Re: [PATCH v2 1/5] clk: bcm281xx: add an initialized flag
On 05/23/2014 07:33 PM, Mike Turquette wrote:
> Quoting Alex Elder (2014-05-20 05:52:38)
>> 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
>> ---
>> 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);
>
> Hi Alex,
>
> Going through this code, it's a bit hard to keep up ;-)
Here's how the structures are organized:
- A Kona clock is either a peripheral or a bus clock,
but a lot of things are handled generically at the
Kona level of abstraction.
- A peripheral clock has a selector (mux), up to two
dividers, and a gate. All of these are optional.
- A bus clock has a gate, which is optional. (There
are a few other things but I'm just ignoring them
for now.)
- Each of these sort of sub-components (gate, divider,
etc.) are handled on their own. In other words, there
are gate routines that operate on a gate regardless
of whether it's on bus or peripheral clock.
- These sub-components are grouped like this because
there are some weird gating requirements. (I've
said before I wanted to try to split things off where
possible to use the common framework code more, but
that opportunity hasn't arisen yet.)
> Does the call to __peri_clk_init enable the prereq clocks? If so, is
> their clk->prepare_count and clk->enable_count properly incremented?
My use of the term "enable" is imprecise.
The purpose of these *_init() routines is to set the hardware
to a known initial state. Right now, *defining* what that
state should be has not been sent out for review, but that's
the reason it's set up this way. The model is basically, when
you want to make a change, you record what the new value should
be and the *_commit() it. Special values, used at initialization
time, indicate we don't have a desired value but we don't know
what the hardware is currently is set to either. When those
special values (like BAD_SCALED_DIV_VALUE) are seen, the current
value is read from the hardware rather than written.
Anyway, to (hopefully) answer your question...
All of the prerequisite activity occurs in __kona_clk_init(),
which is called for every Kona clock. The first thing that
does is call __kona_prereq_init(), in order to set up and
initialize (using __kona_clk_init()) the prerequisite clock
if there is one.
*After* the prerequisite clock is set up, the rest of the
original clock initialization occurs, by calling (e.g.)
__peri_clk_init().
Sorry to be so verbose but I think it helps to understand
the design underlying this stuff.
I'm going to be submitting a new version of this series
today. It will pull out the clk_lookup field and
some comments that you spotted that are just dead code.
-Alex
> Thanks,
> Mike
>
>> + 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)
>>
Re: [PATCH v2 1/5] clk: bcm281xx: add an initialized flag
On 05/23/2014 07:33 PM, Mike Turquette wrote:
Quoting Alex Elder (2014-05-20 05:52:38)
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 el...@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);
Hi Alex,
Going through this code, it's a bit hard to keep up ;-)
Here's how the structures are organized:
- A Kona clock is either a peripheral or a bus clock,
but a lot of things are handled generically at the
Kona level of abstraction.
- A peripheral clock has a selector (mux), up to two
dividers, and a gate. All of these are optional.
- A bus clock has a gate, which is optional. (There
are a few other things but I'm just ignoring them
for now.)
- Each of these sort of sub-components (gate, divider,
etc.) are handled on their own. In other words, there
are gate routines that operate on a gate regardless
of whether it's on bus or peripheral clock.
- These sub-components are grouped like this because
there are some weird gating requirements. (I've
said before I wanted to try to split things off where
possible to use the common framework code more, but
that opportunity hasn't arisen yet.)
Does the call to __peri_clk_init enable the prereq clocks? If so, is
their clk-prepare_count and clk-enable_count properly incremented?
My use of the term enable is imprecise.
The purpose of these *_init() routines is to set the hardware
to a known initial state. Right now, *defining* what that
state should be has not been sent out for review, but that's
the reason it's set up this way. The model is basically, when
you want to make a change, you record what the new value should
be and the *_commit() it. Special values, used at initialization
time, indicate we don't have a desired value but we don't know
what the hardware is currently is set to either. When those
special values (like BAD_SCALED_DIV_VALUE) are seen, the current
value is read from the hardware rather than written.
Anyway, to (hopefully) answer your question...
All of the prerequisite activity occurs in __kona_clk_init(),
which is called for every Kona clock. The first thing that
does is call __kona_prereq_init(), in order to set up and
initialize (using __kona_clk_init()) the prerequisite clock
if there is one.
*After* the prerequisite clock is set up, the rest of the
original clock initialization occurs, by calling (e.g.)
__peri_clk_init().
Sorry to be so verbose but I think it helps to understand
the design underlying this stuff.
I'm going to be submitting a new version of this series
today. It will pull out the clk_lookup field and
some comments that you spotted that are just dead code.
-Alex
Thanks,
Mike
+ 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
Re: [PATCH v2 1/5] clk: bcm281xx: add an initialized flag
Quoting Alex Elder (2014-05-20 05:52:38)
> 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
> ---
> 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);
Hi Alex,
Going through this code, it's a bit hard to keep up ;-)
Does the call to __peri_clk_init enable the prereq clocks? If so, is
their clk->prepare_count and clk->enable_count properly incremented?
Thanks,
Mike
> + 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
>
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Re: [PATCH v2 1/5] clk: bcm281xx: add an initialized flag
Quoting Alex Elder (2014-05-20 05:52:38)
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 el...@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);
Hi Alex,
Going through this code, it's a bit hard to keep up ;-)
Does the call to __peri_clk_init enable the prereq clocks? If so, is
their clk-prepare_count and clk-enable_count properly incremented?
Thanks,
Mike
+ 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
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[PATCH v2 1/5] clk: bcm281xx: add an initialized flag
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
---
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
--
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Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 1/5] clk: bcm281xx: add an initialized flag
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 el...@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
--
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