/*
 * APIC driver for "bigsmp" xAPIC machines with more than 8 virtual CPUs.
 *
 * Drives the local APIC in "clustered mode".
 */
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/smp.h>

#include <asm/apicdef.h>
#include <asm/fixmap.h>
#include <asm/mpspec.h>
#include <asm/apic.h>
#include <asm/ipi.h>

static unsigned bigsmp_get_apic_id(unsigned long x)
{
        return (x >> 24) & 0xFF;
}

static int bigsmp_apic_id_registered(void)
{
        return 1;
}

static unsigned long bigsmp_check_apicid_used(physid_mask_t *map, int apicid)
{
        return 0;
}

static int bigsmp_early_logical_apicid(int cpu)
{
        /* on bigsmp, logical apicid is the same as physical */
        return early_per_cpu(x86_cpu_to_apicid, cpu);
}

static inline unsigned long calculate_ldr(int cpu)
{
        unsigned long val, id;

        val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
        id = per_cpu(x86_bios_cpu_apicid, cpu);
        val |= SET_APIC_LOGICAL_ID(id);

        return val;
}

/*
 * Set up the logical destination ID.
 *
 * Intel recommends to set DFR, LDR and TPR before enabling
 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
 * document number 292116).  So here it goes...
 */
static void bigsmp_init_apic_ldr(void)
{
        unsigned long val;
        int cpu = smp_processor_id();

        apic_write(APIC_DFR, APIC_DFR_FLAT);
        val = calculate_ldr(cpu);
        apic_write(APIC_LDR, val);
}

static void bigsmp_setup_apic_routing(void)
{
        printk(KERN_INFO
                "Enabling APIC mode:  Physflat.  Using %d I/O APICs\n",
                nr_ioapics);
}

static int bigsmp_cpu_present_to_apicid(int mps_cpu)
{
        if (mps_cpu < nr_cpu_ids)
                return (int) per_cpu(x86_bios_cpu_apicid, mps_cpu);

        return BAD_APICID;
}

static void bigsmp_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
{
        /* For clustered we don't have a good way to do this yet - hack */
        physids_promote(0xFFL, retmap);
}

static int bigsmp_check_phys_apicid_present(int phys_apicid)
{
        return 1;
}

static int bigsmp_phys_pkg_id(int cpuid_apic, int index_msb)
{
        return cpuid_apic >> index_msb;
}

static inline void bigsmp_send_IPI_mask(const struct cpumask *mask, int vector)
{
        default_send_IPI_mask_sequence_phys(mask, vector);
}

static void bigsmp_send_IPI_allbutself(int vector)
{
        default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
}

static void bigsmp_send_IPI_all(int vector)
{
        bigsmp_send_IPI_mask(cpu_online_mask, vector);
}

static int dmi_bigsmp; /* can be set by dmi scanners */

static int hp_ht_bigsmp(const struct dmi_system_id *d)
{
        printk(KERN_NOTICE "%s detected: force use of apic=bigsmp\n", d->ident);
        dmi_bigsmp = 1;

        return 0;
}


static const struct dmi_system_id bigsmp_dmi_table[] = {
        { hp_ht_bigsmp, "HP ProLiant DL760 G2",
                {       DMI_MATCH(DMI_BIOS_VENDOR, "HP"),
                        DMI_MATCH(DMI_BIOS_VERSION, "P44-"),
                }
        },

        { hp_ht_bigsmp, "HP ProLiant DL740",
                {       DMI_MATCH(DMI_BIOS_VENDOR, "HP"),
                        DMI_MATCH(DMI_BIOS_VERSION, "P47-"),
                }
        },
        { } /* NULL entry stops DMI scanning */
};

static int probe_bigsmp(void)
{
        if (def_to_bigsmp)
                dmi_bigsmp = 1;
        else
                dmi_check_system(bigsmp_dmi_table);

        return dmi_bigsmp;
}

static struct apic apic_bigsmp = {

        .name                           = "bigsmp",
        .probe                          = probe_bigsmp,
        .acpi_madt_oem_check            = NULL,
        .apic_id_valid                  = default_apic_id_valid,
        .apic_id_registered             = bigsmp_apic_id_registered,

        .irq_delivery_mode              = dest_Fixed,
        /* phys delivery to target CPU: */
        .irq_dest_mode                  = 0,

        .target_cpus                    = default_target_cpus,
        .disable_esr                    = 1,
        .dest_logical                   = 0,
        .check_apicid_used              = bigsmp_check_apicid_used,

        .vector_allocation_domain       = default_vector_allocation_domain,
        .init_apic_ldr                  = bigsmp_init_apic_ldr,

        .ioapic_phys_id_map             = bigsmp_ioapic_phys_id_map,
        .setup_apic_routing             = bigsmp_setup_apic_routing,
        .cpu_present_to_apicid          = bigsmp_cpu_present_to_apicid,
        .apicid_to_cpu_present          = physid_set_mask_of_physid,
        .check_phys_apicid_present      = bigsmp_check_phys_apicid_present,
        .phys_pkg_id                    = bigsmp_phys_pkg_id,

        .get_apic_id                    = bigsmp_get_apic_id,
        .set_apic_id                    = NULL,
        .apic_id_mask                   = 0xFF << 24,

        .cpu_mask_to_apicid_and         = default_cpu_mask_to_apicid_and,

        .send_IPI_mask                  = bigsmp_send_IPI_mask,
        .send_IPI_mask_allbutself       = NULL,
        .send_IPI_allbutself            = bigsmp_send_IPI_allbutself,
        .send_IPI_all                   = bigsmp_send_IPI_all,
        .send_IPI_self                  = default_send_IPI_self,

        .inquire_remote_apic            = default_inquire_remote_apic,

        .read                           = native_apic_mem_read,
        .write                          = native_apic_mem_write,
        .eoi_write                      = native_apic_mem_write,
        .icr_read                       = native_apic_icr_read,
        .icr_write                      = native_apic_icr_write,
        .wait_icr_idle                  = native_apic_wait_icr_idle,
        .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,

        .x86_32_early_logical_apicid    = bigsmp_early_logical_apicid,
};

void __init generic_bigsmp_probe(void)
{
        unsigned int cpu;

        if (!probe_bigsmp())
                return;

        apic = &apic_bigsmp;

        for_each_possible_cpu(cpu) {
                if (early_per_cpu(x86_cpu_to_logical_apicid,
                                  cpu) == BAD_APICID)
                        continue;
                early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
                        bigsmp_early_logical_apicid(cpu);
        }

        pr_info("Overriding APIC driver with %s\n", apic_bigsmp.name);
}

apic_driver(apic_bigsmp);