_nasid);
	if (dest_brd->brd_type == KLTYPE_ROUTER)
	pr_cont(" r");
	}
	pr_cont("\n");

	} while ( (brd = find_lboard_class(KLCF_NEXT(brd), KLTYPE_ROUTER)) );
	}
	}

	static unsigned long __init slot_getbasepfn(nasid_t nasid, int slot)
	{
	return ((unsigned long)nasid << PFN_NASIDSHFT) \| (slot << SLOT_PFNSHIFT);
	}

	static unsigned long __init slot_psize_compute(nasid_t nasid, int slot)
	{
	lboard_t *brd;
	klmembnk_t *banks;
	unsigned long size;

	/* Find the node board */
	brd = find_lboard((lboard_t *)KL_CONFIG_INFO(nasid), KLTYPE_IP27);
	if (!brd)
	return 0;

	/* Get the memory bank structure */
	banks = (klmembnk_t *) find_first_component(brd, KLSTRUCT_MEMBNK);
	if (!banks)
	return 0;

	/* Size in _Megabytes_ */
	size = (unsigned long)banks->membnk_bnksz[slot/4];

	/* hack for 128 dimm banks */
	if (size <= 128) {
	if (slot % 4 == 0) {
	size <<= 20; /* size in bytes */
	return size >> PAGE_SHIFT;
	} else
	return 0;
	} else {
	size /= 4;
	size <<= 20;
	return size >> PAGE_SHIFT;
	}
	}

	static void __init mlreset(void)
	{
	u64 region_mask;
	nasid_t nasid;

	master_nasid = get_nasid();

	/*
	* Probe for all CPUs - this creates the cpumask and sets up the
	* mapping tables. We need to do this as early as possible.
	*/
	#ifdef CONFIG_SMP
	cpu_node_probe();
	#endif

	init_topology_matrix();
	dump_topology();

	region_mask = gen_region_mask();

	setup_replication_mask();

	/*
	* Set all nodes' calias sizes to 8k
	*/
	for_each_online_node(nasid) {
	/*
	* Always have node 0 in the region mask, otherwise
	* CALIAS accesses get exceptions since the hub
	* thinks it is a node 0 address.
	*/
	REMOTE_HUB_S(nasid, PI_REGION_PRESENT, (region_mask \| 1));
	REMOTE_HUB_S(nasid, PI_CALIAS_SIZE, PI_CALIAS_SIZE_0);

	#ifdef LATER
	/*
	* Set up all hubs to have a big window pointing at
	* widget 0. Memory mode, widget 0, offset 0
	*/
	REMOTE_HUB_S(nasid, IIO_ITTE(SWIN0_BIGWIN),
	((HUB_PIO_MAP_TO_MEM << IIO_ITTE_IOSP_SHIFT) \|
	(0 << IIO_ITTE_WIDGET_SHIFT)));
	#endif
	}
	}

	static void __init szmem(void)
	{
	unsigned long slot_psize, slot0sz = 0, nodebytes; /* Hack to detect problem configs */
	int slot;
	nasid_t node;

	for_each_online_node(node) {
	nodebytes = 0;
	for (slot = 0; slot < MAX_MEM_SLOTS; slot++) {
	slot_psize = slot_psize_compute(node, slot);
	if (slot == 0)
	slot0sz = slot_psize;
	/*
	* We need to refine the hack when we have replicated
	* kernel text.
	*/
	nodebytes += (1LL << SLOT_SHIFT);

	if (!slot_psize)
	continue;

	if ((nodebytes >> PAGE_SHIFT) * (sizeof(struct page)) >
	(slot0sz << PAGE_SHIFT)) {
	pr_info("Ignoring slot %d onwards on node %d\n",
	slot, node);
	slot = MAX_MEM_SLOTS;
	continue;
	}
	memblock_add_node(PFN_PHYS(slot_getbasepfn(node, slot)),
	PFN_PHYS(slot_psize), node);
	}
	}
	}

	static void __init node_mem_init(nasid_t node)
	{
	unsigned long slot_firstpfn = slot_getbasepfn(node, 0);
	unsigned long slot_freepfn = node_getfirstfree(node);
	unsigned long start_pfn, end_pfn;

	get_pfn_range_for_nid(node, &start_pfn, &end_pfn);

	/*
	* Allocate the node data structures on the node first.
	*/
	__node_data[node] = __va(slot_freepfn << PAGE_SHIFT);
	memset(__node_data[node], 0, PAGE_SIZE);

	NODE_DATA(node)->node_start_pfn = start_pfn;
	NODE_DATA(node)->node_spanned_pages = end_pfn - start_pfn;

	cpumask_clear(&hub_data(node)->h_cpus);

	slot_freepfn += PFN_UP(sizeof(struct pglist_data) +
	sizeof(struct hub_data));

	memblock_reserve(slot_firstpfn << PAGE_SHIFT,
	((slot_freepfn - slot_firstpfn) << PAGE_SHIFT));
	}

	/*
	* A node with nothing. We use it to avoid any special casing in
	* cpumask_of_node
	*/
	static struct node_data null_node = {
	.hub = {
	.h_cpus = CPU_MASK_NONE
	}
	};

	/*
	* Currently, the intranode memory hole support assumes that each slot
	* contains at least 32 MBytes of memory. We assume all bootmem data
	* fits on the first slot.
	*/
	void __init prom_meminit(void)
	{
	nasid_t node;

	mlreset();
	szmem();
	max_low_pfn = PHYS_PFN(memblock_end_of_DRAM());

	for (node = 0; node < MAX_NUMNODES; node++) {
	if (node_online(node)) {
	node_mem_init(node);
	continue;
	}
	__node_data[node] = &null_node;
	}

	memblocks_present();
	}

	void __init prom_free_prom_memory(void)
	{
	/* We got nothing to free here ... */
	}

	extern void setup_zero_pages(void);

	void __init paging_init(void)
	{
	unsigned long zones_size[MAX_NR_ZONES] = {0, };

	pagetable_init();
	zones_size[ZONE_NORMAL] = max_low_pfn;
	free_area_init(zones_size);
	}

	void __init mem_init(void)
	{
	high_memory = (void *) __va(get_num_physpages() << PAGE_SHIFT);
	memblock_free_all();
	setup_zero_pages(); /* This comes from node 0 */
	mem_init_print_info(NULL);
	}