/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2007 by Karl Kurbjun
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
 
#include "kernel.h"
#include "system.h"
#include "panic.h"

#define default_interrupt(name) \
  extern __attribute__((weak,alias("UIRQ"))) void name (void)

default_interrupt(TIMER0);
default_interrupt(TIMER1);
default_interrupt(TIMER2);
default_interrupt(TIMER3);
default_interrupt(CCD_VD0);
default_interrupt(CCD_VD1);
default_interrupt(CCD_WEN);
default_interrupt(VENC);
default_interrupt(SERIAL0);
default_interrupt(SERIAL1);
default_interrupt(EXT_HOST);
default_interrupt(DSPHINT);
default_interrupt(UART0);
default_interrupt(UART1);
default_interrupt(USB_DMA);
default_interrupt(USB_CORE);
default_interrupt(VLYNQ);
default_interrupt(MTC0);
default_interrupt(MTC1);
default_interrupt(SD_MMC);
default_interrupt(SDIO_MS);
default_interrupt(GIO0);
default_interrupt(GIO1);
default_interrupt(GIO2);
default_interrupt(GIO3);
default_interrupt(GIO4);
default_interrupt(GIO5);
default_interrupt(GIO6);
default_interrupt(GIO7);
default_interrupt(GIO8);
default_interrupt(GIO9);
default_interrupt(GIO10);
default_interrupt(GIO11);
default_interrupt(GIO12);
default_interrupt(GIO13);
default_interrupt(GIO14);
default_interrupt(GIO15);
default_interrupt(PREVIEW0);
default_interrupt(PREVIEW1);
default_interrupt(WATCHDOG);
default_interrupt(I2C);
default_interrupt(CLKC);
default_interrupt(ICE);
default_interrupt(ARMCOM_RX);
default_interrupt(ARMCOM_TX);
default_interrupt(RESERVED);

static void (* const irqvector[])(void) =
{
    TIMER0,TIMER1,TIMER2,TIMER3,CCD_VD0,CCD_VD1,
    CCD_WEN,VENC,SERIAL0,SERIAL1,EXT_HOST,DSPHINT,
    UART0,UART1,USB_DMA,USB_CORE,VLYNQ,MTC0,MTC1,
    SD_MMC,SDIO_MS,GIO0,GIO1,GIO2,GIO3,GIO4,GIO5,
    GIO6,GIO7,GIO8,GIO9,GIO10,GIO11,GIO12,GIO13,
    GIO14,GIO15,PREVIEW0,PREVIEW1,WATCHDOG,I2C,CLKC,
    ICE,ARMCOM_RX,ARMCOM_TX,RESERVED
};

static const char * const irqname[] =
{
    "TIMER0","TIMER1","TIMER2","TIMER3","CCD_VD0","CCD_VD1",
    "CCD_WEN","VENC","SERIAL0","SERIAL1","EXT_HOST","DSPHINT",
    "UART0","UART1","USB_DMA","USB_CORE","VLYNQ","MTC0","MTC1",
    "SD_MMC","SDIO_MS","GIO0","GIO1","GIO2","GIO3","GIO4","GIO5",
    "GIO6","GIO7","GIO8","GIO9","GIO10","GIO11","GIO12","GIO13",
    "GIO14","GIO15","PREVIEW0","PREVIEW1","WATCHDOG","I2C","CLKC",
    "ICE","ARMCOM_RX","ARMCOM_TX","RESERVED"
};

static void UIRQ(void)
{
    unsigned int offset = (IO_INTC_IRQENTRY0>>2)-1;
    panicf("Unhandled IRQ %02X: %s", offset, irqname[offset]);
}

void irq_handler(void) __attribute__((interrupt ("IRQ"), naked));
void irq_handler(void)
{
    /*
     * Based on: linux/arch/arm/kernel/entry-armv.S and system-meg-fx.c
     */

    asm volatile(   "stmfd sp!, {r0-r7, ip, lr} \n"   /* Store context */
                    "sub   sp, sp, #8           \n"); /* Reserve stack */
    irqvector[(IO_INTC_IRQENTRY0>>2)-1]();
    asm volatile(   "add   sp, sp, #8           \n"   /* Cleanup stack   */
                    "ldmfd sp!, {r0-r7, ip, lr} \n"   /* Restore context */
                    "subs  pc, lr, #4           \n"); /* Return from FIQ */
}

void fiq_handler(void) __attribute__((interrupt ("FIQ"), naked));
void fiq_handler(void)
{
    /*
     * Based on: linux/arch/arm/kernel/entry-armv.S and system-meg-fx.c
     */

    asm volatile (
        "sub    lr, lr, #4            \r\n"
        "stmfd  sp!, {r0-r3, ip, lr}  \r\n"
        "mov    r0, #0x00030000       \r\n"
        "ldr    r0, [r0, #0x518]       \r\n"
        "ldr    r1, =irqvector        \r\n"
        "ldr    r1, [r1, r0, lsl #2]  \r\n"
        "mov    lr, pc                \r\n"
        "bx     r1                    \r\n"
        "ldmfd  sp!, {r0-r3, ip, pc}^ \r\n"
    );
}

void system_reboot(void)
{

}

void enable_interrupts (void)
{
    asm volatile ("msr cpsr_c, #0x13" );
}

void system_init(void)
{
    /* taken from linux/arch/arm/mach-itdm320-20/irq.c */

    /* Clearing all FIQs and IRQs. */
    IO_INTC_IRQ0 = 0xFFFF;
    IO_INTC_IRQ1 = 0xFFFF;
    IO_INTC_IRQ2 = 0xFFFF;

    IO_INTC_FIQ0 = 0xFFFF;
    IO_INTC_FIQ1 = 0xFFFF;
    IO_INTC_FIQ2 = 0xFFFF;

    /* Masking all Interrupts. */
    IO_INTC_EINT0 = 0;
    IO_INTC_EINT1 = 0;
    IO_INTC_EINT2 = 0;

    /* Setting INTC to all IRQs. */
    IO_INTC_FISEL0 = 0;
    IO_INTC_FISEL1 = 0;
    IO_INTC_FISEL2 = 0;

    IO_INTC_ENTRY_TBA0 =
    IO_INTC_ENTRY_TBA1 = 0;

    /* set GIO26 (reset pin) to output and low */
    IO_GIO_BITCLR1=(1<<10);
    IO_GIO_DIR1&=~(1<<10);

    enable_interrupts();
}

int system_memory_guard(int newmode)
{
    (void)newmode;
    return 0;
}

#ifdef HAVE_ADJUSTABLE_CPU_FREQ

void set_cpu_frequency(long frequency)
{
    if (frequency == CPUFREQ_MAX)
    {
        asm volatile("mov r0, #0\n"
            "mrc p15, 0, r0, c1, c0, 0\n"
            "orr r0, r0, #3<<30\n" /* set to Asynchronous mode*/
            "mcr p15, 0, r0, c1, c0, 0" : : : "r0");

        FREQ = CPUFREQ_MAX;
    }
    else
    {
        asm volatile("mov r0, #0\n"
            "mrc p15, 0, r0, c1, c0, 0\n"
            "bic r0, r0, #3<<30\n" /* set to FastBus mode*/
            "mcr p15, 0, r0, c1, c0, 0" : : : "r0");

        FREQ = CPUFREQ_NORMAL;
    }
}

#endif