[PATCH 2/6] ARM: OMAP2+: hwmod: use init-time function ptrs for enable/disable module

Paul Walmsley paul at pwsan.com
Mon Apr 30 10:28:51 EDT 2012


Hi Kevin,

On Fri, 27 Apr 2012, Kevin Hilman wrote:

> The enable/disable module functions are specific to SoCs with
> OMAP4-class PRCM.  Rather than use cpu_is* checks at runtime inside
> the enable/disable module functions, use cpu_is at init time to
> initialize function pointers only for SoCs that need them.
> 
> NOTE: the cpu_is* check for _enable_module was different than
>       the one for _disable_module, and this patch uses
>       cpu_is_omap44xx() for both.
> 
> Signed-off-by: Kevin Hilman <khilman at ti.com>

Since these function pointers are common to all of the hwmods on the 
currently-booted SoC, they've been moved off into a separate structure, 
used by a file static variable (for omap_hwmod.c).  This should conserve 
some memory and cache.  Also moved the initialization of these pointers 
off to an init function that is called once during kernel init, before any 
hwmods are registered.  Please let me know if you have any comments.


- Paul

From: Kevin Hilman <khilman at ti.com>
Date: Fri, 27 Apr 2012 13:05:36 -0700
Subject: [PATCH 2/6] ARM: OMAP2+: hwmod: use init-time function ptrs for
 enable/disable module

The enable/disable module functions are specific to SoCs with
OMAP4-class PRCM.  Rather than use cpu_is* checks at runtime inside
the enable/disable module functions, use cpu_is at init time to
initialize function pointers only for SoCs that need them.

NOTE: the cpu_is* check for _enable_module was different than
      the one for _disable_module, and this patch uses
      cpu_is_omap44xx() for both.

Signed-off-by: Kevin Hilman <khilman at ti.com>
[paul at pwsan.com: moved soc_ops function pointers to be per-kernel rather than
 per-hwmod since they do not vary by hwmod; added kerneldoc]
Signed-off-by: Paul Walmsley <paul at pwsan.com>
---
 arch/arm/mach-omap2/omap_hwmod.c             |   62 +++++++++++++++++++++-----
 arch/arm/mach-omap2/omap_hwmod_2420_data.c   |    1 +
 arch/arm/mach-omap2/omap_hwmod_2430_data.c   |    1 +
 arch/arm/mach-omap2/omap_hwmod_3xxx_data.c   |    2 +
 arch/arm/mach-omap2/omap_hwmod_44xx_data.c   |    1 +
 arch/arm/plat-omap/include/plat/omap_hwmod.h |    2 +
 6 files changed, 57 insertions(+), 12 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 939032a..634a798 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -166,6 +166,23 @@
  */
 #define LINKS_PER_OCP_IF		2
 
+/**
+ * struct omap_hwmod_soc_ops - fn ptrs for some SoC-specific operations
+ * @enable_module: function to enable a module (via MODULEMODE)
+ * @disable_module: function to disable a module (via MODULEMODE)
+ *
+ * XXX Eventually this functionality will be hidden inside the PRM/CM
+ * device drivers.  Until then, this should avoid huge blocks of cpu_is_*()
+ * conditionals in this code.
+ */
+struct omap_hwmod_soc_ops {
+	void (*enable_module)(struct omap_hwmod *oh);
+	int (*disable_module)(struct omap_hwmod *oh);
+};
+
+/* soc_ops: adapts the omap_hwmod code to the currently-booted SoC */
+static struct omap_hwmod_soc_ops soc_ops;
+
 /* omap_hwmod_list contains all registered struct omap_hwmods */
 static LIST_HEAD(omap_hwmod_list);
 
@@ -186,6 +203,9 @@ static struct omap_hwmod_link *linkspace;
  */
 static unsigned short free_ls, max_ls, ls_supp;
 
+/* inited: set to true once the hwmod code is initialized */
+static bool inited;
+
 /* Private functions */
 
 /**
@@ -779,10 +799,6 @@ static void _disable_optional_clocks(struct omap_hwmod *oh)
  */
 static void _omap4_enable_module(struct omap_hwmod *oh)
 {
-	/* The module mode does not exist prior OMAP4 */
-	if (cpu_is_omap24xx() || cpu_is_omap34xx())
-		return;
-
 	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
 		return;
 
@@ -1571,10 +1587,6 @@ static int _omap4_disable_module(struct omap_hwmod *oh)
 {
 	int v;
 
-	/* The module mode does not exist prior OMAP4 */
-	if (!cpu_is_omap44xx())
-		return -EINVAL;
-
 	if (!oh->clkdm || !oh->prcm.omap4.modulemode)
 		return -EINVAL;
 
@@ -1814,7 +1826,8 @@ static int _enable(struct omap_hwmod *oh)
 	}
 
 	_enable_clocks(oh);
-	_omap4_enable_module(oh);
+	if (soc_ops.enable_module)
+		soc_ops.enable_module(oh);
 
 	r = _wait_target_ready(oh);
 	if (!r) {
@@ -1870,7 +1883,8 @@ static int _idle(struct omap_hwmod *oh)
 		_idle_sysc(oh);
 	_del_initiator_dep(oh, mpu_oh);
 
-	_omap4_disable_module(oh);
+	if (soc_ops.disable_module)
+		soc_ops.disable_module(oh);
 
 	/*
 	 * The module must be in idle mode before disabling any parents
@@ -1975,7 +1989,8 @@ static int _shutdown(struct omap_hwmod *oh)
 	if (oh->_state == _HWMOD_STATE_ENABLED) {
 		_del_initiator_dep(oh, mpu_oh);
 		/* XXX what about the other system initiators here? dma, dsp */
-		_omap4_disable_module(oh);
+		if (soc_ops.disable_module)
+			soc_ops.disable_module(oh);
 		_disable_clocks(oh);
 		if (oh->clkdm)
 			clkdm_hwmod_disable(oh->clkdm, oh);
@@ -2563,12 +2578,18 @@ int omap_hwmod_for_each(int (*fn)(struct omap_hwmod *oh, void *data),
  *
  * Intended to be called early in boot before the clock framework is
  * initialized.  If @ois is not null, will register all omap_hwmods
- * listed in @ois that are valid for this chip.  Returns 0.
+ * listed in @ois that are valid for this chip.  Returns -EINVAL if
+ * omap_hwmod_init() hasn't been called before calling this function,
+ * -ENOMEM if the link memory area can't be allocated, or 0 upon
+ * success.
  */
 int __init omap_hwmod_register_links(struct omap_hwmod_ocp_if **ois)
 {
 	int r, i;
 
+	if (!inited)
+		return -EINVAL;
+
 	if (!ois)
 		return 0;
 
@@ -3401,3 +3422,20 @@ int omap_hwmod_pad_route_irq(struct omap_hwmod *oh, int pad_idx, int irq_idx)
 
 	return 0;
 }
+
+/**
+ * omap_hwmod_init - initialize the hwmod code
+ *
+ * Sets up some function pointers needed by the hwmod code to operate on the
+ * currently-booted SoC.  Intended to be called once during kernel init
+ * before any hwmods are registered.  No return value.
+ */
+void __init omap_hwmod_init(void)
+{
+	if (cpu_is_omap44xx()) {
+		soc_ops.enable_module = _omap4_enable_module;
+		soc_ops.disable_module = _omap4_disable_module;
+	}
+
+	inited = true;
+}
diff --git a/arch/arm/mach-omap2/omap_hwmod_2420_data.c b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
index 2c087ff..f30a219 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2420_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2420_data.c
@@ -473,5 +473,6 @@ static struct omap_hwmod_ocp_if *omap2420_hwmod_ocp_ifs[] __initdata = {
 
 int __init omap2420_hwmod_init(void)
 {
+	omap_hwmod_init();
 	return omap_hwmod_register_links(omap2420_hwmod_ocp_ifs);
 }
diff --git a/arch/arm/mach-omap2/omap_hwmod_2430_data.c b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
index 71d9f88..2e561ff 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2430_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
@@ -891,5 +891,6 @@ static struct omap_hwmod_ocp_if *omap2430_hwmod_ocp_ifs[] __initdata = {
 
 int __init omap2430_hwmod_init(void)
 {
+	omap_hwmod_init();
 	return omap_hwmod_register_links(omap2430_hwmod_ocp_ifs);
 }
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 0c65079..34fc5bd 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -3201,6 +3201,8 @@ int __init omap3xxx_hwmod_init(void)
 	struct omap_hwmod_ocp_if **h = NULL;
 	unsigned int rev;
 
+	omap_hwmod_init();
+
 	/* Register hwmod links common to all OMAP3 */
 	r = omap_hwmod_register_links(omap3xxx_hwmod_ocp_ifs);
 	if (r < 0)
diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index 0d91dec..4b436b7 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -4796,6 +4796,7 @@ static struct omap_hwmod_ocp_if *omap44xx_hwmod_ocp_ifs[] __initdata = {
 
 int __init omap44xx_hwmod_init(void)
 {
+	omap_hwmod_init();
 	return omap_hwmod_register_links(omap44xx_hwmod_ocp_ifs);
 }
 
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index 14dde32..d2f3ee4 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -628,6 +628,8 @@ int omap_hwmod_no_setup_reset(struct omap_hwmod *oh);
 
 int omap_hwmod_pad_route_irq(struct omap_hwmod *oh, int pad_idx, int irq_idx);
 
+extern void __init omap_hwmod_init(void);
+
 /*
  * Chip variant-specific hwmod init routines - XXX should be converted
  * to use initcalls once the initial boot ordering is straightened out
-- 
1.7.10




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