From e9f82cb75096ae30658a72d473bf170bf4d3bb2e Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 14 Oct 2008 11:55:31 +1100 Subject: [PATCH] powerpc/PCI: Add legacy PCI access via sysfs This patch adds support for legacy_io and legacy_mem files in bus class directories in sysfs for powerpc Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Jesse Barnes --- arch/powerpc/include/asm/pci-bridge.h | 7 ++ arch/powerpc/include/asm/pci.h | 11 +++ arch/powerpc/kernel/pci-common.c | 136 +++++++++++++++++++++++++- 3 files changed, 153 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h index ae2ea803a0f..9047af7baa6 100644 --- a/arch/powerpc/include/asm/pci-bridge.h +++ b/arch/powerpc/include/asm/pci-bridge.h @@ -74,6 +74,13 @@ struct pci_controller { unsigned long pci_io_size; #endif + /* Some machines have a special region to forward the ISA + * "memory" cycles such as VGA memory regions. Left to 0 + * if unsupported + */ + resource_size_t isa_mem_phys; + resource_size_t isa_mem_size; + struct pci_ops *ops; unsigned int __iomem *cfg_addr; void __iomem *cfg_data; diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h index 0e52c7828ea..39d547fde95 100644 --- a/arch/powerpc/include/asm/pci.h +++ b/arch/powerpc/include/asm/pci.h @@ -123,6 +123,16 @@ int pci_mmap_page_range(struct pci_dev *pdev, struct vm_area_struct *vma, /* Tell drivers/pci/proc.c that we have pci_mmap_page_range() */ #define HAVE_PCI_MMAP 1 +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); + +#define HAVE_PCI_LEGACY 1 + #if defined(CONFIG_PPC64) || defined(CONFIG_NOT_COHERENT_CACHE) /* * For 64-bit kernels, pci_unmap_{single,page} is not a nop. @@ -226,5 +236,6 @@ extern void pci_resource_to_user(const struct pci_dev *dev, int bar, extern void pcibios_do_bus_setup(struct pci_bus *bus); extern void pcibios_fixup_of_probed_bus(struct pci_bus *bus); + #endif /* __KERNEL__ */ #endif /* __ASM_POWERPC_PCI_H */ diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 01ce8c38bae..3815d84a1ef 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -451,7 +451,8 @@ pgprot_t pci_phys_mem_access_prot(struct file *file, pci_dev_put(pdev); } - DBG("non-PCI map for %lx, prot: %lx\n", offset, prot); + DBG("non-PCI map for %llx, prot: %lx\n", + (unsigned long long)offset, prot); return __pgprot(prot); } @@ -490,6 +491,131 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, return ret; } +/* This provides legacy IO read access on a bus */ +int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size) +{ + unsigned long offset; + struct pci_controller *hose = pci_bus_to_host(bus); + struct resource *rp = &hose->io_resource; + void __iomem *addr; + + /* Check if port can be supported by that bus. We only check + * the ranges of the PHB though, not the bus itself as the rules + * for forwarding legacy cycles down bridges are not our problem + * here. So if the host bridge supports it, we do it. + */ + offset = (unsigned long)hose->io_base_virt - _IO_BASE; + offset += port; + + if (!(rp->flags & IORESOURCE_IO)) + return -ENXIO; + if (offset < rp->start || (offset + size) > rp->end) + return -ENXIO; + addr = hose->io_base_virt + port; + + switch(size) { + case 1: + *((u8 *)val) = in_8(addr); + return 1; + case 2: + if (port & 1) + return -EINVAL; + *((u16 *)val) = in_le16(addr); + return 2; + case 4: + if (port & 3) + return -EINVAL; + *((u32 *)val) = in_le32(addr); + return 4; + } + return -EINVAL; +} + +/* This provides legacy IO write access on a bus */ +int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size) +{ + unsigned long offset; + struct pci_controller *hose = pci_bus_to_host(bus); + struct resource *rp = &hose->io_resource; + void __iomem *addr; + + /* Check if port can be supported by that bus. We only check + * the ranges of the PHB though, not the bus itself as the rules + * for forwarding legacy cycles down bridges are not our problem + * here. So if the host bridge supports it, we do it. + */ + offset = (unsigned long)hose->io_base_virt - _IO_BASE; + offset += port; + + if (!(rp->flags & IORESOURCE_IO)) + return -ENXIO; + if (offset < rp->start || (offset + size) > rp->end) + return -ENXIO; + addr = hose->io_base_virt + port; + + /* WARNING: The generic code is idiotic. It gets passed a pointer + * to what can be a 1, 2 or 4 byte quantity and always reads that + * as a u32, which means that we have to correct the location of + * the data read within those 32 bits for size 1 and 2 + */ + switch(size) { + case 1: + out_8(addr, val >> 24); + return 1; + case 2: + if (port & 1) + return -EINVAL; + out_le16(addr, val >> 16); + return 2; + case 4: + if (port & 3) + return -EINVAL; + out_le32(addr, val); + return 4; + } + return -EINVAL; +} + +/* This provides legacy IO or memory mmap access on a bus */ +int pci_mmap_legacy_page_range(struct pci_bus *bus, + struct vm_area_struct *vma, + enum pci_mmap_state mmap_state) +{ + struct pci_controller *hose = pci_bus_to_host(bus); + resource_size_t offset = + ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT; + resource_size_t size = vma->vm_end - vma->vm_start; + struct resource *rp; + + pr_debug("pci_mmap_legacy_page_range(%04x:%02x, %s @%llx..%llx)\n", + pci_domain_nr(bus), bus->number, + mmap_state == pci_mmap_mem ? "MEM" : "IO", + (unsigned long long)offset, + (unsigned long long)(offset + size - 1)); + + if (mmap_state == pci_mmap_mem) { + if ((offset + size) > hose->isa_mem_size) + return -ENXIO; + offset += hose->isa_mem_phys; + } else { + unsigned long io_offset = (unsigned long)hose->io_base_virt - _IO_BASE; + unsigned long roffset = offset + io_offset; + rp = &hose->io_resource; + if (!(rp->flags & IORESOURCE_IO)) + return -ENXIO; + if (roffset < rp->start || (roffset + size) > rp->end) + return -ENXIO; + offset += hose->io_base_phys; + } + pr_debug(" -> mapping phys %llx\n", (unsigned long long)offset); + + vma->vm_pgoff = offset >> PAGE_SHIFT; + vma->vm_page_prot |= _PAGE_NO_CACHE | _PAGE_GUARDED; + return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, + vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + void pci_resource_to_user(const struct pci_dev *dev, int bar, const struct resource *rsrc, resource_size_t *start, resource_size_t *end) @@ -592,6 +718,12 @@ void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose, cpu_addr = of_translate_address(dev, ranges + 3); size = of_read_number(ranges + pna + 3, 2); ranges += np; + + /* If we failed translation or got a zero-sized region + * (some FW try to feed us with non sensical zero sized regions + * such as power3 which look like some kind of attempt at exposing + * the VGA memory hole) + */ if (cpu_addr == OF_BAD_ADDR || size == 0) continue; @@ -665,6 +797,8 @@ void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose, isa_hole = memno; if (primary || isa_mem_base == 0) isa_mem_base = cpu_addr; + hose->isa_mem_phys = cpu_addr; + hose->isa_mem_size = size; } /* We get the PCI/Mem offset from the first range or -- 2.41.0