diff options
Diffstat (limited to 'arch/sh64/mm/ioremap.c')
-rw-r--r-- | arch/sh64/mm/ioremap.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/arch/sh64/mm/ioremap.c b/arch/sh64/mm/ioremap.c new file mode 100644 index 0000000..f4003da --- /dev/null +++ b/arch/sh64/mm/ioremap.c @@ -0,0 +1,469 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * arch/sh64/mm/ioremap.c + * + * Copyright (C) 2000, 2001 Paolo Alberelli + * Copyright (C) 2003, 2004 Paul Mundt + * + * Mostly derived from arch/sh/mm/ioremap.c which, in turn is mostly + * derived from arch/i386/mm/ioremap.c . + * + * (C) Copyright 1995 1996 Linus Torvalds + */ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/sched.h> +#include <linux/string.h> +#include <asm/io.h> +#include <asm/pgalloc.h> +#include <asm/tlbflush.h> +#include <linux/ioport.h> +#include <linux/bootmem.h> +#include <linux/proc_fs.h> + +static void shmedia_mapioaddr(unsigned long, unsigned long); +static unsigned long shmedia_ioremap(struct resource *, u32, int); + +static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size, + unsigned long phys_addr, unsigned long flags) +{ + unsigned long end; + unsigned long pfn; + pgprot_t pgprot = __pgprot(_PAGE_PRESENT | _PAGE_READ | + _PAGE_WRITE | _PAGE_DIRTY | + _PAGE_ACCESSED | _PAGE_SHARED | flags); + + address &= ~PMD_MASK; + end = address + size; + if (end > PMD_SIZE) + end = PMD_SIZE; + if (address >= end) + BUG(); + + pfn = phys_addr >> PAGE_SHIFT; + + pr_debug(" %s: pte %p address %lx size %lx phys_addr %lx\n", + __FUNCTION__,pte,address,size,phys_addr); + + do { + if (!pte_none(*pte)) { + printk("remap_area_pte: page already exists\n"); + BUG(); + } + + set_pte(pte, pfn_pte(pfn, pgprot)); + address += PAGE_SIZE; + pfn++; + pte++; + } while (address && (address < end)); +} + +static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size, + unsigned long phys_addr, unsigned long flags) +{ + unsigned long end; + + address &= ~PGDIR_MASK; + end = address + size; + + if (end > PGDIR_SIZE) + end = PGDIR_SIZE; + + phys_addr -= address; + + if (address >= end) + BUG(); + + do { + pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address); + if (!pte) + return -ENOMEM; + remap_area_pte(pte, address, end - address, address + phys_addr, flags); + address = (address + PMD_SIZE) & PMD_MASK; + pmd++; + } while (address && (address < end)); + return 0; +} + +static int remap_area_pages(unsigned long address, unsigned long phys_addr, + unsigned long size, unsigned long flags) +{ + int error; + pgd_t * dir; + unsigned long end = address + size; + + phys_addr -= address; + dir = pgd_offset_k(address); + flush_cache_all(); + if (address >= end) + BUG(); + spin_lock(&init_mm.page_table_lock); + do { + pmd_t *pmd = pmd_alloc(&init_mm, dir, address); + error = -ENOMEM; + if (!pmd) + break; + if (remap_area_pmd(pmd, address, end - address, + phys_addr + address, flags)) { + break; + } + error = 0; + address = (address + PGDIR_SIZE) & PGDIR_MASK; + dir++; + } while (address && (address < end)); + spin_unlock(&init_mm.page_table_lock); + flush_tlb_all(); + return 0; +} + +/* + * Generic mapping function (not visible outside): + */ + +/* + * Remap an arbitrary physical address space into the kernel virtual + * address space. Needed when the kernel wants to access high addresses + * directly. + * + * NOTE! We need to allow non-page-aligned mappings too: we will obviously + * have to convert them into an offset in a page-aligned mapping, but the + * caller shouldn't need to know that small detail. + */ +void * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags) +{ + void * addr; + struct vm_struct * area; + unsigned long offset, last_addr; + + /* Don't allow wraparound or zero size */ + last_addr = phys_addr + size - 1; + if (!size || last_addr < phys_addr) + return NULL; + + /* + * Mappings have to be page-aligned + */ + offset = phys_addr & ~PAGE_MASK; + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(last_addr + 1) - phys_addr; + + /* + * Ok, go for it.. + */ + area = get_vm_area(size, VM_IOREMAP); + pr_debug("Get vm_area returns %p addr %p\n",area,area->addr); + if (!area) + return NULL; + area->phys_addr = phys_addr; + addr = area->addr; + if (remap_area_pages((unsigned long)addr, phys_addr, size, flags)) { + vunmap(addr); + return NULL; + } + return (void *) (offset + (char *)addr); +} + +void iounmap(void *addr) +{ + struct vm_struct *area; + + vfree((void *) (PAGE_MASK & (unsigned long) addr)); + area = remove_vm_area((void *) (PAGE_MASK & (unsigned long) addr)); + if (!area) { + printk(KERN_ERR "iounmap: bad address %p\n", addr); + return; + } + + kfree(area); +} + +static struct resource shmedia_iomap = { + .name = "shmedia_iomap", + .start = IOBASE_VADDR + PAGE_SIZE, + .end = IOBASE_END - 1, +}; + +static void shmedia_mapioaddr(unsigned long pa, unsigned long va); +static void shmedia_unmapioaddr(unsigned long vaddr); +static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz); + +/* + * We have the same problem as the SPARC, so lets have the same comment: + * 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 + +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; +} + +static struct resource *shmedia_find_resource(struct resource *root, + unsigned long vaddr) +{ + struct resource *res; + + for (res = root->child; res; res = res->sibling) + if (res->start <= vaddr && res->end >= vaddr) + return res; + + return NULL; +} + +static unsigned long shmedia_alloc_io(unsigned long phys, unsigned long size, + const char *name) +{ + static int printed_full = 0; + struct xresource *xres; + struct resource *res; + char *tack; + int tlen; + + if (name == NULL) name = "???"; + + if ((xres = xres_alloc()) != 0) { + tack = xres->xname; + res = &xres->xres; + } else { + if (!printed_full) { + printk("%s: done with statics, switching to kmalloc\n", + __FUNCTION__); + printed_full = 1; + } + tlen = strlen(name); + tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL); + if (!tack) + return -ENOMEM; + memset(tack, 0, sizeof(struct resource)); + res = (struct resource *) tack; + tack += sizeof (struct resource); + } + + strncpy(tack, name, XNMLN); + tack[XNMLN] = 0; + res->name = tack; + + return shmedia_ioremap(res, phys, size); +} + +static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz) +{ + unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK); + unsigned long round_sz = (offset + sz + PAGE_SIZE-1) & PAGE_MASK; + unsigned long va; + unsigned int psz; + + if (allocate_resource(&shmedia_iomap, res, round_sz, + shmedia_iomap.start, shmedia_iomap.end, + PAGE_SIZE, NULL, NULL) != 0) { + panic("alloc_io_res(%s): cannot occupy\n", + (res->name != NULL)? res->name: "???"); + } + + va = res->start; + pa &= PAGE_MASK; + + psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE; + + /* log at boot time ... */ + printk("mapioaddr: %6s [%2d page%s] va 0x%08lx pa 0x%08x\n", + ((res->name != NULL) ? res->name : "???"), + psz, psz == 1 ? " " : "s", va, pa); + + for (psz = res->end - res->start + 1; psz != 0; psz -= PAGE_SIZE) { + shmedia_mapioaddr(pa, va); + va += PAGE_SIZE; + pa += PAGE_SIZE; + } + + res->start += offset; + res->end = res->start + sz - 1; /* not strictly necessary.. */ + + return res->start; +} + +static void shmedia_free_io(struct resource *res) +{ + unsigned long len = res->end - res->start + 1; + + BUG_ON((len & (PAGE_SIZE - 1)) != 0); + + while (len) { + len -= PAGE_SIZE; + shmedia_unmapioaddr(res->start + len); + } + + release_resource(res); +} + +static void *sh64_get_page(void) +{ + extern int after_bootmem; + void *page; + + if (after_bootmem) { + page = (void *)get_zeroed_page(GFP_ATOMIC); + } else { + page = alloc_bootmem_pages(PAGE_SIZE); + } + + if (!page || ((unsigned long)page & ~PAGE_MASK)) + panic("sh64_get_page: Out of memory already?\n"); + + return page; +} + +static void shmedia_mapioaddr(unsigned long pa, unsigned long va) +{ + pgd_t *pgdp; + pmd_t *pmdp; + pte_t *ptep, pte; + pgprot_t prot; + unsigned long flags = 1; /* 1 = CB0-1 device */ + + pr_debug("shmedia_mapiopage pa %08lx va %08lx\n", pa, va); + + pgdp = pgd_offset_k(va); + if (pgd_none(*pgdp) || !pgd_present(*pgdp)) { + pmdp = (pmd_t *)sh64_get_page(); + set_pgd(pgdp, __pgd((unsigned long)pmdp | _KERNPG_TABLE)); + } + + pmdp = pmd_offset(pgdp, va); + if (pmd_none(*pmdp) || !pmd_present(*pmdp) ) { + ptep = (pte_t *)sh64_get_page(); + set_pmd(pmdp, __pmd((unsigned long)ptep + _PAGE_TABLE)); + } + + prot = __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | + _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SHARED | flags); + + pte = pfn_pte(pa >> PAGE_SHIFT, prot); + ptep = pte_offset_kernel(pmdp, va); + + if (!pte_none(*ptep) && + pte_val(*ptep) != pte_val(pte)) + pte_ERROR(*ptep); + + set_pte(ptep, pte); + + flush_tlb_kernel_range(va, PAGE_SIZE); +} + +static void shmedia_unmapioaddr(unsigned long vaddr) +{ + pgd_t *pgdp; + pmd_t *pmdp; + pte_t *ptep; + + pgdp = pgd_offset_k(vaddr); + pmdp = pmd_offset(pgdp, vaddr); + + if (pmd_none(*pmdp) || pmd_bad(*pmdp)) + return; + + ptep = pte_offset_kernel(pmdp, vaddr); + + if (pte_none(*ptep) || !pte_present(*ptep)) + return; + + clear_page((void *)ptep); + pte_clear(&init_mm, vaddr, ptep); +} + +unsigned long onchip_remap(unsigned long phys, unsigned long size, const char *name) +{ + if (size < PAGE_SIZE) + size = PAGE_SIZE; + + return shmedia_alloc_io(phys, size, name); +} + +void onchip_unmap(unsigned long vaddr) +{ + struct resource *res; + unsigned int psz; + + res = shmedia_find_resource(&shmedia_iomap, vaddr); + if (!res) { + printk(KERN_ERR "%s: Failed to free 0x%08lx\n", + __FUNCTION__, vaddr); + return; + } + + psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE; + + printk(KERN_DEBUG "unmapioaddr: %6s [%2d page%s] freed\n", + res->name, psz, psz == 1 ? " " : "s"); + + shmedia_free_io(res); + + if ((char *)res >= (char *)xresv && + (char *)res < (char *)&xresv[XNRES]) { + xres_free((struct xresource *)res); + } else { + kfree(res); + } +} + +#ifdef CONFIG_PROC_FS +static int +ioremap_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, + void *data) +{ + char *p = buf, *e = buf + length; + struct resource *r; + const char *nm; + + for (r = ((struct resource *)data)->child; r != NULL; r = r->sibling) { + if (p + 32 >= e) /* Better than nothing */ + break; + if ((nm = r->name) == 0) nm = "???"; + p += sprintf(p, "%08lx-%08lx: %s\n", r->start, r->end, nm); + } + + return p-buf; +} +#endif /* CONFIG_PROC_FS */ + +static int __init register_proc_onchip(void) +{ +#ifdef CONFIG_PROC_FS + create_proc_read_entry("io_map",0,0, ioremap_proc_info, &shmedia_iomap); +#endif + return 0; +} + +__initcall(register_proc_onchip); |