PCI/alpha: pci sysfs resources

This closes http://bugzilla.kernel.org/show_bug.cgi?id=10893
which is a showstopper for X development on alpha.

The generic HAVE_PCI_MMAP code (drivers/pci-sysfs.c) is not
very useful since we have to deal with three different types
of MMIO address spaces: sparse and dense mappings for old
ev4/ev5 machines and "normal" 1:1 MMIO space (bwx) for ev56 and
later.
Also "write combine" mappings are meaningless on alpha - roughly
speaking, alpha does write combining, IO reordering and other
optimizations by default, unless user splits IO accesses
with memory barriers.

I think the cleanest way to deal with resource files on alpha
is to convert the default no-op pci_create_resource_files() and
pci_remove_resource_files() for !HAVE_PCI_MMAP case into __weak
functions and override them with alpha specific ones.

Another alpha hook is needed for "legacy_" resource files
to handle sparse addressing (pci_adjust_legacy_attr).

With the "standard" resourceN files on ev56/ev6 libpciaccess
works "out of the box". Handling of resourceN_sparse/resourceN_dense
files on older machines obviously requires some userland work.

Sparse/dense stuff has been tested on sx164 (pca56/pyxis, normally
uses bwx IO) with the kernel hacked into "cia compatible" mode.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Ivan Kokshaysky 2009-02-17 13:46:53 +03:00 committed by Jesse Barnes
parent ea7415512a
commit 10a0ef39fb
4 changed files with 398 additions and 3 deletions

View file

@ -273,4 +273,18 @@ struct pci_dev *alpha_gendev_to_pci(struct device *dev);
extern struct pci_dev *isa_bridge;
extern int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val,
size_t count);
extern int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val,
size_t count);
extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
struct vm_area_struct *vma,
enum pci_mmap_state mmap_state);
extern void pci_adjust_legacy_attr(struct pci_bus *bus,
enum pci_mmap_state mmap_type);
#define HAVE_PCI_LEGACY 1
extern int pci_create_resource_files(struct pci_dev *dev);
extern void pci_remove_resource_files(struct pci_dev *dev);
#endif /* __ALPHA_PCI_H */

View file

@ -12,7 +12,7 @@ obj-y := entry.o traps.o process.o init_task.o osf_sys.o irq.o \
obj-$(CONFIG_VGA_HOSE) += console.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_PCI) += pci.o pci_iommu.o
obj-$(CONFIG_PCI) += pci.o pci_iommu.o pci-sysfs.o
obj-$(CONFIG_SRM_ENV) += srm_env.o
obj-$(CONFIG_MODULES) += module.o

View file

@ -0,0 +1,366 @@
/*
* arch/alpha/kernel/pci-sysfs.c
*
* Copyright (C) 2009 Ivan Kokshaysky
*
* Alpha PCI resource files.
*
* Loosely based on generic HAVE_PCI_MMAP implementation in
* drivers/pci/pci-sysfs.c
*/
#include <linux/sched.h>
#include <linux/pci.h>
static int hose_mmap_page_range(struct pci_controller *hose,
struct vm_area_struct *vma,
enum pci_mmap_state mmap_type, int sparse)
{
unsigned long base;
if (mmap_type == pci_mmap_mem)
base = sparse ? hose->sparse_mem_base : hose->dense_mem_base;
else
base = sparse ? hose->sparse_io_base : hose->dense_io_base;
vma->vm_pgoff += base >> PAGE_SHIFT;
vma->vm_flags |= (VM_IO | VM_RESERVED);
return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
vma->vm_end - vma->vm_start,
vma->vm_page_prot);
}
static int __pci_mmap_fits(struct pci_dev *pdev, int num,
struct vm_area_struct *vma, int sparse)
{
unsigned long nr, start, size;
int shift = sparse ? 5 : 0;
nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
start = vma->vm_pgoff;
size = ((pci_resource_len(pdev, num) - 1) >> (PAGE_SHIFT - shift)) + 1;
if (start < size && size - start >= nr)
return 1;
WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on %s BAR %d "
"(size 0x%08lx)\n",
current->comm, sparse ? " sparse" : "", start, start + nr,
pci_name(pdev), num, size);
return 0;
}
/**
* pci_mmap_resource - map a PCI resource into user memory space
* @kobj: kobject for mapping
* @attr: struct bin_attribute for the file being mapped
* @vma: struct vm_area_struct passed into the mmap
* @sparse: address space type
*
* Use the bus mapping routines to map a PCI resource into userspace.
*/
static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
struct vm_area_struct *vma, int sparse)
{
struct pci_dev *pdev = to_pci_dev(container_of(kobj,
struct device, kobj));
struct resource *res = (struct resource *)attr->private;
enum pci_mmap_state mmap_type;
struct pci_bus_region bar;
int i;
for (i = 0; i < PCI_ROM_RESOURCE; i++)
if (res == &pdev->resource[i])
break;
if (i >= PCI_ROM_RESOURCE)
return -ENODEV;
if (!__pci_mmap_fits(pdev, i, vma, sparse))
return -EINVAL;
if (iomem_is_exclusive(res->start))
return -EINVAL;
pcibios_resource_to_bus(pdev, &bar, res);
vma->vm_pgoff += bar.start >> (PAGE_SHIFT - (sparse ? 5 : 0));
mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
return hose_mmap_page_range(pdev->sysdata, vma, mmap_type, sparse);
}
static int pci_mmap_resource_sparse(struct kobject *kobj,
struct bin_attribute *attr,
struct vm_area_struct *vma)
{
return pci_mmap_resource(kobj, attr, vma, 1);
}
static int pci_mmap_resource_dense(struct kobject *kobj,
struct bin_attribute *attr,
struct vm_area_struct *vma)
{
return pci_mmap_resource(kobj, attr, vma, 0);
}
/**
* pci_remove_resource_files - cleanup resource files
* @dev: dev to cleanup
*
* If we created resource files for @dev, remove them from sysfs and
* free their resources.
*/
void pci_remove_resource_files(struct pci_dev *pdev)
{
int i;
for (i = 0; i < PCI_ROM_RESOURCE; i++) {
struct bin_attribute *res_attr;
res_attr = pdev->res_attr[i];
if (res_attr) {
sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
kfree(res_attr);
}
res_attr = pdev->res_attr_wc[i];
if (res_attr) {
sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
kfree(res_attr);
}
}
}
static int sparse_mem_mmap_fits(struct pci_dev *pdev, int num)
{
struct pci_bus_region bar;
struct pci_controller *hose = pdev->sysdata;
long dense_offset;
unsigned long sparse_size;
pcibios_resource_to_bus(pdev, &bar, &pdev->resource[num]);
/* All core logic chips have 4G sparse address space, except
CIA which has 16G (see xxx_SPARSE_MEM and xxx_DENSE_MEM
definitions in asm/core_xxx.h files). This corresponds
to 128M or 512M of the bus space. */
dense_offset = (long)(hose->dense_mem_base - hose->sparse_mem_base);
sparse_size = dense_offset >= 0x400000000UL ? 0x20000000 : 0x8000000;
return bar.end < sparse_size;
}
static int pci_create_one_attr(struct pci_dev *pdev, int num, char *name,
char *suffix, struct bin_attribute *res_attr,
unsigned long sparse)
{
size_t size = pci_resource_len(pdev, num);
sprintf(name, "resource%d%s", num, suffix);
res_attr->mmap = sparse ? pci_mmap_resource_sparse :
pci_mmap_resource_dense;
res_attr->attr.name = name;
res_attr->attr.mode = S_IRUSR | S_IWUSR;
res_attr->size = sparse ? size << 5 : size;
res_attr->private = &pdev->resource[num];
return sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
}
static int pci_create_attr(struct pci_dev *pdev, int num)
{
/* allocate attribute structure, piggyback attribute name */
int retval, nlen1, nlen2 = 0, res_count = 1;
unsigned long sparse_base, dense_base;
struct bin_attribute *attr;
struct pci_controller *hose = pdev->sysdata;
char *suffix, *attr_name;
suffix = ""; /* Assume bwx machine, normal resourceN files. */
nlen1 = 10;
if (pdev->resource[num].flags & IORESOURCE_MEM) {
sparse_base = hose->sparse_mem_base;
dense_base = hose->dense_mem_base;
if (sparse_base && !sparse_mem_mmap_fits(pdev, num)) {
sparse_base = 0;
suffix = "_dense";
nlen1 = 16; /* resourceN_dense */
}
} else {
sparse_base = hose->sparse_io_base;
dense_base = hose->dense_io_base;
}
if (sparse_base) {
suffix = "_sparse";
nlen1 = 17;
if (dense_base) {
nlen2 = 16; /* resourceN_dense */
res_count = 2;
}
}
attr = kzalloc(sizeof(*attr) * res_count + nlen1 + nlen2, GFP_ATOMIC);
if (!attr)
return -ENOMEM;
/* Create bwx, sparse or single dense file */
attr_name = (char *)(attr + res_count);
pdev->res_attr[num] = attr;
retval = pci_create_one_attr(pdev, num, attr_name, suffix, attr,
sparse_base);
if (retval || res_count == 1)
return retval;
/* Create dense file */
attr_name += nlen1;
attr++;
pdev->res_attr_wc[num] = attr;
return pci_create_one_attr(pdev, num, attr_name, "_dense", attr, 0);
}
/**
* pci_create_resource_files - create resource files in sysfs for @dev
* @dev: dev in question
*
* Walk the resources in @dev creating files for each resource available.
*/
int pci_create_resource_files(struct pci_dev *pdev)
{
int i;
int retval;
/* Expose the PCI resources from this device as files */
for (i = 0; i < PCI_ROM_RESOURCE; i++) {
/* skip empty resources */
if (!pci_resource_len(pdev, i))
continue;
retval = pci_create_attr(pdev, i);
if (retval) {
pci_remove_resource_files(pdev);
return retval;
}
}
return 0;
}
/* Legacy I/O bus mapping stuff. */
static int __legacy_mmap_fits(struct pci_controller *hose,
struct vm_area_struct *vma,
unsigned long res_size, int sparse)
{
unsigned long nr, start, size;
nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
start = vma->vm_pgoff;
size = ((res_size - 1) >> PAGE_SHIFT) + 1;
if (start < size && size - start >= nr)
return 1;
WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on hose %d "
"(size 0x%08lx)\n",
current->comm, sparse ? " sparse" : "", start, start + nr,
hose->index, size);
return 0;
}
static inline int has_sparse(struct pci_controller *hose,
enum pci_mmap_state mmap_type)
{
unsigned long base;
base = (mmap_type == pci_mmap_mem) ? hose->sparse_mem_base :
hose->sparse_io_base;
return base != 0;
}
int pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
enum pci_mmap_state mmap_type)
{
struct pci_controller *hose = bus->sysdata;
int sparse = has_sparse(hose, mmap_type);
unsigned long res_size;
res_size = (mmap_type == pci_mmap_mem) ? bus->legacy_mem->size :
bus->legacy_io->size;
if (!__legacy_mmap_fits(hose, vma, res_size, sparse))
return -EINVAL;
return hose_mmap_page_range(hose, vma, mmap_type, sparse);
}
/**
* pci_adjust_legacy_attr - adjustment of legacy file attributes
* @b: bus to create files under
* @mmap_type: I/O port or memory
*
* Adjust file name and size for sparse mappings.
*/
void pci_adjust_legacy_attr(struct pci_bus *bus, enum pci_mmap_state mmap_type)
{
struct pci_controller *hose = bus->sysdata;
if (!has_sparse(hose, mmap_type))
return;
if (mmap_type == pci_mmap_mem) {
bus->legacy_mem->attr.name = "legacy_mem_sparse";
bus->legacy_mem->size <<= 5;
} else {
bus->legacy_io->attr.name = "legacy_io_sparse";
bus->legacy_io->size <<= 5;
}
return;
}
/* Legacy I/O bus read/write functions */
int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
{
struct pci_controller *hose = bus->sysdata;
port += hose->io_space->start;
switch(size) {
case 1:
*((u8 *)val) = inb(port);
return 1;
case 2:
if (port & 1)
return -EINVAL;
*((u16 *)val) = inw(port);
return 2;
case 4:
if (port & 3)
return -EINVAL;
*((u32 *)val) = inl(port);
return 4;
}
return -EINVAL;
}
int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
{
struct pci_controller *hose = bus->sysdata;
port += hose->io_space->start;
switch(size) {
case 1:
outb(port, val);
return 1;
case 2:
if (port & 1)
return -EINVAL;
outw(port, val);
return 2;
case 4:
if (port & 3)
return -EINVAL;
outl(port, val);
return 4;
}
return -EINVAL;
}

View file

@ -492,6 +492,19 @@ pci_mmap_legacy_io(struct kobject *kobj, struct bin_attribute *attr,
return pci_mmap_legacy_page_range(bus, vma, pci_mmap_io);
}
/**
* pci_adjust_legacy_attr - adjustment of legacy file attributes
* @b: bus to create files under
* @mmap_type: I/O port or memory
*
* Stub implementation. Can be overridden by arch if necessary.
*/
void __weak
pci_adjust_legacy_attr(struct pci_bus *b, enum pci_mmap_state mmap_type)
{
return;
}
/**
* pci_create_legacy_files - create legacy I/O port and memory files
* @b: bus to create files under
@ -518,6 +531,7 @@ void pci_create_legacy_files(struct pci_bus *b)
b->legacy_io->read = pci_read_legacy_io;
b->legacy_io->write = pci_write_legacy_io;
b->legacy_io->mmap = pci_mmap_legacy_io;
pci_adjust_legacy_attr(b, pci_mmap_io);
error = device_create_bin_file(&b->dev, b->legacy_io);
if (error)
goto legacy_io_err;
@ -528,6 +542,7 @@ void pci_create_legacy_files(struct pci_bus *b)
b->legacy_mem->size = 1024*1024;
b->legacy_mem->attr.mode = S_IRUSR | S_IWUSR;
b->legacy_mem->mmap = pci_mmap_legacy_mem;
pci_adjust_legacy_attr(b, pci_mmap_mem);
error = device_create_bin_file(&b->dev, b->legacy_mem);
if (error)
goto legacy_mem_err;
@ -719,8 +734,8 @@ static int pci_create_resource_files(struct pci_dev *pdev)
return 0;
}
#else /* !HAVE_PCI_MMAP */
static inline int pci_create_resource_files(struct pci_dev *dev) { return 0; }
static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
int __weak pci_create_resource_files(struct pci_dev *dev) { return 0; }
void __weak pci_remove_resource_files(struct pci_dev *dev) { return; }
#endif /* HAVE_PCI_MMAP */
/**