kernel-ark/include/asm-powerpc/floppy.h
Pavel Fedin 9ea8b7c96f [POWERPC] Virtual DMA support for floppy driver for new powerpc architecture
During ppc64+ppc merge virtual DMA code for floppy driver was not
ported.  This patch restores virtual DMA support for floppy in new
powerpc target.

It is necessary at least on Pegasos and AmigaOne machines for the
floppy drive to function.  ISA DMA controller works incorrectly there
due to its addressing limitations.

Virtual DMA mode is activated by floppy=nodma option passed to the
kernel (or module).  There's no automatic switch like on i386.

Signed-off-by: Pavel Fedin <sonic_amiga@rambler.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-13 15:35:52 +11:00

216 lines
5.0 KiB
C

/*
* 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(port) inb_p(port)
#define fd_outb(value,port) outb_p(value,port)
#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_cacheflush(addr,size) /* nothing */
#define fd_free_irq() free_irq(FLOPPY_IRQ, NULL);
#include <linux/pci.h>
#include <asm/ppc-pci.h> /* for ppc64_isabridge_dev */
#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+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);
if (st == 0x20)
return IRQ_HANDLED;
if (!(st & 0x20)) {
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,
IRQF_DISABLED, "floppy", NULL);
else
return request_irq(FLOPPY_IRQ, floppy_interrupt,
IRQF_DISABLED, "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) ? PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE;
if (bus_addr
&& (addr != prev_addr || size != prev_size || dir != prev_dir)) {
/* different from last time -- unmap prev */
pci_unmap_single(ppc64_isabridge_dev, bus_addr, prev_size, prev_dir);
bus_addr = 0;
}
if (!bus_addr) /* need to map it */
bus_addr = pci_map_single(ppc64_isabridge_dev, addr, size, dir);
/* remember this one as prev */
prev_addr = addr;
prev_size = size;
prev_dir = dir;
fd_clear_dma_ff();
fd_cacheflush(addr, size);
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()
{
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 FLOPPY_MOTOR_MASK 0xf0
/*
* The PowerPC has no problems with floppy DMA crossing 64k borders.
*/
#define CROSS_64KB(a,s) (0)
#define EXTRA_FLOPPY_PARAMS
#endif /* __KERNEL__ */
#endif /* __ASM_POWERPC_FLOPPY_H */