2023-10-03 11:44:27

by Peng Fan (OSS)

[permalink] [raw]
Subject: [PATCH v4 0/2] firmware: arm_scmi: clock: support parents commands

SCMI v3.2 spec adds parents commands, this patchset is to support them:
CLOCK_POSSIBLE_PARENTS_GET
CLOCK_PARENT_SET
CLOCK_PARENT_GET

Besides firmware api clock driver update, the clk_scmi driver also
updated to support set_parent and get_parent ops.

Signed-off-by: Peng Fan <[email protected]>

To: Sudeep Holla <[email protected]>
To: Cristian Marussi <[email protected]>
To: Michael Turquette <[email protected]>
To: Stephen Boyd <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

Changes in v4:
Included Cristian's fix in patch 2 for get parent. Thanks, Cristian.
Add Cristian's R-b in patch 1
Rebased on https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git/log/?h=for-next/scmi/updates
- Link to v3: https://lore.kernel.org/all/[email protected]/

Changes in v3:
Address Cristian's comments:
- Drop SCMI_MAX_NUM_PARENTS, alloc memory dynamically
- Check clk_id, parent_id
- Add comment for parent_get/set
- Link to v2: https://lore.kernel.org/r/[email protected]

Changes in V2:
- Add determine_rate hooks

---
Peng Fan (2):
firmware: arm_scmi: clock: support clock parents
clk: scmi: add set/get_parent support

drivers/clk/clk-scmi.c | 58 +++++++++++-
drivers/firmware/arm_scmi/clock.c | 182 ++++++++++++++++++++++++++++++++++++--
include/linux/scmi_protocol.h | 6 ++
3 files changed, 239 insertions(+), 7 deletions(-)
---
base-commit: 8b6022be4c6e3e0d37c3e1378c9ff0a2c8717b09
change-id: 20231003-scmi-clock-v3-ae65eb755d15

Best regards,
--
Peng Fan <[email protected]>


2023-10-03 11:44:36

by Peng Fan (OSS)

[permalink] [raw]
Subject: [PATCH v4 1/2] firmware: arm_scmi: clock: support clock parents

From: Peng Fan <[email protected]>

SCMI v3.2 spec introduces CLOCK_POSSIBLE_PARENTS_GET, CLOCK_PARENT_SET
and CLOCK_PARENT_GET. This patch is to add the upper three new
commands.

Reviewed-by: Cristian Marussi <[email protected]>
Signed-off-by: Peng Fan <[email protected]>
---
drivers/firmware/arm_scmi/clock.c | 182 ++++++++++++++++++++++++++++++++++++--
include/linux/scmi_protocol.h | 6 ++
2 files changed, 182 insertions(+), 6 deletions(-)

diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index 9c0e33c1efab..ddaef34cd88b 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -22,6 +22,9 @@ enum scmi_clock_protocol_cmd {
CLOCK_RATE_NOTIFY = 0x9,
CLOCK_RATE_CHANGE_REQUESTED_NOTIFY = 0xA,
CLOCK_CONFIG_GET = 0xB,
+ CLOCK_POSSIBLE_PARENTS_GET = 0xC,
+ CLOCK_PARENT_SET = 0xD,
+ CLOCK_PARENT_GET = 0xE,
};

enum clk_state {
@@ -42,10 +45,28 @@ struct scmi_msg_resp_clock_attributes {
#define SUPPORTS_RATE_CHANGED_NOTIF(x) ((x) & BIT(31))
#define SUPPORTS_RATE_CHANGE_REQUESTED_NOTIF(x) ((x) & BIT(30))
#define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(29))
+#define SUPPORTS_PARENT_CLOCK(x) ((x) & BIT(28))
u8 name[SCMI_SHORT_NAME_MAX_SIZE];
__le32 clock_enable_latency;
};

+struct scmi_msg_clock_possible_parents {
+ __le32 id;
+ __le32 skip_parents;
+};
+
+struct scmi_msg_resp_clock_possible_parents {
+ __le32 num_parent_flags;
+#define NUM_PARENTS_RETURNED(x) ((x) & 0xff)
+#define NUM_PARENTS_REMAINING(x) ((x) >> 24)
+ u32 possible_parents[];
+};
+
+struct scmi_msg_clock_set_parent {
+ __le32 id;
+ __le32 parent_id;
+};
+
struct scmi_msg_clock_config_set {
__le32 id;
__le32 attributes;
@@ -168,6 +189,99 @@ scmi_clock_protocol_attributes_get(const struct scmi_protocol_handle *ph,
return ret;
}

+struct scmi_clk_ipriv {
+ struct device *dev;
+ u32 clk_id;
+ struct scmi_clock_info *clk;
+};
+
+static void iter_clk_possible_parents_prepare_message(void *message, unsigned int desc_index,
+ const void *priv)
+{
+ struct scmi_msg_clock_possible_parents *msg = message;
+ const struct scmi_clk_ipriv *p = priv;
+
+ msg->id = cpu_to_le32(p->clk_id);
+ /* Set the number of OPPs to be skipped/already read */
+ msg->skip_parents = cpu_to_le32(desc_index);
+}
+
+static int iter_clk_possible_parents_update_state(struct scmi_iterator_state *st,
+ const void *response, void *priv)
+{
+ const struct scmi_msg_resp_clock_possible_parents *r = response;
+ struct scmi_clk_ipriv *p = priv;
+ struct device *dev = ((struct scmi_clk_ipriv *)p)->dev;
+ u32 flags;
+
+ flags = le32_to_cpu(r->num_parent_flags);
+ st->num_returned = NUM_PARENTS_RETURNED(flags);
+ st->num_remaining = NUM_PARENTS_REMAINING(flags);
+
+ /*
+ * num parents is not declared previously anywhere so we
+ * assume it's returned+remaining on first call.
+ */
+ if (!st->max_resources) {
+ p->clk->num_parents = st->num_returned + st->num_remaining;
+ p->clk->parents = devm_kcalloc(dev, p->clk->num_parents,
+ sizeof(*p->clk->parents),
+ GFP_KERNEL);
+ if (!p->clk->parents) {
+ p->clk->num_parents = 0;
+ return -ENOMEM;
+ }
+
+ st->max_resources = st->num_returned + st->num_remaining;
+ };
+
+ return 0;
+}
+
+static int iter_clk_possible_parents_process_response(const struct scmi_protocol_handle *ph,
+ const void *response,
+ struct scmi_iterator_state *st,
+ void *priv)
+{
+ const struct scmi_msg_resp_clock_possible_parents *r = response;
+ struct scmi_clk_ipriv *p = priv;
+
+ u32 *parent = &p->clk->parents[st->desc_index + st->loop_idx];
+
+ *parent = le32_to_cpu(r->possible_parents[st->loop_idx]);
+
+ return 0;
+}
+
+static int scmi_clock_possible_parents(const struct scmi_protocol_handle *ph, u32 clk_id,
+ struct scmi_clock_info *clk)
+{
+ struct scmi_iterator_ops ops = {
+ .prepare_message = iter_clk_possible_parents_prepare_message,
+ .update_state = iter_clk_possible_parents_update_state,
+ .process_response = iter_clk_possible_parents_process_response,
+ };
+
+ struct scmi_clk_ipriv ppriv = {
+ .clk_id = clk_id,
+ .clk = clk,
+ .dev = ph->dev,
+ };
+ void *iter;
+ int ret;
+
+ iter = ph->hops->iter_response_init(ph, &ops, 0,
+ CLOCK_POSSIBLE_PARENTS_GET,
+ sizeof(struct scmi_msg_clock_possible_parents),
+ &ppriv);
+ if (IS_ERR(iter))
+ return PTR_ERR(iter);
+
+ ret = ph->hops->iter_response_run(iter);
+
+ return ret;
+}
+
static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
u32 clk_id, struct scmi_clock_info *clk,
u32 version)
@@ -212,6 +326,8 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
clk->rate_changed_notifications = true;
if (SUPPORTS_RATE_CHANGE_REQUESTED_NOTIF(attributes))
clk->rate_change_requested_notifications = true;
+ if (SUPPORTS_PARENT_CLOCK(attributes))
+ scmi_clock_possible_parents(ph, clk_id, clk);
}

return ret;
@@ -229,12 +345,6 @@ static int rate_cmp_func(const void *_r1, const void *_r2)
return 1;
}

-struct scmi_clk_ipriv {
- struct device *dev;
- u32 clk_id;
- struct scmi_clock_info *clk;
-};
-
static void iter_clk_describe_prepare_message(void *message,
const unsigned int desc_index,
const void *priv)
@@ -458,6 +568,64 @@ scmi_clock_config_set(const struct scmi_protocol_handle *ph, u32 clk_id,
return ret;
}

+static int
+scmi_clock_set_parent(const struct scmi_protocol_handle *ph, u32 clk_id,
+ u32 parent_id)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct scmi_msg_clock_set_parent *cfg;
+ struct clock_info *ci = ph->get_priv(ph);
+ struct scmi_clock_info *clk;
+
+ if (clk_id >= ci->num_clocks)
+ return -EINVAL;
+
+ clk = ci->clk + clk_id;
+
+ if (parent_id >= clk->num_parents)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_SET,
+ sizeof(*cfg), 0, &t);
+ if (ret)
+ return ret;
+
+ t->hdr.poll_completion = false;
+
+ cfg = t->tx.buf;
+ cfg->id = cpu_to_le32(clk_id);
+ cfg->parent_id = cpu_to_le32(clk->parents[parent_id]);
+
+ ret = ph->xops->do_xfer(ph, t);
+
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int
+scmi_clock_get_parent(const struct scmi_protocol_handle *ph, u32 clk_id,
+ u32 *parent_id)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_GET,
+ sizeof(__le32), sizeof(u32), &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(clk_id, t->tx.buf);
+
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret)
+ *parent_id = get_unaligned_le32(t->rx.buf);
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
/* For SCMI clock v2.1 and onwards */
static int
scmi_clock_config_set_v2(const struct scmi_protocol_handle *ph, u32 clk_id,
@@ -650,6 +818,8 @@ static const struct scmi_clk_proto_ops clk_proto_ops = {
.state_get = scmi_clock_state_get,
.config_oem_get = scmi_clock_config_oem_get,
.config_oem_set = scmi_clock_config_oem_set,
+ .parent_set = scmi_clock_set_parent,
+ .parent_get = scmi_clock_get_parent,
};

static int scmi_clk_rate_notify(const struct scmi_protocol_handle *ph,
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 27bfa5a65b45..f2f05fb42d28 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -58,6 +58,8 @@ struct scmi_clock_info {
u64 step_size;
} range;
};
+ int num_parents;
+ u32 *parents;
};

enum scmi_power_scale {
@@ -83,6 +85,8 @@ struct scmi_protocol_handle;
* @state_get: get the status of the specified clock
* @config_oem_get: get the value of an OEM specific clock config
* @config_oem_set: set the value of an OEM specific clock config
+ * @parent_get: get the parent id of a clk
+ * @parent_set: set the parent of a clock
*/
struct scmi_clk_proto_ops {
int (*count_get)(const struct scmi_protocol_handle *ph);
@@ -104,6 +108,8 @@ struct scmi_clk_proto_ops {
bool atomic);
int (*config_oem_set)(const struct scmi_protocol_handle *ph, u32 clk_id,
u8 oem_type, u32 oem_val, bool atomic);
+ int (*parent_get)(const struct scmi_protocol_handle *ph, u32 clk_id, u32 *parent_id);
+ int (*parent_set)(const struct scmi_protocol_handle *ph, u32 clk_id, u32 parent_id);
};

struct scmi_perf_domain_info {

--
2.37.1

2023-10-03 11:44:41

by Peng Fan (OSS)

[permalink] [raw]
Subject: [PATCH v4 2/2] clk: scmi: add set/get_parent support

From: Peng Fan <[email protected]>

SCMI v3.2 adds set/get parent clock commands, so update the clk driver
to support them.

Signed-off-by: Peng Fan <[email protected]>
---
drivers/clk/clk-scmi.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 57 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 2e1337b511eb..e7a27fda561b 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -24,6 +24,7 @@ struct scmi_clk {
struct clk_hw hw;
const struct scmi_clock_info *info;
const struct scmi_protocol_handle *ph;
+ struct clk_parent_data *parent_data;
};

#define to_scmi_clk(clk) container_of(clk, struct scmi_clk, hw)
@@ -78,6 +79,43 @@ static int scmi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
return scmi_proto_clk_ops->rate_set(clk->ph, clk->id, rate);
}

+static int scmi_clk_set_parent(struct clk_hw *hw, u8 parent_index)
+{
+ struct scmi_clk *clk = to_scmi_clk(hw);
+
+ return scmi_proto_clk_ops->parent_set(clk->ph, clk->id, parent_index);
+}
+
+static u8 scmi_clk_get_parent(struct clk_hw *hw)
+{
+ struct scmi_clk *clk = to_scmi_clk(hw);
+ u32 parent_id, p_idx;
+ int ret;
+
+ ret = scmi_proto_clk_ops->parent_get(clk->ph, clk->id, &parent_id);
+ if (ret)
+ return 0;
+
+ for (p_idx = 0; p_idx < clk->info->num_parents; p_idx++) {
+ if (clk->parent_data[p_idx].index == parent_id)
+ break;
+ }
+
+ if (p_idx == clk->info->num_parents)
+ return 0;
+
+ return p_idx;
+}
+
+static int scmi_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ /*
+ * Suppose all the requested rates are supported, and let firmware
+ * to handle the left work.
+ */
+ return 0;
+}
+
static int scmi_clk_enable(struct clk_hw *hw)
{
struct scmi_clk *clk = to_scmi_clk(hw);
@@ -139,6 +177,9 @@ static const struct clk_ops scmi_clk_ops = {
.set_rate = scmi_clk_set_rate,
.prepare = scmi_clk_enable,
.unprepare = scmi_clk_disable,
+ .set_parent = scmi_clk_set_parent,
+ .get_parent = scmi_clk_get_parent,
+ .determine_rate = scmi_clk_determine_rate,
};

static const struct clk_ops scmi_atomic_clk_ops = {
@@ -148,6 +189,9 @@ static const struct clk_ops scmi_atomic_clk_ops = {
.enable = scmi_clk_atomic_enable,
.disable = scmi_clk_atomic_disable,
.is_enabled = scmi_clk_atomic_is_enabled,
+ .set_parent = scmi_clk_set_parent,
+ .get_parent = scmi_clk_get_parent,
+ .determine_rate = scmi_clk_determine_rate,
};

static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
@@ -158,9 +202,10 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,

struct clk_init_data init = {
.flags = CLK_GET_RATE_NOCACHE,
- .num_parents = 0,
+ .num_parents = sclk->info->num_parents,
.ops = scmi_ops,
.name = sclk->info->name,
+ .parent_data = sclk->parent_data,
};

sclk->hw.init = &init;
@@ -250,6 +295,17 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
else
scmi_ops = &scmi_clk_ops;

+ /* Initialize clock parent data. */
+ if (sclk->info->num_parents > 0) {
+ sclk->parent_data = devm_kcalloc(dev, sclk->info->num_parents,
+ sizeof(*sclk->parent_data), GFP_KERNEL);
+
+ for (int i = 0; i < sclk->info->num_parents; i++) {
+ sclk->parent_data[i].index = sclk->info->parents[i];
+ sclk->parent_data[i].hw = hws[sclk->info->parents[i]];
+ }
+ }
+
err = scmi_clk_ops_init(dev, sclk, scmi_ops);
if (err) {
dev_err(dev, "failed to register clock %d\n", idx);

--
2.37.1

2023-10-03 12:13:54

by Cristian Marussi

[permalink] [raw]
Subject: Re: [PATCH v4 2/2] clk: scmi: add set/get_parent support

On Tue, Oct 03, 2023 at 07:48:49PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
> SCMI v3.2 adds set/get parent clock commands, so update the clk driver
> to support them.
>

Hi,

in general LGTM, BUT I have just spotted one more *bad* thing that have to be
fixe down below which I have missed previously, my bad.

> Signed-off-by: Peng Fan <[email protected]>
> ---
> drivers/clk/clk-scmi.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 57 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
> index 2e1337b511eb..e7a27fda561b 100644
> --- a/drivers/clk/clk-scmi.c
> +++ b/drivers/clk/clk-scmi.c
> @@ -24,6 +24,7 @@ struct scmi_clk {
> struct clk_hw hw;
> const struct scmi_clock_info *info;
> const struct scmi_protocol_handle *ph;
> + struct clk_parent_data *parent_data;
> };
>
> #define to_scmi_clk(clk) container_of(clk, struct scmi_clk, hw)
> @@ -78,6 +79,43 @@ static int scmi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
> return scmi_proto_clk_ops->rate_set(clk->ph, clk->id, rate);
> }
>
> +static int scmi_clk_set_parent(struct clk_hw *hw, u8 parent_index)
> +{
> + struct scmi_clk *clk = to_scmi_clk(hw);
> +
> + return scmi_proto_clk_ops->parent_set(clk->ph, clk->id, parent_index);
> +}
> +
> +static u8 scmi_clk_get_parent(struct clk_hw *hw)
> +{
> + struct scmi_clk *clk = to_scmi_clk(hw);
> + u32 parent_id, p_idx;
> + int ret;
> +
> + ret = scmi_proto_clk_ops->parent_get(clk->ph, clk->id, &parent_id);
> + if (ret)
> + return 0;
> +
> + for (p_idx = 0; p_idx < clk->info->num_parents; p_idx++) {
> + if (clk->parent_data[p_idx].index == parent_id)
> + break;
> + }
> +
> + if (p_idx == clk->info->num_parents)
> + return 0;
> +
> + return p_idx;
> +}
> +
> +static int scmi_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
> +{
> + /*
> + * Suppose all the requested rates are supported, and let firmware
> + * to handle the left work.
> + */
> + return 0;
> +}
> +
> static int scmi_clk_enable(struct clk_hw *hw)
> {
> struct scmi_clk *clk = to_scmi_clk(hw);
> @@ -139,6 +177,9 @@ static const struct clk_ops scmi_clk_ops = {
> .set_rate = scmi_clk_set_rate,
> .prepare = scmi_clk_enable,
> .unprepare = scmi_clk_disable,
> + .set_parent = scmi_clk_set_parent,
> + .get_parent = scmi_clk_get_parent,
> + .determine_rate = scmi_clk_determine_rate,
> };
>
> static const struct clk_ops scmi_atomic_clk_ops = {
> @@ -148,6 +189,9 @@ static const struct clk_ops scmi_atomic_clk_ops = {
> .enable = scmi_clk_atomic_enable,
> .disable = scmi_clk_atomic_disable,
> .is_enabled = scmi_clk_atomic_is_enabled,
> + .set_parent = scmi_clk_set_parent,
> + .get_parent = scmi_clk_get_parent,
> + .determine_rate = scmi_clk_determine_rate,
> };
>
> static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
> @@ -158,9 +202,10 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk,
>
> struct clk_init_data init = {
> .flags = CLK_GET_RATE_NOCACHE,
> - .num_parents = 0,
> + .num_parents = sclk->info->num_parents,
> .ops = scmi_ops,
> .name = sclk->info->name,
> + .parent_data = sclk->parent_data,
> };
>
> sclk->hw.init = &init;
> @@ -250,6 +295,17 @@ static int scmi_clocks_probe(struct scmi_device *sdev)
> else
> scmi_ops = &scmi_clk_ops;
>
> + /* Initialize clock parent data. */
> + if (sclk->info->num_parents > 0) {
> + sclk->parent_data = devm_kcalloc(dev, sclk->info->num_parents,
> + sizeof(*sclk->parent_data), GFP_KERNEL);
> +

Here, you missed to check the return value of devm_kcalloc() before carrying on.

> + for (int i = 0; i < sclk->info->num_parents; i++) {
> + sclk->parent_data[i].index = sclk->info->parents[i];
> + sclk->parent_data[i].hw = hws[sclk->info->parents[i]];
> + }
> + }
> +

Other than this, FWIW:

Reviewed-by: Cristian Marussi <[email protected]>

Thanks,
Cristian