/* * 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); /* ** 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); }