//  IBM_PROLOG_BEGIN_TAG
//  This is an automatically generated prolog.
//
//  $Source: src/kernel/exception.C $
//
//  IBM CONFIDENTIAL
//
//  COPYRIGHT International Business Machines Corp. 2010 - 2011
//
//  p1
//
//  Object Code Only (OCO) source materials
//  Licensed Internal Code Source Materials
//  IBM HostBoot Licensed Internal Code
//
//  The source code for this program is not published or other-
//  wise divested of its trade secrets, irrespective of what has
//  been deposited with the U.S. Copyright Office.
//
//  Origin: 30
//
//  IBM_PROLOG_END
#include <assert.h>
#include <kernel/types.h>
#include <kernel/console.H>
#include <kernel/task.H>
#include <kernel/taskmgr.H>
#include <arch/ppc.H>
#include <kernel/vmmmgr.H>
#include <kernel/cpuid.H>
#include <kernel/intmsghandler.H>

namespace ExceptionHandles
{
    bool HvEmulation(task_t*);
}

const uint64_t EXCEPTION_SRR1_MASK 	= 0x00000000783F0000;
const uint64_t EXCEPTION_SRR1_HVEMUL	= 0x0000000000080000;

extern "C"
void kernel_execute_prog_ex()
{
    task_t* t = TaskManager::getCurrentTask();
    uint64_t exception = getSRR1() & EXCEPTION_SRR1_MASK;

    bool handled = false;
    switch(exception)
    {
	case EXCEPTION_SRR1_HVEMUL:
	    handled = ExceptionHandles::HvEmulation(t);
	    break;
    }
    if (!handled)
    {
	printk("Program exception, killing task %d\n", t->tid);
	TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
    }
}

const uint64_t EXCEPTION_DSISR_MASK	= 0x0000000040000000;
const uint64_t EXCEPTION_DSISR_PTEMISS  = 0x0000000040000000;

extern "C"
void kernel_execute_data_storage()
{
    task_t* t = TaskManager::getCurrentTask();
    uint64_t exception = getDSISR() & EXCEPTION_DSISR_MASK;

    bool handled = false;
    switch(exception)
    {
	case EXCEPTION_DSISR_PTEMISS:
	    handled = VmmManager::pteMiss(t, getDAR());
	    break;
    }
    if (!handled)
    {
	printk("Data Storage exception on %d: %lx, %lx @ %p\n",
	       t->tid, getDAR(), getDSISR(), t->context.nip);
	TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
    }
}

extern "C"
void kernel_execute_data_segment()
{
    task_t* t = TaskManager::getCurrentTask();
    printk("Data Segment exception, killing task %d\n", t->tid);
    TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
}

const uint64_t EXCEPTION_SRR1_INSTR_MASK    = 0x0000000040000000;
const uint64_t EXCEPTION_SRR1_INSTR_PTEMISS = 0x0000000040000000;

extern "C"
void kernel_execute_inst_storage()
{
    task_t* t = TaskManager::getCurrentTask();
    uint64_t exception = getSRR1() & EXCEPTION_SRR1_INSTR_MASK;

    bool handled = false;
    switch (exception)
    {
        case EXCEPTION_SRR1_INSTR_PTEMISS:
            handled = VmmManager::pteMiss(t, getSRR0());
            break;
    }
    if (!handled)
    {
        printk("Inst Storage exception on %d: %lx, %lx\n",
               t->tid, getSRR0(), getSRR1());
	TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
    }
}

extern "C"
void kernel_execute_inst_segment()
{
    task_t* t = TaskManager::getCurrentTask();
    printk("Inst Segment exception, killing task %d\n", t->tid);
    TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
}

extern "C"
void kernel_execute_alignment()
{
    task_t* t = TaskManager::getCurrentTask();
    printk("Alignment exception, killing task %d\n", t->tid);
    TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
}

extern "C"
void kernel_execute_hype_emu_assist()
{
    task_t* t = TaskManager::getCurrentTask();
    printk("HypeEmu: Illegal instruction in task %d\n"
           "\tHSSR0 = %lx, HEIR = %lx\n", t->tid, getHSRR0(), getHEIR());
    TaskManager::endTask(t, NULL, TASK_STATUS_CRASHED);
}

namespace ExceptionHandles
{
    bool HvEmulation(task_t* t)
    {
	/*printk("NIP = %lx : Inst = %x\n",
	       t->context.nip,
	       (*(uint32_t*)t->context.nip));*/

	uint32_t instruction = *(uint32_t*)t->context.nip;

	    // check for mfsprg3
	if ((instruction & 0xfc1fffff) == 0x7c1342a6)
	{
	    t->context.gprs[(instruction & 0x03E00000) >> 21] =
		    (uint64_t) t;
	    t->context.nip = (void*) (((uint64_t)t->context.nip)+4);
	    return true;
	}

	return false;
    }

}

extern "C"
void kernel_execute_fp_unavail()
{
    task_t* t = TaskManager::getCurrentTask();

    if (t->fp_context)
    {
        printk("Error: FP unavailable while task has FP-context.\n");
        kassert(t->fp_context == NULL);
    }
    else
    {
        // Enable FP by creating a FP context.
        // Context switch code will handle the rest.
        t->fp_context = new context_fp_t;
        memset(t->fp_context, '\0', sizeof(context_fp_t));
    }
}

const uint64_t EXCEPTION_HSRR1_SOFTPATCH_MASK   = 0x0000000000100000;
const uint64_t EXCEPTION_HSRR1_SOFTPATCH_DENORM = 0x0000000000100000;

extern "C" void p7_softpatch_denorm_assist(context_fp_t*);

extern "C"
void kernel_execute_softpatch()
{
    task_t* t = TaskManager::getCurrentTask();

    if ((getHSRR1() & EXCEPTION_HSRR1_SOFTPATCH_MASK) ==
        EXCEPTION_HSRR1_SOFTPATCH_DENORM)
    {
        if (t->fp_context == NULL)
        {
            printk("Error: Task took Denorm-assist without FP active.\n");
            kassert(t->fp_context != NULL);
        }

        switch (CpuID::getCpuType())
        {
            case CORE_POWER7:
            case CORE_POWER7_PLUS:
            case CORE_POWER8_SALERNO: // @TODO: Verify same procedure.
            case CORE_POWER8_VENICE:  // @TODO: Verify same procedure.
            case CORE_UNKNOWN:
                p7_softpatch_denorm_assist(t->fp_context);
                break;
        }
    }
}

extern "C"
void kernel_execute_machine_check()
{
    task_t* t = TaskManager::getCurrentTask();
    printk("Machine check in %d on %ld:\n"
           "\tSRR0 = %lx, SRR1 = %lx\n"
           "\tDSISR = %lx, DAR = %lx\n",
           t->tid, getPIR(),
           getSRR0(), getSRR1(), getDSISR(), getDAR());
    kassert(false);
}

extern "C"
void kernel_execute_external()
{
    // SRR0 set to the effective addr the thread
    // would have attempted to execute next
    // SRR1 [33:36,42:47] set to zero
    //      all others copied from MSR
    InterruptMsgHdlr::handleInterrupt();
}