alistair23-linux/arch/tile/kernel/setup.c

/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation, version 2.
 *
 *   This program is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 */

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mmzone.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <linux/node.h>
#include <linux/cpu.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/kexec.h>
#include <linux/pci.h>
#include <linux/swiotlb.h>
#include <linux/initrd.h>
#include <linux/io.h>
#include <linux/highmem.h>
#include <linux/smp.h>
#include <linux/timex.h>
#include <linux/hugetlb.h>
#include <linux/start_kernel.h>
#include <linux/screen_info.h>
#include <linux/tick.h>
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/cacheflush.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <hv/hypervisor.h>
#include <arch/interrupts.h>

/* <linux/smp.h> doesn't provide this definition. */
#ifndef CONFIG_SMP
#define setup_max_cpus 1
#endif

static inline int ABS(int x) { return x >= 0 ? x : -x; }

/* Chip information */
char chip_model[64] __ro_after_init;

#ifdef CONFIG_VT
struct screen_info screen_info;
#endif

struct pglist_data node_data[MAX_NUMNODES] __read_mostly;
EXPORT_SYMBOL(node_data);

/* Information on the NUMA nodes that we compute early */
unsigned long node_start_pfn[MAX_NUMNODES];
unsigned long node_end_pfn[MAX_NUMNODES];
unsigned long __initdata node_memmap_pfn[MAX_NUMNODES];
unsigned long __initdata node_percpu_pfn[MAX_NUMNODES];
unsigned long __initdata node_free_pfn[MAX_NUMNODES];

static unsigned long __initdata node_percpu[MAX_NUMNODES];

/*
 * per-CPU stack and boot info.
 */
DEFINE_PER_CPU(unsigned long, boot_sp) =
	(unsigned long)init_stack + THREAD_SIZE - STACK_TOP_DELTA;

#ifdef CONFIG_SMP
DEFINE_PER_CPU(unsigned long, boot_pc) = (unsigned long)start_kernel;
#else
/*
 * The variable must be __initdata since it references __init code.
 * With CONFIG_SMP it is per-cpu data, which is exempt from validation.
 */
unsigned long __initdata boot_pc = (unsigned long)start_kernel;
#endif

#ifdef CONFIG_HIGHMEM
/* Page frame index of end of lowmem on each controller. */
unsigned long node_lowmem_end_pfn[MAX_NUMNODES];

/* Number of pages that can be mapped into lowmem. */
static unsigned long __initdata mappable_physpages;
#endif

/* Data on which physical memory controller corresponds to which NUMA node */
int node_controller[MAX_NUMNODES] = { [0 ... MAX_NUMNODES-1] = -1 };

#ifdef CONFIG_HIGHMEM
/* Map information from VAs to PAs */
unsigned long pbase_map[1 << (32 - HPAGE_SHIFT)]
  __ro_after_init __attribute__((aligned(L2_CACHE_BYTES)));
EXPORT_SYMBOL(pbase_map);

/* Map information from PAs to VAs */
void *vbase_map[NR_PA_HIGHBIT_VALUES]
  __ro_after_init __attribute__((aligned(L2_CACHE_BYTES)));
EXPORT_SYMBOL(vbase_map);
#endif

/* Node number as a function of the high PA bits */
int highbits_to_node[NR_PA_HIGHBIT_VALUES] __ro_after_init;
EXPORT_SYMBOL(highbits_to_node);

static unsigned int __initdata maxmem_pfn = -1U;
static unsigned int __initdata maxnodemem_pfn[MAX_NUMNODES] = {
	[0 ... MAX_NUMNODES-1] = -1U
};
static nodemask_t __initdata isolnodes;

#if defined(CONFIG_PCI) && !defined(__tilegx__)
enum { DEFAULT_PCI_RESERVE_MB = 64 };
static unsigned int __initdata pci_reserve_mb = DEFAULT_PCI_RESERVE_MB;
unsigned long __initdata pci_reserve_start_pfn = -1U;
unsigned long __initdata pci_reserve_end_pfn = -1U;
#endif

static int __init setup_maxmem(char *str)
{
	unsigned long long maxmem;
	if (str == NULL || (maxmem = memparse(str, NULL)) == 0)
		return -EINVAL;

	maxmem_pfn = (maxmem >> HPAGE_SHIFT) << (HPAGE_SHIFT - PAGE_SHIFT);
	pr_info("Forcing RAM used to no more than %dMB\n",
		maxmem_pfn >> (20 - PAGE_SHIFT));
	return 0;
}
early_param("maxmem", setup_maxmem);

static int __init setup_maxnodemem(char *str)
{
	char *endp;
	unsigned long long maxnodemem;
	long node;

	node = str ? simple_strtoul(str, &endp, 0) : INT_MAX;
	if (node >= MAX_NUMNODES || *endp != ':')
		return -EINVAL;

	maxnodemem = memparse(endp+1, NULL);
	maxnodemem_pfn[node] = (maxnodemem >> HPAGE_SHIFT) <<
		(HPAGE_SHIFT - PAGE_SHIFT);
	pr_info("Forcing RAM used on node %ld to no more than %dMB\n",
		node, maxnodemem_pfn[node] >> (20 - PAGE_SHIFT));
	return 0;
}
early_param("maxnodemem", setup_maxnodemem);

struct memmap_entry {
	u64 addr;	/* start of memory segment */
	u64 size;	/* size of memory segment */
};
static struct memmap_entry memmap_map[64];
static int memmap_nr;

static void add_memmap_region(u64 addr, u64 size)
{
	if (memmap_nr >= ARRAY_SIZE(memmap_map)) {
		pr_err("Ooops! Too many entries in the memory map!\n");
		return;
	}
	memmap_map[memmap_nr].addr = addr;
	memmap_map[memmap_nr].size = size;
	memmap_nr++;
}

static int __init setup_memmap(char *p)
{
	char *oldp;
	u64 start_at, mem_size;

	if (!p)
		return -EINVAL;

	if (!strncmp(p, "exactmap", 8)) {
		pr_err("\"memmap=exactmap\" not valid on tile\n");
		return 0;
	}

	oldp = p;
	mem_size = memparse(p, &p);
	if (p == oldp)
		return -EINVAL;

	if (*p == '@') {
		pr_err("\"memmap=nn@ss\" (force RAM) invalid on tile\n");
	} else if (*p == '#') {
		pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on tile\n");
	} else if (*p == '$') {
		start_at = memparse(p+1, &p);
		add_memmap_region(start_at, mem_size);
	} else {
		if (mem_size == 0)
			return -EINVAL;
		maxmem_pfn = (mem_size >> HPAGE_SHIFT) <<
			(HPAGE_SHIFT - PAGE_SHIFT);
	}
	return *p == '\0' ? 0 : -EINVAL;
}
early_param("memmap", setup_memmap);

static int __init setup_mem(char *str)
{
	return setup_maxmem(str);
}
early_param("mem", setup_mem);  /* compatibility with x86 */

static int __init setup_isolnodes(char *str)
{
	if (str == NULL || nodelist_parse(str, isolnodes) != 0)
		return -EINVAL;

	pr_info("Set isolnodes value to '%*pbl'\n",
		nodemask_pr_args(&isolnodes));
	return 0;
}
early_param("isolnodes", setup_isolnodes);

#if defined(CONFIG_PCI) && !defined(__tilegx__)
static int __init setup_pci_reserve(char* str)
{
	if (str == NULL || kstrtouint(str, 0, &pci_reserve_mb) != 0 ||
	    pci_reserve_mb > 3 * 1024)
		return -EINVAL;

	pr_info("Reserving %dMB for PCIE root complex mappings\n",
		pci_reserve_mb);
	return 0;
}
early_param("pci_reserve", setup_pci_reserve);
#endif

#ifndef __tilegx__
/*
 * vmalloc=size forces the vmalloc area to be exactly 'size' bytes.
 * This can be used to increase (or decrease) the vmalloc area.
 */
static int __init parse_vmalloc(char *arg)
{
	if (!arg)
		return -EINVAL;

	VMALLOC_RESERVE = (memparse(arg, &arg) + PGDIR_SIZE - 1) & PGDIR_MASK;

	/* See validate_va() for more on this test. */
	if ((long)_VMALLOC_START >= 0)
		early_panic("\"vmalloc=%#lx\" value too large: maximum %#lx\n",
			    VMALLOC_RESERVE, _VMALLOC_END - 0x80000000UL);

	return 0;
}
early_param("vmalloc", parse_vmalloc);
#endif

#ifdef CONFIG_HIGHMEM
/*
 * Determine for each controller where its lowmem is mapped and how much of
 * it is mapped there.  On controller zero, the first few megabytes are
 * already mapped in as code at MEM_SV_START, so in principle we could
 * start our data mappings higher up, but for now we don't bother, to avoid
 * additional confusion.
 *
 * One question is whether, on systems with more than 768 Mb and
 * controllers of different sizes, to map in a proportionate amount of
 * each one, or to try to map the same amount from each controller.
 * (E.g. if we have three controllers with 256MB, 1GB, and 256MB
 * respectively, do we map 256MB from each, or do we map 128 MB, 512
 * MB, and 128 MB respectively?)  For now we use a proportionate
 * solution like the latter.
 *
 * The VA/PA mapping demands that we align our decisions at 16 MB
 * boundaries so that we can rapidly convert VA to PA.
 */
static void *__init setup_pa_va_mapping(void)
{
	unsigned long curr_pages = 0;
	unsigned long vaddr = PAGE_OFFSET;
	nodemask_t highonlynodes = isolnodes;
	int i, j;

	memset(pbase_map, -1, sizeof(pbase_map));
	memset(vbase_map, -1, sizeof(vbase_map));

	/* Node zero cannot be isolated for LOWMEM purposes. */
	node_clear(0, highonlynodes);

	/* Count up the number of pages on non-highonlynodes controllers. */
	mappable_physpages = 0;
	for_each_online_node(i) {
		if (!node_isset(i, highonlynodes))
			mappable_physpages +=
				node_end_pfn[i] - node_start_pfn[i];
	}

	for_each_online_node(i) {
		unsigned long start = node_start_pfn[i];
		unsigned long end = node_end_pfn[i];
		unsigned long size = end - start;
		unsigned long vaddr_end;

		if (node_isset(i, highonlynodes)) {
			/* Mark this controller as having no lowmem. */
			node_lowmem_end_pfn[i] = start;
			continue;
		}

		curr_pages += size;
		if (mappable_physpages > MAXMEM_PFN) {
			vaddr_end = PAGE_OFFSET +
				(((u64)curr_pages * MAXMEM_PFN /
				  mappable_physpages)
				 << PAGE_SHIFT);
		} else {
			vaddr_end = PAGE_OFFSET + (curr_pages << PAGE_SHIFT);
		}
		for (j = 0; vaddr < vaddr_end; vaddr += HPAGE_SIZE, ++j) {
			unsigned long this_pfn =
				start + (j << HUGETLB_PAGE_ORDER);
			pbase_map[vaddr >> HPAGE_SHIFT] = this_pfn;
			if (vbase_map[__pfn_to_highbits(this_pfn)] ==
			    (void *)-1)
				vbase_map[__pfn_to_highbits(this_pfn)] =
					(void *)(vaddr & HPAGE_MASK);
		}
		node_lowmem_end_pfn[i] = start + (j << HUGETLB_PAGE_ORDER);
		BUG_ON(node_lowmem_end_pfn[i] > end);
	}

	/* Return highest address of any mapped memory. */
	return (void *)vaddr;
}
#endif /* CONFIG_HIGHMEM */

/*
 * Register our most important memory mappings with the debug stub.
 *
 * This is up to 4 mappings for lowmem, one mapping per memory
 * controller, plus one for our text segment.
 */
static void store_permanent_mappings(void)
{
	int i;

	for_each_online_node(i) {
		HV_PhysAddr pa = ((HV_PhysAddr)node_start_pfn[i]) << PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
		HV_PhysAddr high_mapped_pa = node_lowmem_end_pfn[i];
#else
		HV_PhysAddr high_mapped_pa = node_end_pfn[i];
#endif

		unsigned long pages = high_mapped_pa - node_start_pfn[i];
		HV_VirtAddr addr = (HV_VirtAddr) __va(pa);
		hv_store_mapping(addr, pages << PAGE_SHIFT, pa);
	}

	hv_store_mapping((HV_VirtAddr)_text,
			 (uint32_t)(_einittext - _text), 0);
}

/*
 * Use hv_inquire_physical() to populate node_{start,end}_pfn[]
 * and node_online_map, doing suitable sanity-checking.
 * Also set min_low_pfn, max_low_pfn, and max_pfn.
 */
static void __init setup_memory(void)
{
	int i, j;
	int highbits_seen[NR_PA_HIGHBIT_VALUES] = { 0 };
#ifdef CONFIG_HIGHMEM
	long highmem_pages;
#endif
#ifndef __tilegx__
	int cap;
#endif
#if defined(CONFIG_HIGHMEM) || defined(__tilegx__)
	long lowmem_pages;
#endif
	unsigned long physpages = 0;

	/* We are using a char to hold the cpu_2_node[] mapping */
	BUILD_BUG_ON(MAX_NUMNODES > 127);

	/* Discover the ranges of memory available to us */
	for (i = 0; ; ++i) {
		unsigned long start, size, end, highbits;
		HV_PhysAddrRange range = hv_inquire_physical(i);
		if (range.size == 0)
			break;
#ifdef CONFIG_FLATMEM
		if (i > 0) {
			pr_err("Can't use discontiguous PAs: %#llx..%#llx\n",
			       range.size, range.start + range.size);
			continue;
		}
#endif
#ifndef __tilegx__
		if ((unsigned long)range.start) {
			pr_err("Range not at 4GB multiple: %#llx..%#llx\n",
			       range.start, range.start + range.size);
			continue;
		}
#endif
		if ((range.start & (HPAGE_SIZE-1)) != 0 ||
		    (range.size & (HPAGE_SIZE-1)) != 0) {
			unsigned long long start_pa = range.start;
			unsigned long long orig_size = range.size;
			range.start = (start_pa + HPAGE_SIZE - 1) & HPAGE_MASK;
			range.size -= (range.start - start_pa);
			range.size &= HPAGE_MASK;
			pr_err("Range not hugepage-aligned: %#llx..%#llx: now %#llx-%#llx\n",
			       start_pa, start_pa + orig_size,
			       range.start, range.start + range.size);
		}
		highbits = __pa_to_highbits(range.start);
		if (highbits >= NR_PA_HIGHBIT_VALUES) {
			pr_err("PA high bits too high: %#llx..%#llx\n",
			       range.start, range.start + range.size);
			continue;
		}
		if (highbits_seen[highbits]) {
			pr_err("Range overlaps in high bits: %#llx..%#llx\n",
			       range.start, range.start + range.size);
			continue;
		}
		highbits_seen[highbits] = 1;
		if (PFN_DOWN(range.size) > maxnodemem_pfn[i]) {
			int max_size = maxnodemem_pfn[i];
			if (max_size > 0) {
				pr_err("Maxnodemem reduced node %d to %d pages\n",
				       i, max_size);
				range.size = PFN_PHYS(max_size);
			} else {
				pr_err("Maxnodemem disabled node %d\n", i);
				continue;
			}
		}
		if (physpages + PFN_DOWN(range.size) > maxmem_pfn) {
			int max_size = maxmem_pfn - physpages;
			if (max_size > 0) {
				pr_err("Maxmem reduced node %d to %d pages\n",
				       i, max_size);
				range.size = PFN_PHYS(max_size);
			} else {
				pr_err("Maxmem disabled node %d\n", i);
				continue;
			}
		}
		if (i >= MAX_NUMNODES) {
			pr_err("Too many PA nodes (#%d): %#llx...%#llx\n",
			       i, range.size, range.size + range.start);
			continue;
		}

		start = range.start >> PAGE_SHIFT;
		size = range.size >> PAGE_SHIFT;
		end = start + size;

#ifndef __tilegx__
		if (((HV_PhysAddr)end << PAGE_SHIFT) !=
		    (range.start + range.size)) {
			pr_err("PAs too high to represent: %#llx..%#llx\n",
			       range.start, range.start + range.size);
			continue;
		}
#endif
#if defined(CONFIG_PCI) && !defined(__tilegx__)
		/*
		 * Blocks that overlap the pci reserved region must
		 * have enough space to hold the maximum percpu data
		 * region at the top of the range.  If there isn't
		 * enough space above the reserved region, just
		 * truncate the node.
		 */
		if (start <= pci_reserve_start_pfn &&
		    end > pci_reserve_start_pfn) {
			unsigned int per_cpu_size =
				__per_cpu_end - __per_cpu_start;
			unsigned int percpu_pages =
				NR_CPUS * (PFN_UP(per_cpu_size) >> PAGE_SHIFT);
			if (end < pci_reserve_end_pfn + percpu_pages) {
				end = pci_reserve_start_pfn;
				pr_err("PCI mapping region reduced node %d to %ld pages\n",
				       i, end - start);
			}
		}
#endif

		for (j = __pfn_to_highbits(start);
		     j <= __pfn_to_highbits(end - 1); j++)
			highbits_to_node[j] = i;

		node_start_pfn[i] = start;
		node_end_pfn[i] = end;
		node_controller[i] = range.controller;
		physpages += size;
		max_pfn = end;

		/* Mark node as online */
		node_set(i, node_online_map);
		node_set(i, node_possible_map);
	}

#ifndef __tilegx__
	/*
	 * For 4KB pages, mem_map "struct page" data is 1% of the size
	 * of the physical memory, so can be quite big (640 MB for
	 * four 16G zones).  These structures must be mapped in
	 * lowmem, and since we currently cap out at about 768 MB,
	 * it's impractical to try to use this much address space.
	 * For now, arbitrarily cap the amount of physical memory
	 * we're willing to use at 8 million pages (32GB of 4KB pages).
	 */
	cap = 8 * 1024 * 1024;  /* 8 million pages */
	if (physpages > cap) {
		int num_nodes = num_online_nodes();
		int cap_each = cap / num_nodes;
		unsigned long dropped_pages = 0;
		for (i = 0; i < num_nodes; ++i) {
			int size = node_end_pfn[i] - node_start_pfn[i];
			if (size > cap_each) {
				dropped_pages += (size - cap_each);
				node_end_pfn[i] = node_start_pfn[i] + cap_each;
			}
		}
		physpages -= dropped_pages;
		pr_warn("Only using %ldMB memory - ignoring %ldMB\n",
			physpages >> (20 - PAGE_SHIFT),
			dropped_pages >> (20 - PAGE_SHIFT));
		pr_warn("Consider using a larger page size\n");
	}
#endif

	/* Heap starts just above the last loaded address. */
	min_low_pfn = PFN_UP((unsigned long)_end - PAGE_OFFSET);

#ifdef CONFIG_HIGHMEM
	/* Find where we map lowmem from each controller. */
	high_memory = setup_pa_va_mapping();

	/* Set max_low_pfn based on what node 0 can directly address. */
	max_low_pfn = node_lowmem_end_pfn[0];

	lowmem_pages = (mappable_physpages > MAXMEM_PFN) ?
		MAXMEM_PFN : mappable_physpages;
	highmem_pages = (long) (physpages - lowmem_pages);

	pr_notice("%ldMB HIGHMEM available\n",
		  pages_to_mb(highmem_pages > 0 ? highmem_pages : 0));
	pr_notice("%ldMB LOWMEM available\n", pages_to_mb(lowmem_pages));
#else
	/* Set max_low_pfn based on what node 0 can directly address. */
	max_low_pfn = node_end_pfn[0];

#ifndef __tilegx__
	if (node_end_pfn[0] > MAXMEM_PFN) {
		pr_warn("Only using %ldMB LOWMEM\n", MAXMEM >> 20);
		pr_warn("Use a HIGHMEM enabled kernel\n");
		max_low_pfn = MAXMEM_PFN;
		max_pfn = MAXMEM_PFN;
		node_end_pfn[0] = MAXMEM_PFN;
	} else {
		pr_notice("%ldMB memory available\n",
			  pages_to_mb(node_end_pfn[0]));
	}
	for (i = 1; i < MAX_NUMNODES; ++i) {
		node_start_pfn[i] = 0;
		node_end_pfn[i] = 0;
	}
	high_memory = __va(node_end_pfn[0]);
#else
	lowmem_pages = 0;
	for (i = 0; i < MAX_NUMNODES; ++i) {
		int pages = node_end_pfn[i] - node_start_pfn[i];
		lowmem_pages += pages;
		if (pages)
			high_memory = pfn_to_kaddr(node_end_pfn[i]);
	}
	pr_notice("%ldMB memory available\n", pages_to_mb(lowmem_pages));
#endif
#endif
}

/*
 * On 32-bit machines, we only put bootmem on the low controller,
 * since PAs > 4GB can't be used in bootmem.  In principle one could
 * imagine, e.g., multiple 1 GB controllers all of which could support
 * bootmem, but in practice using controllers this small isn't a
 * particularly interesting scenario, so we just keep it simple and
 * use only the first controller for bootmem on 32-bit machines.
 */
static inline int node_has_bootmem(int nid)
{
#ifdef CONFIG_64BIT
	return 1;
#else
	return nid == 0;
#endif
}

static inline unsigned long alloc_bootmem_pfn(int nid,
					      unsigned long size,
					      unsigned long goal)
{
	void *kva = __alloc_bootmem_node(NODE_DATA(nid), size,
					 PAGE_SIZE, goal);
	unsigned long pfn = kaddr_to_pfn(kva);
	BUG_ON(goal && PFN_PHYS(pfn) != goal);
	return pfn;
}

static void __init setup_bootmem_allocator_node(int i)
{
	unsigned long start, end, mapsize, mapstart;

	if (node_has_bootmem(i)) {
		NODE_DATA(i)->bdata = &bootmem_node_data[i];
	} else {
		/* Share controller zero's bdata for now. */
		NODE_DATA(i)->bdata = &bootmem_node_data[0];
		return;
	}

	/* Skip up to after the bss in node 0. */
	start = (i == 0) ? min_low_pfn : node_start_pfn[i];

	/* Only lowmem, if we're a HIGHMEM build. */
#ifdef CONFIG_HIGHMEM
	end = node_lowmem_end_pfn[i];
#else
	end = node_end_pfn[i];
#endif

	/* No memory here. */
	if (end == start)
		return;

	/* Figure out where the bootmem bitmap is located. */
	mapsize = bootmem_bootmap_pages(end - start);
	if (i == 0) {
		/* Use some space right before the heap on node 0. */
		mapstart = start;
		start += mapsize;
	} else {
		/* Allocate bitmap on node 0 to avoid page table issues. */
		mapstart = alloc_bootmem_pfn(0, PFN_PHYS(mapsize), 0);
	}

	/* Initialize a node. */
	init_bootmem_node(NODE_DATA(i), mapstart, start, end);

	/* Free all the space back into the allocator. */
	free_bootmem(PFN_PHYS(start), PFN_PHYS(end - start));

#if defined(CONFIG_PCI) && !defined(__tilegx__)
	/*
	 * Throw away any memory aliased by the PCI region.
	 */
	if (pci_reserve_start_pfn < end && pci_reserve_end_pfn > start) {
		start = max(pci_reserve_start_pfn, start);
		end = min(pci_reserve_end_pfn, end);
		reserve_bootmem(PFN_PHYS(start), PFN_PHYS(end - start),
				BOOTMEM_EXCLUSIVE);
	}
#endif
}

static void __init setup_bootmem_allocator(void)
{
	int i;
	for (i = 0; i < MAX_NUMNODES; ++i)
		setup_bootmem_allocator_node(i);

	/* Reserve any memory excluded by "memmap" arguments. */
	for (i = 0; i < memmap_nr; ++i) {
		struct memmap_entry *m = &memmap_map[i];
		reserve_bootmem(m->addr, m->size, BOOTMEM_DEFAULT);
	}

#ifdef CONFIG_BLK_DEV_INITRD
	if (initrd_start) {
		/* Make sure the initrd memory region is not modified. */
		if (reserve_bootmem(initrd_start, initrd_end - initrd_start,
				    BOOTMEM_EXCLUSIVE)) {
			pr_crit("The initrd memory region has been polluted. Disabling it.\n");
			initrd_start = 0;
			initrd_end = 0;
		} else {
			/*
			 * Translate initrd_start & initrd_end from PA to VA for
			 * future access.
			 */
			initrd_start += PAGE_OFFSET;
			initrd_end += PAGE_OFFSET;
		}
	}
#endif

#ifdef CONFIG_KEXEC
	if (crashk_res.start != crashk_res.end)
		reserve_bootmem(crashk_res.start, resource_size(&crashk_res),
				BOOTMEM_DEFAULT);
#endif
}

void *__init alloc_remap(int nid, unsigned long size)
{
	int pages = node_end_pfn[nid] - node_start_pfn[nid];
	void *map = pfn_to_kaddr(node_memmap_pfn[nid]);
	BUG_ON(size != pages * sizeof(struct page));
	memset(map, 0, size);
	return map;
}

static int __init percpu_size(void)
{
	int size = __per_cpu_end - __per_cpu_start;
	size += PERCPU_MODULE_RESERVE;
	size += PERCPU_DYNAMIC_EARLY_SIZE;
	if (size < PCPU_MIN_UNIT_SIZE)
		size = PCPU_MIN_UNIT_SIZE;
	size = roundup(size, PAGE_SIZE);

	/* In several places we assume the per-cpu data fits on a huge page. */
	BUG_ON(kdata_huge && size > HPAGE_SIZE);
	return size;
}

static void __init zone_sizes_init(void)
{
	unsigned long zones_size[MAX_NR_ZONES] = { 0 };
	int size = percpu_size();
	int num_cpus = smp_height * smp_width;
	const unsigned long dma_end = (1UL << (32 - PAGE_SHIFT));

	int i;

	for (i = 0; i < num_cpus; ++i)
		node_percpu[cpu_to_node(i)] += size;

	for_each_online_node(i) {
		unsigned long start = node_start_pfn[i];
		unsigned long end = node_end_pfn[i];
#ifdef CONFIG_HIGHMEM
		unsigned long lowmem_end = node_lowmem_end_pfn[i];
#else
		unsigned long lowmem_end = end;
#endif
		int memmap_size = (end - start) * sizeof(struct page);
		node_free_pfn[i] = start;

		/*
		 * Set aside pages for per-cpu data and the mem_map array.
		 *
		 * Since the per-cpu data requires special homecaching,
		 * if we are in kdata_huge mode, we put it at the end of
		 * the lowmem region.  If we're not in kdata_huge mode,
		 * we take the per-cpu pages from the bottom of the
		 * controller, since that avoids fragmenting a huge page
		 * that users might want.  We always take the memmap
		 * from the bottom of the controller, since with
		 * kdata_huge that lets it be under a huge TLB entry.
		 *
		 * If the user has requested isolnodes for a controller,
		 * though, there'll be no lowmem, so we just alloc_bootmem
		 * the memmap.  There will be no percpu memory either.
		 */
		if (i != 0 && node_isset(i, isolnodes)) {
			node_memmap_pfn[i] =
				alloc_bootmem_pfn(0, memmap_size, 0);
			BUG_ON(node_percpu[i] != 0);
		} else if (node_has_bootmem(start)) {
			unsigned long goal = 0;
			node_memmap_pfn[i] =
				alloc_bootmem_pfn(i, memmap_size, 0);
			if (kdata_huge)
				goal = PFN_PHYS(lowmem_end) - node_percpu[i];
			if (node_percpu[i])
				node_percpu_pfn[i] =
					alloc_bootmem_pfn(i, node_percpu[i],
							  goal);
		} else {
			/* In non-bootmem zones, just reserve some pages. */
			node_memmap_pfn[i] = node_free_pfn[i];
			node_free_pfn[i] += PFN_UP(memmap_size);
			if (!kdata_huge) {
				node_percpu_pfn[i] = node_free_pfn[i];
				node_free_pfn[i] += PFN_UP(node_percpu[i]);
			} else {
				node_percpu_pfn[i] =
					lowmem_end - PFN_UP(node_percpu[i]);
			}
		}

#ifdef CONFIG_HIGHMEM
		if (start > lowmem_end) {
			zones_size[ZONE_NORMAL] = 0;
			zones_size[ZONE_HIGHMEM] = end - start;
		} else {
			zones_size[ZONE_NORMAL] = lowmem_end - start;
			zones_size[ZONE_HIGHMEM] = end - lowmem_end;
		}
#else
		zones_size[ZONE_NORMAL] = end - start;
#endif

		if (start < dma_end) {
			zones_size[ZONE_DMA] = min(zones_size[ZONE_NORMAL],
						   dma_end - start);
			zones_size[ZONE_NORMAL] -= zones_size[ZONE_DMA];
		} else {
			zones_size[ZONE_DMA] = 0;
		}

		/* Take zone metadata from controller 0 if we're isolnode. */
		if (node_isset(i, isolnodes))
			NODE_DATA(i)->bdata = &bootmem_node_data[0];

		free_area_init_node(i, zones_size, start, NULL);
		printk(KERN_DEBUG "  Normal zone: %ld per-cpu pages\n",
		       PFN_UP(node_percpu[i]));

		/* Track the type of memory on each node */
		if (zones_size[ZONE_NORMAL] || zones_size[ZONE_DMA])
			node_set_state(i, N_NORMAL_MEMORY);
#ifdef CONFIG_HIGHMEM
		if (end != start)
			node_set_state(i, N_HIGH_MEMORY);
#endif

		node_set_online(i);
	}
}

#ifdef CONFIG_NUMA

/* which logical CPUs are on which nodes */
struct cpumask node_2_cpu_mask[MAX_NUMNODES] __ro_after_init;
EXPORT_SYMBOL(node_2_cpu_mask);

/* which node each logical CPU is on */
char cpu_2_node[NR_CPUS] __ro_after_init __attribute__((aligned(L2_CACHE_BYTES)));
EXPORT_SYMBOL(cpu_2_node);

/* Return cpu_to_node() except for cpus not yet assigned, which return -1 */
static int __init cpu_to_bound_node(int cpu, struct cpumask* unbound_cpus)
{
	if (!cpu_possible(cpu) || cpumask_test_cpu(cpu, unbound_cpus))
		return -1;
	else
		return cpu_to_node(cpu);
}

/* Return number of immediately-adjacent tiles sharing the same NUMA node. */
static int __init node_neighbors(int node, int cpu,
				 struct cpumask *unbound_cpus)
{
	int neighbors = 0;
	int w = smp_width;
	int h = smp_height;
	int x = cpu % w;
	int y = cpu / w;
	if (x > 0 && cpu_to_bound_node(cpu-1, unbound_cpus) == node)
		++neighbors;
	if (x < w-1 && cpu_to_bound_node(cpu+1, unbound_cpus) == node)
		++neighbors;
	if (y > 0 && cpu_to_bound_node(cpu-w, unbound_cpus) == node)
		++neighbors;
	if (y < h-1 && cpu_to_bound_node(cpu+w, unbound_cpus) == node)
		++neighbors;
	return neighbors;
}

static void __init setup_numa_mapping(void)
{
	u8 distance[MAX_NUMNODES][NR_CPUS];
	HV_Coord coord;
	int cpu, node, cpus, i, x, y;
	int num_nodes = num_online_nodes();
	struct cpumask unbound_cpus;
	nodemask_t default_nodes;

	cpumask_clear(&unbound_cpus);

	/* Get set of nodes we will use for defaults */
	nodes_andnot(default_nodes, node_online_map, isolnodes);
	if (nodes_empty(default_nodes)) {
		BUG_ON(!node_isset(0, node_online_map));
		pr_err("Forcing NUMA node zero available as a default node\n");
		node_set(0, default_nodes);
	}

	/* Populate the distance[] array */
	memset(distance, -1, sizeof(distance));
	cpu = 0;
	for (coord.y = 0; coord.y < smp_height; ++coord.y) {
		for (coord.x = 0; coord.x < smp_width;
		     ++coord.x, ++cpu) {
			BUG_ON(cpu >= nr_cpu_ids);
			if (!cpu_possible(cpu)) {
				cpu_2_node[cpu] = -1;
				continue;
			}
			for_each_node_mask(node, default_nodes) {
				HV_MemoryControllerInfo info =
					hv_inquire_memory_controller(
						coord, node_controller[node]);
				distance[node][cpu] =
					ABS(info.coord.x) + ABS(info.coord.y);
			}
			cpumask_set_cpu(cpu, &unbound_cpus);
		}
	}
	cpus = cpu;

	/*
	 * Round-robin through the NUMA nodes until all the cpus are
	 * assigned.  We could be more clever here (e.g. create four
	 * sorted linked lists on the same set of cpu nodes, and pull
	 * off them in round-robin sequence, removing from all four
	 * lists each time) but given the relatively small numbers
	 * involved, O(n^2) seem OK for a one-time cost.
	 */
	node = first_node(default_nodes);
	while (!cpumask_empty(&unbound_cpus)) {
		int best_cpu = -1;
		int best_distance = INT_MAX;
		for (cpu = 0; cpu < cpus; ++cpu) {
			if (cpumask_test_cpu(cpu, &unbound_cpus)) {
				/*
				 * Compute metric, which is how much
				 * closer the cpu is to this memory
				 * controller than the others, shifted
				 * up, and then the number of
				 * neighbors already in the node as an
				 * epsilon adjustment to try to keep
				 * the nodes compact.
				 */
				int d = distance[node][cpu] * num_nodes;
				for_each_node_mask(i, default_nodes) {
					if (i != node)
						d -= distance[i][cpu];
				}
				d *= 8;  /* allow space for epsilon */
				d -= node_neighbors(node, cpu, &unbound_cpus);
				if (d < best_distance) {
					best_cpu = cpu;
					best_distance = d;
				}
			}
		}
		BUG_ON(best_cpu < 0);
		cpumask_set_cpu(best_cpu, &node_2_cpu_mask[node]);
		cpu_2_node[best_cpu] = node;
		cpumask_clear_cpu(best_cpu, &unbound_cpus);
		node = next_node_in(node, default_nodes);
	}

	/* Print out node assignments and set defaults for disabled cpus */
	cpu = 0;
	for (y = 0; y < smp_height; ++y) {
		printk(KERN_DEBUG "NUMA cpu-to-node row %d:", y);
		for (x = 0; x < smp_width; ++x, ++cpu) {
			if (cpu_to_node(cpu) < 0) {
				pr_cont(" -");
				cpu_2_node[cpu] = first_node(default_nodes);
			} else {
				pr_cont(" %d", cpu_to_node(cpu));
			}
		}
		pr_cont("\n");
	}
}

static struct cpu cpu_devices[NR_CPUS];

static int __init topology_init(void)
{
	int i;

	for_each_online_node(i)
		register_one_node(i);

	for (i = 0; i < smp_height * smp_width; ++i)
		register_cpu(&cpu_devices[i], i);

	return 0;
}

subsys_initcall(topology_init);

#else /* !CONFIG_NUMA */

#define setup_numa_mapping() do { } while (0)

#endif /* CONFIG_NUMA */

/*
 * Initialize hugepage support on this cpu.  We do this on all cores
 * early in boot: before argument parsing for the boot cpu, and after
 * argument parsing but before the init functions run on the secondaries.
 * So the values we set up here in the hypervisor may be overridden on
 * the boot cpu as arguments are parsed.
 */
static void init_super_pages(void)
{
#ifdef CONFIG_HUGETLB_SUPER_PAGES
	int i;
	for (i = 0; i < HUGE_SHIFT_ENTRIES; ++i)
		hv_set_pte_super_shift(i, huge_shift[i]);
#endif
}

/**
 * setup_cpu() - Do all necessary per-cpu, tile-specific initialization.
 * @boot: Is this the boot cpu?
 *
 * Called from setup_arch() on the boot cpu, or online_secondary().
 */
void setup_cpu(int boot)
{
	/* The boot cpu sets up its permanent mappings much earlier. */
	if (!boot)
		store_permanent_mappings();

	/* Allow asynchronous TLB interrupts. */
#if CHIP_HAS_TILE_DMA()
	arch_local_irq_unmask(INT_DMATLB_MISS);
	arch_local_irq_unmask(INT_DMATLB_ACCESS);
#endif
#ifdef __tilegx__
	arch_local_irq_unmask(INT_SINGLE_STEP_K);
#endif

	/*
	 * Allow user access to many generic SPRs, like the cycle
	 * counter, PASS/FAIL/DONE, INTERRUPT_CRITICAL_SECTION, etc.
	 */
	__insn_mtspr(SPR_MPL_WORLD_ACCESS_SET_0, 1);

#if CHIP_HAS_SN()
	/* Static network is not restricted. */
	__insn_mtspr(SPR_MPL_SN_ACCESS_SET_0, 1);
#endif

	/*
	 * Set the MPL for interrupt control 0 & 1 to the corresponding
	 * values.  This includes access to the SYSTEM_SAVE and EX_CONTEXT
	 * SPRs, as well as the interrupt mask.
	 */
	__insn_mtspr(SPR_MPL_INTCTRL_0_SET_0, 1);
	__insn_mtspr(SPR_MPL_INTCTRL_1_SET_1, 1);

	/* Initialize IRQ support for this cpu. */
	setup_irq_regs();

#ifdef CONFIG_HARDWALL
	/* Reset the network state on this cpu. */
	reset_network_state();
#endif

	init_super_pages();
}

#ifdef CONFIG_BLK_DEV_INITRD

static int __initdata set_initramfs_file;
static char __initdata initramfs_file[128] = "initramfs";

static int __init setup_initramfs_file(char *str)
{
	if (str == NULL)
		return -EINVAL;
	strncpy(initramfs_file, str, sizeof(initramfs_file) - 1);
	set_initramfs_file = 1;

	return 0;
}
early_param("initramfs_file", setup_initramfs_file);

/*
 * We look for a file called "initramfs" in the hvfs.  If there is one, we
 * allocate some memory for it and it will be unpacked to the initramfs.
 * If it's compressed, the initd code will uncompress it first.
 */
static void __init load_hv_initrd(void)
{
	HV_FS_StatInfo stat;
	int fd, rc;
	void *initrd;

	/* If initrd has already been set, skip initramfs file in hvfs. */
	if (initrd_start)
		return;

	fd = hv_fs_findfile((HV_VirtAddr) initramfs_file);
	if (fd == HV_ENOENT) {
		if (set_initramfs_file) {
			pr_warn("No such hvfs initramfs file '%s'\n",
				initramfs_file);
			return;
		} else {
			/* Try old backwards-compatible name. */
			fd = hv_fs_findfile((HV_VirtAddr)"initramfs.cpio.gz");
			if (fd == HV_ENOENT)
				return;
		}
	}
	BUG_ON(fd < 0);
	stat = hv_fs_fstat(fd);
	BUG_ON(stat.size < 0);
	if (stat.flags & HV_FS_ISDIR) {
		pr_warn("Ignoring hvfs file '%s': it's a directory\n",
			initramfs_file);
		return;
	}
	initrd = alloc_bootmem_pages(stat.size);
	rc = hv_fs_pread(fd, (HV_VirtAddr) initrd, stat.size, 0);
	if (rc != stat.size) {
		pr_err("Error reading %d bytes from hvfs file '%s': %d\n",
		       stat.size, initramfs_file, rc);
		free_initrd_mem((unsigned long) initrd, stat.size);
		return;
	}
	initrd_start = (unsigned long) initrd;
	initrd_end = initrd_start + stat.size;
}

void __init free_initrd_mem(unsigned long begin, unsigned long end)
{
	free_bootmem_late(__pa(begin), end - begin);
}

static int __init setup_initrd(char *str)
{
	char *endp;
	unsigned long initrd_size;

	initrd_size = str ? simple_strtoul(str, &endp, 0) : 0;
	if (initrd_size == 0 || *endp != '@')
		return -EINVAL;

	initrd_start = simple_strtoul(endp+1, &endp, 0);
	if (initrd_start == 0)
		return -EINVAL;

	initrd_end = initrd_start + initrd_size;

	return 0;
}
early_param("initrd", setup_initrd);

#else
static inline void load_hv_initrd(void) {}
#endif /* CONFIG_BLK_DEV_INITRD */

static void __init validate_hv(void)
{
	/*
	 * It may already be too late, but let's check our built-in
	 * configuration against what the hypervisor is providing.
	 */
	unsigned long glue_size = hv_sysconf(HV_SYSCONF_GLUE_SIZE);
	int hv_page_size = hv_sysconf(HV_SYSCONF_PAGE_SIZE_SMALL);
	int hv_hpage_size = hv_sysconf(HV_SYSCONF_PAGE_SIZE_LARGE);
	HV_ASIDRange asid_range;

#ifndef CONFIG_SMP
	HV_Topology topology = hv_inquire_topology();
	BUG_ON(topology.coord.x != 0 || topology.coord.y != 0);
	if (topology.width != 1 || topology.height != 1) {
		pr_warn("Warning: booting UP kernel on %dx%d grid; will ignore all but first tile\n",
			topology.width, topology.height);
	}
#endif

	if (PAGE_OFFSET + HV_GLUE_START_CPA + glue_size > (unsigned long)_text)
		early_panic("Hypervisor glue size %ld is too big!\n",
			    glue_size);
	if (hv_page_size != PAGE_SIZE)
		early_panic("Hypervisor page size %#x != our %#lx\n",
			    hv_page_size, PAGE_SIZE);
	if (hv_hpage_size != HPAGE_SIZE)
		early_panic("Hypervisor huge page size %#x != our %#lx\n",
			    hv_hpage_size, HPAGE_SIZE);

#ifdef CONFIG_SMP
	/*
	 * Some hypervisor APIs take a pointer to a bitmap array
	 * whose size is at least the number of cpus on the chip.
	 * We use a struct cpumask for this, so it must be big enough.
	 */
	if ((smp_height * smp_width) > nr_cpu_ids)
		early_panic("Hypervisor %d x %d grid too big for Linux NR_CPUS %d\n",
			    smp_height, smp_width, nr_cpu_ids);
#endif

	/*
	 * Check that we're using allowed ASIDs, and initialize the
	 * various asid variables to their appropriate initial states.
	 */
	asid_range = hv_inquire_asid(0);
	min_asid = asid_range.start;
	__this_cpu_write(current_asid, min_asid);
	max_asid = asid_range.start + asid_range.size - 1;

	if (hv_confstr(HV_CONFSTR_CHIP_MODEL, (HV_VirtAddr)chip_model,
		       sizeof(chip_model)) < 0) {
		pr_err("Warning: HV_CONFSTR_CHIP_MODEL not available\n");
		strlcpy(chip_model, "unknown", sizeof(chip_model));
	}
}

static void __init validate_va(void)
{
#ifndef __tilegx__   /* FIXME: GX: probably some validation relevant here */
	/*
	 * Similarly, make sure we're only using allowed VAs.
	 * We assume we can contiguously use MEM_USER_INTRPT .. MEM_HV_START,
	 * and 0 .. KERNEL_HIGH_VADDR.
	 * In addition, make sure we CAN'T use the end of memory, since
	 * we use the last chunk of each pgd for the pgd_list.
	 */
	int i, user_kernel_ok = 0;
	unsigned long max_va = 0;
	unsigned long list_va =
		((PGD_LIST_OFFSET / sizeof(pgd_t)) << PGDIR_SHIFT);

	for (i = 0; ; ++i) {
		HV_VirtAddrRange range = hv_inquire_virtual(i);
		if (range.size == 0)
			break;
		if (range.start <= MEM_USER_INTRPT &&
		    range.start + range.size >= MEM_HV_START)
			user_kernel_ok = 1;
		if (range.start == 0)
			max_va = range.size;
		BUG_ON(range.start + range.size > list_va);
	}
	if (!user_kernel_ok)
		early_panic("Hypervisor not configured for user/kernel VAs\n");
	if (max_va == 0)
		early_panic("Hypervisor not configured for low VAs\n");
	if (max_va < KERNEL_HIGH_VADDR)
		early_panic("Hypervisor max VA %#lx smaller than %#lx\n",
			    max_va, KERNEL_HIGH_VADDR);

	/* Kernel PCs must have their high bit set; see intvec.S. */
	if ((long)VMALLOC_START >= 0)
		early_panic("Linux VMALLOC region below the 2GB line (%#lx)!\n"
			    "Reconfigure the kernel with smaller VMALLOC_RESERVE\n",
			    VMALLOC_START);
#endif
}

/*
 * cpu_lotar_map lists all the cpus that are valid for the supervisor
 * to cache data on at a page level, i.e. what cpus can be placed in
 * the LOTAR field of a PTE.  It is equivalent to the set of possible
 * cpus plus any other cpus that are willing to share their cache.
 * It is set by hv_inquire_tiles(HV_INQ_TILES_LOTAR).
 */
struct cpumask __ro_after_init cpu_lotar_map;
EXPORT_SYMBOL(cpu_lotar_map);

/*
 * hash_for_home_map lists all the tiles that hash-for-home data
 * will be cached on.  Note that this may includes tiles that are not
 * valid for this supervisor to use otherwise (e.g. if a hypervisor
 * device is being shared between multiple supervisors).
 * It is set by hv_inquire_tiles(HV_INQ_TILES_HFH_CACHE).
 */
struct cpumask hash_for_home_map;
EXPORT_SYMBOL(hash_for_home_map);

/*
 * cpu_cacheable_map lists all the cpus whose caches the hypervisor can
 * flush on our behalf.  It is set to cpu_possible_mask OR'ed with
 * hash_for_home_map, and it is what should be passed to
 * hv_flush_remote() to flush all caches.  Note that if there are
 * dedicated hypervisor driver tiles that have authorized use of their
 * cache, those tiles will only appear in cpu_lotar_map, NOT in
 * cpu_cacheable_map, as they are a special case.
 */
struct cpumask __ro_after_init cpu_cacheable_map;
EXPORT_SYMBOL(cpu_cacheable_map);

static __initdata struct cpumask disabled_map;

static int __init disabled_cpus(char *str)
{
	int boot_cpu = smp_processor_id();

	if (str == NULL || cpulist_parse_crop(str, &disabled_map) != 0)
		return -EINVAL;
	if (cpumask_test_cpu(boot_cpu, &disabled_map)) {
		pr_err("disabled_cpus: can't disable boot cpu %d\n", boot_cpu);
		cpumask_clear_cpu(boot_cpu, &disabled_map);
	}
	return 0;
}

early_param("disabled_cpus", disabled_cpus);

void __init print_disabled_cpus(void)
{
	if (!cpumask_empty(&disabled_map))
		pr_info("CPUs not available for Linux: %*pbl\n",
			cpumask_pr_args(&disabled_map));
}

static void __init setup_cpu_maps(void)
{
	struct cpumask hv_disabled_map, cpu_possible_init;
	int boot_cpu = smp_processor_id();
	int cpus, i, rc;

	/* Learn which cpus are allowed by the hypervisor. */
	rc = hv_inquire_tiles(HV_INQ_TILES_AVAIL,
			      (HV_VirtAddr) cpumask_bits(&cpu_possible_init),
			      sizeof(cpu_cacheable_map));
	if (rc < 0)
		early_panic("hv_inquire_tiles(AVAIL) failed: rc %d\n", rc);
	if (!cpumask_test_cpu(boot_cpu, &cpu_possible_init))
		early_panic("Boot CPU %d disabled by hypervisor!\n", boot_cpu);

	/* Compute the cpus disabled by the hvconfig file. */
	cpumask_complement(&hv_disabled_map, &cpu_possible_init);

	/* Include them with the cpus disabled by "disabled_cpus". */
	cpumask_or(&disabled_map, &disabled_map, &hv_disabled_map);

	/*
	 * Disable every cpu after "setup_max_cpus".  But don't mark
	 * as disabled the cpus that are outside of our initial rectangle,
	 * since that turns out to be confusing.
	 */
	cpus = 1;                          /* this cpu */
	cpumask_set_cpu(boot_cpu, &disabled_map);   /* ignore this cpu */
	for (i = 0; cpus < setup_max_cpus; ++i)
		if (!cpumask_test_cpu(i, &disabled_map))
			++cpus;
	for (; i < smp_height * smp_width; ++i)
		cpumask_set_cpu(i, &disabled_map);
	cpumask_clear_cpu(boot_cpu, &disabled_map); /* reset this cpu */
	for (i = smp_height * smp_width; i < NR_CPUS; ++i)
		cpumask_clear_cpu(i, &disabled_map);

	/*
	 * Setup cpu_possible map as every cpu allocated to us, minus
	 * the results of any "disabled_cpus" settings.
	 */
	cpumask_andnot(&cpu_possible_init, &cpu_possible_init, &disabled_map);
	init_cpu_possible(&cpu_possible_init);

	/* Learn which cpus are valid for LOTAR caching. */
	rc = hv_inquire_tiles(HV_INQ_TILES_LOTAR,
			      (HV_VirtAddr) cpumask_bits(&cpu_lotar_map),
			      sizeof(cpu_lotar_map));
	if (rc < 0) {
		pr_err("warning: no HV_INQ_TILES_LOTAR; using AVAIL\n");
		cpu_lotar_map = *cpu_possible_mask;
	}

	/* Retrieve set of CPUs used for hash-for-home caching */
	rc = hv_inquire_tiles(HV_INQ_TILES_HFH_CACHE,
			      (HV_VirtAddr) hash_for_home_map.bits,
			      sizeof(hash_for_home_map));
	if (rc < 0)
		early_panic("hv_inquire_tiles(HFH_CACHE) failed: rc %d\n", rc);
	cpumask_or(&cpu_cacheable_map, cpu_possible_mask, &hash_for_home_map);
}


static int __init dataplane(char *str)
{
	pr_warn("WARNING: dataplane support disabled in this kernel\n");
	return 0;
}

early_param("dataplane", dataplane);

#ifdef CONFIG_NO_HZ_FULL
/* Warn if hypervisor shared cpus are marked as nohz_full. */
static int __init check_nohz_full_cpus(void)
{
	struct cpumask shared;
	int cpu;

	if (hv_inquire_tiles(HV_INQ_TILES_SHARED,
			     (HV_VirtAddr) shared.bits, sizeof(shared)) < 0) {
		pr_warn("WARNING: No support for inquiring hv shared tiles\n");
		return 0;
	}
	for_each_cpu(cpu, &shared) {
		if (tick_nohz_full_cpu(cpu))
			pr_warn("WARNING: nohz_full cpu %d receives hypervisor interrupts!\n",
			       cpu);
	}
	return 0;
}
arch_initcall(check_nohz_full_cpus);
#endif

#ifdef CONFIG_CMDLINE_BOOL
static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
#endif

void __init setup_arch(char **cmdline_p)
{
	int len;

#if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
	len = hv_get_command_line((HV_VirtAddr) boot_command_line,
				  COMMAND_LINE_SIZE);
	if (boot_command_line[0])
		pr_warn("WARNING: ignoring dynamic command line \"%s\"\n",
			boot_command_line);
	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
#else
	char *hv_cmdline;
#if defined(CONFIG_CMDLINE_BOOL)
	if (builtin_cmdline[0]) {
		int builtin_len = strlcpy(boot_command_line, builtin_cmdline,
					  COMMAND_LINE_SIZE);
		if (builtin_len < COMMAND_LINE_SIZE-1)
			boot_command_line[builtin_len++] = ' ';
		hv_cmdline = &boot_command_line[builtin_len];
		len = COMMAND_LINE_SIZE - builtin_len;
	} else
#endif
	{
		hv_cmdline = boot_command_line;
		len = COMMAND_LINE_SIZE;
	}
	len = hv_get_command_line((HV_VirtAddr) hv_cmdline, len);
	if (len < 0 || len > COMMAND_LINE_SIZE)
		early_panic("hv_get_command_line failed: %d\n", len);
#endif

	*cmdline_p = boot_command_line;

	/* Set disabled_map and setup_max_cpus very early */
	parse_early_param();

	/* Make sure the kernel is compatible with the hypervisor. */
	validate_hv();
	validate_va();

	setup_cpu_maps();


#if defined(CONFIG_PCI) && !defined(__tilegx__)
	/*
	 * Initialize the PCI structures.  This is done before memory
	 * setup so that we know whether or not a pci_reserve region
	 * is necessary.
	 */
	if (tile_pci_init() == 0)
		pci_reserve_mb = 0;

	/* PCI systems reserve a region just below 4GB for mapping iomem. */
	pci_reserve_end_pfn  = (1 << (32 - PAGE_SHIFT));
	pci_reserve_start_pfn = pci_reserve_end_pfn -
		(pci_reserve_mb << (20 - PAGE_SHIFT));
#endif

	init_mm.start_code = (unsigned long) _text;
	init_mm.end_code = (unsigned long) _etext;
	init_mm.end_data = (unsigned long) _edata;
	init_mm.brk = (unsigned long) _end;

	setup_memory();
	store_permanent_mappings();
	setup_bootmem_allocator();

	/*
	 * NOTE: before this point _nobody_ is allowed to allocate
	 * any memory using the bootmem allocator.
	 */

#ifdef CONFIG_SWIOTLB
	swiotlb_init(0);
#endif

	paging_init();
	setup_numa_mapping();
	zone_sizes_init();
	set_page_homes();
	setup_cpu(1);
	setup_clock();
	load_hv_initrd();
}


/*
 * Set up per-cpu memory.
 */

unsigned long __per_cpu_offset[NR_CPUS] __ro_after_init;
EXPORT_SYMBOL(__per_cpu_offset);

static size_t __initdata pfn_offset[MAX_NUMNODES] = { 0 };
static unsigned long __initdata percpu_pfn[NR_CPUS] = { 0 };

/*
 * As the percpu code allocates pages, we return the pages from the
 * end of the node for the specified cpu.
 */
static void *__init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
{
	int nid = cpu_to_node(cpu);
	unsigned long pfn = node_percpu_pfn[nid] + pfn_offset[nid];

	BUG_ON(size % PAGE_SIZE != 0);
	pfn_offset[nid] += size / PAGE_SIZE;
	BUG_ON(node_percpu[nid] < size);
	node_percpu[nid] -= size;
	if (percpu_pfn[cpu] == 0)
		percpu_pfn[cpu] = pfn;
	return pfn_to_kaddr(pfn);
}

/*
 * Pages reserved for percpu memory are not freeable, and in any case we are
 * on a short path to panic() in setup_per_cpu_area() at this point anyway.
 */
static void __init pcpu_fc_free(void *ptr, size_t size)
{
}

/*
 * Set up vmalloc page tables using bootmem for the percpu code.
 */
static void __init pcpu_fc_populate_pte(unsigned long addr)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	BUG_ON(pgd_addr_invalid(addr));
	if (addr < VMALLOC_START || addr >= VMALLOC_END)
		panic("PCPU addr %#lx outside vmalloc range %#lx..%#lx; try increasing CONFIG_VMALLOC_RESERVE\n",
		      addr, VMALLOC_START, VMALLOC_END);

	pgd = swapper_pg_dir + pgd_index(addr);
	pud = pud_offset(pgd, addr);
	BUG_ON(!pud_present(*pud));
	pmd = pmd_offset(pud, addr);
	if (pmd_present(*pmd)) {
		BUG_ON(pmd_huge_page(*pmd));
	} else {
		pte = __alloc_bootmem(L2_KERNEL_PGTABLE_SIZE,
				      HV_PAGE_TABLE_ALIGN, 0);
		pmd_populate_kernel(&init_mm, pmd, pte);
	}
}

void __init setup_per_cpu_areas(void)
{
	struct page *pg;
	unsigned long delta, pfn, lowmem_va;
	unsigned long size = percpu_size();
	char *ptr;
	int rc, cpu, i;

	rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE, pcpu_fc_alloc,
				   pcpu_fc_free, pcpu_fc_populate_pte);
	if (rc < 0)
		panic("Cannot initialize percpu area (err=%d)", rc);

	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
	for_each_possible_cpu(cpu) {
		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];

		/* finv the copy out of cache so we can change homecache */
		ptr = pcpu_base_addr + pcpu_unit_offsets[cpu];
		__finv_buffer(ptr, size);
		pfn = percpu_pfn[cpu];

		/* Rewrite the page tables to cache on that cpu */
		pg = pfn_to_page(pfn);
		for (i = 0; i < size; i += PAGE_SIZE, ++pfn, ++pg) {

			/* Update the vmalloc mapping and page home. */
			unsigned long addr = (unsigned long)ptr + i;
			pte_t *ptep = virt_to_kpte(addr);
			pte_t pte = *ptep;
			BUG_ON(pfn != pte_pfn(pte));
			pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_TILE_L3);
			pte = set_remote_cache_cpu(pte, cpu);
			set_pte_at(&init_mm, addr, ptep, pte);

			/* Update the lowmem mapping for consistency. */
			lowmem_va = (unsigned long)pfn_to_kaddr(pfn);
			ptep = virt_to_kpte(lowmem_va);
			if (pte_huge(*ptep)) {
				printk(KERN_DEBUG "early shatter of huge page at %#lx\n",
				       lowmem_va);
				shatter_pmd((pmd_t *)ptep);
				ptep = virt_to_kpte(lowmem_va);
				BUG_ON(pte_huge(*ptep));
			}
			BUG_ON(pfn != pte_pfn(*ptep));
			set_pte_at(&init_mm, lowmem_va, ptep, pte);
		}
	}

	/* Set our thread pointer appropriately. */
	set_my_cpu_offset(__per_cpu_offset[smp_processor_id()]);

	/* Make sure the finv's have completed. */
	mb_incoherent();

	/* Flush the TLB so we reference it properly from here on out. */
	local_flush_tlb_all();
}

static struct resource data_resource = {
	.name	= "Kernel data",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
};

static struct resource code_resource = {
	.name	= "Kernel code",
	.start	= 0,
	.end	= 0,
	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
};

/*
 * On Pro, we reserve all resources above 4GB so that PCI won't try to put
 * mappings above 4GB.
 */
#if defined(CONFIG_PCI) && !defined(__tilegx__)
static struct resource* __init
insert_non_bus_resource(void)
{
	struct resource *res =
		kzalloc(sizeof(struct resource), GFP_ATOMIC);
	if (!res)
		return NULL;
	res->name = "Non-Bus Physical Address Space";
	res->start = (1ULL << 32);
	res->end = -1LL;
	res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
	if (insert_resource(&iomem_resource, res)) {
		kfree(res);
		return NULL;
	}
	return res;
}
#endif

static struct resource* __init
insert_ram_resource(u64 start_pfn, u64 end_pfn, bool reserved)
{
	struct resource *res =
		kzalloc(sizeof(struct resource), GFP_ATOMIC);
	if (!res)
		return NULL;
	res->start = start_pfn << PAGE_SHIFT;
	res->end = (end_pfn << PAGE_SHIFT) - 1;
	res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
	if (reserved) {
		res->name = "Reserved";
	} else {
		res->name = "System RAM";
		res->flags |= IORESOURCE_SYSRAM;
	}
	if (insert_resource(&iomem_resource, res)) {
		kfree(res);
		return NULL;
	}
	return res;
}

/*
 * Request address space for all standard resources
 *
 * If the system includes PCI root complex drivers, we need to create
 * a window just below 4GB where PCI BARs can be mapped.
 */
static int __init request_standard_resources(void)
{
	int i;
	enum { CODE_DELTA = MEM_SV_START - PAGE_OFFSET };

#if defined(CONFIG_PCI) && !defined(__tilegx__)
	insert_non_bus_resource();
#endif

	for_each_online_node(i) {
		u64 start_pfn = node_start_pfn[i];
		u64 end_pfn = node_end_pfn[i];

#if defined(CONFIG_PCI) && !defined(__tilegx__)
		if (start_pfn <= pci_reserve_start_pfn &&
		    end_pfn > pci_reserve_start_pfn) {
			if (end_pfn > pci_reserve_end_pfn)
				insert_ram_resource(pci_reserve_end_pfn,
						    end_pfn, 0);
			end_pfn = pci_reserve_start_pfn;
		}
#endif
		insert_ram_resource(start_pfn, end_pfn, 0);
	}

	code_resource.start = __pa(_text - CODE_DELTA);
	code_resource.end = __pa(_etext - CODE_DELTA)-1;
	data_resource.start = __pa(_sdata);
	data_resource.end = __pa(_end)-1;

	insert_resource(&iomem_resource, &code_resource);
	insert_resource(&iomem_resource, &data_resource);

	/* Mark any "memmap" regions busy for the resource manager. */
	for (i = 0; i < memmap_nr; ++i) {
		struct memmap_entry *m = &memmap_map[i];
		insert_ram_resource(PFN_DOWN(m->addr),
				    PFN_UP(m->addr + m->size - 1), 1);
	}

#ifdef CONFIG_KEXEC
	insert_resource(&iomem_resource, &crashk_res);
#endif

	return 0;
}

subsys_initcall(request_standard_resources);