/*
   * cbe_regs.c
   *
   * Accessor routines for the various MMIO register blocks of the CBE
   *
   * (c) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
   */
  
  #include <linux/percpu.h>
  #include <linux/types.h>
  #include <linux/export.h>
  #include <linux/of_device.h>
  #include <linux/of_platform.h>
  
  #include <asm/io.h>
  #include <asm/pgtable.h>
  #include <asm/prom.h>
  #include <asm/ptrace.h>
  #include <asm/cell-regs.h>
  
  /*
   * Current implementation uses "cpu" nodes. We build our own mapping
   * array of cpu numbers to cpu nodes locally for now to allow interrupt
   * time code to have a fast path rather than call of_get_cpu_node(). If
   * we implement cpu hotplug, we'll have to install an appropriate norifier
   * in order to release references to the cpu going away
   */
  static struct cbe_regs_map
  {
  	struct device_node *cpu_node;
  	struct device_node *be_node;
  	struct cbe_pmd_regs __iomem *pmd_regs;
  	struct cbe_iic_regs __iomem *iic_regs;
  	struct cbe_mic_tm_regs __iomem *mic_tm_regs;
  	struct cbe_pmd_shadow_regs pmd_shadow_regs;
  } cbe_regs_maps[MAX_CBE];
  static int cbe_regs_map_count;
  
  static struct cbe_thread_map
  {
  	struct device_node *cpu_node;
  	struct device_node *be_node;
  	struct cbe_regs_map *regs;
  	unsigned int thread_id;
  	unsigned int cbe_id;
  } cbe_thread_map[NR_CPUS];
  
  static cpumask_t cbe_local_mask[MAX_CBE] = { [0 ... MAX_CBE-1] = {CPU_BITS_NONE} };
  static cpumask_t cbe_first_online_cpu = { CPU_BITS_NONE };
  
  static struct cbe_regs_map *cbe_find_map(struct device_node *np)
  {
  	int i;
  	struct device_node *tmp_np;
  
  	if (strcasecmp(np->type, "spe")) {
  		for (i = 0; i < cbe_regs_map_count; i++)
  			if (cbe_regs_maps[i].cpu_node == np ||
  			    cbe_regs_maps[i].be_node == np)
  				return &cbe_regs_maps[i];
  		return NULL;
  	}
  
  	if (np->data)
  		return np->data;
  
  	/* walk up path until cpu or be node was found */
  	tmp_np = np;
  	do {
  		tmp_np = tmp_np->parent;
  		/* on a correct devicetree we wont get up to root */
  		BUG_ON(!tmp_np);
  	} while (strcasecmp(tmp_np->type, "cpu") &&
  		 strcasecmp(tmp_np->type, "be"));
  
  	np->data = cbe_find_map(tmp_np);
  
  	return np->data;
  }
  
  struct cbe_pmd_regs __iomem *cbe_get_pmd_regs(struct device_node *np)
  {
  	struct cbe_regs_map *map = cbe_find_map(np);
  	if (map == NULL)
  		return NULL;
  	return map->pmd_regs;
  }
  EXPORT_SYMBOL_GPL(cbe_get_pmd_regs);
  
  struct cbe_pmd_regs __iomem *cbe_get_cpu_pmd_regs(int cpu)
  {
  	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  	if (map == NULL)
  		return NULL;
  	return map->pmd_regs;
  }
  EXPORT_SYMBOL_GPL(cbe_get_cpu_pmd_regs);
  
  struct cbe_pmd_shadow_regs *cbe_get_pmd_shadow_regs(struct device_node *np)
  {
  	struct cbe_regs_map *map = cbe_find_map(np);
  	if (map == NULL)
  		return NULL;
  	return &map->pmd_shadow_regs;
  }
  
  struct cbe_pmd_shadow_regs *cbe_get_cpu_pmd_shadow_regs(int cpu)
  {
  	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  	if (map == NULL)
  		return NULL;
  	return &map->pmd_shadow_regs;
  }
  
  struct cbe_iic_regs __iomem *cbe_get_iic_regs(struct device_node *np)
  {
  	struct cbe_regs_map *map = cbe_find_map(np);
  	if (map == NULL)
  		return NULL;
  	return map->iic_regs;
  }
  
  struct cbe_iic_regs __iomem *cbe_get_cpu_iic_regs(int cpu)
  {
  	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  	if (map == NULL)
  		return NULL;
  	return map->iic_regs;
  }
  
  struct cbe_mic_tm_regs __iomem *cbe_get_mic_tm_regs(struct device_node *np)
  {
  	struct cbe_regs_map *map = cbe_find_map(np);
  	if (map == NULL)
  		return NULL;
  	return map->mic_tm_regs;
  }
  
  struct cbe_mic_tm_regs __iomem *cbe_get_cpu_mic_tm_regs(int cpu)
  {
  	struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  	if (map == NULL)
  		return NULL;
  	return map->mic_tm_regs;
  }
  EXPORT_SYMBOL_GPL(cbe_get_cpu_mic_tm_regs);
  
  u32 cbe_get_hw_thread_id(int cpu)
  {
  	return cbe_thread_map[cpu].thread_id;
  }
  EXPORT_SYMBOL_GPL(cbe_get_hw_thread_id);
  
  u32 cbe_cpu_to_node(int cpu)
  {
  	return cbe_thread_map[cpu].cbe_id;
  }
  EXPORT_SYMBOL_GPL(cbe_cpu_to_node);
  
  u32 cbe_node_to_cpu(int node)
  {
  	return cpumask_first(&cbe_local_mask[node]);
  
  }
  EXPORT_SYMBOL_GPL(cbe_node_to_cpu);
  
  static struct device_node *cbe_get_be_node(int cpu_id)
  {
  	struct device_node *np;
  
  	for_each_node_by_type (np, "be") {
  		int len,i;
  		const phandle *cpu_handle;
  
  		cpu_handle = of_get_property(np, "cpus", &len);
  
  		/*
  		 * the CAB SLOF tree is non compliant, so we just assume
  		 * there is only one node
  		 */
  		if (WARN_ON_ONCE(!cpu_handle))
  			return np;
  
  		for (i=0; i<len; i++)
  			if (of_find_node_by_phandle(cpu_handle[i]) == of_get_cpu_node(cpu_id, NULL))
  				return np;
  	}
  
  	return NULL;
  }
  
  void __init cbe_fill_regs_map(struct cbe_regs_map *map)
  {
  	if(map->be_node) {
  		struct device_node *be, *np;
  
  		be = map->be_node;
  
  		for_each_node_by_type(np, "pervasive")
  			if (of_get_parent(np) == be)
  				map->pmd_regs = of_iomap(np, 0);
  
  		for_each_node_by_type(np, "CBEA-Internal-Interrupt-Controller")
  			if (of_get_parent(np) == be)
  				map->iic_regs = of_iomap(np, 2);
  
  		for_each_node_by_type(np, "mic-tm")
  			if (of_get_parent(np) == be)
  				map->mic_tm_regs = of_iomap(np, 0);
  	} else {
  		struct device_node *cpu;
  		/* That hack must die die die ! */
  		const struct address_prop {
  			unsigned long address;
  			unsigned int len;
  		} __attribute__((packed)) *prop;
  
  		cpu = map->cpu_node;
  
  		prop = of_get_property(cpu, "pervasive", NULL);
  		if (prop != NULL)
  			map->pmd_regs = ioremap(prop->address, prop->len);
  
  		prop = of_get_property(cpu, "iic", NULL);
  		if (prop != NULL)
  			map->iic_regs = ioremap(prop->address, prop->len);
  
  		prop = of_get_property(cpu, "mic-tm", NULL);
  		if (prop != NULL)
  			map->mic_tm_regs = ioremap(prop->address, prop->len);
  	}
  }
  
  
  void __init cbe_regs_init(void)
  {
  	int i;
  	unsigned int thread_id;
  	struct device_node *cpu;
  
  	/* Build local fast map of CPUs */
  	for_each_possible_cpu(i) {
  		cbe_thread_map[i].cpu_node = of_get_cpu_node(i, &thread_id);
  		cbe_thread_map[i].be_node = cbe_get_be_node(i);
  		cbe_thread_map[i].thread_id = thread_id;
  	}
  
  	/* Find maps for each device tree CPU */
  	for_each_node_by_type(cpu, "cpu") {
  		struct cbe_regs_map *map;
  		unsigned int cbe_id;
  
  		cbe_id = cbe_regs_map_count++;
  		map = &cbe_regs_maps[cbe_id];
  
  		if (cbe_regs_map_count > MAX_CBE) {
  			printk(KERN_ERR "cbe_regs: More BE chips than supported"
  			       "!
  ");
  			cbe_regs_map_count--;
  			of_node_put(cpu);
  			return;
  		}
  		map->cpu_node = cpu;
  
  		for_each_possible_cpu(i) {
  			struct cbe_thread_map *thread = &cbe_thread_map[i];
  
  			if (thread->cpu_node == cpu) {
  				thread->regs = map;
  				thread->cbe_id = cbe_id;
  				map->be_node = thread->be_node;
  				cpumask_set_cpu(i, &cbe_local_mask[cbe_id]);
  				if(thread->thread_id == 0)
  					cpumask_set_cpu(i, &cbe_first_online_cpu);
  			}
  		}
  
  		cbe_fill_regs_map(map);
  	}
  }