arch/powerpc/platforms/cell/cbe_regs.c

   1 /*
   2  * cbe_regs.c
   3  *
   4  * Accessor routines for the various MMIO register blocks of the CBE
   5  *
   6  * (c) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
   7  */
   8
   9
  10 #include <linux/config.h>
  11 #include <linux/percpu.h>
  12 #include <linux/types.h>
  13
  14 #include <asm/io.h>
  15 #include <asm/pgtable.h>
  16 #include <asm/prom.h>
  17 #include <asm/ptrace.h>
  18
  19 #include "cbe_regs.h"
  20
  21 #define MAX_CBE         2
  22
  23 /*
  24  * Current implementation uses "cpu" nodes. We build our own mapping
  25  * array of cpu numbers to cpu nodes locally for now to allow interrupt
  26  * time code to have a fast path rather than call of_get_cpu_node(). If
  27  * we implement cpu hotplug, we'll have to install an appropriate norifier
  28  * in order to release references to the cpu going away
  29  */
  30 static struct cbe_regs_map
  31 {
  32         struct device_node *cpu_node;
  33         struct cbe_pmd_regs __iomem *pmd_regs;
  34         struct cbe_iic_regs __iomem *iic_regs;
  35 } cbe_regs_maps[MAX_CBE];
  36 static int cbe_regs_map_count;
  37
  38 static struct cbe_thread_map
  39 {
  40         struct device_node *cpu_node;
  41         struct cbe_regs_map *regs;
  42 } cbe_thread_map[NR_CPUS];
  43
  44 static struct cbe_regs_map *cbe_find_map(struct device_node *np)
  45 {
  46         int i;
  47
  48         for (i = 0; i < cbe_regs_map_count; i++)
  49                 if (cbe_regs_maps[i].cpu_node == np)
  50                         return &cbe_regs_maps[i];
  51         return NULL;
  52 }
  53
  54 struct cbe_pmd_regs __iomem *cbe_get_pmd_regs(struct device_node *np)
  55 {
  56         struct cbe_regs_map *map = cbe_find_map(np);
  57         if (map == NULL)
  58                 return NULL;
  59         return map->pmd_regs;
  60 }
  61
  62 struct cbe_pmd_regs __iomem *cbe_get_cpu_pmd_regs(int cpu)
  63 {
  64         struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  65         if (map == NULL)
  66                 return NULL;
  67         return map->pmd_regs;
  68 }
  69
  70
  71 struct cbe_iic_regs __iomem *cbe_get_iic_regs(struct device_node *np)
  72 {
  73         struct cbe_regs_map *map = cbe_find_map(np);
  74         if (map == NULL)
  75                 return NULL;
  76         return map->iic_regs;
  77 }
  78 struct cbe_iic_regs __iomem *cbe_get_cpu_iic_regs(int cpu)
  79 {
  80         struct cbe_regs_map *map = cbe_thread_map[cpu].regs;
  81         if (map == NULL)
  82                 return NULL;
  83         return map->iic_regs;
  84 }
  85
  86 void __init cbe_regs_init(void)
  87 {
  88         int i;
  89         struct device_node *cpu;
  90
  91         /* Build local fast map of CPUs */
  92         for_each_possible_cpu(i)
  93                 cbe_thread_map[i].cpu_node = of_get_cpu_node(i, NULL);
  94
  95         /* Find maps for each device tree CPU */
  96         for_each_node_by_type(cpu, "cpu") {
  97                 struct cbe_regs_map *map = &cbe_regs_maps[cbe_regs_map_count++];
  98
  99                 /* That hack must die die die ! */
 100                 const struct address_prop {
 101                         unsigned long address;
 102                         unsigned int len;
 103                 } __attribute__((packed)) *prop;
 104
 105
 106                 if (cbe_regs_map_count > MAX_CBE) {
 107                         printk(KERN_ERR "cbe_regs: More BE chips than supported"
 108                                "!\n");
 109                         cbe_regs_map_count--;
 110                         return;
 111                 }
 112                 map->cpu_node = cpu;
 113                 for_each_possible_cpu(i)
 114                         if (cbe_thread_map[i].cpu_node == cpu)
 115                                 cbe_thread_map[i].regs = map;
 116
 117                 prop = get_property(cpu, "pervasive", NULL);
 118                 if (prop != NULL)
 119                         map->pmd_regs = ioremap(prop->address, prop->len);
 120
 121                 prop = get_property(cpu, "iic", NULL);
 122                 if (prop != NULL)
 123                         map->iic_regs = ioremap(prop->address, prop->len);
 124         }
 125 }
 126