/*
   * Copyright (C) 2012 CERN (www.cern.ch)
   * Author: Alessandro Rubini <rubini@gnudd.com>
   *
   * Released according to the GNU GPL, version 2 or any later version.
   *
   * This work is part of the White Rabbit project, a research effort led
   * by CERN, the European Institute for Nuclear Research.
   */
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/fmc.h>
  #include <linux/sdb.h>
  #include <linux/err.h>
  #include <linux/fmc-sdb.h>
  #include <asm/byteorder.h>
  
  static uint32_t __sdb_rd(struct fmc_device *fmc, unsigned long address,
  			int convert)
  {
  	uint32_t res = fmc_readl(fmc, address);
  	if (convert)
  		return __be32_to_cpu(res);
  	return res;
  }
  
  static struct sdb_array *__fmc_scan_sdb_tree(struct fmc_device *fmc,
  					     unsigned long sdb_addr,
  					     unsigned long reg_base, int level)
  {
  	uint32_t onew;
  	int i, j, n, convert = 0;
  	struct sdb_array *arr, *sub;
  
  	onew = fmc_readl(fmc, sdb_addr);
  	if (onew == SDB_MAGIC) {
  		/* Uh! If we are little-endian, we must convert */
  		if (SDB_MAGIC != __be32_to_cpu(SDB_MAGIC))
  			convert = 1;
  	} else if (onew == __be32_to_cpu(SDB_MAGIC)) {
  		/* ok, don't convert */
  	} else {
  		return ERR_PTR(-ENOENT);
  	}
  	/* So, the magic was there: get the count from offset 4*/
  	onew = __sdb_rd(fmc, sdb_addr + 4, convert);
  	n = __be16_to_cpu(*(uint16_t *)&onew);
  	arr = kzalloc(sizeof(*arr), GFP_KERNEL);
  	if (!arr)
  		return ERR_PTR(-ENOMEM);
  	arr->record = kzalloc(sizeof(arr->record[0]) * n, GFP_KERNEL);
  	arr->subtree = kzalloc(sizeof(arr->subtree[0]) * n, GFP_KERNEL);
  	if (!arr->record || !arr->subtree) {
  		kfree(arr->record);
  		kfree(arr->subtree);
  		kfree(arr);
  		return ERR_PTR(-ENOMEM);
  	}
  
  	arr->len = n;
  	arr->level = level;
  	arr->fmc = fmc;
  	for (i = 0; i < n; i++) {
  		union  sdb_record *r;
  
  		for (j = 0; j < sizeof(arr->record[0]); j += 4) {
  			*(uint32_t *)((void *)(arr->record + i) + j) =
  				__sdb_rd(fmc, sdb_addr + (i * 64) + j, convert);
  		}
  		r = &arr->record[i];
  		arr->subtree[i] = ERR_PTR(-ENODEV);
  		if (r->empty.record_type == sdb_type_bridge) {
  			struct sdb_component *c = &r->bridge.sdb_component;
  			uint64_t subaddr = __be64_to_cpu(r->bridge.sdb_child);
  			uint64_t newbase = __be64_to_cpu(c->addr_first);
  
  			subaddr += reg_base;
  			newbase += reg_base;
  			sub = __fmc_scan_sdb_tree(fmc, subaddr, newbase,
  						  level + 1);
  			arr->subtree[i] = sub; /* may be error */
  			if (IS_ERR(sub))
  				continue;
  			sub->parent = arr;
  			sub->baseaddr = newbase;
  		}
  	}
  	return arr;
  }
  
  int fmc_scan_sdb_tree(struct fmc_device *fmc, unsigned long address)
  {
  	struct sdb_array *ret;
  	if (fmc->sdb)
  		return -EBUSY;
  	ret = __fmc_scan_sdb_tree(fmc, address, 0 /* regs */, 0);
  	if (IS_ERR(ret))
  		return PTR_ERR(ret);
  	fmc->sdb = ret;
  	return 0;
  }
  EXPORT_SYMBOL(fmc_scan_sdb_tree);
  
  static void __fmc_sdb_free(struct sdb_array *arr)
  {
  	int i, n;
  
  	if (!arr)
  		return;
  	n = arr->len;
  	for (i = 0; i < n; i++) {
  		if (IS_ERR(arr->subtree[i]))
  			continue;
  		__fmc_sdb_free(arr->subtree[i]);
  	}
  	kfree(arr->record);
  	kfree(arr->subtree);
  	kfree(arr);
  }
  
  int fmc_free_sdb_tree(struct fmc_device *fmc)
  {
  	__fmc_sdb_free(fmc->sdb);
  	fmc->sdb = NULL;
  	return 0;
  }
  EXPORT_SYMBOL(fmc_free_sdb_tree);
  
  /* This helper calls reprogram and inizialized sdb as well */
  int fmc_reprogram(struct fmc_device *fmc, struct fmc_driver *d, char *gw,
  			 int sdb_entry)
  {
  	int ret;
  
  	ret = fmc->op->reprogram(fmc, d, gw);
  	if (ret < 0)
  		return ret;
  	if (sdb_entry < 0)
  		return ret;
  
  	/* We are required to find SDB at a given offset */
  	ret = fmc_scan_sdb_tree(fmc, sdb_entry);
  	if (ret < 0) {
  		dev_err(&fmc->dev, "Can't find SDB at address 0x%x
  ",
  			sdb_entry);
  		return -ENODEV;
  	}
  	fmc_dump_sdb(fmc);
  	return 0;
  }
  EXPORT_SYMBOL(fmc_reprogram);
  
  static void __fmc_show_sdb_tree(const struct fmc_device *fmc,
  				const struct sdb_array *arr)
  {
  	int i, j, n = arr->len, level = arr->level;
  	const struct sdb_array *ap;
  
  	for (i = 0; i < n; i++) {
  		unsigned long base;
  		union  sdb_record *r;
  		struct sdb_product *p;
  		struct sdb_component *c;
  		r = &arr->record[i];
  		c = &r->dev.sdb_component;
  		p = &c->product;
  		base = 0;
  		for (ap = arr; ap; ap = ap->parent)
  			base += ap->baseaddr;
  		dev_info(&fmc->dev, "SDB: ");
  
  		for (j = 0; j < level; j++)
  			printk(KERN_CONT "   ");
  		switch (r->empty.record_type) {
  		case sdb_type_interconnect:
  			printk(KERN_CONT "%08llx:%08x %.19s
  ",
  			       __be64_to_cpu(p->vendor_id),
  			       __be32_to_cpu(p->device_id),
  			       p->name);
  			break;
  		case sdb_type_device:
  			printk(KERN_CONT "%08llx:%08x %.19s (%08llx-%08llx)
  ",
  			       __be64_to_cpu(p->vendor_id),
  			       __be32_to_cpu(p->device_id),
  			       p->name,
  			       __be64_to_cpu(c->addr_first) + base,
  			       __be64_to_cpu(c->addr_last) + base);
  			break;
  		case sdb_type_bridge:
  			printk(KERN_CONT "%08llx:%08x %.19s (bridge: %08llx)
  ",
  			       __be64_to_cpu(p->vendor_id),
  			       __be32_to_cpu(p->device_id),
  			       p->name,
  			       __be64_to_cpu(c->addr_first) + base);
  			if (IS_ERR(arr->subtree[i])) {
  				printk(KERN_CONT "(bridge error %li)
  ",
  				       PTR_ERR(arr->subtree[i]));
  				break;
  			}
  			__fmc_show_sdb_tree(fmc, arr->subtree[i]);
  			break;
  		case sdb_type_integration:
  			printk(KERN_CONT "integration
  ");
  			break;
  		case sdb_type_repo_url:
  			printk(KERN_CONT "repo-url
  ");
  			break;
  		case sdb_type_synthesis:
  			printk(KERN_CONT "synthesis-info
  ");
  			break;
  		case sdb_type_empty:
  			printk(KERN_CONT "empty
  ");
  			break;
  		default:
  			printk(KERN_CONT "UNKNOWN TYPE 0x%02x
  ",
  			       r->empty.record_type);
  			break;
  		}
  	}
  }
  
  void fmc_show_sdb_tree(const struct fmc_device *fmc)
  {
  	if (!fmc->sdb)
  		return;
  	__fmc_show_sdb_tree(fmc, fmc->sdb);
  }
  EXPORT_SYMBOL(fmc_show_sdb_tree);
  
  signed long fmc_find_sdb_device(struct sdb_array *tree,
  				uint64_t vid, uint32_t did, unsigned long *sz)
  {
  	signed long res = -ENODEV;
  	union  sdb_record *r;
  	struct sdb_product *p;
  	struct sdb_component *c;
  	int i, n = tree->len;
  	uint64_t last, first;
  
  	/* FIXME: what if the first interconnect is not at zero? */
  	for (i = 0; i < n; i++) {
  		r = &tree->record[i];
  		c = &r->dev.sdb_component;
  		p = &c->product;
  
  		if (!IS_ERR(tree->subtree[i]))
  			res = fmc_find_sdb_device(tree->subtree[i],
  						  vid, did, sz);
  		if (res >= 0)
  			return res + tree->baseaddr;
  		if (r->empty.record_type != sdb_type_device)
  			continue;
  		if (__be64_to_cpu(p->vendor_id) != vid)
  			continue;
  		if (__be32_to_cpu(p->device_id) != did)
  			continue;
  		/* found */
  		last = __be64_to_cpu(c->addr_last);
  		first = __be64_to_cpu(c->addr_first);
  		if (sz)
  			*sz = (typeof(*sz))(last + 1 - first);
  		return first + tree->baseaddr;
  	}
  	return res;
  }
  EXPORT_SYMBOL(fmc_find_sdb_device);