From 8b0a8165cdad0f4133837d753649ef4682e42c3b Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 7 Aug 2024 15:11:40 +0200 Subject: Merging upstream version 6.9.7. Signed-off-by: Daniel Baumann --- drivers/firmware/arm_scmi/driver.c | 104 ++++++++++++++++++++++++++++++++++--- 1 file changed, 98 insertions(+), 6 deletions(-) (limited to 'drivers/firmware/arm_scmi/driver.c') diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 3ea64b22cf..2709598f30 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -86,6 +86,12 @@ struct scmi_xfers_info { * @users: A refcount to track effective users of this protocol. * @priv: Reference for optional protocol private data. * @version: Protocol version supported by the platform as detected at runtime. + * @negotiated_version: When the platform supports a newer protocol version, + * the agent will try to negotiate with the platform the + * usage of the newest version known to it, since + * backward compatibility is NOT automatically assured. + * This field is NON-zero when a successful negotiation + * has completed. * @ph: An embedded protocol handle that will be passed down to protocol * initialization code to identify this instance. * @@ -99,6 +105,7 @@ struct scmi_protocol_instance { refcount_t users; void *priv; unsigned int version; + unsigned int negotiated_version; struct scmi_protocol_handle ph; }; @@ -1617,7 +1624,7 @@ static void scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph, u8 describe_id, u32 message_id, u32 valid_size, u32 domain, void __iomem **p_addr, - struct scmi_fc_db_info **p_db) + struct scmi_fc_db_info **p_db, u32 *rate_limit) { int ret; u32 flags; @@ -1661,6 +1668,9 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph, goto err_xfer; } + if (rate_limit) + *rate_limit = le32_to_cpu(resp->rate_limit) & GENMASK(19, 0); + phys_addr = le32_to_cpu(resp->chan_addr_low); phys_addr |= (u64)le32_to_cpu(resp->chan_addr_high) << 32; addr = devm_ioremap(ph->dev, phys_addr, size); @@ -1754,10 +1764,44 @@ 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, .iter_response_init = scmi_iterator_init, .iter_response_run = scmi_iterator_run, + .protocol_msg_check = scmi_protocol_msg_check, .fastchannel_init = scmi_common_fastchannel_init, .fastchannel_db_ring = scmi_common_fastchannel_db_ring, }; @@ -1781,6 +1825,44 @@ scmi_revision_area_get(const struct scmi_protocol_handle *ph) return pi->handle->version; } +/** + * scmi_protocol_version_negotiate - Negotiate protocol version + * + * @ph: A reference to the protocol handle. + * + * An helper to negotiate a protocol version different from the latest + * advertised as supported from the platform: on Success backward + * compatibility is assured by the platform. + * + * Return: 0 on Success + */ +static int scmi_protocol_version_negotiate(struct scmi_protocol_handle *ph) +{ + int ret; + struct scmi_xfer *t; + struct scmi_protocol_instance *pi = ph_to_pi(ph); + + /* At first check if NEGOTIATE_PROTOCOL_VERSION is supported ... */ + ret = scmi_protocol_msg_check(ph, NEGOTIATE_PROTOCOL_VERSION, NULL); + if (ret) + return ret; + + /* ... then attempt protocol version negotiation */ + ret = xfer_get_init(ph, NEGOTIATE_PROTOCOL_VERSION, + sizeof(__le32), 0, &t); + if (ret) + return ret; + + put_unaligned_le32(pi->proto->supported_version, t->tx.buf); + ret = do_xfer(ph, t); + if (!ret) + pi->negotiated_version = pi->proto->supported_version; + + xfer_put(ph, t); + + return ret; +} + /** * scmi_alloc_init_protocol_instance - Allocate and initialize a protocol * instance descriptor. @@ -1853,11 +1935,21 @@ scmi_alloc_init_protocol_instance(struct scmi_info *info, devres_close_group(handle->dev, pi->gid); dev_dbg(handle->dev, "Initialized protocol: 0x%X\n", pi->proto->id); - if (pi->version > proto->supported_version) - dev_warn(handle->dev, - "Detected UNSUPPORTED higher version 0x%X for protocol 0x%X." - "Backward compatibility is NOT assured.\n", - pi->version, pi->proto->id); + if (pi->version > proto->supported_version) { + ret = scmi_protocol_version_negotiate(&pi->ph); + if (!ret) { + dev_info(handle->dev, + "Protocol 0x%X successfully negotiated version 0x%X\n", + proto->id, pi->negotiated_version); + } else { + dev_warn(handle->dev, + "Detected UNSUPPORTED higher version 0x%X for protocol 0x%X.\n", + pi->version, pi->proto->id); + dev_warn(handle->dev, + "Trying version 0x%X. Backward compatibility is NOT assured.\n", + pi->proto->supported_version); + } + } return pi; -- cgit v1.2.3