/*
   * Ported from IRIX to Linux by Kanoj Sarcar, 06/08/00.
   * Copyright 2000 - 2001 Silicon Graphics, Inc.
   * Copyright 2000 - 2001 Kanoj Sarcar (kanoj@sgi.com)
   */

  #include <linux/init.h>

  #include <linux/mm.h>

  #include <linux/mmzone.h>
  #include <linux/kernel.h>
  #include <linux/nodemask.h>
  #include <linux/string.h>
  
  #include <asm/page.h>
  #include <asm/sections.h>

  #include <asm/sn/types.h>
  #include <asm/sn/arch.h>
  #include <asm/sn/gda.h>
  #include <asm/sn/hub.h>
  #include <asm/sn/mapped_kernel.h>
  #include <asm/sn/sn_private.h>
  
  static cpumask_t ktext_repmask;
  
  /*
   * XXX - This needs to be much smarter about where it puts copies of the
   * kernel.  For example, we should never put a copy on a headless node,
   * and we should respect the topology of the machine.
   */

  void __init setup_replication_mask(void)

  {

  	/* Set only the master cnode's bit.  The master cnode is always 0. */
  	cpus_clear(ktext_repmask);
  	cpu_set(0, ktext_repmask);
  
  #ifdef CONFIG_REPLICATE_KTEXT
  #ifndef CONFIG_MAPPED_KERNEL
  #error Kernel replication works with mapped kernel support. No calias support.
  #endif

  	{
  		cnodeid_t	cnode;
  
  		for_each_online_node(cnode) {
  			if (cnode == 0)
  				continue;
  			/* Advertise that we have a copy of the kernel */
  			cpu_set(cnode, ktext_repmask);
  		}

  	}
  #endif
  	/* Set up a GDA pointer to the replication mask. */
  	GDA->g_ktext_repmask = &ktext_repmask;
  }
  
  
  static __init void set_ktext_source(nasid_t client_nasid, nasid_t server_nasid)
  {

  	kern_vars_t *kvp;

  	kvp = &hub_data(client_nasid)->kern_vars;
  
  	KERN_VARS_ADDR(client_nasid) = (unsigned long)kvp;
  
  	kvp->kv_magic = KV_MAGIC;
  	kvp->kv_ro_nasid = server_nasid;
  	kvp->kv_rw_nasid = master_nasid;
  	kvp->kv_ro_baseaddr = NODE_CAC_BASE(server_nasid);
  	kvp->kv_rw_baseaddr = NODE_CAC_BASE(master_nasid);
  	printk("REPLICATION: ON nasid %d, ktext from nasid %d, kdata from nasid %d
  ", client_nasid, server_nasid, master_nasid);
  }
  
  /* XXX - When the BTE works, we should use it instead of this. */
  static __init void copy_kernel(nasid_t dest_nasid)
  {
  	unsigned long dest_kern_start, source_start, source_end, kern_size;
  
  	source_start = (unsigned long) _stext;
  	source_end = (unsigned long) _etext;
  	kern_size = source_end - source_start;
  
  	dest_kern_start = CHANGE_ADDR_NASID(MAPPED_KERN_RO_TO_K0(source_start),
  					    dest_nasid);
  	memcpy((void *)dest_kern_start, (void *)source_start, kern_size);
  }
  
  void __init replicate_kernel_text()
  {
  	cnodeid_t cnode;
  	nasid_t client_nasid;
  	nasid_t server_nasid;
  
  	server_nasid = master_nasid;
  
  	/* Record where the master node should get its kernel text */
  	set_ktext_source(master_nasid, master_nasid);
  
  	for_each_online_node(cnode) {
  		if (cnode == 0)
  			continue;
  		client_nasid = COMPACT_TO_NASID_NODEID(cnode);
  
  		/* Check if this node should get a copy of the kernel */
  		if (cpu_isset(cnode, ktext_repmask)) {
  			server_nasid = client_nasid;
  			copy_kernel(server_nasid);
  		}
  
  		/* Record where this node should get its kernel text */
  		set_ktext_source(client_nasid, server_nasid);
  	}
  }
  
  /*
   * Return pfn of first free page of memory on a node. PROM may allocate
   * data structures on the first couple of pages of the first slot of each
   * node. If this is the case, getfirstfree(node) > getslotstart(node, 0).
   */
  pfn_t node_getfirstfree(cnodeid_t cnode)
  {
  	unsigned long loadbase = REP_BASE;
  	nasid_t nasid = COMPACT_TO_NASID_NODEID(cnode);
  	unsigned long offset;
  
  #ifdef CONFIG_MAPPED_KERNEL
  	loadbase += 16777216;
  #endif
  	offset = PAGE_ALIGN((unsigned long)(&_end)) - loadbase;
  	if ((cnode == 0) || (cpu_isset(cnode, ktext_repmask)))
  		return (TO_NODE(nasid, offset) >> PAGE_SHIFT);
  	else
  		return (KDM_TO_PHYS(PAGE_ALIGN(SYMMON_STK_ADDR(nasid, 0))) >>
  								PAGE_SHIFT);
  }