/*
* ccio-rm-dma.c:
* DMA management routines for first generation cache-coherent machines.
* "Real Mode" operation refers to U2/Uturn chip operation. The chip
* can perform coherency checks w/o using the I/O MMU. That's all we
* need until support for more than 4GB phys mem is needed.
*
* This is the trivial case - basically what x86 does.
*
* Drawbacks of using Real Mode are:
* o outbound DMA is slower since one isn't using the prefetching
* U2 can do for outbound DMA.
* o Ability to do scatter/gather in HW is also lost.
* o only known to work with PCX-W processor. (eg C360)
* (PCX-U/U+ are not coherent with U2 in real mode.)
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
*
* Original version/author:
* CVSROOT=:pserver:anonymous@198.186.203.37:/cvsroot/linux-parisc
* cvs -z3 co linux/arch/parisc/kernel/dma-rm.c
*
* (C) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
*
*
* Adopted for The Puffin Group's parisc-linux port by Grant Grundler.
* (C) Copyright 2000 Grant Grundler <grundler@puffin.external.hp.com>
*
*/
#include <linux/types.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/hardware.h>
#include <asm/page.h>
/* Only chose "ccio" since that's what HP-UX calls it....
** Make it easier for folks to migrate from one to the other :^)
*/
#define MODULE_NAME "ccio"
#define U2_IOA_RUNWAY 0x580
#define U2_BC_GSC 0x501
#define UTURN_IOA_RUNWAY 0x581
#define UTURN_BC_GSC 0x502
#define IS_U2(id) ( \
(((id)->hw_type == HPHW_IOA) && ((id)->hversion == U2_IOA_RUNWAY)) || \
(((id)->hw_type == HPHW_BCPORT) && ((id)->hversion == U2_BC_GSC)) \
)
#define IS_UTURN(id) ( \
(((id)->hw_type == HPHW_IOA) && ((id)->hversion == UTURN_IOA_RUNWAY)) || \
(((id)->hw_type == HPHW_BCPORT) && ((id)->hversion == UTURN_BC_GSC)) \
)
static int ccio_dma_supported( struct pci_dev *dev, u64 mask)
{
if (dev == NULL) {
printk(KERN_ERR MODULE_NAME ": EISA/ISA/et al not supported\n");
BUG();
return(0);
}
/* only support 32-bit devices (ie PCI/GSC) */
return((int) (mask >= 0xffffffffUL));
}
static void *ccio_alloc_consistent(struct pci_dev *dev, size_t size,
dma_addr_t *handle)
{
void *ret;
ret = (void *)__get_free_pages(GFP_ATOMIC, get_order(size));
if (ret != NULL) {
memset(ret, 0, size);
*handle = virt_to_phys(ret);
}
return ret;
}
static void ccio_free_consistent(struct pci_dev *dev, size_t size,
void *vaddr, dma_addr_t handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
static dma_addr_t ccio_map_single(struct pci_dev *dev, void *ptr, size_t size,
int direction)
{
return virt_to_phys(ptr);
}
static void ccio_unmap_single(struct pci_dev *dev, dma_addr_t dma_addr,
size_t size, int direction)
{
/* Nothing to do */
}
static int ccio_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
{
int tmp = nents;
/* KISS: map each buffer separately. */
while (nents) {
sg_dma_address(sglist) = ccio_map_single(dev, sglist->address, sglist->length, direction);
sg_dma_len(sglist) = sglist->length;
nents--;
sglist++;
}
return tmp;
}
static void ccio_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
{
#if 0
while (nents) {
ccio_unmap_single(dev, sg_dma_address(sglist), sg_dma_len(sglist), direction);
nents--;
sglist++;
}
return;
#else
/* Do nothing (copied from current ccio_unmap_single() :^) */
#endif
}
static struct pci_dma_ops ccio_ops = {
ccio_dma_supported,
ccio_alloc_consistent,
ccio_free_consistent,
ccio_map_single,
ccio_unmap_single,
ccio_map_sg,
ccio_unmap_sg,
NULL, /* dma_sync_single_for_cpu : NOP for U2 */
NULL, /* dma_sync_single_for_device : NOP for U2 */
NULL, /* dma_sync_sg_for_cpu : ditto */
NULL, /* dma_sync_sg_for_device : ditto */
};
/*
** Determine if u2 should claim this chip (return 0) or not (return 1).
** If so, initialize the chip and tell other partners in crime they
** have work to do.
*/
static int
ccio_probe(struct parisc_device *dev)
{
printk(KERN_INFO "%s found %s at 0x%lx\n", MODULE_NAME,
dev->id.hversion == U2_BC_GSC ? "U2" : "UTurn",
dev->hpa.start);
/*
** FIXME - should check U2 registers to verify it's really running
** in "Real Mode".
*/
#if 0
/* will need this for "Virtual Mode" operation */
ccio_hw_init(ccio_dev);
ccio_common_init(ccio_dev);
#endif
hppa_dma_ops = &ccio_ops;
return 0;
}
static struct parisc_device_id ccio_tbl[] = {
{ HPHW_BCPORT, HVERSION_REV_ANY_ID, U2_BC_GSC, 0xc },
{ HPHW_BCPORT, HVERSION_REV_ANY_ID, UTURN_BC_GSC, 0xc },
{ 0, }
};
static struct parisc_driver ccio_driver = {
.name = "U2/Uturn",
.id_table = ccio_tbl,
.probe = ccio_probe,
};
void __init ccio_init(void)
{
register_parisc_driver(&ccio_driver);
}
