linux/include/asm-powerpc/floppy.h
Benjamin Herrenschmidt 3d5134ee83 [POWERPC] Rewrite IO allocation & mapping on powerpc64
This rewrites pretty much from scratch the handling of MMIO and PIO
space allocations on powerpc64.  The main goals are:

 - Get rid of imalloc and use more common code where possible
 - Simplify the current mess so that PIO space is allocated and
   mapped in a single place for PCI bridges
 - Handle allocation constraints of PIO for all bridges including
   hot plugged ones within the 2GB space reserved for IO ports,
   so that devices on hotplugged busses will now work with drivers
   that assume IO ports fit in an int.
 - Cleanup and separate tracking of the ISA space in the reserved
   low 64K of IO space. No ISA -> Nothing mapped there.

I booted a cell blade with IDE on PIO and MMIO and a dual G5 so
far, that's it :-)

With this patch, all allocations are done using the code in
mm/vmalloc.c, though we use the low level __get_vm_area with
explicit start/stop constraints in order to manage separate
areas for vmalloc/vmap, ioremap, and PCI IOs.

This greatly simplifies a lot of things, as you can see in the
diffstat of that patch :-)

A new pair of functions pcibios_map/unmap_io_space() now replace
all of the previous code that used to manipulate PCI IOs space.
The allocation is done at mapping time, which is now called from
scan_phb's, just before the devices are probed (instead of after,
which is by itself a bug fix). The only other caller is the PCI
hotplug code for hot adding PCI-PCI bridges (slots).

imalloc is gone, as is the "sub-allocation" thing, but I do beleive
that hotplug should still work in the sense that the space allocation
is always done by the PHB, but if you unmap a child bus of this PHB
(which seems to be possible), then the code should properly tear
down all the HPTE mappings for that area of the PHB allocated IO space.

I now always reserve the first 64K of IO space for the bridge with
the ISA bus on it. I have moved the code for tracking ISA in a separate
file which should also make it smarter if we ever are capable of
hot unplugging or re-plugging an ISA bridge.

This should have a side effect on platforms like powermac where VGA IOs
will no longer work. This is done on purpose though as they would have
worked semi-randomly before. The idea at this point is to isolate drivers
that might need to access those and fix them by providing a proper
function to obtain an offset to the legacy IOs of a given bus.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-14 22:29:56 +10:00

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 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+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(isa_bridge_pcidev, bus_addr, prev_size, prev_dir);
bus_addr = 0;
}
if (!bus_addr) /* need to map it */
bus_addr = pci_map_single(isa_bridge_pcidev, 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(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 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 */