[PATCH 05/11] [PATCH] OMAP: hwmod: separate list locking and hwmod hardware locking
Paul Walmsley
paul at pwsan.com
Tue Sep 21 12:34:47 EDT 2010
From: Kevin Hilman <khilman at ti.com>
Currently omap_hwmod_mutex is being used to protect both the list
access/modification and concurrent access to hwmod functions. This
patch separates these two types of locking.
First, omap_hwmod_mutex is used only to protect access and
modification of omap_hwmod_list. Also cleaned up some comments
referring to this mutex that are no longer needed.
Then, for protecting concurrent access to hwmod functions, use a
per-hwmod mutex. This protects concurrent access to a single hwmod,
but would allow concurrent access to different hwmods.
Signed-off-by: Kevin Hilman <khilman at deeprootsystems.com>
[paul at pwsan.com: added structure documentation; changed mutex variable
name]
Signed-off-by: Paul Walmsley <paul at pwsan.com>
---
arch/arm/mach-omap2/omap_hwmod.c | 62 +++++++++++++-------------
arch/arm/plat-omap/include/plat/omap_hwmod.h | 3 +
2 files changed, 33 insertions(+), 32 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 100115f..3084409 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -767,10 +767,10 @@ static struct omap_hwmod *_lookup(const char *name)
* @data: not used; pass NULL
*
* Called by omap_hwmod_late_init() (after omap2_clk_init()).
- * Resolves all clock names embedded in the hwmod. Must be called
- * with omap_hwmod_mutex held. Returns -EINVAL if the omap_hwmod
- * has not yet been registered or if the clocks have already been
- * initialized, 0 on success, or a non-zero error on failure.
+ * Resolves all clock names embedded in the hwmod. Returns -EINVAL if
+ * the omap_hwmod has not yet been registered or if the clocks have
+ * already been initialized, 0 on success, or a non-zero error on
+ * failure.
*/
static int _init_clocks(struct omap_hwmod *oh, void *data)
{
@@ -838,10 +838,9 @@ static int _wait_target_ready(struct omap_hwmod *oh)
* @oh: struct omap_hwmod *
*
* Resets an omap_hwmod @oh via the OCP_SYSCONFIG bit. hwmod must be
- * enabled for this to work. Must be called with omap_hwmod_mutex
- * held. Returns -EINVAL if the hwmod cannot be reset this way or if
- * the hwmod is in the wrong state, -ETIMEDOUT if the module did not
- * reset in time, or 0 upon success.
+ * enabled for this to work. Returns -EINVAL if the hwmod cannot be
+ * reset this way or if the hwmod is in the wrong state, -ETIMEDOUT if
+ * the module did not reset in time, or 0 upon success.
*/
static int _reset(struct omap_hwmod *oh)
{
@@ -891,9 +890,8 @@ static int _reset(struct omap_hwmod *oh)
* @oh: struct omap_hwmod *
*
* Enables an omap_hwmod @oh such that the MPU can access the hwmod's
- * register target. Must be called with omap_hwmod_mutex held.
- * Returns -EINVAL if the hwmod is in the wrong state or passes along
- * the return value of _wait_target_ready().
+ * register target. Returns -EINVAL if the hwmod is in the wrong
+ * state or passes along the return value of _wait_target_ready().
*/
int _omap_hwmod_enable(struct omap_hwmod *oh)
{
@@ -1004,11 +1002,10 @@ static int _shutdown(struct omap_hwmod *oh)
* @skip_setup_idle_p: do not idle hwmods at the end of the fn if 1
*
* Writes the CLOCKACTIVITY bits @clockact to the hwmod @oh
- * OCP_SYSCONFIG register. Must be called with omap_hwmod_mutex held.
- * @skip_setup_idle is intended to be used on a system that will not
- * call omap_hwmod_enable() to enable devices (e.g., a system without
- * PM runtime). Returns -EINVAL if the hwmod is in the wrong state or
- * returns 0.
+ * OCP_SYSCONFIG register. @skip_setup_idle is intended to be used on
+ * a system that will not call omap_hwmod_enable() to enable devices
+ * (e.g., a system without PM runtime). Returns -EINVAL if the hwmod
+ * is in the wrong state or returns 0.
*/
static int _setup(struct omap_hwmod *oh, void *data)
{
@@ -1038,6 +1035,7 @@ static int _setup(struct omap_hwmod *oh, void *data)
}
}
+ mutex_init(&oh->_mutex);
oh->_state = _HWMOD_STATE_INITIALIZED;
r = _omap_hwmod_enable(oh);
@@ -1323,9 +1321,9 @@ int omap_hwmod_enable(struct omap_hwmod *oh)
if (!oh)
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
r = _omap_hwmod_enable(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return r;
}
@@ -1343,9 +1341,9 @@ int omap_hwmod_idle(struct omap_hwmod *oh)
if (!oh)
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_omap_hwmod_idle(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
@@ -1363,9 +1361,9 @@ int omap_hwmod_shutdown(struct omap_hwmod *oh)
if (!oh)
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_shutdown(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
@@ -1378,9 +1376,9 @@ int omap_hwmod_shutdown(struct omap_hwmod *oh)
*/
int omap_hwmod_enable_clocks(struct omap_hwmod *oh)
{
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_enable_clocks(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
@@ -1393,9 +1391,9 @@ int omap_hwmod_enable_clocks(struct omap_hwmod *oh)
*/
int omap_hwmod_disable_clocks(struct omap_hwmod *oh)
{
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_disable_clocks(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
@@ -1443,9 +1441,9 @@ int omap_hwmod_reset(struct omap_hwmod *oh)
if (!oh)
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
r = _reset(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return r;
}
@@ -1646,9 +1644,9 @@ int omap_hwmod_enable_wakeup(struct omap_hwmod *oh)
!(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_enable_wakeup(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
@@ -1671,9 +1669,9 @@ int omap_hwmod_disable_wakeup(struct omap_hwmod *oh)
!(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
return -EINVAL;
- mutex_lock(&omap_hwmod_mutex);
+ mutex_lock(&oh->_mutex);
_disable_wakeup(oh);
- mutex_unlock(&omap_hwmod_mutex);
+ mutex_unlock(&oh->_mutex);
return 0;
}
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index 5506d80..03350ba 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -35,6 +35,7 @@
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/ioport.h>
+#include <linux/mutex.h>
#include <plat/cpu.h>
struct omap_device;
@@ -433,6 +434,7 @@ struct omap_hwmod_class {
* @_state: internal-use hwmod state
* @flags: hwmod flags (documented below)
* @omap_chip: OMAP chips this hwmod is present on
+ * @_mutex: mutex serializing operations on this hwmod
* @node: list node for hwmod list (internal use)
*
* @main_clk refers to this module's "main clock," which for our
@@ -461,6 +463,7 @@ struct omap_hwmod {
void *dev_attr;
u32 _sysc_cache;
void __iomem *_mpu_rt_va;
+ struct mutex _mutex;
struct list_head node;
u16 flags;
u8 _mpu_port_index;
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