root/arch/powerpc/include/asm/floppy.h
/*
 * 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_POWERPC_FLOPPY_H
#define __ASM_POWERPC_FLOPPY_H
#ifdef __KERNEL__

#include <asm/machdep.h>

#define fd_inb(base, reg)               inb_p((base) + (reg))
#define fd_outb(value, base, reg)       outb_p(value, (base) + (reg))

#define fd_enable_dma()         enable_dma(FLOPPY_DMA)
#define fd_disable_dma()         fd_ops->_disable_dma(FLOPPY_DMA)
#define fd_free_dma()           fd_ops->_free_dma(FLOPPY_DMA)
#define fd_clear_dma_ff()       clear_dma_ff(FLOPPY_DMA)
#define fd_set_dma_mode(mode)   set_dma_mode(FLOPPY_DMA, mode)
#define fd_set_dma_count(count) set_dma_count(FLOPPY_DMA, count)
#define fd_get_dma_residue()    fd_ops->_get_dma_residue(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);

#include <linux/pci.h>
#include <asm/ppc-pci.h>        /* for isa_bridge_pcidev */

#define fd_dma_setup(addr,size,mode,io) fd_ops->_dma_setup(addr,size,mode,io)

static int fd_request_dma(void);

struct fd_dma_ops {
        void (*_disable_dma)(unsigned int dmanr);
        void (*_free_dma)(unsigned int dmanr);
        int (*_get_dma_residue)(unsigned int dummy);
        int (*_dma_setup)(char *addr, unsigned long size, int mode, int io);
};

static int virtual_dma_count;
static int virtual_dma_residue;
static char *virtual_dma_addr;
static int virtual_dma_mode;
static int doing_vdma;
static struct fd_dma_ops *fd_ops;

static irqreturn_t floppy_hardint(int irq, void *dev_id)
{
        unsigned char st;
        int lcount;
        char *lptr;

        if (!doing_vdma)
                return floppy_interrupt(irq, dev_id);


        st = 1;
        for (lcount=virtual_dma_count, lptr=virtual_dma_addr;
             lcount; lcount--, lptr++) {
                st = inb(virtual_dma_port + FD_STATUS);
                st &= STATUS_DMA | STATUS_READY;
                if (st != (STATUS_DMA | STATUS_READY))
                        break;
                if (virtual_dma_mode)
                        outb_p(*lptr, virtual_dma_port + FD_DATA);
                else
                        *lptr = inb_p(virtual_dma_port + FD_DATA);
        }
        virtual_dma_count = lcount;
        virtual_dma_addr = lptr;
        st = inb(virtual_dma_port + FD_STATUS);

        if (st == STATUS_DMA)
                return IRQ_HANDLED;
        if (!(st & STATUS_DMA)) {
                virtual_dma_residue += virtual_dma_count;
                virtual_dma_count=0;
                doing_vdma = 0;
                floppy_interrupt(irq, dev_id);
                return IRQ_HANDLED;
        }
        return IRQ_HANDLED;
}

static void vdma_disable_dma(unsigned int dummy)
{
        doing_vdma = 0;
        virtual_dma_residue += virtual_dma_count;
        virtual_dma_count=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,
                                   0, "floppy", NULL);
        else
                return request_irq(FLOPPY_IRQ, floppy_interrupt,
                                   0, "floppy", NULL);
}

static int vdma_dma_setup(char *addr, unsigned long size, int mode, int io)
{
        doing_vdma = 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)
{
        static unsigned long prev_size;
        static dma_addr_t bus_addr = 0;
        static char *prev_addr;
        static int prev_dir;
        int dir;

        doing_vdma = 0;
        dir = (mode == DMA_MODE_READ) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;

        if (bus_addr 
            && (addr != prev_addr || size != prev_size || dir != prev_dir)) {
                /* different from last time -- unmap prev */
                dma_unmap_single(&isa_bridge_pcidev->dev, bus_addr, prev_size,
                                 prev_dir);
                bus_addr = 0;
        }

        if (!bus_addr) {        /* need to map it */
                bus_addr = dma_map_single(&isa_bridge_pcidev->dev, addr, size,
                                          dir);
                if (dma_mapping_error(&isa_bridge_pcidev->dev, bus_addr))
                        return -ENOMEM;
        }

        /* remember this one as prev */
        prev_addr = addr;
        prev_size = size;
        prev_dir = dir;

        fd_clear_dma_ff();
        fd_set_dma_mode(mode);
        set_dma_addr(FLOPPY_DMA, bus_addr);
        fd_set_dma_count(size);
        virtual_dma_port = io;
        fd_enable_dma();

        return 0;
}

static struct fd_dma_ops real_dma_ops =
{
        ._disable_dma = disable_dma,
        ._free_dma = free_dma,
        ._get_dma_residue = get_dma_residue,
        ._dma_setup = hard_dma_setup
};

static struct fd_dma_ops virt_dma_ops =
{
        ._disable_dma = vdma_disable_dma,
        ._free_dma = vdma_nop,
        ._get_dma_residue = vdma_get_dma_residue,
        ._dma_setup = vdma_dma_setup
};

static int fd_request_dma(void)
{
        if (can_use_virtual_dma & 1) {
                fd_ops = &virt_dma_ops;
                return 0;
        }
        else {
                fd_ops = &real_dma_ops;
                return request_dma(FLOPPY_DMA, "floppy");
        }
}

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

/*
 * Again, the CMOS information not available
 */
#define FLOPPY0_TYPE 6
#define FLOPPY1_TYPE 0

#define N_FDC 2                 /* Don't change this! */
#define N_DRIVE 8

#define EXTRA_FLOPPY_PARAMS

#endif /* __KERNEL__ */
#endif /* __ASM_POWERPC_FLOPPY_H */