Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 108 insertions, 46 deletions

diff --git a/kernel/resource.c b/kernel/resource.c
index 09c0597840b0..2e78ead30934 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -233,9 +233,9 @@ static struct resource * __request_resource(struct resource *root, struct resour
 	}
 }
 
-static int __release_resource(struct resource *old)
+static int __release_resource(struct resource *old, bool release_child)
 {
-	struct resource *tmp, **p;
+	struct resource *tmp, **p, *chd;
 
 	p = &old->parent->child;
 	for (;;) {
@@ -243,7 +243,17 @@ static int __release_resource(struct resource *old)
 		if (!tmp)
 			break;
 		if (tmp == old) {
-			*p = tmp->sibling;
+			if (release_child || !(tmp->child)) {
+				*p = tmp->sibling;
+			} else {
+				for (chd = tmp->child;; chd = chd->sibling) {
+					chd->parent = tmp->parent;
+					if (!(chd->sibling))
+						break;
+				}
+				*p = tmp->child;
+				chd->sibling = tmp->sibling;
+			}
 			old->parent = NULL;
 			return 0;
 		}
@@ -325,7 +335,7 @@ int release_resource(struct resource *old)
 	int retval;
 
 	write_lock(&resource_lock);
-	retval = __release_resource(old);
+	retval = __release_resource(old, true);
 	write_unlock(&resource_lock);
 	return retval;
 }
@@ -333,13 +343,13 @@ int release_resource(struct resource *old)
 EXPORT_SYMBOL(release_resource);
 
 /*
- * Finds the lowest iomem reosurce exists with-in [res->start.res->end)
- * the caller must specify res->start, res->end, res->flags and "name".
- * If found, returns 0, res is overwritten, if not found, returns -1.
- * This walks through whole tree and not just first level children
- * until and unless first_level_children_only is true.
+ * Finds the lowest iomem resource existing within [res->start.res->end).
+ * The caller must specify res->start, res->end, res->flags, and optionally
+ * desc.  If found, returns 0, res is overwritten, if not found, returns -1.
+ * This function walks the whole tree and not just first level children until
+ * and unless first_level_children_only is true.
  */
-static int find_next_iomem_res(struct resource *res, char *name,
+static int find_next_iomem_res(struct resource *res, unsigned long desc,
 			       bool first_level_children_only)
 {
 	resource_size_t start, end;
@@ -358,9 +368,9 @@ static int find_next_iomem_res(struct resource *res, char *name,
 	read_lock(&resource_lock);
 
 	for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
-		if (p->flags != res->flags)
+		if ((p->flags & res->flags) != res->flags)
 			continue;
-		if (name && strcmp(p->name, name))
+		if ((desc != IORES_DESC_NONE) && (desc != p->desc))
 			continue;
 		if (p->start > end) {
 			p = NULL;
@@ -385,15 +395,18 @@ static int find_next_iomem_res(struct resource *res, char *name,
  * Walks through iomem resources and calls func() with matching resource
  * ranges. This walks through whole tree and not just first level children.
  * All the memory ranges which overlap start,end and also match flags and
- * name are valid candidates.
+ * desc are valid candidates.
  *
- * @name: name of resource
- * @flags: resource flags
+ * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
+ * @flags: I/O resource flags
  * @start: start addr
  * @end: end addr
+ *
+ * NOTE: For a new descriptor search, define a new IORES_DESC in
+ * <linux/ioport.h> and set it in 'desc' of a target resource entry.
  */
-int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end,
-		void *arg, int (*func)(u64, u64, void *))
+int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start,
+		u64 end, void *arg, int (*func)(u64, u64, void *))
 {
 	struct resource res;
 	u64 orig_end;
@@ -403,23 +416,27 @@ int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end,
 	res.end = end;
 	res.flags = flags;
 	orig_end = res.end;
+
 	while ((res.start < res.end) &&
-		(!find_next_iomem_res(&res, name, false))) {
+		(!find_next_iomem_res(&res, desc, false))) {
+
 		ret = (*func)(res.start, res.end, arg);
 		if (ret)
 			break;
+
 		res.start = res.end + 1;
 		res.end = orig_end;
 	}
+
 	return ret;
 }
 
 /*
- * This function calls callback against all memory range of "System RAM"
- * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
- * Now, this function is only for "System RAM". This function deals with
- * full ranges and not pfn. If resources are not pfn aligned, dealing
- * with pfn can truncate ranges.
+ * This function calls the @func callback against all memory ranges of type
+ * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
+ * Now, this function is only for System RAM, it deals with full ranges and
+ * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate
+ * ranges.
  */
 int walk_system_ram_res(u64 start, u64 end, void *arg,
 				int (*func)(u64, u64, void *))
@@ -430,10 +447,10 @@ int walk_system_ram_res(u64 start, u64 end, void *arg,
 
 	res.start = start;
 	res.end = end;
-	res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+	res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 	orig_end = res.end;
 	while ((res.start < res.end) &&
-		(!find_next_iomem_res(&res, "System RAM", true))) {
+		(!find_next_iomem_res(&res, IORES_DESC_NONE, true))) {
 		ret = (*func)(res.start, res.end, arg);
 		if (ret)
 			break;
@@ -446,9 +463,9 @@ int walk_system_ram_res(u64 start, u64 end, void *arg,
 #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
 
 /*
- * This function calls callback against all memory range of "System RAM"
- * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
- * Now, this function is only for "System RAM".
+ * This function calls the @func callback against all memory ranges of type
+ * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
+ * It is to be used only for System RAM.
  */
 int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
 		void *arg, int (*func)(unsigned long, unsigned long, void *))
@@ -460,10 +477,10 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
 
 	res.start = (u64) start_pfn << PAGE_SHIFT;
 	res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
-	res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+	res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 	orig_end = res.end;
 	while ((res.start < res.end) &&
-		(find_next_iomem_res(&res, "System RAM", true) >= 0)) {
+		(find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) {
 		pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
 		end_pfn = (res.end + 1) >> PAGE_SHIFT;
 		if (end_pfn > pfn)
@@ -484,7 +501,7 @@ static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
 }
 /*
  * This generic page_is_ram() returns true if specified address is
- * registered as "System RAM" in iomem_resource list.
+ * registered as System RAM in iomem_resource list.
  */
 int __weak page_is_ram(unsigned long pfn)
 {
@@ -496,30 +513,34 @@ EXPORT_SYMBOL_GPL(page_is_ram);
  * region_intersects() - determine intersection of region with known resources
  * @start: region start address
  * @size: size of region
- * @name: name of resource (in iomem_resource)
+ * @flags: flags of resource (in iomem_resource)
+ * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
  *
  * Check if the specified region partially overlaps or fully eclipses a
- * resource identified by @name.  Return REGION_DISJOINT if the region
- * does not overlap @name, return REGION_MIXED if the region overlaps
- * @type and another resource, and return REGION_INTERSECTS if the
- * region overlaps @type and no other defined resource. Note, that
- * REGION_INTERSECTS is also returned in the case when the specified
- * region overlaps RAM and undefined memory holes.
+ * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
+ * Return REGION_DISJOINT if the region does not overlap @flags/@desc,
+ * return REGION_MIXED if the region overlaps @flags/@desc and another
+ * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
+ * and no other defined resource. Note that REGION_INTERSECTS is also
+ * returned in the case when the specified region overlaps RAM and undefined
+ * memory holes.
  *
  * region_intersect() is used by memory remapping functions to ensure
  * the user is not remapping RAM and is a vast speed up over walking
  * through the resource table page by page.
  */
-int region_intersects(resource_size_t start, size_t size, const char *name)
+int region_intersects(resource_size_t start, size_t size, unsigned long flags,
+		      unsigned long desc)
 {
-	unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 	resource_size_t end = start + size - 1;
 	int type = 0; int other = 0;
 	struct resource *p;
 
 	read_lock(&resource_lock);
 	for (p = iomem_resource.child; p ; p = p->sibling) {
-		bool is_type = strcmp(p->name, name) == 0 && p->flags == flags;
+		bool is_type = (((p->flags & flags) == flags) &&
+				((desc == IORES_DESC_NONE) ||
+				 (desc == p->desc)));
 
 		if (start >= p->start && start <= p->end)
 			is_type ? type++ : other++;
@@ -538,6 +559,7 @@ int region_intersects(resource_size_t start, size_t size, const char *name)
 
 	return REGION_DISJOINT;
 }
+EXPORT_SYMBOL_GPL(region_intersects);
 
 void __weak arch_remove_reservations(struct resource *avail)
 {
@@ -667,7 +689,7 @@ static int reallocate_resource(struct resource *root, struct resource *old,
 		old->start = new.start;
 		old->end = new.end;
 	} else {
-		__release_resource(old);
+		__release_resource(old, true);
 		*old = new;
 		conflict = __request_resource(root, old);
 		BUG_ON(conflict);
@@ -813,6 +835,9 @@ static struct resource * __insert_resource(struct resource *parent, struct resou
  * entirely fit within the range of the new resource, then the new
  * resource is inserted and the conflicting resources become children of
  * the new resource.
+ *
+ * This function is intended for producers of resources, such as FW modules
+ * and bus drivers.
  */
 struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
 {
@@ -830,6 +855,9 @@ struct resource *insert_resource_conflict(struct resource *parent, struct resour
  * @new: new resource to insert
  *
  * Returns 0 on success, -EBUSY if the resource can't be inserted.
+ *
+ * This function is intended for producers of resources, such as FW modules
+ * and bus drivers.
  */
 int insert_resource(struct resource *parent, struct resource *new)
 {
@@ -838,6 +866,7 @@ int insert_resource(struct resource *parent, struct resource *new)
 	conflict = insert_resource_conflict(parent, new);
 	return conflict ? -EBUSY : 0;
 }
+EXPORT_SYMBOL_GPL(insert_resource);
 
 /**
  * insert_resource_expand_to_fit - Insert a resource into the resource tree
@@ -873,6 +902,32 @@ void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
 	write_unlock(&resource_lock);
 }
 
+/**
+ * remove_resource - Remove a resource in the resource tree
+ * @old: resource to remove
+ *
+ * Returns 0 on success, -EINVAL if the resource is not valid.
+ *
+ * This function removes a resource previously inserted by insert_resource()
+ * or insert_resource_conflict(), and moves the children (if any) up to
+ * where they were before.  insert_resource() and insert_resource_conflict()
+ * insert a new resource, and move any conflicting resources down to the
+ * children of the new resource.
+ *
+ * insert_resource(), insert_resource_conflict() and remove_resource() are
+ * intended for producers of resources, such as FW modules and bus drivers.
+ */
+int remove_resource(struct resource *old)
+{
+	int retval;
+
+	write_lock(&resource_lock);
+	retval = __release_resource(old, false);
+	write_unlock(&resource_lock);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(remove_resource);
+
 static int __adjust_resource(struct resource *res, resource_size_t start,
 				resource_size_t size)
 {
@@ -948,6 +1003,7 @@ static void __init __reserve_region_with_split(struct resource *root,
 	res->start = start;
 	res->end = end;
 	res->flags = IORESOURCE_BUSY;
+	res->desc = IORES_DESC_NONE;
 
 	while (1) {
 
@@ -982,6 +1038,7 @@ static void __init __reserve_region_with_split(struct resource *root,
 				next_res->start = conflict->end + 1;
 				next_res->end = end;
 				next_res->flags = IORESOURCE_BUSY;
+				next_res->desc = IORES_DESC_NONE;
 			}
 		} else {
 			res->start = conflict->end + 1;
@@ -1071,21 +1128,24 @@ struct resource * __request_region(struct resource *parent,
 	res->name = name;
 	res->start = start;
 	res->end = start + n - 1;
-	res->flags = resource_type(parent);
-	res->flags |= IORESOURCE_BUSY | flags;
 
 	write_lock(&resource_lock);
 
 	for (;;) {
 		struct resource *conflict;
 
+		res->flags = resource_type(parent) | resource_ext_type(parent);
+		res->flags |= IORESOURCE_BUSY | flags;
+		res->desc = parent->desc;
+
 		conflict = __request_resource(parent, res);
 		if (!conflict)
 			break;
 		if (conflict != parent) {
-			parent = conflict;
-			if (!(conflict->flags & IORESOURCE_BUSY))
+			if (!(conflict->flags & IORESOURCE_BUSY)) {
+				parent = conflict;
 				continue;
+			}
 		}
 		if (conflict->flags & flags & IORESOURCE_MUXED) {
 			add_wait_queue(&muxed_resource_wait, &wait);
@@ -1237,6 +1297,7 @@ int release_mem_region_adjustable(struct resource *parent,
 			new_res->start = end + 1;
 			new_res->end = res->end;
 			new_res->flags = res->flags;
+			new_res->desc = res->desc;
 			new_res->parent = res->parent;
 			new_res->sibling = res->sibling;
 			new_res->child = NULL;
@@ -1412,6 +1473,7 @@ static int __init reserve_setup(char *str)
 			res->start = io_start;
 			res->end = io_start + io_num - 1;
 			res->flags = IORESOURCE_BUSY;
+			res->desc = IORES_DESC_NONE;
 			res->child = NULL;
 			if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
 				reserved = x+1;