summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--common/Makefile1
-rw-r--r--common/resource.c121
-rw-r--r--include/linux/ioport.h14
3 files changed, 136 insertions, 0 deletions
diff --git a/common/Makefile b/common/Makefile
index 55d9dbc..9bce479 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -27,6 +27,7 @@ obj-y += startup.o
obj-y += misc.o
obj-y += memsize.o
obj-y += filetype.o
+obj-y += resource.o
obj-$(CONFIG_MENU) += menu.o
obj-$(CONFIG_PASSWORD) += password.o
obj-$(CONFIG_MODULES) += module.o
diff --git a/common/resource.c b/common/resource.c
new file mode 100644
index 0000000..63e9c49
--- /dev/null
+++ b/common/resource.c
@@ -0,0 +1,121 @@
+/*
+ * resource.c - barebox resource management
+ *
+ * Copyright (c) 2011 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+#include <common.h>
+#include <malloc.h>
+#include <errno.h>
+#include <init.h>
+#include <linux/ioport.h>
+
+static int init_resource(struct resource *res, const char *name)
+{
+ INIT_LIST_HEAD(&res->children);
+ res->parent = NULL;
+ res->name = xstrdup(name);
+
+ return 0;
+}
+
+/*
+ * request a region.
+ * This will succedd when the requested region is completely inside
+ * the parent resource and does not conflict with any of the child
+ * resources.
+ */
+struct resource *request_region(struct resource *parent,
+ const char *name, resource_size_t start,
+ resource_size_t size)
+{
+ struct resource *r, *new;
+
+ /* outside parent resource? */
+ if (start < parent->start ||
+ start + size > parent->start + parent->size) {
+ debug("%s: 0x%08x:0x%08x outside parent resource 0x%08x:0x%08x\n",
+ __func__, start, size, parent->start,
+ parent->size);
+ return NULL;
+ }
+
+ /*
+ * We keep the list of child resources ordered which helps
+ * us searching for conflicts here.
+ */
+ list_for_each_entry(r, &parent->children, sibling) {
+ if (start + size <= r->start)
+ goto ok;
+ if (start >= r->start + r->size)
+ continue;
+ debug("%s: 0x%08x:0x%08x conflicts with 0x%08x:0x%08x\n",
+ __func__, start, size, r->start, r->size);
+ return NULL;
+ }
+
+ok:
+ debug("%s ok: 0x%08x 0x%08x\n", __func__, start, size);
+
+ new = xzalloc(sizeof(*new));
+ init_resource(new, name);
+ new->start = start;
+ new->size = size;
+ new->parent = parent;
+ list_add_tail(&new->sibling, &r->sibling);
+
+ return new;
+}
+
+/*
+ * release a region previously requested with request_region
+ */
+int release_region(struct resource *res)
+{
+ if (!list_empty(&res->children))
+ return -EBUSY;
+
+ list_del(&res->sibling);
+ free((char *)res->name);
+ free(res);
+
+ return 0;
+}
+
+/* The root resource for the whole io space */
+struct resource iomem_resource = {
+ .start = 0,
+ .size = ~0,
+};
+
+/*
+ * request a region inside the io space
+ */
+struct resource *request_iomem_region(const char *name,
+ resource_size_t start, resource_size_t size)
+{
+ return request_region(&iomem_resource, name, start, size);
+}
+
+static int iomem_init(void)
+{
+ init_resource(&iomem_resource, "iomem");
+
+ return 0;
+}
+postcore_initcall(iomem_init);
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 5143115..c837b53 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -20,6 +20,9 @@ struct resource {
resource_size_t size;
const char *name;
unsigned long flags;
+ struct resource *parent;
+ struct list_head children;
+ struct list_head sibling;
};
/*
@@ -111,5 +114,16 @@ static inline unsigned long resource_type(const struct resource *res)
return res->flags & IORESOURCE_TYPE_BITS;
}
+struct resource *request_iomem_region(const char *name,
+ resource_size_t start, resource_size_t size);
+
+struct resource *request_region(struct resource *parent,
+ const char *name, resource_size_t start,
+ resource_size_t size);
+
+int release_region(struct resource *res);
+
+extern struct resource iomem_resource;
+
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_IOPORT_H */