From: Peng Fan <[email protected]>
ARM SCMI Spec 3.2 introduces Clock Get Permission command. This patch
is to add the support. Add three bool entries to scmi_clock_info to
indicate the operation is forbidden or not. If the CLOCK_GET_PERMISSIONS
command is not supported, the three bool variables will default
set to false, otherwise they will be set according to the return result
of CLOCK_GET_PERMISSIONS.
Signed-off-by: Peng Fan <[email protected]>
---
V2:
Take Cristian's suggestion, https://lore.kernel.org/all/ZWiqqfQ73tezFmSk@pluto/
drivers/firmware/arm_scmi/clock.c | 53 +++++++++++++++++++++++++++++++
include/linux/scmi_protocol.h | 4 +++
2 files changed, 57 insertions(+)
diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index 98511a3aa367..0e048530bea2 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -25,8 +25,13 @@ enum scmi_clock_protocol_cmd {
CLOCK_POSSIBLE_PARENTS_GET = 0xC,
CLOCK_PARENT_SET = 0xD,
CLOCK_PARENT_GET = 0xE,
+ CLOCK_GET_PERMISSIONS = 0xF,
};
+#define CLOCK_STATE_CONTROL_ALLOWED BIT(31)
+#define CLOCK_PARENT_CONTROL_ALLOWED BIT(30)
+#define CLOCK_RATE_CONTROL_ALLOWED BIT(29)
+
enum clk_state {
CLK_STATE_DISABLE,
CLK_STATE_ENABLE,
@@ -46,6 +51,7 @@ struct scmi_msg_resp_clock_attributes {
#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))
+#define SUPPORTS_GET_PERMISSIONS(x) ((x) & BIT(1))
u8 name[SCMI_SHORT_NAME_MAX_SIZE];
__le32 clock_enable_latency;
};
@@ -281,6 +287,35 @@ static int scmi_clock_possible_parents(const struct scmi_protocol_handle *ph, u3
return ret;
}
+static int
+scmi_clock_get_permissions(const struct scmi_protocol_handle *ph, u32 clk_id,
+ struct scmi_clock_info *clk)
+{
+ struct scmi_xfer *t;
+ u32 perm;
+ int ret;
+
+ ret = ph->xops->xfer_get_init(ph, CLOCK_GET_PERMISSIONS,
+ sizeof(clk_id), sizeof(perm), &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(clk_id, t->tx.buf);
+
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret) {
+ perm = get_unaligned_le32(t->rx.buf);
+
+ clk->state_ctrl_forbidden = !(perm & CLOCK_STATE_CONTROL_ALLOWED);
+ clk->rate_ctrl_forbidden = !(perm & CLOCK_RATE_CONTROL_ALLOWED);
+ clk->parent_ctrl_forbidden = !(perm & CLOCK_PARENT_CONTROL_ALLOWED);
+ }
+
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
u32 clk_id, struct scmi_clock_info *clk,
u32 version)
@@ -307,6 +342,7 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
if (PROTOCOL_REV_MAJOR(version) >= 0x2)
latency = le32_to_cpu(attr->clock_enable_latency);
clk->enable_latency = latency ? : U32_MAX;
+ clk->attributes = attributes;
}
ph->xops->xfer_put(ph, t);
@@ -327,6 +363,8 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
clk->rate_change_requested_notifications = true;
if (SUPPORTS_PARENT_CLOCK(attributes))
scmi_clock_possible_parents(ph, clk_id, clk);
+ if (SUPPORTS_GET_PERMISSIONS(attributes))
+ scmi_clock_get_permissions(ph, clk_id, clk);
}
return ret;
@@ -499,6 +537,10 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
struct scmi_xfer *t;
struct scmi_clock_set_rate *cfg;
struct clock_info *ci = ph->get_priv(ph);
+ struct scmi_clock_info *clk = ci->clk + clk_id;
+
+ if (clk->rate_ctrl_forbidden)
+ return -EACCES;
ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, &t);
if (ret)
@@ -585,6 +627,9 @@ scmi_clock_set_parent(const struct scmi_protocol_handle *ph, u32 clk_id,
if (parent_id >= clk->num_parents)
return -EINVAL;
+ if (clk->parent_ctrl_forbidden)
+ return -EACCES;
+
ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_SET,
sizeof(*cfg), 0, &t);
if (ret)
@@ -668,6 +713,10 @@ static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id,
bool atomic)
{
struct clock_info *ci = ph->get_priv(ph);
+ struct scmi_clock_info *clk = ci->clk + clk_id;
+
+ if (clk->state_ctrl_forbidden)
+ return -EACCES;
return ci->clock_config_set(ph, clk_id, CLK_STATE_ENABLE,
NULL_OEM_TYPE, 0, atomic);
@@ -677,6 +726,10 @@ static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id,
bool atomic)
{
struct clock_info *ci = ph->get_priv(ph);
+ struct scmi_clock_info *clk = ci->clk + clk_id;
+
+ if (clk->state_ctrl_forbidden)
+ return -EACCES;
return ci->clock_config_set(ph, clk_id, CLK_STATE_DISABLE,
NULL_OEM_TYPE, 0, atomic);
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index f2f05fb42d28..ad75784b567b 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -47,6 +47,9 @@ struct scmi_clock_info {
bool rate_discrete;
bool rate_changed_notifications;
bool rate_change_requested_notifications;
+ bool state_ctrl_forbidden;
+ bool rate_ctrl_forbidden;
+ bool parent_ctrl_forbidden;
union {
struct {
int num_rates;
@@ -60,6 +63,7 @@ struct scmi_clock_info {
};
int num_parents;
u32 *parents;
+ u32 attributes;
};
enum scmi_power_scale {
--
2.37.1
From: Peng Fan <[email protected]>
Some clocks may exported to linux, while those clocks are not allowed
to configure by Linux. For example:
SYS_CLK1-----
\
--MUX--->MMC1_CLK
/
SYS_CLK2-----
MMC1 needs set parent, so SYS_CLK1 and SYS_CLK2 are exported to Linux,
then the clk propagation will touch SYS_CLK1 or SYS_CLK2.
So we need bypass the failure for SYS_CLK1 or SYS_CLK2 when enable
the clock of MMC1.
Signed-off-by: Peng Fan <[email protected]>
---
V2:
New. Take Cristian's suggestion
drivers/clk/clk-scmi.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 8cbe24789c24..1d809813eabd 100644
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -119,8 +119,14 @@ static int scmi_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *r
static int scmi_clk_enable(struct clk_hw *hw)
{
struct scmi_clk *clk = to_scmi_clk(hw);
+ int ret;
+
+ ret = scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC);
- return scmi_proto_clk_ops->enable(clk->ph, clk->id, NOT_ATOMIC);
+ if (ret == -EACCES && clk->info->state_ctrl_forbidden)
+ return 0;
+
+ return ret;
}
static void scmi_clk_disable(struct clk_hw *hw)
--
2.37.1
Hi Sudeep, Cristian,
Are you ok with this patchset? It's been pending for 1 month.
Thanks,
Peng.
On 12/7/2023 5:33 PM, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
> ARM SCMI Spec 3.2 introduces Clock Get Permission command. This patch
> is to add the support. Add three bool entries to scmi_clock_info to
> indicate the operation is forbidden or not. If the CLOCK_GET_PERMISSIONS
> command is not supported, the three bool variables will default
> set to false, otherwise they will be set according to the return result
> of CLOCK_GET_PERMISSIONS.
>
> Signed-off-by: Peng Fan <[email protected]>
> ---
>
> V2:
> Take Cristian's suggestion, https://lore.kernel.org/all/ZWiqqfQ73tezFmSk@pluto/
>
> drivers/firmware/arm_scmi/clock.c | 53 +++++++++++++++++++++++++++++++
> include/linux/scmi_protocol.h | 4 +++
> 2 files changed, 57 insertions(+)
>
> diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
> index 98511a3aa367..0e048530bea2 100644
> --- a/drivers/firmware/arm_scmi/clock.c
> +++ b/drivers/firmware/arm_scmi/clock.c
> @@ -25,8 +25,13 @@ enum scmi_clock_protocol_cmd {
> CLOCK_POSSIBLE_PARENTS_GET = 0xC,
> CLOCK_PARENT_SET = 0xD,
> CLOCK_PARENT_GET = 0xE,
> + CLOCK_GET_PERMISSIONS = 0xF,
> };
>
> +#define CLOCK_STATE_CONTROL_ALLOWED BIT(31)
> +#define CLOCK_PARENT_CONTROL_ALLOWED BIT(30)
> +#define CLOCK_RATE_CONTROL_ALLOWED BIT(29)
> +
> enum clk_state {
> CLK_STATE_DISABLE,
> CLK_STATE_ENABLE,
> @@ -46,6 +51,7 @@ struct scmi_msg_resp_clock_attributes {
> #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))
> +#define SUPPORTS_GET_PERMISSIONS(x) ((x) & BIT(1))
> u8 name[SCMI_SHORT_NAME_MAX_SIZE];
> __le32 clock_enable_latency;
> };
> @@ -281,6 +287,35 @@ static int scmi_clock_possible_parents(const struct scmi_protocol_handle *ph, u3
> return ret;
> }
>
> +static int
> +scmi_clock_get_permissions(const struct scmi_protocol_handle *ph, u32 clk_id,
> + struct scmi_clock_info *clk)
> +{
> + struct scmi_xfer *t;
> + u32 perm;
> + int ret;
> +
> + ret = ph->xops->xfer_get_init(ph, CLOCK_GET_PERMISSIONS,
> + sizeof(clk_id), sizeof(perm), &t);
> + if (ret)
> + return ret;
> +
> + put_unaligned_le32(clk_id, t->tx.buf);
> +
> + ret = ph->xops->do_xfer(ph, t);
> + if (!ret) {
> + perm = get_unaligned_le32(t->rx.buf);
> +
> + clk->state_ctrl_forbidden = !(perm & CLOCK_STATE_CONTROL_ALLOWED);
> + clk->rate_ctrl_forbidden = !(perm & CLOCK_RATE_CONTROL_ALLOWED);
> + clk->parent_ctrl_forbidden = !(perm & CLOCK_PARENT_CONTROL_ALLOWED);
> + }
> +
> + ph->xops->xfer_put(ph, t);
> +
> + return ret;
> +}
> +
> static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> u32 clk_id, struct scmi_clock_info *clk,
> u32 version)
> @@ -307,6 +342,7 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> if (PROTOCOL_REV_MAJOR(version) >= 0x2)
> latency = le32_to_cpu(attr->clock_enable_latency);
> clk->enable_latency = latency ? : U32_MAX;
> + clk->attributes = attributes;
> }
>
> ph->xops->xfer_put(ph, t);
> @@ -327,6 +363,8 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> clk->rate_change_requested_notifications = true;
> if (SUPPORTS_PARENT_CLOCK(attributes))
> scmi_clock_possible_parents(ph, clk_id, clk);
> + if (SUPPORTS_GET_PERMISSIONS(attributes))
> + scmi_clock_get_permissions(ph, clk_id, clk);
> }
>
> return ret;
> @@ -499,6 +537,10 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
> struct scmi_xfer *t;
> struct scmi_clock_set_rate *cfg;
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
> +
> + if (clk->rate_ctrl_forbidden)
> + return -EACCES;
>
> ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, &t);
> if (ret)
> @@ -585,6 +627,9 @@ scmi_clock_set_parent(const struct scmi_protocol_handle *ph, u32 clk_id,
> if (parent_id >= clk->num_parents)
> return -EINVAL;
>
> + if (clk->parent_ctrl_forbidden)
> + return -EACCES;
> +
> ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_SET,
> sizeof(*cfg), 0, &t);
> if (ret)
> @@ -668,6 +713,10 @@ static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id,
> bool atomic)
> {
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
> +
> + if (clk->state_ctrl_forbidden)
> + return -EACCES;
>
> return ci->clock_config_set(ph, clk_id, CLK_STATE_ENABLE,
> NULL_OEM_TYPE, 0, atomic);
> @@ -677,6 +726,10 @@ static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id,
> bool atomic)
> {
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
> +
> + if (clk->state_ctrl_forbidden)
> + return -EACCES;
>
> return ci->clock_config_set(ph, clk_id, CLK_STATE_DISABLE,
> NULL_OEM_TYPE, 0, atomic);
> diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
> index f2f05fb42d28..ad75784b567b 100644
> --- a/include/linux/scmi_protocol.h
> +++ b/include/linux/scmi_protocol.h
> @@ -47,6 +47,9 @@ struct scmi_clock_info {
> bool rate_discrete;
> bool rate_changed_notifications;
> bool rate_change_requested_notifications;
> + bool state_ctrl_forbidden;
> + bool rate_ctrl_forbidden;
> + bool parent_ctrl_forbidden;
> union {
> struct {
> int num_rates;
> @@ -60,6 +63,7 @@ struct scmi_clock_info {
> };
> int num_parents;
> u32 *parents;
> + u32 attributes;
> };
>
> enum scmi_power_scale {
On Tue, Jan 09, 2024 at 09:06:11AM +0800, Peng Fan wrote:
> Hi Sudeep, Cristian,
>
Hi,
I have not forgot, I'll have a look this week.
Thanks,
Cristian
On Thu, Dec 07, 2023 at 05:33:44PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
Hi Peng,
a few remarks down below, but generally LGTM.
>> Subject: Re: [PATCH V2 1/2] firmware: arm_scmi: clock: implement get permissions
till now we never added a <proto>: tag just "firmware: arm_scmi:",
capitalizing the first word. (not saying that using "clock:" is bad but
since we never used till now...), as an example
firmware: arm_scmi: Implement Clock get permissions
> ARM SCMI Spec 3.2 introduces Clock Get Permission command. This patch
> is to add the support. Add three bool entries to scmi_clock_info to
> indicate the operation is forbidden or not. If the CLOCK_GET_PERMISSIONS
> command is not supported, the three bool variables will default
> set to false, otherwise they will be set according to the return result
> of CLOCK_GET_PERMISSIONS.
>
> Signed-off-by: Peng Fan <[email protected]>
> ---
>
> V2:
> Take Cristian's suggestion, https://lore.kernel.org/all/ZWiqqfQ73tezFmSk@pluto/
>
> drivers/firmware/arm_scmi/clock.c | 53 +++++++++++++++++++++++++++++++
> include/linux/scmi_protocol.h | 4 +++
> 2 files changed, 57 insertions(+)
>
> diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
> index 98511a3aa367..0e048530bea2 100644
> --- a/drivers/firmware/arm_scmi/clock.c
> +++ b/drivers/firmware/arm_scmi/clock.c
> @@ -25,8 +25,13 @@ enum scmi_clock_protocol_cmd {
> CLOCK_POSSIBLE_PARENTS_GET = 0xC,
> CLOCK_PARENT_SET = 0xD,
> CLOCK_PARENT_GET = 0xE,
> + CLOCK_GET_PERMISSIONS = 0xF,
> };
>
> +#define CLOCK_STATE_CONTROL_ALLOWED BIT(31)
> +#define CLOCK_PARENT_CONTROL_ALLOWED BIT(30)
> +#define CLOCK_RATE_CONTROL_ALLOWED BIT(29)
> +
> enum clk_state {
> CLK_STATE_DISABLE,
> CLK_STATE_ENABLE,
> @@ -46,6 +51,7 @@ struct scmi_msg_resp_clock_attributes {
> #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))
> +#define SUPPORTS_GET_PERMISSIONS(x) ((x) & BIT(1))
> u8 name[SCMI_SHORT_NAME_MAX_SIZE];
> __le32 clock_enable_latency;
> };
> @@ -281,6 +287,35 @@ static int scmi_clock_possible_parents(const struct scmi_protocol_handle *ph, u3
> return ret;
> }
>
> +static int
> +scmi_clock_get_permissions(const struct scmi_protocol_handle *ph, u32 clk_id,
> + struct scmi_clock_info *clk)
> +{
> + struct scmi_xfer *t;
> + u32 perm;
> + int ret;
> +
> + ret = ph->xops->xfer_get_init(ph, CLOCK_GET_PERMISSIONS,
> + sizeof(clk_id), sizeof(perm), &t);
> + if (ret)
> + return ret;
> +
> + put_unaligned_le32(clk_id, t->tx.buf);
> +
> + ret = ph->xops->do_xfer(ph, t);
> + if (!ret) {
> + perm = get_unaligned_le32(t->rx.buf);
> +
> + clk->state_ctrl_forbidden = !(perm & CLOCK_STATE_CONTROL_ALLOWED);
> + clk->rate_ctrl_forbidden = !(perm & CLOCK_RATE_CONTROL_ALLOWED);
> + clk->parent_ctrl_forbidden = !(perm & CLOCK_PARENT_CONTROL_ALLOWED);
> + }
> +
> + ph->xops->xfer_put(ph, t);
> +
> + return ret;
> +}
> +
> static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> u32 clk_id, struct scmi_clock_info *clk,
> u32 version)
> @@ -307,6 +342,7 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> if (PROTOCOL_REV_MAJOR(version) >= 0x2)
> latency = le32_to_cpu(attr->clock_enable_latency);
> clk->enable_latency = latency ? : U32_MAX;
> + clk->attributes = attributes;
Exposing the full attributes is NOT needed anymore now you have the bools right ?
> }
>
> ph->xops->xfer_put(ph, t);
> @@ -327,6 +363,8 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
> clk->rate_change_requested_notifications = true;
> if (SUPPORTS_PARENT_CLOCK(attributes))
> scmi_clock_possible_parents(ph, clk_id, clk);
> + if (SUPPORTS_GET_PERMISSIONS(attributes))
> + scmi_clock_get_permissions(ph, clk_id, clk);
> }
>
> return ret;
> @@ -499,6 +537,10 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
> struct scmi_xfer *t;
> struct scmi_clock_set_rate *cfg;
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
> +
This lacks a check on the provided clk_id bounds (just in case the
calling SCMI driver misbehaves)....in other protocols we have some
common internal helper to lookup a domain by id safely, it was still just
not added till today in Clock since not so much needed.
This seems not to be the case anymore, so today I posted this trivial:
https://lore.kernel.org/linux-arm-kernel/[email protected]/
Please rebase on this and just use it also on this patch like::
--->8---
diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index 51b21ce97cd5..01b372ac205f 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -549,7 +549,11 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
struct scmi_xfer *t;
struct scmi_clock_set_rate *cfg;
struct clock_info *ci = ph->get_priv(ph);
- struct scmi_clock_info *clk = ci->clk + clk_id;
+ struct scmi_clock_info *clk;
+
+ clk = scmi_clock_domain_lookup(ci, clk_id);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
if (clk->rate_ctrl_forbidden)
return -EACCES;
@@ -724,7 +728,11 @@ static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id,
bool atomic)
{
struct clock_info *ci = ph->get_priv(ph);
- struct scmi_clock_info *clk = ci->clk + clk_id;
+ struct scmi_clock_info *clk;
+
+ clk = scmi_clock_domain_lookup(ci, clk_id);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
if (clk->state_ctrl_forbidden)
return -EACCES;
@@ -737,7 +745,11 @@ static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id,
bool atomic)
{
struct clock_info *ci = ph->get_priv(ph);
- struct scmi_clock_info *clk = ci->clk + clk_id;
+ struct scmi_clock_info *clk;
+
+ clk = scmi_clock_domain_lookup(ci, clk_id);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
if (clk->state_ctrl_forbidden)
return -EACCES;
---8<-------
> + if (clk->rate_ctrl_forbidden)
> + return -EACCES;
>
> ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, &t);
> if (ret)
> @@ -585,6 +627,9 @@ scmi_clock_set_parent(const struct scmi_protocol_handle *ph, u32 clk_id,
> if (parent_id >= clk->num_parents)
> return -EINVAL;
>
> + if (clk->parent_ctrl_forbidden)
> + return -EACCES;
> +
> ret = ph->xops->xfer_get_init(ph, CLOCK_PARENT_SET,
> sizeof(*cfg), 0, &t);
> if (ret)
> @@ -668,6 +713,10 @@ static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id,
> bool atomic)
> {
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
Ditto.
> +
> + if (clk->state_ctrl_forbidden)
> + return -EACCES;
>
> return ci->clock_config_set(ph, clk_id, CLK_STATE_ENABLE,
> NULL_OEM_TYPE, 0, atomic);
> @@ -677,6 +726,10 @@ static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id,
> bool atomic)
> {
> struct clock_info *ci = ph->get_priv(ph);
> + struct scmi_clock_info *clk = ci->clk + clk_id;
Ditto.
> +
> + if (clk->state_ctrl_forbidden)
> + return -EACCES;
>
> return ci->clock_config_set(ph, clk_id, CLK_STATE_DISABLE,
> NULL_OEM_TYPE, 0, atomic);
> diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
> index f2f05fb42d28..ad75784b567b 100644
> --- a/include/linux/scmi_protocol.h
> +++ b/include/linux/scmi_protocol.h
> @@ -47,6 +47,9 @@ struct scmi_clock_info {
> bool rate_discrete;
> bool rate_changed_notifications;
> bool rate_change_requested_notifications;
> + bool state_ctrl_forbidden;
> + bool rate_ctrl_forbidden;
> + bool parent_ctrl_forbidden;
> union {
> struct {
> int num_rates;
> @@ -60,6 +63,7 @@ struct scmi_clock_info {
> };
> int num_parents;
> u32 *parents;
> + u32 attributes;
Ditto. Drop this.
Thanks,
Cristian
On Thu, Dec 07, 2023 at 05:33:45PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
> Some clocks may exported to linux, while those clocks are not allowed
> to configure by Linux. For example:
>
Hi,
> SYS_CLK1-----
> \
> --MUX--->MMC1_CLK
> /
> SYS_CLK2-----
>
> MMC1 needs set parent, so SYS_CLK1 and SYS_CLK2 are exported to Linux,
> then the clk propagation will touch SYS_CLK1 or SYS_CLK2.
> So we need bypass the failure for SYS_CLK1 or SYS_CLK2 when enable
> the clock of MMC1.
>
So I was puzzled a bit at first (as said) by the fact that here we
silently swallow the failure if the SCMI Clock cannot be disabled, BUT
then I spotted in include/linux/clk.h
/**
* clk_enable - inform the system when the clock source should be running.
* @clk: clock source
*
* If the clock can not be enabled/disabled, this should return success.
..so I suppose it is fine for the CLK framework at the end.
My next remaining question is why are you not doing the same when
(ret == -EACCES && clk->info->state_ctrl_forbidden) for atomic_ops ?
I.e. in:
clk-scmi.c::static int scmi_clk_atomic_enable(struct clk_hw *hw)
Any particular reason (beside not needing it in your particular case...)
Thanks,
Cristian
> Subject: Re: [PATCH V2 2/2] clk: scmi: support state_ctrl_forbidden
>
> On Thu, Dec 07, 2023 at 05:33:45PM +0800, Peng Fan (OSS) wrote:
> > From: Peng Fan <[email protected]>
> >
> > Some clocks may exported to linux, while those clocks are not allowed
> > to configure by Linux. For example:
> >
>
> Hi,
>
> > SYS_CLK1-----
> > \
> > --MUX--->MMC1_CLK
> > /
> > SYS_CLK2-----
> >
> > MMC1 needs set parent, so SYS_CLK1 and SYS_CLK2 are exported to Linux,
> > then the clk propagation will touch SYS_CLK1 or SYS_CLK2.
> > So we need bypass the failure for SYS_CLK1 or SYS_CLK2 when enable the
> > clock of MMC1.
> >
>
>
> So I was puzzled a bit at first (as said) by the fact that here we silently swallow
> the failure if the SCMI Clock cannot be disabled, BUT then I spotted in
> include/linux/clk.h
>
> /**
> * clk_enable - inform the system when the clock source should be
> running.
> * @clk: clock source
> *
> * If the clock can not be enabled/disabled, this should return success.
>
> ...so I suppose it is fine for the CLK framework at the end.
>
> My next remaining question is why are you not doing the same when (ret == -
> EACCES && clk->info->state_ctrl_forbidden) for atomic_ops ?
>
> I.e. in:
>
> clk-scmi.c::static int scmi_clk_atomic_enable(struct clk_hw *hw)
>
> Any particular reason (beside not needing it in your particular case...)
No particular reason, we not use atomic_ops in our case. So I am not able
to test it. I could add the same in atomic_ops in V3.
Thanks,
Peng.
>
> Thanks,
> Cristian