[PATCH 4.2.y-ckt 71/98] ARM: OMAP2+: hwmod: Introduce ti,no-idle dt property

From: Kamal Mostafa
Date: Tue Mar 15 2016 - 19:42:44 EST


4.2.8-ckt6 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Lokesh Vutla <lokeshvutla@xxxxxx>

commit 2e18f5a1bc18e8af7031b3b26efde25307014837 upstream.

Introduce a dt property, ti,no-idle, that prevents an IP to idle at any
point. This is to handle Errata i877, which tells that GMAC clocks
cannot be disabled.

Acked-by: Roger Quadros <rogerq@xxxxxx>
Tested-by: Mugunthan V N <mugunthanvnm@xxxxxx>
Signed-off-by: Lokesh Vutla <lokeshvutla@xxxxxx>
Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>
Signed-off-by: Dave Gerlach <d-gerlach@xxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Paul Walmsley <paul@xxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/arm/omap/omap.txt | 1 +
arch/arm/mach-omap2/omap_hwmod.c | 9 ++++++++-
arch/arm/mach-omap2/omap_hwmod.h | 3 +++
3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/omap/omap.txt b/Documentation/devicetree/bindings/arm/omap/omap.txt
index 4f6a82c..cbe35b3 100644
--- a/Documentation/devicetree/bindings/arm/omap/omap.txt
+++ b/Documentation/devicetree/bindings/arm/omap/omap.txt
@@ -23,6 +23,7 @@ Optional properties:
during suspend.
- ti,no-reset-on-init: When present, the module should not be reset at init
- ti,no-idle-on-init: When present, the module should not be idled at init
+- ti,no-idle: When present, the module is never allowed to idle.

Example:

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 486cc4d..573da0d 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2180,6 +2180,11 @@ static int _enable(struct omap_hwmod *oh)
*/
static int _idle(struct omap_hwmod *oh)
{
+ if (oh->flags & HWMOD_NO_IDLE) {
+ oh->_int_flags |= _HWMOD_SKIP_ENABLE;
+ return 0;
+ }
+
pr_debug("omap_hwmod: %s: idling\n", oh->name);

if (oh->_state != _HWMOD_STATE_ENABLED) {
@@ -2484,6 +2489,8 @@ static int __init _init(struct omap_hwmod *oh, void *data)
oh->flags |= HWMOD_INIT_NO_RESET;
if (of_find_property(np, "ti,no-idle-on-init", NULL))
oh->flags |= HWMOD_INIT_NO_IDLE;
+ if (of_find_property(np, "ti,no-idle", NULL))
+ oh->flags |= HWMOD_NO_IDLE;
}

oh->_state = _HWMOD_STATE_INITIALIZED;
@@ -2610,7 +2617,7 @@ static void __init _setup_postsetup(struct omap_hwmod *oh)
* XXX HWMOD_INIT_NO_IDLE does not belong in hwmod data -
* it should be set by the core code as a runtime flag during startup
*/
- if ((oh->flags & HWMOD_INIT_NO_IDLE) &&
+ if ((oh->flags & (HWMOD_INIT_NO_IDLE | HWMOD_NO_IDLE)) &&
(postsetup_state == _HWMOD_STATE_IDLE)) {
oh->_int_flags |= _HWMOD_SKIP_ENABLE;
postsetup_state = _HWMOD_STATE_ENABLED;
diff --git a/arch/arm/mach-omap2/omap_hwmod.h b/arch/arm/mach-omap2/omap_hwmod.h
index b5d27ec..1681310 100644
--- a/arch/arm/mach-omap2/omap_hwmod.h
+++ b/arch/arm/mach-omap2/omap_hwmod.h
@@ -523,6 +523,8 @@ struct omap_hwmod_omap4_prcm {
* HWMOD_RECONFIG_IO_CHAIN: omap_hwmod code needs to reconfigure wake-up
* events by calling _reconfigure_io_chain() when a device is enabled
* or idled.
+ * HWMOD_NO_IDLE: Do not idle the hwmod at all. Useful to handle certain
+ * IPs like CPSW on DRA7, where clocks to this module cannot be disabled.
*/
#define HWMOD_SWSUP_SIDLE (1 << 0)
#define HWMOD_SWSUP_MSTANDBY (1 << 1)
@@ -538,6 +540,7 @@ struct omap_hwmod_omap4_prcm {
#define HWMOD_FORCE_MSTANDBY (1 << 11)
#define HWMOD_SWSUP_SIDLE_ACT (1 << 12)
#define HWMOD_RECONFIG_IO_CHAIN (1 << 13)
+#define HWMOD_NO_IDLE (1 << 15)

/*
* omap_hwmod._int_flags definitions
--
2.7.0