This patch fills in the OCP_SYSCONFIG.AUTOIDLE handling in the OMAP
hwmod code.
After this patch, the hwmod code will set the module AUTOIDLE bit
(generally <module>.OCP_SYSCONFIG.AUTOIDLE) to 1 by default upon
enable. If the hwmod flag HWMOD_NO_OCP_AUTOIDLE is set, AUTOIDLE will
be set to 0 upon enable. Upon module disable, AUTOIDLE will be set to
1.
Enabling module autoidle should save some power. The only reason to
not set the OCP_SYSCONFIG.AUTOIDLE bit is if there is a bug in the
module RTL, e.g., the MPUINTC block on OMAP3.
Comments from Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> inspired this patch,
and Kevin tested an earlier version of this patch.
Signed-off-by: Paul Walmsley <paul@xxxxxxxxx>
Tested-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-omap2/omap_hwmod.c | 37 +++++++++++++++++++++++++-
arch/arm/plat-omap/include/plat/omap_hwmod.h | 8 +++++-
2 files changed, 42 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 4aab1b8..709ec5d 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -210,6 +210,32 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v)
}
/**
+ * _set_module_autoidle: set the OCP_SYSCONFIG AUTOIDLE field in @v
+ * @oh: struct omap_hwmod *
+ * @autoidle: desired AUTOIDLE bitfield value (0 or 1)
+ * @v: pointer to register contents to modify
+ *
+ * Update the module autoidle bit in @v to be @autoidle for the @oh
+ * hwmod. The autoidle bit controls whether the module can gate
+ * internal clocks automatically when it isn't doing anything; the
+ * exact function of this bit varies on a per-module basis. This
+ * function does not write to the hardware. Returns -EINVAL upon
+ * error or 0 upon success.
+ */
+static int _set_module_autoidle(struct omap_hwmod *oh, u8 autoidle,
+ u32 *v)
+{
+ if (!oh->sysconfig ||
+ !(oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE))
+ return -EINVAL;
+
+ *v &= ~SYSC_AUTOIDLE_MASK;
+ *v |= autoidle << SYSC_AUTOIDLE_SHIFT;
+
+ return 0;
+}
+
+/**
* _enable_wakeup: set OCP_SYSCONFIG.ENAWAKEUP bit in the hardware
* @oh: struct omap_hwmod *
*
@@ -557,7 +583,13 @@ static void _sysc_enable(struct omap_hwmod *oh)
_set_master_standbymode(oh, idlemode, &v);
}
- /* XXX OCP AUTOIDLE bit? */
+ if (oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE) {
+ idlemode = (oh->flags & HWMOD_NO_OCP_AUTOIDLE) ?
+ 0 : 1;
+ _set_module_autoidle(oh, idlemode, &v);
+ }
+
+ /* XXX OCP ENAWAKEUP bit? */
if (oh->flags & HWMOD_SET_DEFAULT_CLOCKACT &&
oh->sysconfig->sysc_flags & SYSC_HAS_CLOCKACTIVITY)
@@ -622,7 +654,8 @@ static void _sysc_shutdown(struct omap_hwmod *oh)
if (oh->sysconfig->sysc_flags & SYSC_HAS_MIDLEMODE)
_set_master_standbymode(oh, HWMOD_IDLEMODE_FORCE, &v);
- /* XXX clear OCP AUTOIDLE bit? */
+ if (oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE)
+ _set_module_autoidle(oh, 1, &v);
_write_sysconfig(v, oh);
}
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index dbdd123..643a972 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -50,6 +50,8 @@ struct omap_device;
#define SYSC_ENAWAKEUP_MASK (1 << SYSC_ENAWAKEUP_SHIFT)
#define SYSC_SOFTRESET_SHIFT 1
#define SYSC_SOFTRESET_MASK (1 << SYSC_SOFTRESET_SHIFT)
+#define SYSC_AUTOIDLE_SHIFT 0
+#define SYSC_AUTOIDLE_MASK (1 << SYSC_AUTOIDLE_SHIFT)
/* OCP SYSSTATUS bit shifts/masks */
#define SYSS_RESETDONE_SHIFT 0
@@ -294,13 +296,17 @@ struct omap_hwmod_omap4_prcm {
* SDRAM controller, etc.
* HWMOD_INIT_NO_IDLE: don't idle this module at boot - important for SDRAM
* controller, etc.
+ * HWMOD_NO_AUTOIDLE: disable module autoidle (OCP_SYSCONFIG.AUTOIDLE)
+ * when module is enabled, rather than the default, which is to
+ * enable autoidle
* HWMOD_SET_DEFAULT_CLOCKACT: program CLOCKACTIVITY bits at startup
*/
#define HWMOD_SWSUP_SIDLE (1 << 0)
#define HWMOD_SWSUP_MSTANDBY (1 << 1)
#define HWMOD_INIT_NO_RESET (1 << 2)
#define HWMOD_INIT_NO_IDLE (1 << 3)
-#define HWMOD_SET_DEFAULT_CLOCKACT (1 << 4)
+#define HWMOD_NO_OCP_AUTOIDLE (1 << 4)
+#define HWMOD_SET_DEFAULT_CLOCKACT (1 << 5)
/*
* omap_hwmod._int_flags definitions
--
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