[PATCH 0/5] clk: bcm: prerequisite and bus clock support

[PATCH 0/5] clk: bcm: prerequisite and bus clock support

[Alex Elder]

Currently only peripheral clocks are supported for Broadcom
platforms that use Kona style CCUs for clocking.  This series
adds support for bus clocks as well.

One motivation for doing this is that there exist peripheral clocks
that cannot be configured without having first enabled a related
bus; the peripheral clock registers are simply inaccessible if the
bus clock is not enabled.  So adding bus clock support allows such
clocks to be usable.

This also imposes a new requirement, however--that the bus clock
be enabled *before* the clock that depends on it.  For this, we
define the notion of a "prerequisite" clock.  If a clock has a
prerequisite specified, that prequisite clock will be initialized
first.  For now this only affects startup-time initialization.

These patches are based on Mike Turquette's current "clk-next"
branch.  They are available here:
    http://git.linaro.org/landing-teams/working/broadcom/kernel.git
    Branch review/bcm-bus-clk

					-Alex

Alex Elder (5):
  clk: bcm281xx: add an initialized flag
  clk: bcm281xx: implement prerequisite clocks
  clk: bcm281xx: add bus clock support
  clk: bcm281xx: define a bus clock
  ARM: dts: add bus clock bsc3_apb for bcm281xx

 arch/arm/boot/dts/bcm11351.dtsi      |   3 +-
 drivers/clk/bcm/clk-bcm281xx.c       |  13 +++-
 drivers/clk/bcm/clk-kona-setup.c     | 112 ++++++++++++++++++++++++++++++--
 drivers/clk/bcm/clk-kona.c           | 120 ++++++++++++++++++++++++++++++++++-
 drivers/clk/bcm/clk-kona.h           |  35 +++++++++-
 include/dt-bindings/clock/bcm281xx.h |   3 +-
 6 files changed, 271 insertions(+), 15 deletions(-)

-- 
1.9.1

[PATCH 1/5] clk: bcm281xx: add an initialized flag

[Alex Elder]

Add a flag that tracks whether a clock has already been initialized.
This will be used by the next patch to avoid initializing a clock
more than once when it's listed as a prerequisite.

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/clk/bcm/clk-kona.c | 17 +++++++++++++++--
 drivers/clk/bcm/clk-kona.h |  7 +++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/bcm/clk-kona.c b/drivers/clk/bcm/clk-kona.c
index d603c4e..d8a7f38 100644
--- a/drivers/clk/bcm/clk-kona.c
+++ b/drivers/clk/bcm/clk-kona.c
@@ -27,6 +27,9 @@
 #define CCU_ACCESS_PASSWORD      0xA5A500
 #define CLK_GATE_DELAY_LOOP      2000
 
+#define clk_is_initialized(_clk)	FLAG_TEST((_clk), KONA, INITIALIZED)
+#define clk_set_initialized(_clk)	FLAG_SET((_clk), KONA, INITIALIZED)
+
 /* Bitfield operations */
 
 /* Produces a mask of set bits covering a range of a 32-bit value */
@@ -1194,13 +1197,23 @@ static bool __peri_clk_init(struct kona_clk *bcm_clk)
 
 static bool __kona_clk_init(struct kona_clk *bcm_clk)
 {
+	bool ret;
+
+	if (clk_is_initialized(bcm_clk))
+		return true;
+
 	switch (bcm_clk->type) {
 	case bcm_clk_peri:
-		return __peri_clk_init(bcm_clk);
+		ret = __peri_clk_init(bcm_clk);
+		break;
 	default:
+		ret = false;
 		BUG();
 	}
-	return -EINVAL;
+	if (ret)
+		clk_set_initialized(bcm_clk);
+
+	return ret;
 }
 
 /* Set a CCU and all its clocks into their desired initial state */
diff --git a/drivers/clk/bcm/clk-kona.h b/drivers/clk/bcm/clk-kona.h
index 2537b30..10e238d 100644
--- a/drivers/clk/bcm/clk-kona.h
+++ b/drivers/clk/bcm/clk-kona.h
@@ -406,6 +406,7 @@ struct kona_clk {
 	struct clk_init_data init_data;	/* includes name of this clock */
 	struct ccu_data *ccu;	/* ccu this clock is associated with */
 	enum bcm_clk_type type;
+	u32 flags;		/* BCM_CLK_KONA_FLAGS_* below */
 	union {
 		void *data;
 		struct peri_clk_data *peri;
@@ -414,6 +415,12 @@ struct kona_clk {
 #define to_kona_clk(_hw) \
 	container_of(_hw, struct kona_clk, hw)
 
+/*
+ * Kona clock flags:
+ *   INITIALIZED	clock has been initialized already
+ */
+#define BCM_CLK_KONA_FLAGS_INITIALIZED	((u32)1 << 0)	/* Clock initialized */
+
 /* Initialization macro for an entry in a CCU's kona_clks[] array. */
 #define KONA_CLK(_ccu_name, _clk_name, _type)				\
 	{								\
-- 
1.9.1

[PATCH 2/5] clk: bcm281xx: implement prerequisite clocks

[Alex Elder]

Allow a clock to specify a "prerequisite" clock.  The prerequisite
clock must be initialized before the clock that depends on it.  A
prerequisite clock is defined initially by its name; as that clock
gets initialized the name gets replaced with a pointer to its clock
structure pointer.  In order to allow getting a reference to a clock
by its name we call clkdev_add() for each clock as it gets set up.
A new clk_lookup structure is added to the kona_clk type for this
purpose.

Rework the KONA_CLK() macro, and define a new KONA_CLK_PREREQ()
variant that allows a prerequisite clock to be specified.

There exist clocks that could specify more than one prequisite, but
almost all clocks only ever use one.  We can add support for more
than one if we find we need it at some point.

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/clk/bcm/clk-kona-setup.c | 16 ++++++++++----
 drivers/clk/bcm/clk-kona.c       | 45 ++++++++++++++++++++++++++++++++++++++++
 drivers/clk/bcm/clk-kona.h       | 20 +++++++++++++++---
 3 files changed, 74 insertions(+), 7 deletions(-)

diff --git a/drivers/clk/bcm/clk-kona-setup.c b/drivers/clk/bcm/clk-kona-setup.c
index e5aeded..fcce22c 100644
--- a/drivers/clk/bcm/clk-kona-setup.c
+++ b/drivers/clk/bcm/clk-kona-setup.c
@@ -686,6 +686,9 @@ peri_clk_setup(struct peri_clk_data *data, struct clk_init_data *init_data)
 
 static void bcm_clk_teardown(struct kona_clk *bcm_clk)
 {
+	/* There is no function defined for this (yet) */
+	/* clkdev_remove(&bcm_clk->cl); */
+
 	switch (bcm_clk->type) {
 	case bcm_clk_peri:
 		peri_clk_teardown(bcm_clk->u.data, &bcm_clk->init_data);
@@ -719,6 +722,7 @@ static void kona_clk_teardown(struct clk *clk)
 struct clk *kona_clk_setup(struct kona_clk *bcm_clk)
 {
 	struct clk_init_data *init_data = &bcm_clk->init_data;
+	const char *name = init_data->name;
 	struct clk *clk = NULL;
 
 	switch (bcm_clk->type) {
@@ -728,14 +732,13 @@ struct clk *kona_clk_setup(struct kona_clk *bcm_clk)
 		break;
 	default:
 		pr_err("%s: clock type %d invalid for %s\n", __func__,
-			(int)bcm_clk->type, init_data->name);
+			(int)bcm_clk->type, name);
 		return NULL;
 	}
 
 	/* Make sure everything makes sense before we set it up */
 	if (!kona_clk_valid(bcm_clk)) {
-		pr_err("%s: clock data invalid for %s\n", __func__,
-			init_data->name);
+		pr_err("%s: clock data invalid for %s\n", __func__, name);
 		goto out_teardown;
 	}
 
@@ -743,11 +746,16 @@ struct clk *kona_clk_setup(struct kona_clk *bcm_clk)
 	clk = clk_register(NULL, &bcm_clk->hw);
 	if (IS_ERR(clk)) {
 		pr_err("%s: error registering clock %s (%ld)\n", __func__,
-			init_data->name, PTR_ERR(clk));
+			name, PTR_ERR(clk));
 		goto out_teardown;
 	}
 	BUG_ON(!clk);
 
+	/*  Make it so we can look the clock up using clk_find() */
+	bcm_clk->cl.con_id = name;
+	bcm_clk->cl.clk = clk;
+	clkdev_add(&bcm_clk->cl);
+
 	return clk;
 out_teardown:
 	bcm_clk_teardown(bcm_clk);
diff --git a/drivers/clk/bcm/clk-kona.c b/drivers/clk/bcm/clk-kona.c
index d8a7f38..de8047d 100644
--- a/drivers/clk/bcm/clk-kona.c
+++ b/drivers/clk/bcm/clk-kona.c
@@ -1195,6 +1195,48 @@ static bool __peri_clk_init(struct kona_clk *bcm_clk)
 	return true;
 }
 
+static bool __kona_clk_init(struct kona_clk *bcm_clk);
+static bool __kona_prereq_init(struct kona_clk *bcm_clk)
+{
+	struct clk *clk;
+	struct clk_hw *hw;
+	struct kona_clk *prereq;
+
+	BUG_ON(clk_is_initialized(bcm_clk));
+
+	if (!bcm_clk->prereq)
+		return true;
+
+	clk = clk_get(NULL, bcm_clk->prereq);
+	if (IS_ERR(clk)) {
+		pr_err("%s: unable to get prereq clock %s for %s\n",
+			__func__, bcm_clk->prereq, bcm_clk->init_data.name);
+		return false;
+	}
+	hw = __clk_get_hw(clk);
+	if (!hw) {
+		pr_err("%s: null hw pointer for clock %s\n", __func__,
+			bcm_clk->init_data.name);
+		return false;
+	}
+	prereq = to_kona_clk(hw);
+	if (prereq->ccu != bcm_clk->ccu) {
+		pr_err("%s: prereq clock %s CCU different for clock %s\n",
+			__func__, bcm_clk->prereq, bcm_clk->init_data.name);
+		return false;
+	}
+
+	/* Initialize the prerequisite clock first */
+	if (!__kona_clk_init(prereq)) {
+		pr_err("%s: failed to init prereq %s for clock %s\n",
+			__func__, bcm_clk->prereq, bcm_clk->init_data.name);
+		return false;
+	}
+	bcm_clk->prereq_clk = clk;
+
+	return true;
+}
+
 static bool __kona_clk_init(struct kona_clk *bcm_clk)
 {
 	bool ret;
@@ -1202,6 +1244,9 @@ static bool __kona_clk_init(struct kona_clk *bcm_clk)
 	if (clk_is_initialized(bcm_clk))
 		return true;
 
+	if (!__kona_prereq_init(bcm_clk))
+		return false;
+
 	switch (bcm_clk->type) {
 	case bcm_clk_peri:
 		ret = __peri_clk_init(bcm_clk);
diff --git a/drivers/clk/bcm/clk-kona.h b/drivers/clk/bcm/clk-kona.h
index 10e238d..beac016 100644
--- a/drivers/clk/bcm/clk-kona.h
+++ b/drivers/clk/bcm/clk-kona.h
@@ -22,6 +22,8 @@
 #include <linux/device.h>
 #include <linux/of.h>
 #include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/debugfs.h>
 
 #define	BILLION		1000000000
 
@@ -407,6 +409,11 @@ struct kona_clk {
 	struct ccu_data *ccu;	/* ccu this clock is associated with */
 	enum bcm_clk_type type;
 	u32 flags;		/* BCM_CLK_KONA_FLAGS_* below */
+	struct clk_lookup cl;
+	union {
+		const char *prereq;
+		struct clk *prereq_clk;
+	};
 	union {
 		void *data;
 		struct peri_clk_data *peri;
@@ -422,15 +429,22 @@ struct kona_clk {
 #define BCM_CLK_KONA_FLAGS_INITIALIZED	((u32)1 << 0)	/* Clock initialized */
 
 /* Initialization macro for an entry in a CCU's kona_clks[] array. */
-#define KONA_CLK(_ccu_name, _clk_name, _type)				\
-	{								\
+#define ___KONA_CLK_COMMON(_ccu_name, _clk_name, _type)			\
 		.init_data	= {					\
 			.name = #_clk_name,				\
 			.ops = &kona_ ## _type ## _clk_ops,		\
 		},							\
 		.ccu		= &_ccu_name ## _ccu_data,		\
 		.type		= bcm_clk_ ## _type,			\
-		.u.data		= &_clk_name ## _data,			\
+		.u.data		= &_clk_name ## _data
+#define KONA_CLK_PREREQ(_ccu_name, _clk_name, _type, _prereq)		\
+	{								\
+		.prereq		= #_prereq,				\
+		___KONA_CLK_COMMON(_ccu_name, _clk_name, _type),	\
+	}
+#define KONA_CLK(_ccu_name, _clk_name, _type)				\
+	{								\
+		___KONA_CLK_COMMON(_ccu_name, _clk_name, _type),	\
 	}
 #define LAST_KONA_CLK	{ .type = bcm_clk_none }
 
-- 
1.9.1

[PATCH 3/5] clk: bcm281xx: add bus clock support

[Alex Elder]

Add bus clock support.  A bus clock has a subset of the components
present in a peripheral clock (again, all optional): a gate; CCU
policy management bits; and if needed, bits to control hysteresis.

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/clk/bcm/clk-kona-setup.c | 96 ++++++++++++++++++++++++++++++++++++++--
 drivers/clk/bcm/clk-kona.c       | 58 ++++++++++++++++++++++++
 drivers/clk/bcm/clk-kona.h       |  8 ++++
 3 files changed, 159 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/bcm/clk-kona-setup.c b/drivers/clk/bcm/clk-kona-setup.c
index fcce22c..60d18f0 100644
--- a/drivers/clk/bcm/clk-kona-setup.c
+++ b/drivers/clk/bcm/clk-kona-setup.c
@@ -76,6 +76,56 @@ static bool clk_requires_trigger(struct kona_clk *bcm_clk)
 	return divider_exists(div) && !divider_is_fixed(div);
 }
 
+static bool bus_clk_data_offsets_valid(struct kona_clk *bcm_clk)
+{
+	struct bus_clk_data *bus;
+	struct bcm_clk_policy *policy;
+	struct bcm_clk_gate *gate;
+	struct bcm_clk_hyst *hyst;
+	const char *name;
+	u32 limit;
+
+	BUG_ON(bcm_clk->type != bcm_clk_bus);
+	bus = bcm_clk->u.bus;
+	name = bcm_clk->init_data.name;
+
+	limit = bcm_clk->ccu->range - sizeof(u32);
+	limit = round_down(limit, sizeof(u32));
+
+	policy = &bus->policy;
+	if (policy_exists(policy)) {
+		if (policy->offset > limit) {
+			pr_err("%s: bad policy offset for %s (%u > %u)\n",
+				__func__, name, policy->offset, limit);
+			return false;
+		}
+	}
+
+	gate = &bus->gate;
+	hyst = &bus->hyst;
+	if (gate_exists(gate)) {
+		if (gate->offset > limit) {
+			pr_err("%s: bad gate offset for %s (%u > %u)\n",
+				__func__, name, gate->offset, limit);
+			return false;
+		}
+		if (hyst_exists(hyst)) {
+			if (hyst->offset > limit) {
+				pr_err("%s: bad hysteresis offset for %s "
+					"(%u > %u)\n", __func__,
+					name, hyst->offset, limit);
+				return false;
+			}
+		}
+	} else if (hyst_exists(hyst)) {
+		pr_err("%s: hysteresis but no gate for %s\n", __func__, name);
+		return false;
+	}
+
+
+	return true;
+}
+
 static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk)
 {
 	struct peri_clk_data *peri;
@@ -86,15 +136,13 @@ static bool peri_clk_data_offsets_valid(struct kona_clk *bcm_clk)
 	struct bcm_clk_sel *sel;
 	struct bcm_clk_trig *trig;
 	const char *name;
-	u32 range;
 	u32 limit;
 
 	BUG_ON(bcm_clk->type != bcm_clk_peri);
 	peri = bcm_clk->u.peri;
 	name = bcm_clk->init_data.name;
-	range = bcm_clk->ccu->range;
 
-	limit = range - sizeof(u32);
+	limit = bcm_clk->ccu->range - sizeof(u32);
 	limit = round_down(limit, sizeof(u32));
 
 	policy = &peri->policy;
@@ -397,6 +445,23 @@ static bool trig_valid(struct bcm_clk_trig *trig, const char *field_name,
 	return bit_posn_valid(trig->bit, field_name, clock_name);
 }
 
+/* Determine whether the set of bus clock registers are valid. */
+static bool
+bus_clk_data_valid(struct kona_clk *bcm_clk)
+{
+	struct bcm_clk_gate *gate;
+
+	BUG_ON(bcm_clk->type != bcm_clk_bus);
+	if (!bus_clk_data_offsets_valid(bcm_clk))
+		return false;
+
+	gate = &bcm_clk->u.bus->gate;
+	if (!gate_exists(gate))
+		return true;
+
+	return gate_valid(gate, "gate", bcm_clk->init_data.name);
+}
+
 /* Determine whether the set of peripheral clock registers are valid. */
 static bool
 peri_clk_data_valid(struct kona_clk *bcm_clk)
@@ -494,6 +559,10 @@ peri_clk_data_valid(struct kona_clk *bcm_clk)
 static bool kona_clk_valid(struct kona_clk *bcm_clk)
 {
 	switch (bcm_clk->type) {
+	case bcm_clk_bus:
+		if (!bus_clk_data_valid(bcm_clk))
+			return false;
+		break;
 	case bcm_clk_peri:
 		if (!peri_clk_data_valid(bcm_clk))
 			return false;
@@ -664,6 +733,20 @@ static void clk_sel_teardown(struct bcm_clk_sel *sel,
 	init_data->parent_names = NULL;
 }
 
+static void bus_clk_teardown(struct bus_clk_data *data,
+				struct clk_init_data *init_data)
+{
+	/* Nothing to do */
+}
+
+static int
+bus_clk_setup(struct bus_clk_data *data, struct clk_init_data *init_data)
+{
+	init_data->flags = CLK_IGNORE_UNUSED;
+
+	return 0;
+}
+
 static void peri_clk_teardown(struct peri_clk_data *data,
 				struct clk_init_data *init_data)
 {
@@ -690,6 +773,9 @@ static void bcm_clk_teardown(struct kona_clk *bcm_clk)
 	/* clkdev_remove(&bcm_clk->cl); */
 
 	switch (bcm_clk->type) {
+	case bcm_clk_bus:
+		bus_clk_teardown(bcm_clk->u.data, &bcm_clk->init_data);
+		break;
 	case bcm_clk_peri:
 		peri_clk_teardown(bcm_clk->u.data, &bcm_clk->init_data);
 		break;
@@ -726,6 +812,10 @@ struct clk *kona_clk_setup(struct kona_clk *bcm_clk)
 	struct clk *clk = NULL;
 
 	switch (bcm_clk->type) {
+	case bcm_clk_bus:
+		if (bus_clk_setup(bcm_clk->u.data, init_data))
+			return NULL;
+		break;
 	case bcm_clk_peri:
 		if (peri_clk_setup(bcm_clk->u.data, init_data))
 			return NULL;
diff --git a/drivers/clk/bcm/clk-kona.c b/drivers/clk/bcm/clk-kona.c
index de8047d..242dc8d 100644
--- a/drivers/clk/bcm/clk-kona.c
+++ b/drivers/clk/bcm/clk-kona.c
@@ -986,6 +986,36 @@ static int selector_write(struct ccu_data *ccu, struct bcm_clk_gate *gate,
 
 /* Clock operations */
 
+static int kona_bus_clk_enable(struct clk_hw *hw)
+{
+	struct kona_clk *bcm_clk = to_kona_clk(hw);
+	struct bcm_clk_gate *gate = &bcm_clk->u.bus->gate;
+
+	return clk_gate(bcm_clk->ccu, bcm_clk->init_data.name, gate, true);
+}
+
+static void kona_bus_clk_disable(struct clk_hw *hw)
+{
+	struct kona_clk *bcm_clk = to_kona_clk(hw);
+	struct bcm_clk_gate *gate = &bcm_clk->u.bus->gate;
+
+	(void)clk_gate(bcm_clk->ccu, bcm_clk->init_data.name, gate, false);
+}
+
+static int kona_bus_clk_is_enabled(struct clk_hw *hw)
+{
+	struct kona_clk *bcm_clk = to_kona_clk(hw);
+	struct bcm_clk_gate *gate = &bcm_clk->u.bus->gate;
+
+	return is_clk_gate_enabled(bcm_clk->ccu, gate) ? 1 : 0;
+}
+
+struct clk_ops kona_bus_clk_ops = {
+	.enable = kona_bus_clk_enable,
+	.disable = kona_bus_clk_disable,
+	.is_enabled = kona_bus_clk_is_enabled,
+};
+
 static int kona_peri_clk_enable(struct clk_hw *hw)
 {
 	struct kona_clk *bcm_clk = to_kona_clk(hw);
@@ -1144,6 +1174,31 @@ struct clk_ops kona_peri_clk_ops = {
 	.set_rate = kona_peri_clk_set_rate,
 };
 
+/* Put a bus clock into its initial state */
+static bool __bus_clk_init(struct kona_clk *bcm_clk)
+{
+	struct ccu_data *ccu = bcm_clk->ccu;
+	struct bus_clk_data *bus = bcm_clk->u.bus;
+	const char *name = bcm_clk->init_data.name;
+
+	BUG_ON(bcm_clk->type != bcm_clk_bus);
+
+	if (!policy_init(ccu, &bus->policy)) {
+		pr_err("%s: error initializing policy for %s\n",
+			__func__, name);
+		return false;
+	}
+	if (!gate_init(ccu, &bus->gate)) {
+		pr_err("%s: error initializing gate for %s\n", __func__, name);
+		return false;
+	}
+	if (!hyst_init(ccu, &bus->hyst)) {
+		pr_err("%s: error initializing hyst for %s\n", __func__, name);
+		return false;
+	}
+	return true;
+}
+
 /* Put a peripheral clock into its initial state */
 static bool __peri_clk_init(struct kona_clk *bcm_clk)
 {
@@ -1248,6 +1303,9 @@ static bool __kona_clk_init(struct kona_clk *bcm_clk)
 		return false;
 
 	switch (bcm_clk->type) {
+	case bcm_clk_bus:
+		ret = __bus_clk_init(bcm_clk);
+		break;
 	case bcm_clk_peri:
 		ret = __peri_clk_init(bcm_clk);
 		break;
diff --git a/drivers/clk/bcm/clk-kona.h b/drivers/clk/bcm/clk-kona.h
index beac016..436f4ed 100644
--- a/drivers/clk/bcm/clk-kona.h
+++ b/drivers/clk/bcm/clk-kona.h
@@ -389,6 +389,12 @@ struct bcm_clk_trig {
 		.flags = FLAG(TRIG, EXISTS),				\
 	}
 
+struct bus_clk_data {
+	struct bcm_clk_policy policy;
+	struct bcm_clk_gate gate;
+	struct bcm_clk_hyst hyst;
+};
+
 struct peri_clk_data {
 	struct bcm_clk_policy policy;
 	struct bcm_clk_gate gate;
@@ -416,6 +422,7 @@ struct kona_clk {
 	};
 	union {
 		void *data;
+		struct bus_clk_data *bus;
 		struct peri_clk_data *peri;
 	} u;
 };
@@ -520,6 +527,7 @@ struct ccu_data {
 
 /* Exported globals */
 
+extern struct clk_ops kona_bus_clk_ops;
 extern struct clk_ops kona_peri_clk_ops;
 
 /* Externally visible functions */
-- 
1.9.1

[PATCH 4/5] clk: bcm281xx: define a bus clock

[Alex Elder]

Define the bus clock "bsc3_apb".  This bus clock has to be managed
using the CCU policy mechanism, so add the definitions required for
that to the clock and its CCU.

This one bus clock in particular is defined because it is needed
by peripheral clock "bsc3".  Our boot loader does not properly
activate "bsc3_apb", and as a result, "bsc3" isn't able to function
properly.  With "bsc3_apb" specified as a prerequisite clock for
"bsc3", the latter works correctly.

For now only this one bus clock is defined, because it allows
correct operation of "bsc3".  Others can be added later as needed
(and this patch serves to show how that's done).

Signed-off-by: Alex Elder <elder@linaro.org>
---
 drivers/clk/bcm/clk-bcm281xx.c       | 13 ++++++++++++-
 include/dt-bindings/clock/bcm281xx.h |  3 ++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/bcm/clk-bcm281xx.c b/drivers/clk/bcm/clk-bcm281xx.c
index 502a487..b937fc9 100644
--- a/drivers/clk/bcm/clk-bcm281xx.c
+++ b/drivers/clk/bcm/clk-bcm281xx.c
@@ -309,8 +309,17 @@ static struct peri_clk_data pwm_data = {
 	.trig		= TRIGGER(0x0afc, 15),
 };
 
+static struct bus_clk_data bsc3_apb_data = {
+	.policy		= POLICY(0x0048, 4),
+	.gate		= HW_SW_GATE(0x0484, 16, 0, 1),
+};
+
 static struct ccu_data slave_ccu_data = {
 	BCM281XX_CCU_COMMON(slave, SLAVE),
+	.policy		= {
+		.enable		= CCU_LVM_EN(0x0034, 0),
+		.control	= CCU_POLICY_CTL(0x000c, 0, 1, 2),
+	},
 	.kona_clks	= {
 		[BCM281XX_SLAVE_CCU_UARTB] =
 			KONA_CLK(slave, uartb, peri),
@@ -329,9 +338,11 @@ static struct ccu_data slave_ccu_data = {
 		[BCM281XX_SLAVE_CCU_BSC2] =
 			KONA_CLK(slave, bsc2, peri),
 		[BCM281XX_SLAVE_CCU_BSC3] =
-			KONA_CLK(slave, bsc3, peri),
+			KONA_CLK_PREREQ(slave, bsc3, peri, bsc3_apb),
 		[BCM281XX_SLAVE_CCU_PWM] =
 			KONA_CLK(slave, pwm, peri),
+		[BCM281XX_SLAVE_CCU_BSC3_APB] =
+			KONA_CLK(slave, bsc3_apb, bus),
 		[BCM281XX_SLAVE_CCU_CLOCK_COUNT] = LAST_KONA_CLK,
 	},
 };
diff --git a/include/dt-bindings/clock/bcm281xx.h b/include/dt-bindings/clock/bcm281xx.h
index a763460..99f4aad 100644
--- a/include/dt-bindings/clock/bcm281xx.h
+++ b/include/dt-bindings/clock/bcm281xx.h
@@ -72,6 +72,7 @@
 #define BCM281XX_SLAVE_CCU_BSC2			7
 #define BCM281XX_SLAVE_CCU_BSC3			8
 #define BCM281XX_SLAVE_CCU_PWM			9
-#define BCM281XX_SLAVE_CCU_CLOCK_COUNT		10
+#define BCM281XX_SLAVE_CCU_BSC3_APB		10
+#define BCM281XX_SLAVE_CCU_CLOCK_COUNT		11
 
 #endif /* _CLOCK_BCM281XX_H */
-- 
1.9.1

[PATCH 5/5] ARM: dts: add bus clock bsc3_apb for bcm281xx

[Alex Elder]

Add the bus clock named "bsc3_apb" to the list of those provided by
the slave CCU.

Signed-off-by: Alex Elder <elder@linaro.org>
---
 arch/arm/boot/dts/bcm11351.dtsi | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/bcm11351.dtsi b/arch/arm/boot/dts/bcm11351.dtsi
index 64d069b..faff8af 100644
--- a/arch/arm/boot/dts/bcm11351.dtsi
+++ b/arch/arm/boot/dts/bcm11351.dtsi
@@ -247,7 +247,8 @@
 					     "bsc1",
 					     "bsc2",
 					     "bsc3",
-					     "pwm";
+					     "pwm",
+					     "bsc3_apb";
 		};
 
 		ref_1m_clk: ref_1m {
-- 
1.9.1