/*
 * Architecture specific parts of the Floppy driver
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1995
 */
#ifndef __ASM_I386_FLOPPY_H
#define __ASM_I386_FLOPPY_H

#include <linux/vmalloc.h>


/*
 * The DMA channel used by the floppy controller cannot access data at
 * addresses >= 16MB
 *
 * Went back to the 1MB limit, as some people had problems with the floppy
 * driver otherwise. It doesn't matter much for performance anyway, as most
 * floppy accesses go through the track buffer.
 */
#define _CROSS_64KB(a,s,vdma) \
(!(vdma) && ((unsigned long)(a)/K_64 != ((unsigned long)(a) + (s) - 1) / K_64))

#define CROSS_64KB(a,s) _CROSS_64KB(a,s,use_virtual_dma & 1)


#define SW fd_routine[use_virtual_dma&1]
#define CSW fd_routine[can_use_virtual_dma & 1]


#define fd_inb(port)                    inb_p(port)
#define fd_outb(port,value)             outb_p(port,value)

#define fd_request_dma()        CSW._request_dma(FLOPPY_DMA,"floppy")
#define fd_free_dma()           CSW._free_dma(FLOPPY_DMA)
#define fd_enable_irq()         enable_irq(FLOPPY_IRQ)
#define fd_disable_irq()        disable_irq(FLOPPY_IRQ)
#define fd_free_irq()           free_irq(FLOPPY_IRQ, NULL)
#define fd_get_dma_residue()    SW._get_dma_residue(FLOPPY_DMA)
#define fd_dma_mem_alloc(size)  SW._dma_mem_alloc(size)
#define fd_dma_setup(addr, size, mode, io) SW._dma_setup(addr, size, mode, io)

#define FLOPPY_CAN_FALLBACK_ON_NODMA

static int virtual_dma_count;
static int virtual_dma_residue;
static char *virtual_dma_addr;
static int virtual_dma_mode;
static int doing_pdma;

static void floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
{
        register unsigned char st;

#undef TRACE_FLPY_INT
#define NO_FLOPPY_ASSEMBLER

#ifdef TRACE_FLPY_INT
        static int calls=0;
        static int bytes=0;
        static int dma_wait=0;
#endif
        if(!doing_pdma) {
                floppy_interrupt(irq, dev_id, regs);
                return;
        }

#ifdef TRACE_FLPY_INT
        if(!calls)
                bytes = virtual_dma_count;
#endif

#ifndef NO_FLOPPY_ASSEMBLER
        __asm__ (
       "testl %1,%1"
        "je 3f"
"1:     inb %w4,%b0"
        "andb $160,%b0"
        "cmpb $160,%b0"
        "jne 2f"
        "incw %w4"
        "testl %3,%3"
        "jne 4f"
        "inb %w4,%b0"
        "movb %0,(%2)"
        "jmp 5f"
"4:     movb (%2),%0"
        "outb %b0,%w4"
"5:     decw %w4"
        "outb %0,$0x80"
        "decl %1"
        "incl %2"
        "testl %1,%1"
        "jne 1b"
"3:     inb %w4,%b0"
"2:     "
       : "=a" ((char) st), 
       "=c" ((long) virtual_dma_count), 
       "=S" ((long) virtual_dma_addr)
       : "b" ((long) virtual_dma_mode),
       "d" ((short) virtual_dma_port+4), 
       "1" ((long) virtual_dma_count),
       "2" ((long) virtual_dma_addr));
#else   
        {
                register int lcount;
                register char *lptr;

                st = 1;
                for(lcount=virtual_dma_count, lptr=virtual_dma_addr; 
                    lcount; lcount--, lptr++) {
                        st=inb(virtual_dma_port+4) & 0xa0 ;
                        if(st != 0xa0) 
                                break;
                        if(virtual_dma_mode)
                                outb_p(*lptr, virtual_dma_port+5);
                        else
                                *lptr = inb_p(virtual_dma_port+5);
                }
                virtual_dma_count = lcount;
                virtual_dma_addr = lptr;
                st = inb(virtual_dma_port+4);
        }
#endif

#ifdef TRACE_FLPY_INT
        calls++;
#endif
        if(st == 0x20)
                return;
        if(!(st & 0x20)) {
                virtual_dma_residue += virtual_dma_count;
                virtual_dma_count=0;
#ifdef TRACE_FLPY_INT
                printk("count=%x, residue=%x calls=%d bytes=%d dma_wait=%d\n", 
                       virtual_dma_count, virtual_dma_residue, calls, bytes,
                       dma_wait);
                calls = 0;
                dma_wait=0;
#endif
                doing_pdma = 0;
                floppy_interrupt(irq, dev_id, regs);
                return;
        }
#ifdef TRACE_FLPY_INT
        if(!virtual_dma_count)
                dma_wait++;
#endif
}

static void fd_disable_dma(void)
{
        if(! (can_use_virtual_dma & 1))
                disable_dma(FLOPPY_DMA);
        doing_pdma = 0;
        virtual_dma_residue += virtual_dma_count;
        virtual_dma_count=0;
}

static int vdma_request_dma(unsigned int dmanr, const char * device_id)
{
        return 0;
}

static void vdma_nop(unsigned int dummy)
{
}


static int vdma_get_dma_residue(unsigned int dummy)
{
        return virtual_dma_count + virtual_dma_residue;
}


static int fd_request_irq(void)
{
        if(can_use_virtual_dma)
                return request_irq(FLOPPY_IRQ, floppy_hardint,SA_INTERRUPT,
                                                   "floppy", NULL);
        else
                return request_irq(FLOPPY_IRQ, floppy_interrupt,
                                                   SA_INTERRUPT|SA_SAMPLE_RANDOM,
                                                   "floppy", NULL);     

}

static unsigned long dma_mem_alloc(unsigned long size)
{
        return __get_dma_pages(GFP_KERNEL,get_order(size));
}


static unsigned long vdma_mem_alloc(unsigned long size)
{
        return (unsigned long) vmalloc(size);

}

#define nodma_mem_alloc(size) vdma_mem_alloc(size)

static void _fd_dma_mem_free(unsigned long addr, unsigned long size)
{
        if((unsigned int) addr >= (unsigned int) high_memory)
                return vfree((void *)addr);
        else
                free_pages(addr, get_order(size));              
}

#define fd_dma_mem_free(addr, size)  _fd_dma_mem_free(addr, size) 

static void _fd_chose_dma_mode(char *addr, unsigned long size)
{
        if(can_use_virtual_dma == 2) {
                if((unsigned int) addr >= (unsigned int) high_memory ||
                   virt_to_bus(addr) >= 0x1000000 ||
                   _CROSS_64KB(addr, size, 0))
                        use_virtual_dma = 1;
                else
                        use_virtual_dma = 0;
        } else {
                use_virtual_dma = can_use_virtual_dma & 1;
        }
}

#define fd_chose_dma_mode(addr, size) _fd_chose_dma_mode(addr, size)


static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
{
        doing_pdma = 1;
        virtual_dma_port = io;
        virtual_dma_mode = (mode  == DMA_MODE_WRITE);
        virtual_dma_addr = addr;
        virtual_dma_count = size;
        virtual_dma_residue = 0;
        return 0;
}

static int hard_dma_setup(char *addr, unsigned long size, int mode, int io)
{
#ifdef FLOPPY_SANITY_CHECK
        if (CROSS_64KB(addr, size)) {
                printk("DMA crossing 64-K boundary %p-%p\n", addr, addr+size);
                return -1;
        }
#endif
        /* actual, physical DMA */
        doing_pdma = 0;
        clear_dma_ff(FLOPPY_DMA);
        set_dma_mode(FLOPPY_DMA,mode);
        set_dma_addr(FLOPPY_DMA,virt_to_bus(addr));
        set_dma_count(FLOPPY_DMA,size);
        enable_dma(FLOPPY_DMA);
        return 0;
}

struct fd_routine_l {
        int (*_request_dma)(unsigned int dmanr, const char * device_id);
        void (*_free_dma)(unsigned int dmanr);
        int (*_get_dma_residue)(unsigned int dummy);
        unsigned long (*_dma_mem_alloc) (unsigned long size);
        int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
} fd_routine[] = {
        {
                request_dma,
                free_dma,
                get_dma_residue,
                dma_mem_alloc,
                hard_dma_setup
        },
        {
                vdma_request_dma,
                vdma_nop,
                vdma_get_dma_residue,
                vdma_mem_alloc,
                vdma_dma_setup
        }
};


static int FDC1 = 0x3f0;
static int FDC2 = -1;

/*
 * Floppy types are stored in the rtc's CMOS RAM and so rtc_lock
 * is needed to prevent corrupted CMOS RAM in case "insmod floppy"
 * coincides with another rtc CMOS user.                Paul G.
 */
#define FLOPPY0_TYPE    ({                              \
        unsigned long flags;                            \
        unsigned char val;                              \
        spin_lock_irqsave(&rtc_lock, flags);            \
        val = (CMOS_READ(0x10) >> 4) & 15;              \
        spin_unlock_irqrestore(&rtc_lock, flags);       \
        val;                                            \
})

#define FLOPPY1_TYPE    ({                              \
        unsigned long flags;                            \
        unsigned char val;                              \
        spin_lock_irqsave(&rtc_lock, flags);            \
        val = CMOS_READ(0x10) & 15;                     \
        spin_unlock_irqrestore(&rtc_lock, flags);       \
        val;                                            \
})

#define N_FDC 2
#define N_DRIVE 8

#define FLOPPY_MOTOR_MASK 0xf0

#define AUTO_DMA

#define EXTRA_FLOPPY_PARAMS

#endif /* __ASM_I386_FLOPPY_H */