diff options
Diffstat (limited to 'drivers/misc/hwmem/hwmem-main.c')
| -rw-r--r-- | drivers/misc/hwmem/hwmem-main.c | 833 |
1 files changed, 833 insertions, 0 deletions
diff --git a/drivers/misc/hwmem/hwmem-main.c b/drivers/misc/hwmem/hwmem-main.c new file mode 100644 index 00000000000..0010e45ff52 --- /dev/null +++ b/drivers/misc/hwmem/hwmem-main.c @@ -0,0 +1,833 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * + * Hardware memory driver, hwmem + * + * Author: Marcus Lorentzon <marcus.xm.lorentzon@stericsson.com> + * for ST-Ericsson. + * + * License terms: GNU General Public License (GPL), version 2. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/idr.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/pid.h> +#include <linux/list.h> +#include <linux/hwmem.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/io.h> +#include <asm/sizes.h> +#include "cache_handler.h" + +struct hwmem_alloc_threadg_info { + struct list_head list; + + struct pid *threadg_pid; /* Ref counted */ + + enum hwmem_access access; +}; + +struct hwmem_alloc { + struct list_head list; + + atomic_t ref_cnt; + enum hwmem_alloc_flags flags; + u32 paddr; + void *kaddr; + u32 size; + u32 name; + + /* Access control */ + enum hwmem_access default_access; + struct list_head threadg_info_list; + + /* Cache handling */ + struct cach_buf cach_buf; +}; + +static struct platform_device *hwdev; + +static u32 hwmem_paddr; +static u32 hwmem_size; + +static LIST_HEAD(alloc_list); +static DEFINE_IDR(global_idr); +static DEFINE_MUTEX(lock); + +static void vm_open(struct vm_area_struct *vma); +static void vm_close(struct vm_area_struct *vma); +static struct vm_operations_struct vm_ops = { + .open = vm_open, + .close = vm_close, +}; + +#ifdef CONFIG_DEBUG_FS + +static int debugfs_allocs_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos); +static const struct file_operations debugfs_allocs_fops = { + .owner = THIS_MODULE, + .read = debugfs_allocs_read, +}; + +#endif /* #ifdef CONFIG_DEBUG_FS */ + +static void clean_alloc_list(void); +static void kunmap_alloc(struct hwmem_alloc *alloc); + +/* Helpers */ + +static u32 get_alloc_offset(struct hwmem_alloc *alloc) +{ + return alloc->paddr - hwmem_paddr; +} + +static void destroy_hwmem_alloc_threadg_info( + struct hwmem_alloc_threadg_info *info) +{ + if (info->threadg_pid) + put_pid(info->threadg_pid); + + kfree(info); +} + +static void clean_hwmem_alloc_threadg_info_list(struct hwmem_alloc *alloc) +{ + struct hwmem_alloc_threadg_info *info; + struct hwmem_alloc_threadg_info *tmp; + + list_for_each_entry_safe(info, tmp, &(alloc->threadg_info_list), list) { + list_del(&info->list); + destroy_hwmem_alloc_threadg_info(info); + } +} + +static enum hwmem_access get_access(struct hwmem_alloc *alloc) +{ + struct hwmem_alloc_threadg_info *info; + struct pid *my_pid; + bool found = false; + + my_pid = find_get_pid(task_tgid_nr(current)); + if (!my_pid) + return 0; + + list_for_each_entry(info, &(alloc->threadg_info_list), list) { + if (info->threadg_pid == my_pid) { + found = true; + break; + } + } + + put_pid(my_pid); + + if (found) + return info->access; + else + return alloc->default_access; +} + +static void clear_alloc_mem(struct hwmem_alloc *alloc) +{ + cach_set_domain(&alloc->cach_buf, HWMEM_ACCESS_WRITE, + HWMEM_DOMAIN_CPU, NULL); + + memset(alloc->kaddr, 0, alloc->size); +} + +static void clean_alloc(struct hwmem_alloc *alloc) +{ + if (alloc->name) { + idr_remove(&global_idr, alloc->name); + alloc->name = 0; + } + + alloc->flags = 0; + + clean_hwmem_alloc_threadg_info_list(alloc); + + kunmap_alloc(alloc); +} + +static void destroy_alloc(struct hwmem_alloc *alloc) +{ + clean_alloc(alloc); + + kfree(alloc); +} + +static void __hwmem_release(struct hwmem_alloc *alloc) +{ + struct hwmem_alloc *other; + + clean_alloc(alloc); + + other = list_entry(alloc->list.prev, struct hwmem_alloc, list); + if ((alloc->list.prev != &alloc_list) && + atomic_read(&other->ref_cnt) == 0) { + other->size += alloc->size; + list_del(&alloc->list); + destroy_alloc(alloc); + alloc = other; + } + other = list_entry(alloc->list.next, struct hwmem_alloc, list); + if ((alloc->list.next != &alloc_list) && + atomic_read(&other->ref_cnt) == 0) { + alloc->size += other->size; + list_del(&other->list); + destroy_alloc(other); + } +} + +static struct hwmem_alloc *find_free_alloc_bestfit(u32 size) +{ + u32 best_diff = ~0; + struct hwmem_alloc *alloc = NULL, *i; + + list_for_each_entry(i, &alloc_list, list) { + u32 diff = i->size - size; + if (atomic_read(&i->ref_cnt) > 0 || i->size < size) + continue; + if (diff < best_diff) { + alloc = i; + best_diff = diff; + } + } + + return alloc != NULL ? alloc : ERR_PTR(-ENOMEM); +} + +static struct hwmem_alloc *split_allocation(struct hwmem_alloc *alloc, + u32 new_alloc_size) +{ + struct hwmem_alloc *new_alloc; + + new_alloc = kzalloc(sizeof(struct hwmem_alloc), GFP_KERNEL); + if (new_alloc == NULL) + return ERR_PTR(-ENOMEM); + + atomic_inc(&new_alloc->ref_cnt); + INIT_LIST_HEAD(&new_alloc->threadg_info_list); + new_alloc->paddr = alloc->paddr; + new_alloc->size = new_alloc_size; + alloc->size -= new_alloc_size; + alloc->paddr += new_alloc_size; + + list_add_tail(&new_alloc->list, &alloc->list); + + return new_alloc; +} + +static int init_alloc_list(void) +{ + /* + * Hack to not get any allocs that cross a 64MiB boundary as B2R2 can't + * handle that. + */ + int ret; + u32 curr_pos = hwmem_paddr; + u32 hwmem_end = hwmem_paddr + hwmem_size; + u32 next_64mib_boundary = (curr_pos + SZ_64M) & ~(SZ_64M - 1); + struct hwmem_alloc *alloc; + + if (PAGE_SIZE >= SZ_64M) { + dev_err(&hwdev->dev, "PAGE_SIZE >= SZ_64M\n"); + return -ENOMSG; + } + + while (next_64mib_boundary < hwmem_end) { + if (next_64mib_boundary - curr_pos > PAGE_SIZE) { + alloc = kzalloc(sizeof(struct hwmem_alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = next_64mib_boundary - curr_pos - + PAGE_SIZE; + INIT_LIST_HEAD(&alloc->threadg_info_list); + list_add_tail(&alloc->list, &alloc_list); + curr_pos = alloc->paddr + alloc->size; + } + + alloc = kzalloc(sizeof(struct hwmem_alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = PAGE_SIZE; + atomic_inc(&alloc->ref_cnt); + INIT_LIST_HEAD(&alloc->threadg_info_list); + list_add_tail(&alloc->list, &alloc_list); + curr_pos = alloc->paddr + alloc->size; + + next_64mib_boundary += SZ_64M; + } + + alloc = kzalloc(sizeof(struct hwmem_alloc), GFP_KERNEL); + if (alloc == NULL) { + ret = -ENOMEM; + goto error; + } + alloc->paddr = curr_pos; + alloc->size = hwmem_end - curr_pos; + INIT_LIST_HEAD(&alloc->threadg_info_list); + list_add_tail(&alloc->list, &alloc_list); + + return 0; + +error: + clean_alloc_list(); + + return ret; +} + +static void clean_alloc_list(void) +{ + while (list_empty(&alloc_list) == 0) { + struct hwmem_alloc *i = list_first_entry(&alloc_list, + struct hwmem_alloc, list); + + list_del(&i->list); + + destroy_alloc(i); + } +} + +static int kmap_alloc(struct hwmem_alloc *alloc) +{ + int ret; + pgprot_t pgprot; + + struct vm_struct *area = get_vm_area(alloc->size, VM_IOREMAP); + if (area == NULL) { + dev_info(&hwdev->dev, "Failed to allocate %u bytes virtual" + " memory", alloc->size); + return -ENOMSG; + } + + pgprot = PAGE_KERNEL; + cach_set_pgprot_cache_options(&alloc->cach_buf, &pgprot); + + ret = ioremap_page_range((unsigned long)area->addr, + (unsigned long)area->addr + alloc->size, alloc->paddr, pgprot); + if (ret < 0) { + dev_info(&hwdev->dev, "Failed to map %#x - %#x", alloc->paddr, + alloc->paddr + alloc->size); + goto failed_to_map; + } + + alloc->kaddr = area->addr; + + return 0; + +failed_to_map: + area = remove_vm_area(area->addr); + if (area == NULL) + dev_err(&hwdev->dev, + "Failed to unmap alloc, resource leak!\n"); + + kfree(area); + + return ret; +} + +static void kunmap_alloc(struct hwmem_alloc *alloc) +{ + struct vm_struct *area; + + if (alloc->kaddr == NULL) + return; + + area = remove_vm_area(alloc->kaddr); + if (area == NULL) { + dev_err(&hwdev->dev, + "Failed to unmap alloc, resource leak!\n"); + return; + } + + kfree(area); + + alloc->kaddr = NULL; +} + +/* HWMEM API */ + +struct hwmem_alloc *hwmem_alloc(u32 size, enum hwmem_alloc_flags flags, + enum hwmem_access def_access, enum hwmem_mem_type mem_type) +{ + struct hwmem_alloc *alloc; + int ret; + + if (!hwdev) { + printk(KERN_ERR "hwmem: Badly configured\n"); + return ERR_PTR(-EINVAL); + } + + if (size == 0) + return ERR_PTR(-EINVAL); + + mutex_lock(&lock); + + size = PAGE_ALIGN(size); + + alloc = find_free_alloc_bestfit(size); + if (IS_ERR(alloc)) { + dev_info(&hwdev->dev, "Allocation failed, no free slot\n"); + goto no_slot; + } + + if (size < alloc->size) { + alloc = split_allocation(alloc, size); + if (IS_ERR(alloc)) + goto split_alloc_failed; + } else { + atomic_inc(&alloc->ref_cnt); + } + + alloc->flags = flags; + alloc->default_access = def_access; + cach_init_buf(&alloc->cach_buf, alloc->flags, alloc->size); + ret = kmap_alloc(alloc); + if (ret < 0) + goto kmap_alloc_failed; + cach_set_buf_addrs(&alloc->cach_buf, alloc->kaddr, alloc->paddr); + + clear_alloc_mem(alloc); + + goto out; + +kmap_alloc_failed: + __hwmem_release(alloc); + alloc = ERR_PTR(ret); +split_alloc_failed: +no_slot: + +out: + mutex_unlock(&lock); + + return alloc; +} +EXPORT_SYMBOL(hwmem_alloc); + +void hwmem_release(struct hwmem_alloc *alloc) +{ + mutex_lock(&lock); + + if (atomic_dec_and_test(&alloc->ref_cnt)) + __hwmem_release(alloc); + + mutex_unlock(&lock); +} +EXPORT_SYMBOL(hwmem_release); + +int hwmem_set_domain(struct hwmem_alloc *alloc, enum hwmem_access access, + enum hwmem_domain domain, struct hwmem_region *region) +{ + mutex_lock(&lock); + + cach_set_domain(&alloc->cach_buf, access, domain, region); + + mutex_unlock(&lock); + + return 0; +} +EXPORT_SYMBOL(hwmem_set_domain); + +int hwmem_pin(struct hwmem_alloc *alloc, uint32_t *phys_addr, + uint32_t *scattered_phys_addrs) +{ + mutex_lock(&lock); + + *phys_addr = alloc->paddr; + + mutex_unlock(&lock); + + return 0; +} +EXPORT_SYMBOL(hwmem_pin); + +void hwmem_unpin(struct hwmem_alloc *alloc) +{ +} +EXPORT_SYMBOL(hwmem_unpin); + +static void vm_open(struct vm_area_struct *vma) +{ + atomic_inc(&((struct hwmem_alloc *)vma->vm_private_data)->ref_cnt); +} + +static void vm_close(struct vm_area_struct *vma) +{ + hwmem_release((struct hwmem_alloc *)vma->vm_private_data); +} + +int hwmem_mmap(struct hwmem_alloc *alloc, struct vm_area_struct *vma) +{ + int ret = 0; + unsigned long vma_size = vma->vm_end - vma->vm_start; + enum hwmem_access access; + mutex_lock(&lock); + + access = get_access(alloc); + + /* Check permissions */ + if ((!(access & HWMEM_ACCESS_WRITE) && + (vma->vm_flags & VM_WRITE)) || + (!(access & HWMEM_ACCESS_READ) && + (vma->vm_flags & VM_READ))) { + ret = -EPERM; + goto illegal_access; + } + + if (vma_size > (unsigned long)alloc->size) { + ret = -EINVAL; + goto illegal_size; + } + + /* + * We don't want Linux to do anything (merging etc) with our VMAs as + * the offset is not necessarily valid + */ + vma->vm_flags |= VM_SPECIAL; + cach_set_pgprot_cache_options(&alloc->cach_buf, &vma->vm_page_prot); + vma->vm_private_data = (void *)alloc; + atomic_inc(&alloc->ref_cnt); + vma->vm_ops = &vm_ops; + + ret = remap_pfn_range(vma, vma->vm_start, alloc->paddr >> PAGE_SHIFT, + min(vma_size, (unsigned long)alloc->size), vma->vm_page_prot); + if (ret < 0) + goto map_failed; + + goto out; + +map_failed: + atomic_dec(&alloc->ref_cnt); +illegal_size: +illegal_access: + +out: + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_mmap); + +void *hwmem_kmap(struct hwmem_alloc *alloc) +{ + void *ret; + + mutex_lock(&lock); + + ret = alloc->kaddr; + + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_kmap); + +void hwmem_kunmap(struct hwmem_alloc *alloc) +{ +} +EXPORT_SYMBOL(hwmem_kunmap); + +int hwmem_set_access(struct hwmem_alloc *alloc, + enum hwmem_access access, pid_t pid_nr) +{ + int ret; + struct hwmem_alloc_threadg_info *info; + struct pid *pid; + bool found = false; + + pid = find_get_pid(pid_nr); + if (!pid) { + ret = -EINVAL; + goto error_get_pid; + } + + list_for_each_entry(info, &(alloc->threadg_info_list), list) { + if (info->threadg_pid == pid) { + found = true; + break; + } + } + + if (!found) { + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + ret = -ENOMEM; + goto error_alloc_info; + } + + info->threadg_pid = pid; + info->access = access; + + list_add_tail(&(info->list), &(alloc->threadg_info_list)); + } else { + info->access = access; + } + + return 0; + +error_alloc_info: + put_pid(pid); +error_get_pid: + return ret; +} +EXPORT_SYMBOL(hwmem_set_access); + +void hwmem_get_info(struct hwmem_alloc *alloc, uint32_t *size, + enum hwmem_mem_type *mem_type, enum hwmem_access *access) +{ + mutex_lock(&lock); + + *size = alloc->size; + *mem_type = HWMEM_MEM_CONTIGUOUS_SYS; + *access = get_access(alloc); + + mutex_unlock(&lock); +} +EXPORT_SYMBOL(hwmem_get_info); + +int hwmem_get_name(struct hwmem_alloc *alloc) +{ + int ret = 0, name; + + mutex_lock(&lock); + + if (alloc->name != 0) { + ret = alloc->name; + goto out; + } + + while (true) { + if (idr_pre_get(&global_idr, GFP_KERNEL) == 0) { + ret = -ENOMEM; + goto pre_get_id_failed; + } + + ret = idr_get_new_above(&global_idr, alloc, 1, &name); + if (ret == 0) + break; + else if (ret != -EAGAIN) + goto get_id_failed; + } + + alloc->name = name; + + ret = name; + goto out; + +get_id_failed: +pre_get_id_failed: + +out: + mutex_unlock(&lock); + + return ret; +} +EXPORT_SYMBOL(hwmem_get_name); + +struct hwmem_alloc *hwmem_resolve_by_name(s32 name) +{ + struct hwmem_alloc *alloc; + + mutex_lock(&lock); + + alloc = idr_find(&global_idr, name); + if (alloc == NULL) { + alloc = ERR_PTR(-EINVAL); + goto find_failed; + } + atomic_inc(&alloc->ref_cnt); + + goto out; + +find_failed: + +out: + mutex_unlock(&lock); + + return alloc; +} +EXPORT_SYMBOL(hwmem_resolve_by_name); + +/* Debug */ + +static int print_alloc(struct hwmem_alloc *alloc, char **buf, size_t buf_size) +{ + int ret; + + if (buf_size < 134) + return -EINVAL; + + ret = sprintf(*buf, "paddr: %#10x\tsize: %10u\tref cnt: %2i\t" + "name: %#10x\tflags: %#4x\t$ settings: %#4x\t" + "def acc: %#3x\n", alloc->paddr, alloc->size, + atomic_read(&alloc->ref_cnt), alloc->name, + alloc->flags, alloc->cach_buf.cache_settings, + alloc->default_access); + if (ret < 0) + return -ENOMSG; + + *buf += ret; + + return 0; +} + +#ifdef CONFIG_DEBUG_FS + +static int debugfs_allocs_read(struct file *file, char __user *buf, + size_t count, loff_t *f_pos) +{ + /* + * We assume the supplied buffer and PAGE_SIZE is large enough to hold + * information about at least one alloc, if not no data will be + * returned. + */ + + int ret; + struct hwmem_alloc *curr_alloc; + char *local_buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + char *local_buf_pos = local_buf; + size_t available_space = min((size_t)PAGE_SIZE, count); + /* private_data is intialized to NULL in open which I assume is 0. */ + u32 *curr_pos = (u32 *)&file->private_data; + size_t bytes_read; + + if (local_buf == NULL) + return -ENOMEM; + + mutex_lock(&lock); + + list_for_each_entry(curr_alloc, &alloc_list, list) { + u32 alloc_offset = get_alloc_offset(curr_alloc); + + if (alloc_offset < *curr_pos) + continue; + + ret = print_alloc(curr_alloc, &local_buf_pos, available_space - + (size_t)(local_buf_pos - local_buf)); + if (ret == -EINVAL) /* No more room */ + break; + else if (ret < 0) + goto out; + + *curr_pos = alloc_offset + 1; + } + + bytes_read = (size_t)(local_buf_pos - local_buf); + + ret = copy_to_user(buf, local_buf, bytes_read); + if (ret < 0) + goto out; + + ret = bytes_read; + +out: + kfree(local_buf); + + mutex_unlock(&lock); + + return ret; +} + +static void init_debugfs(void) +{ + /* Hwmem is never unloaded so dropping the dentrys is ok. */ + struct dentry *debugfs_root_dir = debugfs_create_dir("hwmem", NULL); + (void)debugfs_create_file("allocs", 0444, debugfs_root_dir, 0, + &debugfs_allocs_fops); +} + +#endif /* #ifdef CONFIG_DEBUG_FS */ + +/* Module */ + +extern int hwmem_ioctl_init(void); +extern void hwmem_ioctl_exit(void); + +static int __devinit hwmem_probe(struct platform_device *pdev) +{ + int ret = 0; + struct hwmem_platform_data *platform_data = pdev->dev.platform_data; + + if (hwdev || platform_data->size == 0 || + platform_data->start != PAGE_ALIGN(platform_data->start) || + platform_data->size != PAGE_ALIGN(platform_data->size)) { + dev_err(&pdev->dev, "hwdev || platform_data->size == 0 ||" + "platform_data->start !=" + " PAGE_ALIGN(platform_data->start) ||" + "platform_data->size !=" + " PAGE_ALIGN(platform_data->size)\n"); + return -EINVAL; + } + + hwdev = pdev; + hwmem_paddr = platform_data->start; + hwmem_size = platform_data->size; + + /* + * No need to flush the caches here. If we can keep track of the cache + * content then none of our memory will be in the caches, if we can't + * keep track of the cache content we always assume all our memory is + * in the caches. + */ + + ret = init_alloc_list(); + if (ret < 0) + goto init_alloc_list_failed; + + ret = hwmem_ioctl_init(); + if (ret) + goto ioctl_init_failed; + +#ifdef CONFIG_DEBUG_FS + init_debugfs(); +#endif + + dev_info(&pdev->dev, "Hwmem probed, device contains %#x bytes\n", + hwmem_size); + + goto out; + +ioctl_init_failed: + clean_alloc_list(); +init_alloc_list_failed: + hwdev = NULL; + +out: + return ret; +} + +static struct platform_driver hwmem_driver = { + .probe = hwmem_probe, + .driver = { + .name = "hwmem", + }, +}; + +static int __init hwmem_init(void) +{ + return platform_driver_register(&hwmem_driver); +} +subsys_initcall(hwmem_init); + +MODULE_AUTHOR("Marcus Lorentzon <marcus.xm.lorentzon@stericsson.com>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Hardware memory driver"); + |