diff options
Diffstat (limited to 'arch/powerpc/sysdev/scom.c')
| -rw-r--r-- | arch/powerpc/sysdev/scom.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/scom.c b/arch/powerpc/sysdev/scom.c new file mode 100644 index 00000000000..b2593ce30c9 --- /dev/null +++ b/arch/powerpc/sysdev/scom.c @@ -0,0 +1,192 @@ +/* + * Copyright 2010 Benjamin Herrenschmidt, IBM Corp + * <benh@kernel.crashing.org> + * and David Gibson, IBM Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/debugfs.h> +#include <linux/slab.h> +#include <asm/prom.h> +#include <asm/scom.h> + +const struct scom_controller *scom_controller; +EXPORT_SYMBOL_GPL(scom_controller); + +struct device_node *scom_find_parent(struct device_node *node) +{ + struct device_node *par, *tmp; + const u32 *p; + + for (par = of_node_get(node); par;) { + if (of_get_property(par, "scom-controller", NULL)) + break; + p = of_get_property(par, "scom-parent", NULL); + tmp = par; + if (p == NULL) + par = of_get_parent(par); + else + par = of_find_node_by_phandle(*p); + of_node_put(tmp); + } + return par; +} +EXPORT_SYMBOL_GPL(scom_find_parent); + +scom_map_t scom_map_device(struct device_node *dev, int index) +{ + struct device_node *parent; + unsigned int cells, size; + const u32 *prop; + u64 reg, cnt; + scom_map_t ret; + + parent = scom_find_parent(dev); + + if (parent == NULL) + return 0; + + prop = of_get_property(parent, "#scom-cells", NULL); + cells = prop ? *prop : 1; + + prop = of_get_property(dev, "scom-reg", &size); + if (!prop) + return 0; + size >>= 2; + + if (index >= (size / (2*cells))) + return 0; + + reg = of_read_number(&prop[index * cells * 2], cells); + cnt = of_read_number(&prop[index * cells * 2 + cells], cells); + + ret = scom_map(parent, reg, cnt); + of_node_put(parent); + + return ret; +} +EXPORT_SYMBOL_GPL(scom_map_device); + +#ifdef CONFIG_SCOM_DEBUGFS +struct scom_debug_entry { + struct device_node *dn; + unsigned long addr; + scom_map_t map; + spinlock_t lock; + char name[8]; + struct debugfs_blob_wrapper blob; +}; + +static int scom_addr_set(void *data, u64 val) +{ + struct scom_debug_entry *ent = data; + + ent->addr = 0; + scom_unmap(ent->map); + + ent->map = scom_map(ent->dn, val, 1); + if (scom_map_ok(ent->map)) + ent->addr = val; + else + return -EFAULT; + + return 0; +} + +static int scom_addr_get(void *data, u64 *val) +{ + struct scom_debug_entry *ent = data; + *val = ent->addr; + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(scom_addr_fops, scom_addr_get, scom_addr_set, + "0x%llx\n"); + +static int scom_val_set(void *data, u64 val) +{ + struct scom_debug_entry *ent = data; + + if (!scom_map_ok(ent->map)) + return -EFAULT; + + scom_write(ent->map, 0, val); + + return 0; +} + +static int scom_val_get(void *data, u64 *val) +{ + struct scom_debug_entry *ent = data; + + if (!scom_map_ok(ent->map)) + return -EFAULT; + + *val = scom_read(ent->map, 0); + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(scom_val_fops, scom_val_get, scom_val_set, + "0x%llx\n"); + +static int scom_debug_init_one(struct dentry *root, struct device_node *dn, + int i) +{ + struct scom_debug_entry *ent; + struct dentry *dir; + + ent = kzalloc(sizeof(*ent), GFP_KERNEL); + if (!ent) + return -ENOMEM; + + ent->dn = of_node_get(dn); + ent->map = SCOM_MAP_INVALID; + spin_lock_init(&ent->lock); + snprintf(ent->name, 8, "scom%d", i); + ent->blob.data = dn->full_name; + ent->blob.size = strlen(dn->full_name); + + dir = debugfs_create_dir(ent->name, root); + if (!dir) { + of_node_put(dn); + kfree(ent); + return -1; + } + + debugfs_create_file("addr", 0600, dir, ent, &scom_addr_fops); + debugfs_create_file("value", 0600, dir, ent, &scom_val_fops); + debugfs_create_blob("path", 0400, dir, &ent->blob); + + return 0; +} + +static int scom_debug_init(void) +{ + struct device_node *dn; + struct dentry *root; + int i, rc; + + root = debugfs_create_dir("scom", powerpc_debugfs_root); + if (!root) + return -1; + + i = rc = 0; + for_each_node_with_property(dn, "scom-controller") + rc |= scom_debug_init_one(root, dn, i++); + + return rc; +} +device_initcall(scom_debug_init); +#endif /* CONFIG_SCOM_DEBUGFS */ |