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Diffstat (limited to 'arch/sparc/kernel/ioport.c')
-rw-r--r-- | arch/sparc/kernel/ioport.c | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/arch/sparc/kernel/ioport.c b/arch/sparc/kernel/ioport.c new file mode 100644 index 000000000..7ceae24b0 --- /dev/null +++ b/arch/sparc/kernel/ioport.c @@ -0,0 +1,404 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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/dma-map-ops.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. + */ +static inline void dma_make_coherent(unsigned long pa, unsigned long len) +{ + if (sparc_cpu_model == sparc_leon) { + if (!sparc_leon3_snooping_enabled()) + leon_flush_dcache_all(); + } +} + +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(phys_addr_t offset, size_t size) +{ + char name[14]; + + sprintf(name, "phys_%08x", (u32)offset); + return _sparc_alloc_io(0, (unsigned long)offset, size, name); +} +EXPORT_SYMBOL(ioremap); + +/* + * Complementary 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()) != NULL) { + 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); +} + +/* + * Complementary 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); +} + +unsigned long sparc_dma_alloc_resource(struct device *dev, size_t len) +{ + struct resource *res; + + res = kzalloc(sizeof(*res), GFP_KERNEL); + if (!res) + return 0; + res->name = dev->of_node->full_name; + + if (allocate_resource(&_sparc_dvma, res, len, _sparc_dvma.start, + _sparc_dvma.end, PAGE_SIZE, NULL, NULL) != 0) { + printk("%s: cannot occupy 0x%zx", __func__, len); + kfree(res); + return 0; + } + + return res->start; +} + +bool sparc_dma_free_resource(void *cpu_addr, size_t size) +{ + unsigned long addr = (unsigned long)cpu_addr; + struct resource *res; + + res = lookup_resource(&_sparc_dvma, addr); + if (!res) { + printk("%s: cannot free %p\n", __func__, cpu_addr); + return false; + } + + if ((addr & (PAGE_SIZE - 1)) != 0) { + printk("%s: unaligned va %p\n", __func__, cpu_addr); + return false; + } + + size = PAGE_ALIGN(size); + if (resource_size(res) != size) { + printk("%s: region 0x%lx asked 0x%zx\n", + __func__, (long)resource_size(res), size); + return false; + } + + release_resource(res); + kfree(res); + return true; +} + +#ifdef CONFIG_SBUS + +void sbus_set_sbus64(struct device *dev, int x) +{ + printk("sbus_set_sbus64: unsupported\n"); +} +EXPORT_SYMBOL(sbus_set_sbus64); + +static int __init sparc_register_ioport(void) +{ + register_proc_sparc_ioport(); + + return 0; +} + +arch_initcall(sparc_register_ioport); + +#endif /* CONFIG_SBUS */ + + +/* Allocate and map kernel buffer using consistent mode DMA for a device. + * hwdev should be valid struct pci_dev pointer for PCI devices. + */ +void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp, unsigned long attrs) +{ + unsigned long addr; + void *va; + + if (!size || size > 256 * 1024) /* __get_free_pages() limit */ + return NULL; + + size = PAGE_ALIGN(size); + va = (void *) __get_free_pages(gfp | __GFP_ZERO, get_order(size)); + if (!va) { + printk("%s: no %zd pages\n", __func__, size >> PAGE_SHIFT); + return NULL; + } + + addr = sparc_dma_alloc_resource(dev, size); + if (!addr) + goto err_nomem; + + srmmu_mapiorange(0, virt_to_phys(va), addr, size); + + *dma_handle = virt_to_phys(va); + return (void *)addr; + +err_nomem: + free_pages((unsigned long)va, get_order(size)); + return NULL; +} + +/* Free and unmap a consistent DMA buffer. + * cpu_addr is what was returned arch_dma_alloc, size must be the same as what + * was passed into arch_dma_alloc, and likewise dma_addr must be the same as + * what *dma_ndler was set to. + * + * References to the memory and mappings associated with cpu_addr/dma_addr + * past this call are illegal. + */ +void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, + dma_addr_t dma_addr, unsigned long attrs) +{ + size = PAGE_ALIGN(size); + + if (!sparc_dma_free_resource(cpu_addr, size)) + return; + + dma_make_coherent(dma_addr, size); + srmmu_unmapiorange((unsigned long)cpu_addr, size); + free_pages((unsigned long)phys_to_virt(dma_addr), get_order(size)); +} + +/* IIep is write-through, not flushing on cpu to device transfer. */ + +void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, + enum dma_data_direction dir) +{ + if (dir != PCI_DMA_TODEVICE) + dma_make_coherent(paddr, PAGE_ALIGN(size)); +} + +#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) == NULL) nm = "???"; + seq_printf(m, "%016llx-%016llx: %s\n", + (unsigned long long)r->start, + (unsigned long long)r->end, nm); + } + + return 0; +} +#endif /* CONFIG_PROC_FS */ + +static void register_proc_sparc_ioport(void) +{ +#ifdef CONFIG_PROC_FS + proc_create_single_data("io_map", 0, NULL, sparc_io_proc_show, + &sparc_iomap); + proc_create_single_data("dvma_map", 0, NULL, sparc_io_proc_show, + &_sparc_dvma); +#endif +} |