[PATCHv2 05/12] ARM: OMAP2+: hwmod: add setup_preprogram hook

Paul Walmsley paul at pwsan.com
Sun Jun 10 20:46:08 EDT 2012


After reset, some IP blocks cannot indicate to the PRCM that they are
inactive until they are configured.  Some examples on OMAP4 include
the AESS and FSUSB IP blocks.

To fix this cleanly, this patch adds another optional function
pointer, setup_preprogram, to the IP block's hwmod data.  The function
that is pointed to is called by the hwmod code immediately after the
IP block is reset.

Signed-off-by: Paul Walmsley <paul at pwsan.com>
Cc: Benoît Cousson <b-cousson at ti.com>
Cc: Péter Ujfalusi <peter.ujfalusi at ti.com>
Cc: Felipe Balbi <balbi at ti.com>
---
 arch/arm/mach-omap2/omap_hwmod.c             |   21 ++++++++++++++++++++-
 arch/arm/plat-omap/include/plat/omap_hwmod.h |    9 +++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 2d1111d..d27bf48 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2108,6 +2108,23 @@ static void __init _setup_iclk_autoidle(struct omap_hwmod *oh)
 }
 
 /**
+ * _setup_preprogram - Pre-program an IP block during the _setup() process
+ * @oh: struct omap_hwmod *
+ *
+ * Some IP blocks (such as AESS) require some additional programming
+ * after reset before they can enter idle.  If a function pointer to
+ * do so is present in the hwmod data, then call it and pass along the
+ * return value; otherwise, return 0.
+ */
+static int __init _setup_preprogram(struct omap_hwmod *oh)
+{
+	if (!oh->class->setup_preprogram)
+		return 0;
+
+	return oh->class->setup_preprogram(oh);
+}
+
+/**
  * _setup_reset - reset an IP block during the setup process
  * @oh: struct omap_hwmod *
  *
@@ -2229,8 +2246,10 @@ static int __init _setup(struct omap_hwmod *oh, void *data)
 
 	_setup_iclk_autoidle(oh);
 
-	if (!_setup_reset(oh))
+	if (!_setup_reset(oh)) {
+		_setup_preprogram(oh);
 		_setup_postsetup(oh);
+	}
 
 	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 038c0d7..2c53648 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -467,6 +467,7 @@ struct omap_hwmod_omap4_prcm {
  * @rev: revision of the IP class
  * @pre_shutdown: ptr to fn to be executed immediately prior to device shutdown
  * @reset: ptr to fn to be executed in place of the standard hwmod reset fn
+ * @setup_preprogram: ptr to fn to be executed after the reset in _setup()
  *
  * Represent the class of a OMAP hardware "modules" (e.g. timer,
  * smartreflex, gpio, uart...)
@@ -483,6 +484,13 @@ struct omap_hwmod_omap4_prcm {
  * executed in place of the standard hwmod _reset() code in
  * mach-omap2/omap_hwmod.c.  This is needed for IP blocks which have
  * unusual reset sequences - usually processor IP blocks like the IVA.
+ *
+ * @setup_preprogram is called between the calls to _setup_reset() and
+ * _setup_postsetup().  It is intended to be used for IP blocks that
+ * require some initial configuration during their first
+ * initialization.  (For example, the AESS IP block on OMAP4+ cannot
+ * enter idle until its internal autogating bit is set.)  Most IP blocks
+ * will not need this.
  */
 struct omap_hwmod_class {
 	const char				*name;
@@ -490,6 +498,7 @@ struct omap_hwmod_class {
 	u32					rev;
 	int					(*pre_shutdown)(struct omap_hwmod *oh);
 	int					(*reset)(struct omap_hwmod *oh);
+	int					(*setup_preprogram)(struct omap_hwmod *oh);
 };
 
 /**





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