- 根目录:
- arch
- ia64
- sn
- pci
- pci_dma.c
/*
* 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) 2000,2002-2005 Silicon Graphics, Inc. All rights reserved.
*
* Routines for PCI DMA mapping. See Documentation/DMA-API.txt for
* a description of how these routines should be used.
*/
#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <asm/dma.h>
#include <asm/sn/intr.h>
#include <asm/sn/pcibus_provider_defs.h>
#include <asm/sn/pcidev.h>
#include <asm/sn/sn_sal.h>
#define SG_ENT_VIRT_ADDRESS(sg) (sg_virt((sg)))
#define SG_ENT_PHYS_ADDRESS(SG) virt_to_phys(SG_ENT_VIRT_ADDRESS(SG))
/**
* sn_dma_supported - test a DMA mask
* @dev: device to test
* @mask: DMA mask to test
*
* Return whether the given PCI device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits
* during PCI bus mastering, then you would pass 0x00ffffff as the mask to
* this function. Of course, SN only supports devices that have 32 or more
* address bits when using the PMU.
*/
static int sn_dma_supported(struct device *dev, u64 mask)
{
BUG_ON(!dev_is_pci(dev));
if (mask < 0x7fffffff)
return 0;
return 1;
}
/**
* sn_dma_set_mask - set the DMA mask
* @dev: device to set
* @dma_mask: new mask
*
* Set @dev's DMA mask if the hw supports it.
*/
int sn_dma_set_mask(struct device *dev, u64 dma_mask)
{
BUG_ON(!dev_is_pci(dev));
if (!sn_dma_supported(dev, dma_mask))
return 0;
*dev->dma_mask = dma_mask;
return 1;
}
EXPORT_SYMBOL(sn_dma_set_mask);
/**
* sn_dma_alloc_coherent - allocate memory for coherent DMA
* @dev: device to allocate for
* @size: size of the region
* @dma_handle: DMA (bus) address
* @flags: memory allocation flags
*
* dma_alloc_coherent() returns a pointer to a memory region suitable for
* coherent DMA traffic to/from a PCI device. On SN platforms, this means
* that @dma_handle will have the %PCIIO_DMA_CMD flag set.
*
* This interface is usually used for "command" streams (e.g. the command
* queue for a SCSI controller). See Documentation/DMA-API.txt for
* more information.
*/
static void *sn_dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t * dma_handle, gfp_t flags,
struct dma_attrs *attrs)
{
void *cpuaddr;
unsigned long phys_addr;
int node;
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
BUG_ON(!dev_is_pci(dev));
/*
* Allocate the memory.
*/
node = pcibus_to_node(pdev->bus);
if (likely(node >=0)) {
struct page *p = alloc_pages_exact_node(node,
flags, get_order(size));
if (likely(p))
cpuaddr = page_address(p);
else
return NULL;
} else
cpuaddr = (void *)__get_free_pages(flags, get_order(size));
if (unlikely(!cpuaddr))
return NULL;
memset(cpuaddr, 0x0, size);
/* physical addr. of the memory we just got */
phys_addr = __pa(cpuaddr);
/*
* 64 bit address translations should never fail.
* 32 bit translations can fail if there are insufficient mapping
* resources.
*/
*dma_handle = provider->dma_map_consistent(pdev, phys_addr, size,
SN_DMA_ADDR_PHYS);
if (!*dma_handle) {
printk(KERN_ERR "%s: out of ATEs\n", __func__);
free_pages((unsigned long)cpuaddr, get_order(size));
return NULL;
}
return cpuaddr;
}
/**
* sn_pci_free_coherent - free memory associated with coherent DMAable region
* @dev: device to free for
* @size: size to free
* @cpu_addr: kernel virtual address to free
* @dma_handle: DMA address associated with this region
*
* Frees the memory allocated by dma_alloc_coherent(), potentially unmapping
* any associated IOMMU mappings.
*/
static void sn_dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_handle, struct dma_attrs *attrs)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
BUG_ON(!dev_is_pci(dev));
provider->dma_unmap(pdev, dma_handle, 0);
free_pages((unsigned long)cpu_addr, get_order(size));
}
/**
* sn_dma_map_single_attrs - map a single page for DMA
* @dev: device to map for
* @cpu_addr: kernel virtual address of the region to map
* @size: size of the region
* @direction: DMA direction
* @attrs: optional dma attributes
*
* Map the region pointed to by @cpu_addr for DMA and return the
* DMA address.
*
* We map this to the one step pcibr_dmamap_trans interface rather than
* the two step pcibr_dmamap_alloc/pcibr_dmamap_addr because we have
* no way of saving the dmamap handle from the alloc to later free
* (which is pretty much unacceptable).
*
* mappings with the DMA_ATTR_WRITE_BARRIER get mapped with
* dma_map_consistent() so that writes force a flush of pending DMA.
* (See "SGI Altix Architecture Considerations for Linux Device Drivers",
* Document Number: 007-4763-001)
*
* TODO: simplify our interface;
* figure out how to save dmamap handle so can use two step.
*/
static dma_addr_t sn_dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
struct dma_attrs *attrs)
{
void *cpu_addr = page_address(page) + offset;
dma_addr_t dma_addr;
unsigned long phys_addr;
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
int dmabarr;
dmabarr = dma_get_attr(DMA_ATTR_WRITE_BARRIER, attrs);
BUG_ON(!dev_is_pci(dev));
phys_addr = __pa(cpu_addr);
if (dmabarr)
dma_addr = provider->dma_map_consistent(pdev, phys_addr,
size, SN_DMA_ADDR_PHYS);
else
dma_addr = provider->dma_map(pdev, phys_addr, size,
SN_DMA_ADDR_PHYS);
if (!dma_addr) {
printk(KERN_ERR "%s: out of ATEs\n", __func__);
return 0;
}
return dma_addr;
}
/**
* sn_dma_unmap_single_attrs - unamp a DMA mapped page
* @dev: device to sync
* @dma_addr: DMA address to sync
* @size: size of region
* @direction: DMA direction
* @attrs: optional dma attributes
*
* This routine is supposed to sync the DMA region specified
* by @dma_handle into the coherence domain. On SN, we're always cache
* coherent, so we just need to free any ATEs associated with this mapping.
*/
static void sn_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
BUG_ON(!dev_is_pci(dev));
provider->dma_unmap(pdev, dma_addr, dir);
}
/**
* sn_dma_unmap_sg - unmap a DMA scatterlist
* @dev: device to unmap
* @sg: scatterlist to unmap
* @nhwentries: number of scatterlist entries
* @direction: DMA direction
* @attrs: optional dma attributes
*
* Unmap a set of streaming mode DMA translations.
*/
static void sn_dma_unmap_sg(struct device *dev, struct scatterlist *sgl,
int nhwentries, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
int i;
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
struct scatterlist *sg;
BUG_ON(!dev_is_pci(dev));
for_each_sg(sgl, sg, nhwentries, i) {
provider->dma_unmap(pdev, sg->dma_address, dir);
sg->dma_address = (dma_addr_t) NULL;
sg->dma_length = 0;
}
}
/**
* sn_dma_map_sg - map a scatterlist for DMA
* @dev: device to map for
* @sg: scatterlist to map
* @nhwentries: number of entries
* @direction: direction of the DMA transaction
* @attrs: optional dma attributes
*
* mappings with the DMA_ATTR_WRITE_BARRIER get mapped with
* dma_map_consistent() so that writes force a flush of pending DMA.
* (See "SGI Altix Architecture Considerations for Linux Device Drivers",
* Document Number: 007-4763-001)
*
* Maps each entry of @sg for DMA.
*/
static int sn_dma_map_sg(struct device *dev, struct scatterlist *sgl,
int nhwentries, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
unsigned long phys_addr;
struct scatterlist *saved_sg = sgl, *sg;
struct pci_dev *pdev = to_pci_dev(dev);
struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
int i;
int dmabarr;
dmabarr = dma_get_attr(DMA_ATTR_WRITE_BARRIER, attrs);
BUG_ON(!dev_is_pci(dev));
/*
* Setup a DMA address for each entry in the scatterlist.
*/
for_each_sg(sgl, sg, nhwentries, i) {
dma_addr_t dma_addr;
phys_addr = SG_ENT_PHYS_ADDRESS(sg);
if (dmabarr)
dma_addr = provider->dma_map_consistent(pdev,
phys_addr,
sg->length,
SN_DMA_ADDR_PHYS);
else
dma_addr = provider->dma_map(pdev, phys_addr,
sg->length,
SN_DMA_ADDR_PHYS);
sg->dma_address = dma_addr;
if (!sg->dma_address) {
printk(KERN_ERR "%s: out of ATEs\n", __func__);
/*
* Free any successfully allocated entries.
*/
if (i > 0)
sn_dma_unmap_sg(dev, saved_sg, i, dir, attrs);
return 0;
}
sg->dma_length = sg->length;
}
return nhwentries;
}
static void sn_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction dir)
{
BUG_ON(!dev_is_pci(dev));
}
static void sn_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
size_t size,
enum dma_data_direction dir)
{
BUG_ON(!dev_is_pci(dev));
}
static void sn_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir)
{
BUG_ON(!dev_is_pci(dev));
}
static void sn_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int nelems, enum dma_data_direction dir)
{
BUG_ON(!dev_is_pci(dev));
}
static int sn_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return 0;
}
u64 sn_dma_get_required_mask(struct device *dev)
{
return DMA_BIT_MASK(64);
}
EXPORT_SYMBOL_GPL(sn_dma_get_required_mask);
char *sn_pci_get_legacy_mem(struct pci_bus *bus)
{
if (!SN_PCIBUS_BUSSOFT(bus))
return ERR_PTR(-ENODEV);
return (char *)(SN_PCIBUS_BUSSOFT(bus)->bs_legacy_mem | __IA64_UNCACHED_OFFSET);
}
int sn_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
{
unsigned long addr;
int ret;
struct ia64_sal_retval isrv;
/*
* First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
* around hw issues at the pci bus level. SGI proms older than
* 4.10 don't implement this.
*/
SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
pci_domain_nr(bus), bus->number,
0, /* io */
0, /* read */
port, size, __pa(val));
if (isrv.status == 0)
return size;
/*
* If the above failed, retry using the SAL_PROBE call which should
* be present in all proms (but which cannot work round PCI chipset
* bugs). This code is retained for compatibility with old
* pre-4.10 proms, and should be removed at some point in the future.
*/
if (!SN_PCIBUS_BUSSOFT(bus))
return -ENODEV;
addr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
addr += port;
ret = ia64_sn_probe_mem(addr, (long)size, (void *)val);
if (ret == 2)
return -EINVAL;
if (ret == 1)
*val = -1;
return size;
}
int sn_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size)
{
int ret = size;
unsigned long paddr;
unsigned long *addr;
struct ia64_sal_retval isrv;
/*
* First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work
* around hw issues at the pci bus level. SGI proms older than
* 4.10 don't implement this.
*/
SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE,
pci_domain_nr(bus), bus->number,
0, /* io */
1, /* write */
port, size, __pa(&val));
if (isrv.status == 0)
return size;
/*
* If the above failed, retry using the SAL_PROBE call which should
* be present in all proms (but which cannot work round PCI chipset
* bugs). This code is retained for compatibility with old
* pre-4.10 proms, and should be removed at some point in the future.
*/
if (!SN_PCIBUS_BUSSOFT(bus)) {
ret = -ENODEV;
goto out;
}
/* Put the phys addr in uncached space */
paddr = SN_PCIBUS_BUSSOFT(bus)->bs_legacy_io | __IA64_UNCACHED_OFFSET;
paddr += port;
addr = (unsigned long *)paddr;
switch (size) {
case 1:
*(volatile u8 *)(addr) = (u8)(val);
break;
case 2:
*(volatile u16 *)(addr) = (u16)(val);
break;
case 4:
*(volatile u32 *)(addr) = (u32)(val);
break;
default:
ret = -EINVAL;
break;
}
out:
return ret;
}
static struct dma_map_ops sn_dma_ops = {
.alloc = sn_dma_alloc_coherent,
.free = sn_dma_free_coherent,
.map_page = sn_dma_map_page,
.unmap_page = sn_dma_unmap_page,
.map_sg = sn_dma_map_sg,
.unmap_sg = sn_dma_unmap_sg,
.sync_single_for_cpu = sn_dma_sync_single_for_cpu,
.sync_sg_for_cpu = sn_dma_sync_sg_for_cpu,
.sync_single_for_device = sn_dma_sync_single_for_device,
.sync_sg_for_device = sn_dma_sync_sg_for_device,
.mapping_error = sn_dma_mapping_error,
.dma_supported = sn_dma_supported,
};
void sn_dma_init(void)
{
dma_ops = &sn_dma_ops;
}