@@ -1705,6 +1705,39 @@ static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
return info->desc->max_msg_size;
}
+/**
+ * scmi_protocol_msg_check - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ * attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+ u32 message_id, u32 *attributes)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+ sizeof(__le32), 0, &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(message_id, t->tx.buf);
+ ret = do_xfer(ph, t);
+ if (!ret && attributes)
+ *attributes = get_unaligned_le32(t->rx.buf);
+ xfer_put(ph, t);
+
+ return ret;
+}
+
/**
* struct scmi_iterator - Iterator descriptor
* @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1846,6 +1879,7 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
int ret;
u32 flags;
u64 phys_addr;
+ u32 attributes;
u8 size;
void __iomem *addr;
struct scmi_xfer *t;
@@ -1854,6 +1888,11 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
struct scmi_msg_resp_desc_fc *resp;
const struct scmi_protocol_instance *pi = ph_to_pi(ph);
+ /* Check if the MSG_ID supports fastchannel */
+ ret = scmi_protocol_msg_check(ph, message_id, &attributes);
+ if (!ret && !MSG_SUPPORTS_FASTCHANNEL(attributes))
+ return;
+
if (!p_addr) {
ret = -EINVAL;
goto err_out;
@@ -1981,39 +2020,6 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
#endif
}
-/**
- * scmi_protocol_msg_check - Check protocol message attributes
- *
- * @ph: A reference to the protocol handle.
- * @message_id: The ID of the message to check.
- * @attributes: A parameter to optionally return the retrieved message
- * attributes, in case of Success.
- *
- * An helper to check protocol message attributes for a specific protocol
- * and message pair.
- *
- * Return: 0 on SUCCESS
- */
-static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
- u32 message_id, u32 *attributes)
-{
- int ret;
- struct scmi_xfer *t;
-
- ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
- sizeof(__le32), 0, &t);
- if (ret)
- return ret;
-
- put_unaligned_le32(message_id, t->tx.buf);
- ret = do_xfer(ph, t);
- if (!ret && attributes)
- *attributes = get_unaligned_le32(t->rx.buf);
- xfer_put(ph, t);
-
- return ret;
-}
-
static const struct scmi_proto_helpers_ops helpers_ops = {
.extended_name_get = scmi_common_extended_name_get,
.get_max_msg_size = scmi_common_get_max_msg_size,
@@ -31,6 +31,8 @@
#define SCMI_PROTOCOL_VENDOR_BASE 0x80
+#define MSG_SUPPORTS_FASTCHANNEL(x) ((x) & BIT(0))
+
enum scmi_common_cmd {
PROTOCOL_VERSION = 0x0,
PROTOCOL_ATTRIBUTES = 0x1,
Currently the perf and powercap protocol relies on the protocol domain attributes, which just ensures that one fastchannel per domain, before instantiating fastchannels for all possible message-ids. Fix this by ensuring that each message-id supports fastchannel before initialization. Reported-by: Johan Hovold <johan+linaro@kernel.org> Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/ Fixes: 6f9ea4dabd2d ("firmware: arm_scmi: Generalize the fast channel support") Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Johan Hovold <johan+linaro@kernel.org> --- v3: * Pick up R-b, T-b from the list. * Move scmi_protocol_msg_check to the top [Sudeep] drivers/firmware/arm_scmi/driver.c | 72 +++++++++++++++------------ drivers/firmware/arm_scmi/protocols.h | 2 + 2 files changed, 41 insertions(+), 33 deletions(-)