| /* |
| * arch/sh/kernel/cpu/sh4/sq.c |
| * |
| * General management API for SH-4 integrated Store Queues |
| * |
| * Copyright (C) 2001 - 2006 Paul Mundt |
| * Copyright (C) 2001, 2002 M. R. Brown |
| * |
| * 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. |
| */ |
| #include <linux/init.h> |
| #include <linux/cpu.h> |
| #include <linux/bitmap.h> |
| #include <linux/sysdev.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/vmalloc.h> |
| #include <linux/mm.h> |
| #include <linux/io.h> |
| #include <asm/page.h> |
| #include <asm/cacheflush.h> |
| #include <asm/cpu/sq.h> |
| |
| struct sq_mapping; |
| |
| struct sq_mapping { |
| const char *name; |
| |
| unsigned long sq_addr; |
| unsigned long addr; |
| unsigned int size; |
| |
| struct sq_mapping *next; |
| }; |
| |
| static struct sq_mapping *sq_mapping_list; |
| static DEFINE_SPINLOCK(sq_mapping_lock); |
| static struct kmem_cache *sq_cache; |
| static unsigned long *sq_bitmap; |
| |
| #define store_queue_barrier() \ |
| do { \ |
| (void)ctrl_inl(P4SEG_STORE_QUE); \ |
| ctrl_outl(0, P4SEG_STORE_QUE + 0); \ |
| ctrl_outl(0, P4SEG_STORE_QUE + 8); \ |
| } while (0); |
| |
| /** |
| * sq_flush_range - Flush (prefetch) a specific SQ range |
| * @start: the store queue address to start flushing from |
| * @len: the length to flush |
| * |
| * Flushes the store queue cache from @start to @start + @len in a |
| * linear fashion. |
| */ |
| void sq_flush_range(unsigned long start, unsigned int len) |
| { |
| volatile unsigned long *sq = (unsigned long *)start; |
| |
| /* Flush the queues */ |
| for (len >>= 5; len--; sq += 8) |
| prefetchw((void *)sq); |
| |
| /* Wait for completion */ |
| store_queue_barrier(); |
| } |
| EXPORT_SYMBOL(sq_flush_range); |
| |
| static inline void sq_mapping_list_add(struct sq_mapping *map) |
| { |
| struct sq_mapping **p, *tmp; |
| |
| spin_lock_irq(&sq_mapping_lock); |
| |
| p = &sq_mapping_list; |
| while ((tmp = *p) != NULL) |
| p = &tmp->next; |
| |
| map->next = tmp; |
| *p = map; |
| |
| spin_unlock_irq(&sq_mapping_lock); |
| } |
| |
| static inline void sq_mapping_list_del(struct sq_mapping *map) |
| { |
| struct sq_mapping **p, *tmp; |
| |
| spin_lock_irq(&sq_mapping_lock); |
| |
| for (p = &sq_mapping_list; (tmp = *p); p = &tmp->next) |
| if (tmp == map) { |
| *p = tmp->next; |
| break; |
| } |
| |
| spin_unlock_irq(&sq_mapping_lock); |
| } |
| |
| static int __sq_remap(struct sq_mapping *map, unsigned long flags) |
| { |
| #if defined(CONFIG_MMU) |
| struct vm_struct *vma; |
| |
| vma = __get_vm_area(map->size, VM_ALLOC, map->sq_addr, SQ_ADDRMAX); |
| if (!vma) |
| return -ENOMEM; |
| |
| vma->phys_addr = map->addr; |
| |
| if (ioremap_page_range((unsigned long)vma->addr, |
| (unsigned long)vma->addr + map->size, |
| vma->phys_addr, __pgprot(flags))) { |
| vunmap(vma->addr); |
| return -EAGAIN; |
| } |
| #else |
| /* |
| * Without an MMU (or with it turned off), this is much more |
| * straightforward, as we can just load up each queue's QACR with |
| * the physical address appropriately masked. |
| */ |
| ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR0); |
| ctrl_outl(((map->addr >> 26) << 2) & 0x1c, SQ_QACR1); |
| #endif |
| |
| return 0; |
| } |
| |
| /** |
| * sq_remap - Map a physical address through the Store Queues |
| * @phys: Physical address of mapping. |
| * @size: Length of mapping. |
| * @name: User invoking mapping. |
| * @flags: Protection flags. |
| * |
| * Remaps the physical address @phys through the next available store queue |
| * address of @size length. @name is logged at boot time as well as through |
| * the sysfs interface. |
| */ |
| unsigned long sq_remap(unsigned long phys, unsigned int size, |
| const char *name, unsigned long flags) |
| { |
| struct sq_mapping *map; |
| unsigned long end; |
| unsigned int psz; |
| int ret, page; |
| |
| /* Don't allow wraparound or zero size */ |
| end = phys + size - 1; |
| if (unlikely(!size || end < phys)) |
| return -EINVAL; |
| /* Don't allow anyone to remap normal memory.. */ |
| if (unlikely(phys < virt_to_phys(high_memory))) |
| return -EINVAL; |
| |
| phys &= PAGE_MASK; |
| size = PAGE_ALIGN(end + 1) - phys; |
| |
| map = kmem_cache_alloc(sq_cache, GFP_KERNEL); |
| if (unlikely(!map)) |
| return -ENOMEM; |
| |
| map->addr = phys; |
| map->size = size; |
| map->name = name; |
| |
| page = bitmap_find_free_region(sq_bitmap, 0x04000000 >> PAGE_SHIFT, |
| get_order(map->size)); |
| if (unlikely(page < 0)) { |
| ret = -ENOSPC; |
| goto out; |
| } |
| |
| map->sq_addr = P4SEG_STORE_QUE + (page << PAGE_SHIFT); |
| |
| ret = __sq_remap(map, pgprot_val(PAGE_KERNEL_NOCACHE) | flags); |
| if (unlikely(ret != 0)) |
| goto out; |
| |
| psz = (size + (PAGE_SIZE - 1)) >> PAGE_SHIFT; |
| pr_info("sqremap: %15s [%4d page%s] va 0x%08lx pa 0x%08lx\n", |
| likely(map->name) ? map->name : "???", |
| psz, psz == 1 ? " " : "s", |
| map->sq_addr, map->addr); |
| |
| sq_mapping_list_add(map); |
| |
| return map->sq_addr; |
| |
| out: |
| kmem_cache_free(sq_cache, map); |
| return ret; |
| } |
| EXPORT_SYMBOL(sq_remap); |
| |
| /** |
| * sq_unmap - Unmap a Store Queue allocation |
| * @map: Pre-allocated Store Queue mapping. |
| * |
| * Unmaps the store queue allocation @map that was previously created by |
| * sq_remap(). Also frees up the pte that was previously inserted into |
| * the kernel page table and discards the UTLB translation. |
| */ |
| void sq_unmap(unsigned long vaddr) |
| { |
| struct sq_mapping **p, *map; |
| struct vm_struct *vma; |
| int page; |
| |
| for (p = &sq_mapping_list; (map = *p); p = &map->next) |
| if (map->sq_addr == vaddr) |
| break; |
| |
| if (unlikely(!map)) { |
| printk("%s: bad store queue address 0x%08lx\n", |
| __FUNCTION__, vaddr); |
| return; |
| } |
| |
| page = (map->sq_addr - P4SEG_STORE_QUE) >> PAGE_SHIFT; |
| bitmap_release_region(sq_bitmap, page, get_order(map->size)); |
| |
| #ifdef CONFIG_MMU |
| vma = remove_vm_area((void *)(map->sq_addr & PAGE_MASK)); |
| if (!vma) { |
| printk(KERN_ERR "%s: bad address 0x%08lx\n", |
| __FUNCTION__, map->sq_addr); |
| return; |
| } |
| #endif |
| |
| sq_mapping_list_del(map); |
| |
| kmem_cache_free(sq_cache, map); |
| } |
| EXPORT_SYMBOL(sq_unmap); |
| |
| /* |
| * Needlessly complex sysfs interface. Unfortunately it doesn't seem like |
| * there is any other easy way to add things on a per-cpu basis without |
| * putting the directory entries somewhere stupid and having to create |
| * links in sysfs by hand back in to the per-cpu directories. |
| * |
| * Some day we may want to have an additional abstraction per store |
| * queue, but considering the kobject hell we already have to deal with, |
| * it's simply not worth the trouble. |
| */ |
| static struct kobject *sq_kobject[NR_CPUS]; |
| |
| struct sq_sysfs_attr { |
| struct attribute attr; |
| ssize_t (*show)(char *buf); |
| ssize_t (*store)(const char *buf, size_t count); |
| }; |
| |
| #define to_sq_sysfs_attr(attr) container_of(attr, struct sq_sysfs_attr, attr) |
| |
| static ssize_t sq_sysfs_show(struct kobject *kobj, struct attribute *attr, |
| char *buf) |
| { |
| struct sq_sysfs_attr *sattr = to_sq_sysfs_attr(attr); |
| |
| if (likely(sattr->show)) |
| return sattr->show(buf); |
| |
| return -EIO; |
| } |
| |
| static ssize_t sq_sysfs_store(struct kobject *kobj, struct attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct sq_sysfs_attr *sattr = to_sq_sysfs_attr(attr); |
| |
| if (likely(sattr->store)) |
| return sattr->store(buf, count); |
| |
| return -EIO; |
| } |
| |
| static ssize_t mapping_show(char *buf) |
| { |
| struct sq_mapping **list, *entry; |
| char *p = buf; |
| |
| for (list = &sq_mapping_list; (entry = *list); list = &entry->next) |
| p += sprintf(p, "%08lx-%08lx [%08lx]: %s\n", |
| entry->sq_addr, entry->sq_addr + entry->size, |
| entry->addr, entry->name); |
| |
| return p - buf; |
| } |
| |
| static ssize_t mapping_store(const char *buf, size_t count) |
| { |
| unsigned long base = 0, len = 0; |
| |
| sscanf(buf, "%lx %lx", &base, &len); |
| if (!base) |
| return -EIO; |
| |
| if (likely(len)) { |
| int ret = sq_remap(base, len, "Userspace", |
| pgprot_val(PAGE_SHARED)); |
| if (ret < 0) |
| return ret; |
| } else |
| sq_unmap(base); |
| |
| return count; |
| } |
| |
| static struct sq_sysfs_attr mapping_attr = |
| __ATTR(mapping, 0644, mapping_show, mapping_store); |
| |
| static struct attribute *sq_sysfs_attrs[] = { |
| &mapping_attr.attr, |
| NULL, |
| }; |
| |
| static struct sysfs_ops sq_sysfs_ops = { |
| .show = sq_sysfs_show, |
| .store = sq_sysfs_store, |
| }; |
| |
| static struct kobj_type ktype_percpu_entry = { |
| .sysfs_ops = &sq_sysfs_ops, |
| .default_attrs = sq_sysfs_attrs, |
| }; |
| |
| static int __devinit sq_sysdev_add(struct sys_device *sysdev) |
| { |
| unsigned int cpu = sysdev->id; |
| struct kobject *kobj; |
| |
| sq_kobject[cpu] = kzalloc(sizeof(struct kobject), GFP_KERNEL); |
| if (unlikely(!sq_kobject[cpu])) |
| return -ENOMEM; |
| |
| kobj = sq_kobject[cpu]; |
| kobj->parent = &sysdev->kobj; |
| kobject_set_name(kobj, "%s", "sq"); |
| kobj->ktype = &ktype_percpu_entry; |
| |
| return kobject_register(kobj); |
| } |
| |
| static int __devexit sq_sysdev_remove(struct sys_device *sysdev) |
| { |
| unsigned int cpu = sysdev->id; |
| struct kobject *kobj = sq_kobject[cpu]; |
| |
| kobject_unregister(kobj); |
| return 0; |
| } |
| |
| static struct sysdev_driver sq_sysdev_driver = { |
| .add = sq_sysdev_add, |
| .remove = __devexit_p(sq_sysdev_remove), |
| }; |
| |
| static int __init sq_api_init(void) |
| { |
| unsigned int nr_pages = 0x04000000 >> PAGE_SHIFT; |
| unsigned int size = (nr_pages + (BITS_PER_LONG - 1)) / BITS_PER_LONG; |
| int ret = -ENOMEM; |
| |
| printk(KERN_NOTICE "sq: Registering store queue API.\n"); |
| |
| sq_cache = kmem_cache_create("store_queue_cache", |
| sizeof(struct sq_mapping), 0, 0, |
| NULL, NULL); |
| if (unlikely(!sq_cache)) |
| return ret; |
| |
| sq_bitmap = kzalloc(size, GFP_KERNEL); |
| if (unlikely(!sq_bitmap)) |
| goto out; |
| |
| ret = sysdev_driver_register(&cpu_sysdev_class, &sq_sysdev_driver); |
| if (unlikely(ret != 0)) |
| goto out; |
| |
| return 0; |
| |
| out: |
| kfree(sq_bitmap); |
| kmem_cache_destroy(sq_cache); |
| |
| return ret; |
| } |
| |
| static void __exit sq_api_exit(void) |
| { |
| sysdev_driver_unregister(&cpu_sysdev_class, &sq_sysdev_driver); |
| kfree(sq_bitmap); |
| kmem_cache_destroy(sq_cache); |
| } |
| |
| module_init(sq_api_init); |
| module_exit(sq_api_exit); |
| |
| MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, M. R. Brown <mrbrown@0xd6.org>"); |
| MODULE_DESCRIPTION("Simple API for SH-4 integrated Store Queues"); |
| MODULE_LICENSE("GPL"); |