From 10a0ef39fbd1d484c2bbc1ffd83d57ecef209140 Mon Sep 17 00:00:00 2001 From: Ivan Kokshaysky Date: Tue, 17 Feb 2009 13:46:53 +0300 Subject: 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 Signed-off-by: Jesse Barnes --- arch/alpha/kernel/Makefile | 2 +- arch/alpha/kernel/pci-sysfs.c | 366 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 367 insertions(+), 1 deletion(-) create mode 100644 arch/alpha/kernel/pci-sysfs.c (limited to 'arch/alpha/kernel') diff --git a/arch/alpha/kernel/Makefile b/arch/alpha/kernel/Makefile index b469775..a427538 100644 --- a/arch/alpha/kernel/Makefile +++ b/arch/alpha/kernel/Makefile @@ -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 diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c new file mode 100644 index 0000000..6ea822e --- /dev/null +++ b/arch/alpha/kernel/pci-sysfs.c @@ -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 +#include + +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; +} -- cgit v1.1