/*
   * SN Platform GRU Driver
   *
   *              FILE OPERATIONS & DRIVER INITIALIZATION
   *
   * This file supports the user system call for file open, close, mmap, etc.
   * This also incudes the driver initialization code.
   *
   *  Copyright (c) 2008 Silicon Graphics, Inc.  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; either version 2 of the License, or
   *  (at your option) any later version.
   *
   *  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.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program; if not, write to the Free Software
   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   */
  
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/slab.h>
  #include <linux/mm.h>
  #include <linux/io.h>
  #include <linux/spinlock.h>
  #include <linux/device.h>
  #include <linux/miscdevice.h>
  #include <linux/interrupt.h>
  #include <linux/proc_fs.h>
  #include <linux/uaccess.h>
  #ifdef CONFIG_X86_64
  #include <asm/uv/uv_irq.h>
  #endif
  #include <asm/uv/uv.h>
  #include "gru.h"
  #include "grulib.h"
  #include "grutables.h"
  
  #include <asm/uv/uv_hub.h>
  #include <asm/uv/uv_mmrs.h>
  
  struct gru_blade_state *gru_base[GRU_MAX_BLADES] __read_mostly;
  unsigned long gru_start_paddr __read_mostly;
  void *gru_start_vaddr __read_mostly;
  unsigned long gru_end_paddr __read_mostly;
  unsigned int gru_max_gids __read_mostly;
  struct gru_stats_s gru_stats;
  
  /* Guaranteed user available resources on each node */
  static int max_user_cbrs, max_user_dsr_bytes;
  
  static struct miscdevice gru_miscdev;
  
  
  /*
   * gru_vma_close
   *
   * Called when unmapping a device mapping. Frees all gru resources
   * and tables belonging to the vma.
   */
  static void gru_vma_close(struct vm_area_struct *vma)
  {
  	struct gru_vma_data *vdata;
  	struct gru_thread_state *gts;
  	struct list_head *entry, *next;
  
  	if (!vma->vm_private_data)
  		return;
  
  	vdata = vma->vm_private_data;
  	vma->vm_private_data = NULL;
  	gru_dbg(grudev, "vma %p, file %p, vdata %p
  ", vma, vma->vm_file,
  				vdata);
  	list_for_each_safe(entry, next, &vdata->vd_head) {
  		gts =
  		    list_entry(entry, struct gru_thread_state, ts_next);
  		list_del(&gts->ts_next);
  		mutex_lock(&gts->ts_ctxlock);
  		if (gts->ts_gru)
  			gru_unload_context(gts, 0);
  		mutex_unlock(&gts->ts_ctxlock);
  		gts_drop(gts);
  	}
  	kfree(vdata);
  	STAT(vdata_free);
  }
  
  /*
   * gru_file_mmap
   *
   * Called when mmapping the device.  Initializes the vma with a fault handler
   * and private data structure necessary to allocate, track, and free the
   * underlying pages.
   */
  static int gru_file_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if ((vma->vm_flags & (VM_SHARED | VM_WRITE)) != (VM_SHARED | VM_WRITE))
  		return -EPERM;
  
  	if (vma->vm_start & (GRU_GSEG_PAGESIZE - 1) ||
  				vma->vm_end & (GRU_GSEG_PAGESIZE - 1))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP | VM_LOCKED |
  			 VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP;
  	vma->vm_page_prot = PAGE_SHARED;
  	vma->vm_ops = &gru_vm_ops;
  
  	vma->vm_private_data = gru_alloc_vma_data(vma, 0);
  	if (!vma->vm_private_data)
  		return -ENOMEM;
  
  	gru_dbg(grudev, "file %p, vaddr 0x%lx, vma %p, vdata %p
  ",
  		file, vma->vm_start, vma, vma->vm_private_data);
  	return 0;
  }
  
  /*
   * Create a new GRU context
   */
  static int gru_create_new_context(unsigned long arg)
  {
  	struct gru_create_context_req req;
  	struct vm_area_struct *vma;
  	struct gru_vma_data *vdata;
  	int ret = -EINVAL;
  
  	if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
  		return -EFAULT;
  
  	if (req.data_segment_bytes > max_user_dsr_bytes)
  		return -EINVAL;
  	if (req.control_blocks > max_user_cbrs || !req.maximum_thread_count)
  		return -EINVAL;
  
  	if (!(req.options & GRU_OPT_MISS_MASK))
  		req.options |= GRU_OPT_MISS_FMM_INTR;
  
  	down_write(&current->mm->mmap_sem);
  	vma = gru_find_vma(req.gseg);
  	if (vma) {
  		vdata = vma->vm_private_data;
  		vdata->vd_user_options = req.options;
  		vdata->vd_dsr_au_count =
  		    GRU_DS_BYTES_TO_AU(req.data_segment_bytes);
  		vdata->vd_cbr_au_count = GRU_CB_COUNT_TO_AU(req.control_blocks);
  		vdata->vd_tlb_preload_count = req.tlb_preload_count;
  		ret = 0;
  	}
  	up_write(&current->mm->mmap_sem);
  
  	return ret;
  }
  
  /*
   * Get GRU configuration info (temp - for emulator testing)
   */
  static long gru_get_config_info(unsigned long arg)
  {
  	struct gru_config_info info;
  	int nodesperblade;
  
  	if (num_online_nodes() > 1 &&
  			(uv_node_to_blade_id(1) == uv_node_to_blade_id(0)))
  		nodesperblade = 2;
  	else
  		nodesperblade = 1;
  	memset(&info, 0, sizeof(info));
  	info.cpus = num_online_cpus();
  	info.nodes = num_online_nodes();
  	info.blades = info.nodes / nodesperblade;
  	info.chiplets = GRU_CHIPLETS_PER_BLADE * info.blades;
  
  	if (copy_to_user((void __user *)arg, &info, sizeof(info)))
  		return -EFAULT;
  	return 0;
  }
  
  /*
   * gru_file_unlocked_ioctl
   *
   * Called to update file attributes via IOCTL calls.
   */
  static long gru_file_unlocked_ioctl(struct file *file, unsigned int req,
  				    unsigned long arg)
  {
  	int err = -EBADRQC;
  
  	gru_dbg(grudev, "file %p, req 0x%x, 0x%lx
  ", file, req, arg);
  
  	switch (req) {
  	case GRU_CREATE_CONTEXT:
  		err = gru_create_new_context(arg);
  		break;
  	case GRU_SET_CONTEXT_OPTION:
  		err = gru_set_context_option(arg);
  		break;
  	case GRU_USER_GET_EXCEPTION_DETAIL:
  		err = gru_get_exception_detail(arg);
  		break;
  	case GRU_USER_UNLOAD_CONTEXT:
  		err = gru_user_unload_context(arg);
  		break;
  	case GRU_USER_FLUSH_TLB:
  		err = gru_user_flush_tlb(arg);
  		break;
  	case GRU_USER_CALL_OS:
  		err = gru_handle_user_call_os(arg);
  		break;
  	case GRU_GET_GSEG_STATISTICS:
  		err = gru_get_gseg_statistics(arg);
  		break;
  	case GRU_KTEST:
  		err = gru_ktest(arg);
  		break;
  	case GRU_GET_CONFIG_INFO:
  		err = gru_get_config_info(arg);
  		break;
  	case GRU_DUMP_CHIPLET_STATE:
  		err = gru_dump_chiplet_request(arg);
  		break;
  	}
  	return err;
  }
  
  /*
   * Called at init time to build tables for all GRUs that are present in the
   * system.
   */
  static void gru_init_chiplet(struct gru_state *gru, unsigned long paddr,
  			     void *vaddr, int blade_id, int chiplet_id)
  {
  	spin_lock_init(&gru->gs_lock);
  	spin_lock_init(&gru->gs_asid_lock);
  	gru->gs_gru_base_paddr = paddr;
  	gru->gs_gru_base_vaddr = vaddr;
  	gru->gs_gid = blade_id * GRU_CHIPLETS_PER_BLADE + chiplet_id;
  	gru->gs_blade = gru_base[blade_id];
  	gru->gs_blade_id = blade_id;
  	gru->gs_chiplet_id = chiplet_id;
  	gru->gs_cbr_map = (GRU_CBR_AU == 64) ? ~0 : (1UL << GRU_CBR_AU) - 1;
  	gru->gs_dsr_map = (1UL << GRU_DSR_AU) - 1;
  	gru->gs_asid_limit = MAX_ASID;
  	gru_tgh_flush_init(gru);
  	if (gru->gs_gid >= gru_max_gids)
  		gru_max_gids = gru->gs_gid + 1;
  	gru_dbg(grudev, "bid %d, gid %d, vaddr %p (0x%lx)
  ",
  		blade_id, gru->gs_gid, gru->gs_gru_base_vaddr,
  		gru->gs_gru_base_paddr);
  }
  
  static int gru_init_tables(unsigned long gru_base_paddr, void *gru_base_vaddr)
  {
  	int pnode, nid, bid, chip;
  	int cbrs, dsrbytes, n;
  	int order = get_order(sizeof(struct gru_blade_state));
  	struct page *page;
  	struct gru_state *gru;
  	unsigned long paddr;
  	void *vaddr;
  
  	max_user_cbrs = GRU_NUM_CB;
  	max_user_dsr_bytes = GRU_NUM_DSR_BYTES;
  	for_each_possible_blade(bid) {
  		pnode = uv_blade_to_pnode(bid);
  		nid = uv_blade_to_memory_nid(bid);/* -1 if no memory on blade */
  		page = alloc_pages_node(nid, GFP_KERNEL, order);
  		if (!page)
  			goto fail;
  		gru_base[bid] = page_address(page);
  		memset(gru_base[bid], 0, sizeof(struct gru_blade_state));
  		gru_base[bid]->bs_lru_gru = &gru_base[bid]->bs_grus[0];
  		spin_lock_init(&gru_base[bid]->bs_lock);
  		init_rwsem(&gru_base[bid]->bs_kgts_sema);
  
  		dsrbytes = 0;
  		cbrs = 0;
  		for (gru = gru_base[bid]->bs_grus, chip = 0;
  				chip < GRU_CHIPLETS_PER_BLADE;
  				chip++, gru++) {
  			paddr = gru_chiplet_paddr(gru_base_paddr, pnode, chip);
  			vaddr = gru_chiplet_vaddr(gru_base_vaddr, pnode, chip);
  			gru_init_chiplet(gru, paddr, vaddr, bid, chip);
  			n = hweight64(gru->gs_cbr_map) * GRU_CBR_AU_SIZE;
  			cbrs = max(cbrs, n);
  			n = hweight64(gru->gs_dsr_map) * GRU_DSR_AU_BYTES;
  			dsrbytes = max(dsrbytes, n);
  		}
  		max_user_cbrs = min(max_user_cbrs, cbrs);
  		max_user_dsr_bytes = min(max_user_dsr_bytes, dsrbytes);
  	}
  
  	return 0;
  
  fail:
  	for (bid--; bid >= 0; bid--)
  		free_pages((unsigned long)gru_base[bid], order);
  	return -ENOMEM;
  }
  
  static void gru_free_tables(void)
  {
  	int bid;
  	int order = get_order(sizeof(struct gru_state) *
  			      GRU_CHIPLETS_PER_BLADE);
  
  	for (bid = 0; bid < GRU_MAX_BLADES; bid++)
  		free_pages((unsigned long)gru_base[bid], order);
  }
  
  static unsigned long gru_chiplet_cpu_to_mmr(int chiplet, int cpu, int *corep)
  {
  	unsigned long mmr = 0;
  	int core;
  
  	/*
  	 * We target the cores of a blade and not the hyperthreads themselves.
  	 * There is a max of 8 cores per socket and 2 sockets per blade,
  	 * making for a max total of 16 cores (i.e., 16 CPUs without
  	 * hyperthreading and 32 CPUs with hyperthreading).
  	 */
  	core = uv_cpu_core_number(cpu) + UV_MAX_INT_CORES * uv_cpu_socket_number(cpu);
  	if (core >= GRU_NUM_TFM || uv_cpu_ht_number(cpu))
  		return 0;
  
  	if (chiplet == 0) {
  		mmr = UVH_GR0_TLB_INT0_CONFIG +
  		    core * (UVH_GR0_TLB_INT1_CONFIG - UVH_GR0_TLB_INT0_CONFIG);
  	} else if (chiplet == 1) {
  		mmr = UVH_GR1_TLB_INT0_CONFIG +
  		    core * (UVH_GR1_TLB_INT1_CONFIG - UVH_GR1_TLB_INT0_CONFIG);
  	} else {
  		BUG();
  	}
  
  	*corep = core;
  	return mmr;
  }
  
  #ifdef CONFIG_IA64
  
  static int gru_irq_count[GRU_CHIPLETS_PER_BLADE];
  
  static void gru_noop(struct irq_data *d)
  {
  }
  
  static struct irq_chip gru_chip[GRU_CHIPLETS_PER_BLADE] = {
  	[0 ... GRU_CHIPLETS_PER_BLADE - 1] {
  		.irq_mask	= gru_noop,
  		.irq_unmask	= gru_noop,
  		.irq_ack	= gru_noop
  	}
  };
  
  static int gru_chiplet_setup_tlb_irq(int chiplet, char *irq_name,
  			irq_handler_t irq_handler, int cpu, int blade)
  {
  	unsigned long mmr;
  	int irq = IRQ_GRU + chiplet;
  	int ret, core;
  
  	mmr = gru_chiplet_cpu_to_mmr(chiplet, cpu, &core);
  	if (mmr == 0)
  		return 0;
  
  	if (gru_irq_count[chiplet] == 0) {
  		gru_chip[chiplet].name = irq_name;
  		ret = irq_set_chip(irq, &gru_chip[chiplet]);
  		if (ret) {
  			printk(KERN_ERR "%s: set_irq_chip failed, errno=%d
  ",
  			       GRU_DRIVER_ID_STR, -ret);
  			return ret;
  		}
  
  		ret = request_irq(irq, irq_handler, 0, irq_name, NULL);
  		if (ret) {
  			printk(KERN_ERR "%s: request_irq failed, errno=%d
  ",
  			       GRU_DRIVER_ID_STR, -ret);
  			return ret;
  		}
  	}
  	gru_irq_count[chiplet]++;
  
  	return 0;
  }
  
  static void gru_chiplet_teardown_tlb_irq(int chiplet, int cpu, int blade)
  {
  	unsigned long mmr;
  	int core, irq = IRQ_GRU + chiplet;
  
  	if (gru_irq_count[chiplet] == 0)
  		return;
  
  	mmr = gru_chiplet_cpu_to_mmr(chiplet, cpu, &core);
  	if (mmr == 0)
  		return;
  
  	if (--gru_irq_count[chiplet] == 0)
  		free_irq(irq, NULL);
  }
  
  #elif defined CONFIG_X86_64
  
  static int gru_chiplet_setup_tlb_irq(int chiplet, char *irq_name,
  			irq_handler_t irq_handler, int cpu, int blade)
  {
  	unsigned long mmr;
  	int irq, core;
  	int ret;
  
  	mmr = gru_chiplet_cpu_to_mmr(chiplet, cpu, &core);
  	if (mmr == 0)
  		return 0;
  
  	irq = uv_setup_irq(irq_name, cpu, blade, mmr, UV_AFFINITY_CPU);
  	if (irq < 0) {
  		printk(KERN_ERR "%s: uv_setup_irq failed, errno=%d
  ",
  		       GRU_DRIVER_ID_STR, -irq);
  		return irq;
  	}
  
  	ret = request_irq(irq, irq_handler, 0, irq_name, NULL);
  	if (ret) {
  		uv_teardown_irq(irq);
  		printk(KERN_ERR "%s: request_irq failed, errno=%d
  ",
  		       GRU_DRIVER_ID_STR, -ret);
  		return ret;
  	}
  	gru_base[blade]->bs_grus[chiplet].gs_irq[core] = irq;
  	return 0;
  }
  
  static void gru_chiplet_teardown_tlb_irq(int chiplet, int cpu, int blade)
  {
  	int irq, core;
  	unsigned long mmr;
  
  	mmr = gru_chiplet_cpu_to_mmr(chiplet, cpu, &core);
  	if (mmr) {
  		irq = gru_base[blade]->bs_grus[chiplet].gs_irq[core];
  		if (irq) {
  			free_irq(irq, NULL);
  			uv_teardown_irq(irq);
  		}
  	}
  }
  
  #endif
  
  static void gru_teardown_tlb_irqs(void)
  {
  	int blade;
  	int cpu;
  
  	for_each_online_cpu(cpu) {
  		blade = uv_cpu_to_blade_id(cpu);
  		gru_chiplet_teardown_tlb_irq(0, cpu, blade);
  		gru_chiplet_teardown_tlb_irq(1, cpu, blade);
  	}
  	for_each_possible_blade(blade) {
  		if (uv_blade_nr_possible_cpus(blade))
  			continue;
  		gru_chiplet_teardown_tlb_irq(0, 0, blade);
  		gru_chiplet_teardown_tlb_irq(1, 0, blade);
  	}
  }
  
  static int gru_setup_tlb_irqs(void)
  {
  	int blade;
  	int cpu;
  	int ret;
  
  	for_each_online_cpu(cpu) {
  		blade = uv_cpu_to_blade_id(cpu);
  		ret = gru_chiplet_setup_tlb_irq(0, "GRU0_TLB", gru0_intr, cpu, blade);
  		if (ret != 0)
  			goto exit1;
  
  		ret = gru_chiplet_setup_tlb_irq(1, "GRU1_TLB", gru1_intr, cpu, blade);
  		if (ret != 0)
  			goto exit1;
  	}
  	for_each_possible_blade(blade) {
  		if (uv_blade_nr_possible_cpus(blade))
  			continue;
  		ret = gru_chiplet_setup_tlb_irq(0, "GRU0_TLB", gru_intr_mblade, 0, blade);
  		if (ret != 0)
  			goto exit1;
  
  		ret = gru_chiplet_setup_tlb_irq(1, "GRU1_TLB", gru_intr_mblade, 0, blade);
  		if (ret != 0)
  			goto exit1;
  	}
  
  	return 0;
  
  exit1:
  	gru_teardown_tlb_irqs();
  	return ret;
  }
  
  /*
   * gru_init
   *
   * Called at boot or module load time to initialize the GRUs.
   */
  static int __init gru_init(void)
  {
  	int ret;
  
  	if (!is_uv_system() || (is_uvx_hub() && !is_uv2_hub()))
  		return 0;
  
  #if defined CONFIG_IA64
  	gru_start_paddr = 0xd000000000UL; /* ZZZZZZZZZZZZZZZZZZZ fixme */
  #else
  	gru_start_paddr = uv_read_local_mmr(UVH_RH_GAM_GRU_OVERLAY_CONFIG_MMR) &
  				0x7fffffffffffUL;
  #endif
  	gru_start_vaddr = __va(gru_start_paddr);
  	gru_end_paddr = gru_start_paddr + GRU_MAX_BLADES * GRU_SIZE;
  	printk(KERN_INFO "GRU space: 0x%lx - 0x%lx
  ",
  	       gru_start_paddr, gru_end_paddr);
  	ret = misc_register(&gru_miscdev);
  	if (ret) {
  		printk(KERN_ERR "%s: misc_register failed
  ",
  		       GRU_DRIVER_ID_STR);
  		goto exit0;
  	}
  
  	ret = gru_proc_init();
  	if (ret) {
  		printk(KERN_ERR "%s: proc init failed
  ", GRU_DRIVER_ID_STR);
  		goto exit1;
  	}
  
  	ret = gru_init_tables(gru_start_paddr, gru_start_vaddr);
  	if (ret) {
  		printk(KERN_ERR "%s: init tables failed
  ", GRU_DRIVER_ID_STR);
  		goto exit2;
  	}
  
  	ret = gru_setup_tlb_irqs();
  	if (ret != 0)
  		goto exit3;
  
  	gru_kservices_init();
  
  	printk(KERN_INFO "%s: v%s
  ", GRU_DRIVER_ID_STR,
  	       GRU_DRIVER_VERSION_STR);
  	return 0;
  
  exit3:
  	gru_free_tables();
  exit2:
  	gru_proc_exit();
  exit1:
  	misc_deregister(&gru_miscdev);
  exit0:
  	return ret;
  
  }
  
  static void __exit gru_exit(void)
  {
  	if (!is_uv_system())
  		return;
  
  	gru_teardown_tlb_irqs();
  	gru_kservices_exit();
  	gru_free_tables();
  	misc_deregister(&gru_miscdev);
  	gru_proc_exit();
  }
  
  static const struct file_operations gru_fops = {
  	.owner		= THIS_MODULE,
  	.unlocked_ioctl	= gru_file_unlocked_ioctl,
  	.mmap		= gru_file_mmap,
  	.llseek		= noop_llseek,
  };
  
  static struct miscdevice gru_miscdev = {
  	.minor		= MISC_DYNAMIC_MINOR,
  	.name		= "gru",
  	.fops		= &gru_fops,
  };
  
  const struct vm_operations_struct gru_vm_ops = {
  	.close		= gru_vma_close,
  	.fault		= gru_fault,
  };
  
  #ifndef MODULE
  fs_initcall(gru_init);
  #else
  module_init(gru_init);
  #endif
  module_exit(gru_exit);
  
  module_param(gru_options, ulong, 0644);
  MODULE_PARM_DESC(gru_options, "Various debug options");
  
  MODULE_AUTHOR("Silicon Graphics, Inc.");
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION(GRU_DRIVER_ID_STR GRU_DRIVER_VERSION_STR);
  MODULE_VERSION(GRU_DRIVER_VERSION_STR);