cbe_regs.c

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/*
 * cbe_regs.c
 *
 * Accessor routines for the various MMIO register blocks of the CBE
 *
 * (c) 2006 Benjamin Herrenschmidt <[email protected]>, 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"
                   "!\n");
            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);
    }
}