/* * ioport.c: Simple io mapping allocator. * * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx) * * 1996: sparc_free_io, 1999: ioremap()/iounmap() by Pete Zaitcev. * * 2000/01/29 * <rth> zait: as long as pci_alloc_consistent produces something addressable, * things are ok. * <zaitcev> rth: no, it is relevant, because get_free_pages returns you a * pointer into the big page mapping * <rth> zait: so what? * <rth> zait: remap_it_my_way(virt_to_phys(get_free_page())) * <zaitcev> Hmm * <zaitcev> Suppose I did this remap_it_my_way(virt_to_phys(get_free_page())). * So far so good. * <zaitcev> Now, driver calls pci_free_consistent(with result of * remap_it_my_way()). * <zaitcev> How do you find the address to pass to free_pages()? * <rth> zait: walk the page tables? It's only two or three level after all. * <rth> zait: you have to walk them anyway to remove the mapping. * <zaitcev> Hmm * <zaitcev> Sounds reasonable */ #include <linux/module.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/ioport.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/pci.h> /* struct pci_dev */ #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/scatterlist.h> #include <linux/of_device.h> #include <asm/io.h> #include <asm/vaddrs.h> #include <asm/oplib.h> #include <asm/prom.h> #include <asm/page.h> #include <asm/pgalloc.h> #include <asm/dma.h> #include <asm/iommu.h> #include <asm/io-unit.h> #include <asm/leon.h> /* This function must make sure that caches and memory are coherent after DMA * On LEON systems without cache snooping it flushes the entire D-CACHE. */ #ifndef CONFIG_SPARC_LEON static inline void dma_make_coherent(unsigned long pa, unsigned long len) { } #else static inline void dma_make_coherent(unsigned long pa, unsigned long len) { if (!sparc_leon3_snooping_enabled()) leon_flush_dcache_all(); } #endif static void __iomem *_sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz); static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys, unsigned long size, char *name); static void _sparc_free_io(struct resource *res); static void register_proc_sparc_ioport(void); /* This points to the next to use virtual memory for DVMA mappings */ static struct resource _sparc_dvma = { .name = "sparc_dvma", .start = DVMA_VADDR, .end = DVMA_END - 1 }; /* This points to the start of I/O mappings, cluable from outside. */ /*ext*/ struct resource sparc_iomap = { .name = "sparc_iomap", .start = IOBASE_VADDR, .end = IOBASE_END - 1 }; /* * Our mini-allocator... * Boy this is gross! We need it because we must map I/O for * timers and interrupt controller before the kmalloc is available. */ #define XNMLN 15 #define XNRES 10 /* SS-10 uses 8 */ struct xresource { struct resource xres; /* Must be first */ int xflag; /* 1 == used */ char xname[XNMLN+1]; }; static struct xresource xresv[XNRES]; static struct xresource *xres_alloc(void) { struct xresource *xrp; int n; xrp = xresv; for (n = 0; n < XNRES; n++) { if (xrp->xflag == 0) { xrp->xflag = 1; return xrp; } xrp++; } return NULL; } static void xres_free(struct xresource *xrp) { xrp->xflag = 0; } /* * These are typically used in PCI drivers * which are trying to be cross-platform. * * Bus type is always zero on IIep. */ void __iomem *ioremap(unsigned long offset, unsigned long size) { char name[14]; sprintf(name, "phys_%08x", (u32)offset); return _sparc_alloc_io(0, offset, size, name); } EXPORT_SYMBOL(ioremap); /* * Comlimentary to ioremap(). */ void iounmap(volatile void __iomem *virtual) { unsigned long vaddr = (unsigned long) virtual & PAGE_MASK; struct resource *res; /* * XXX Too slow. Can have 8192 DVMA pages on sun4m in the worst case. * This probably warrants some sort of hashing. */ if ((res = lookup_resource(&sparc_iomap, vaddr)) == NULL) { printk("free_io/iounmap: cannot free %lx\n", vaddr); return; } _sparc_free_io(res); if ((char *)res >= (char*)xresv && (char *)res < (char *)&xresv[XNRES]) { xres_free((struct xresource *)res); } else { kfree(res); } } EXPORT_SYMBOL(iounmap); void __iomem *of_ioremap(struct resource *res, unsigned long offset, unsigned long size, char *name) { return _sparc_alloc_io(res->flags & 0xF, res->start + offset, size, name); } EXPORT_SYMBOL(of_ioremap); void of_iounmap(struct resource *res, void __iomem *base, unsigned long size) { iounmap(base); } EXPORT_SYMBOL(of_iounmap); /* * Meat of mapping */ static void __iomem *_sparc_alloc_io(unsigned int busno, unsigned long phys, unsigned long size, char *name) { static int printed_full; struct xresource *xres; struct resource *res; char *tack; int tlen; void __iomem *va; /* P3 diag */ if (name == NULL) name = "???"; if ((xres = xres_alloc()) != 0) { tack = xres->xname; res = &xres->xres; } else { if (!printed_full) { printk("ioremap: done with statics, switching to malloc\n"); printed_full = 1; } tlen = strlen(name); tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL); if (tack == NULL) return NULL; memset(tack, 0, sizeof(struct resource)); res = (struct resource *) tack; tack += sizeof (struct resource); } strlcpy(tack, name, XNMLN+1); res->name = tack; va = _sparc_ioremap(res, busno, phys, size); /* printk("ioremap(0x%x:%08lx[0x%lx])=%p\n", busno, phys, size, va); */ /* P3 diag */ return va; } /* */ static void __iomem * _sparc_ioremap(struct resource *res, u32 bus, u32 pa, int sz) { unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK); if (allocate_resource(&sparc_iomap, res, (offset + sz + PAGE_SIZE-1) & PAGE_MASK, sparc_iomap.start, sparc_iomap.end, PAGE_SIZE, NULL, NULL) != 0) { /* Usually we cannot see printks in this case. */ prom_printf("alloc_io_res(%s): cannot occupy\n", (res->name != NULL)? res->name: "???"); prom_halt(); } pa &= PAGE_MASK; srmmu_mapiorange(bus, pa, res->start, resource_size(res)); return (void __iomem *)(unsigned long)(res->start + offset); } /* * Comlimentary to _sparc_ioremap(). */ static void _sparc_free_io(struct resource *res) { unsigned long plen; plen = resource_size(res); BUG_ON((plen & (PAGE_SIZE-1)) != 0); srmmu_unmapiorange(res->start, plen); release_resource(res); } #ifdef CONFIG_SBUS void sbus_set_sbus64(struct device *dev, int x) { printk("sbus_set_sbus64: unsupported\n"); } EXPORT_SYMBOL(sbus_set_sbus64); /* * Allocate a chunk of memory suitable for DMA. * Typically devices use them for control blocks. * CPU may access them without any explicit flushing. */ static void *sbus_alloc_coherent(struct device *dev, size_t len, dma_addr_t *dma_addrp, gfp_t gfp, struct dma_attrs *attrs) { struct platform_device *op = to_platform_device(dev); unsigned long len_total = PAGE_ALIGN(len); unsigned long va; struct resource *res; int order; /* XXX why are some lengths signed, others unsigned? */ if (len <= 0) { return NULL; } /* XXX So what is maxphys for us and how do drivers know it? */ if (len > 256*1024) { /* __get_free_pages() limit */ return NULL; } order = get_order(len_total); if ((va = __get_free_pages(GFP_KERNEL|__GFP_COMP, order)) == 0) goto err_nopages; if ((res = kzalloc(sizeof(struct resource), GFP_KERNEL)) == NULL) goto err_nomem; if (allocate_resource(&_sparc_dvma, res, len_total, _sparc_dvma.start, _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) { printk("sbus_alloc_consistent: cannot occupy 0x%lx", len_total); goto err_nova; } // XXX The mmu_map_dma_area does this for us below, see comments. // srmmu_mapiorange(0, virt_to_phys(va), res->start, len_total); /* * XXX That's where sdev would be used. Currently we load * all iommu tables with the same translations. */ if (mmu_map_dma_area(dev, dma_addrp, va, res->start, len_total) != 0) goto err_noiommu; res->name = op->dev.of_node->name; return (void *)(unsigned long)res->start; err_noiommu: release_resource(res); err_nova: kfree(res); err_nomem: free_pages(va, order); err_nopages: return NULL; } static void sbus_free_coherent(struct device *dev, size_t n, void *p, dma_addr_t ba, struct dma_attrs *attrs) { struct resource *res; struct page *pgv; if ((res = lookup_resource(&_sparc_dvma, (unsigned long)p)) == NULL) { printk("sbus_free_consistent: cannot free %p\n", p); return; } if (((unsigned long)p & (PAGE_SIZE-1)) != 0) { printk("sbus_free_consistent: unaligned va %p\n", p); return; } n = PAGE_ALIGN(n); if (resource_size(res) != n) { printk("sbus_free_consistent: region 0x%lx asked 0x%zx\n", (long)resource_size(res), n); return; } release_resource(res); kfree(res); pgv = virt_to_page(p); mmu_unmap_dma_area(dev, ba, n); __free_pages(pgv, get_order(n)); } /* * Map a chunk of memory so that devices can see it. * CPU view of this memory may be inconsistent with * a device view and explicit flushing is necessary. */ static dma_addr_t sbus_map_page(struct device *dev, struct page *page, unsigned long offset, size_t len, enum dma_data_direction dir, struct dma_attrs *attrs) { void *va = page_address(page) + offset; /* XXX why are some lengths signed, others unsigned? */ if (len <= 0) { return 0; } /* XXX So what is maxphys for us and how do drivers know it? */ if (len > 256*1024) { /* __get_free_pages() limit */ return 0; } return mmu_get_scsi_one(dev, va, len); } static void sbus_unmap_page(struct device *dev, dma_addr_t ba, size_t n, enum dma_data_direction dir, struct dma_attrs *attrs) { mmu_release_scsi_one(dev, ba, n); } static int sbus_map_sg(struct device *dev, struct scatterlist *sg, int n, enum dma_data_direction dir, struct dma_attrs *attrs) { mmu_get_scsi_sgl(dev, sg, n); return n; } static void sbus_unmap_sg(struct device *dev, struct scatterlist *sg, int n, enum dma_data_direction dir, struct dma_attrs *attrs) { mmu_release_scsi_sgl(dev, sg, n); } static void sbus_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int n, enum dma_data_direction dir) { BUG(); } static void sbus_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int n, enum dma_data_direction dir) { BUG(); } struct dma_map_ops sbus_dma_ops = { .alloc = sbus_alloc_coherent, .free = sbus_free_coherent, .map_page = sbus_map_page, .unmap_page = sbus_unmap_page, .map_sg = sbus_map_sg, .unmap_sg = sbus_unmap_sg, .sync_sg_for_cpu = sbus_sync_sg_for_cpu, .sync_sg_for_device = sbus_sync_sg_for_device, }; static int __init sparc_register_ioport(void) { register_proc_sparc_ioport(); return 0; } arch_initcall(sparc_register_ioport); #endif /* CONFIG_SBUS */ /* LEON reuses PCI DMA ops */ #if defined(CONFIG_PCI) || defined(CONFIG_SPARC_LEON) /* Allocate and map kernel buffer using consistent mode DMA for a device. * hwdev should be valid struct pci_dev pointer for PCI devices. */ static void *pci32_alloc_coherent(struct device *dev, size_t len, dma_addr_t *pba, gfp_t gfp, struct dma_attrs *attrs) { unsigned long len_total = PAGE_ALIGN(len); void *va; struct resource *res; int order; if (len == 0) { return NULL; } if (len > 256*1024) { /* __get_free_pages() limit */ return NULL; } order = get_order(len_total); va = (void *) __get_free_pages(GFP_KERNEL, order); if (va == NULL) { printk("pci_alloc_consistent: no %ld pages\n", len_total>>PAGE_SHIFT); goto err_nopages; } if ((res = kzalloc(sizeof(struct resource), GFP_KERNEL)) == NULL) { printk("pci_alloc_consistent: no core\n"); goto err_nomem; } if (allocate_resource(&_sparc_dvma, res, len_total, _sparc_dvma.start, _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) { printk("pci_alloc_consistent: cannot occupy 0x%lx", len_total); goto err_nova; } srmmu_mapiorange(0, virt_to_phys(va), res->start, len_total); *pba = virt_to_phys(va); /* equals virt_to_bus (R.I.P.) for us. */ return (void *) res->start; err_nova: kfree(res); err_nomem: free_pages((unsigned long)va, order); err_nopages: return NULL; } /* Free and unmap a consistent DMA buffer. * cpu_addr is what was returned from pci_alloc_consistent, * size must be the same as what as passed into pci_alloc_consistent, * and likewise dma_addr must be the same as what *dma_addrp was set to. * * References to the memory and mappings associated with cpu_addr/dma_addr * past this call are illegal. */ static void pci32_free_coherent(struct device *dev, size_t n, void *p, dma_addr_t ba, struct dma_attrs *attrs) { struct resource *res; if ((res = lookup_resource(&_sparc_dvma, (unsigned long)p)) == NULL) { printk("pci_free_consistent: cannot free %p\n", p); return; } if (((unsigned long)p & (PAGE_SIZE-1)) != 0) { printk("pci_free_consistent: unaligned va %p\n", p); return; } n = PAGE_ALIGN(n); if (resource_size(res) != n) { printk("pci_free_consistent: region 0x%lx asked 0x%lx\n", (long)resource_size(res), (long)n); return; } dma_make_coherent(ba, n); srmmu_unmapiorange((unsigned long)p, n); release_resource(res); kfree(res); free_pages((unsigned long)phys_to_virt(ba), get_order(n)); } /* * Same as pci_map_single, but with pages. */ static dma_addr_t pci32_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, struct dma_attrs *attrs) { /* IIep is write-through, not flushing. */ return page_to_phys(page) + offset; } static void pci32_unmap_page(struct device *dev, dma_addr_t ba, size_t size, enum dma_data_direction dir, struct dma_attrs *attrs) { if (dir != PCI_DMA_TODEVICE) dma_make_coherent(ba, PAGE_ALIGN(size)); } /* Map a set of buffers described by scatterlist in streaming * mode for DMA. This is the scather-gather version of the * above pci_map_single interface. Here the scatter gather list * elements are each tagged with the appropriate dma address * and length. They are obtained via sg_dma_{address,length}(SG). * * NOTE: An implementation may be able to use a smaller number of * DMA address/length pairs than there are SG table elements. * (for example via virtual mapping capabilities) * The routine returns the number of addr/length pairs actually * used, at most nents. * * Device ownership issues as mentioned above for pci_map_single are * the same here. */ static int pci32_map_sg(struct device *device, struct scatterlist *sgl, int nents, enum dma_data_direction dir, struct dma_attrs *attrs) { struct scatterlist *sg; int n; /* IIep is write-through, not flushing. */ for_each_sg(sgl, sg, nents, n) { sg->dma_address = sg_phys(sg); sg->dma_length = sg->length; } return nents; } /* Unmap a set of streaming mode DMA translations. * Again, cpu read rules concerning calls here are the same as for * pci_unmap_single() above. */ static void pci32_unmap_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, struct dma_attrs *attrs) { struct scatterlist *sg; int n; if (dir != PCI_DMA_TODEVICE) { for_each_sg(sgl, sg, nents, n) { dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length)); } } } /* Make physical memory consistent for a single * streaming mode DMA translation before or after a transfer. * * If you perform a pci_map_single() but wish to interrogate the * buffer using the cpu, yet do not wish to teardown the PCI dma * mapping, you must call this function before doing so. At the * next point you give the PCI dma address back to the card, you * must first perform a pci_dma_sync_for_device, and then the * device again owns the buffer. */ static void pci32_sync_single_for_cpu(struct device *dev, dma_addr_t ba, size_t size, enum dma_data_direction dir) { if (dir != PCI_DMA_TODEVICE) { dma_make_coherent(ba, PAGE_ALIGN(size)); } } static void pci32_sync_single_for_device(struct device *dev, dma_addr_t ba, size_t size, enum dma_data_direction dir) { if (dir != PCI_DMA_TODEVICE) { dma_make_coherent(ba, PAGE_ALIGN(size)); } } /* Make physical memory consistent for a set of streaming * mode DMA translations after a transfer. * * The same as pci_dma_sync_single_* but for a scatter-gather list, * same rules and usage. */ static void pci32_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir) { struct scatterlist *sg; int n; if (dir != PCI_DMA_TODEVICE) { for_each_sg(sgl, sg, nents, n) { dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length)); } } } static void pci32_sync_sg_for_device(struct device *device, struct scatterlist *sgl, int nents, enum dma_data_direction dir) { struct scatterlist *sg; int n; if (dir != PCI_DMA_TODEVICE) { for_each_sg(sgl, sg, nents, n) { dma_make_coherent(sg_phys(sg), PAGE_ALIGN(sg->length)); } } } struct dma_map_ops pci32_dma_ops = { .alloc = pci32_alloc_coherent, .free = pci32_free_coherent, .map_page = pci32_map_page, .unmap_page = pci32_unmap_page, .map_sg = pci32_map_sg, .unmap_sg = pci32_unmap_sg, .sync_single_for_cpu = pci32_sync_single_for_cpu, .sync_single_for_device = pci32_sync_single_for_device, .sync_sg_for_cpu = pci32_sync_sg_for_cpu, .sync_sg_for_device = pci32_sync_sg_for_device, }; EXPORT_SYMBOL(pci32_dma_ops); #endif /* CONFIG_PCI || CONFIG_SPARC_LEON */ #ifdef CONFIG_SPARC_LEON struct dma_map_ops *dma_ops = &pci32_dma_ops; #elif defined(CONFIG_SBUS) struct dma_map_ops *dma_ops = &sbus_dma_ops; #endif EXPORT_SYMBOL(dma_ops); /* * 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. */ int dma_supported(struct device *dev, u64 mask) { #ifdef CONFIG_PCI if (dev->bus == &pci_bus_type) return 1; #endif return 0; } EXPORT_SYMBOL(dma_supported); #ifdef CONFIG_PROC_FS static int sparc_io_proc_show(struct seq_file *m, void *v) { struct resource *root = m->private, *r; const char *nm; for (r = root->child; r != NULL; r = r->sibling) { if ((nm = r->name) == 0) nm = "???"; seq_printf(m, "%016llx-%016llx: %s\n", (unsigned long long)r->start, (unsigned long long)r->end, nm); } return 0; } static int sparc_io_proc_open(struct inode *inode, struct file *file) { return single_open(file, sparc_io_proc_show, PDE(inode)->data); } static const struct file_operations sparc_io_proc_fops = { .owner = THIS_MODULE, .open = sparc_io_proc_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; #endif /* CONFIG_PROC_FS */ static void register_proc_sparc_ioport(void) { #ifdef CONFIG_PROC_FS proc_create_data("io_map", 0, NULL, &sparc_io_proc_fops, &sparc_iomap); proc_create_data("dvma_map", 0, NULL, &sparc_io_proc_fops, &_sparc_dvma); #endif }