linux-zen-desktop/drivers/net/wireless/intel/iwlwifi/mei/iwl-mei.h

530 lines
19 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2021 Intel Corporation
*/
#ifndef __iwl_mei_h__
#define __iwl_mei_h__
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/ieee80211.h>
/**
* DOC: Introduction
*
* iwlmei is the kernel module that is in charge of the communication between
* the iwlwifi driver and the CSME firmware's WLAN driver. This communication
* uses the SAP protocol defined in another file.
* iwlwifi can request or release ownership on the WiFi device through iwlmei.
* iwlmei may notify iwlwifi about certain events: what filter iwlwifi should
* use to passthrough inbound packets to the CSME firmware for example. iwlmei
* may also use iwlwifi to send traffic. This means that we need communication
* from iwlmei to iwlwifi and the other way around.
*/
/**
* DOC: Life cycle
*
* iwlmei exports symbols that are needed by iwlwifi so that iwlmei will always
* be loaded when iwlwifi is alive. iwlwifi registers itself to iwlmei and
* provides the pointers to the functions that iwlmei calls whenever needed.
* iwlwifi calls iwlmei through direct and context-free function calls.
* It is assumed that only one device is accessible to the CSME firmware and
* under the scope of iwlmei so that it is valid not to have any context passed
* to iwlmei's functions.
*
* There are cases in which iwlmei can't access the CSME firmware, because the
* CSME firmware is undergoing a reset, or the mei bus decided to unbind the
* device. In those cases, iwlmei will need not to send requests over the mei
* bus. Instead, it needs to cache the requests from iwlwifi and fulfill them
* when the mei bus is available again.
*
* iwlmei can call iwlwifi as long as iwlwifi is registered to iwlmei. When
* iwlwifi goes down (the PCI device is unbound, or the iwlwifi is unloaded)
* iwlwifi needs to unregister from iwlmei.
*/
/**
* DOC: Memory layout
*
* Since iwlwifi calls iwlmei without any context, iwlmei needs to hold a
* global pointer to its data (which is in the mei client device's private
* data area). If there was no bind on the mei bus, this pointer is NULL and
* iwlmei knows not access to the CSME firmware upon requests from iwlwifi.
*
* iwlmei needs to cache requests from iwlwifi when there is no mei client
* device available (when iwlmei has been removed from the mei bus). In this
* case, all iwlmei's data that resides in the mei client device's private data
* area is unavailable. For this specific case, a separate caching area is
* needed.
*/
/**
* DOC: Concurrency
*
* iwlwifi can call iwlmei at any time. iwlmei will take care to synchronize
* the calls from iwlwifi with its internal flows. iwlwifi must not call iwlmei
* in flows that cannot sleep. Moreover, iwlwifi must not call iwlmei in flows
* that originated from iwlmei.
*/
/**
* DOC: Probe and remove from mei bus driver
*
* When the mei bus driver enumerates its devices, it calls the iwlmei's probe
* function which will send the %SAP_ME_MSG_START message. The probe completes
* before the response (%SAP_ME_MSG_START_OK) is received. This response will
* be handle by the Rx path. Once it arrives, the connection to the CSME
* firmware is considered established and iwlwifi's requests can be treated
* against the CSME firmware.
*
* When the mei bus driver removes the device, iwlmei loses all the data that
* was attached to the mei client device. It clears the global pointer to the
* mei client device since it is not available anymore. This will cause all the
* requests coming from iwlwifi to be cached. This flow takes the global mutex
* to be synchronized with all the requests coming from iwlwifi.
*/
/**
* DOC: Driver load when CSME owns the device
*
* When the driver (iwlwifi) is loaded while CSME owns the device,
* it'll ask CSME to release the device through HW registers. CSME
* will release the device only in the case that there is no connection
* through the mei bus. If there is a mei bus connection, CSME will refuse
* to release the ownership on the device through the HW registers. In that
* case, iwlwifi must first request ownership using the SAP protocol.
*
* Once iwlwifi will request ownership through the SAP protocol, CSME will
* grant the ownership on the device through the HW registers as well.
* In order to request ownership over SAP, we first need to have an interface
* which means that we need to register to mac80211.
* This can't happen before we get the NVM that contains all the capabilities
* of the device. Reading the NVM usually requires the load the firmware, but
* this is impossible as long as we don't have ownership on the device.
* In order to solve this chicken and egg problem, the host driver can get
* the NVM through CSME which owns the device. It can send
* %SAP_MSG_NOTIF_GET_NVM, which will be replied by %SAP_MSG_NOTIF_NVM with
* the NVM's content that the host driver needs.
*/
/**
* DOC: CSME behavior regarding the ownership requests
*
* The ownership requests from the host can come in two different ways:
* - the HW registers in iwl_pcie_set_hw_ready
* - using the Software Arbitration Protocol (SAP)
*
* The host can ask CSME who owns the device with %SAP_MSG_NOTIF_WHO_OWNS_NIC,
* and it can request ownership with %SAP_MSG_NOTIF_HOST_ASKS_FOR_NIC_OWNERSHIP.
* The host will first use %SAP_MSG_NOTIF_WHO_OWNS_NIC to know what state
* CSME is in. In case CSME thinks it owns the device, the host can ask for
* ownership with %SAP_MSG_NOTIF_HOST_ASKS_FOR_NIC_OWNERSHIP.
*
* Here the table that describes CSME's behavior upon ownership request:
*
* +-------------------+------------+--------------+-----------------------------+------------+
* | State | HW reg bit | Reply for | Event | HW reg bit |
* | | before | WHO_OWNS_NIC | | after |
* +===================+============+==============+=============================+============+
* | WiAMT not | 0 | Host | HW register or | 0 |
* | operational | Host owner | | HOST_ASKS_FOR_NIC_OWNERSHIP | Host owner |
* +-------------------+------------+--------------+-----------------------------+------------+
* | Operational & | 1 | N/A | HW register | 0 |
* | SAP down & | CSME owner | | | Host owner |
* | no session active | | | | |
* +-------------------+------------+--------------+-----------------------------+------------+
* | Operational & | 1 | CSME | HW register | 1 |
* | SAP up | CSME owner | | | CSME owner |
* +-------------------+------------+--------------+-----------------------------+------------+
* | Operational & | 1 | CSME | HOST_ASKS_FOR_NIC_OWNERSHIP | 0 |
* | SAP up | CSME owner | | | Host owner |
* +-------------------+------------+--------------+-----------------------------+------------+
*/
/**
* DOC: Driver load when CSME is associated and a session is active
*
* A "session" is active when CSME is associated to an access point and the
* link is used to attach a remote driver or to control the system remotely.
* When a session is active, we want to make sure it won't disconnect when we
* take ownership on the device.
* In this case, the driver can get the device, but it'll need to make
* sure that it'll connect to the exact same AP (same BSSID).
* In order to do so, CSME will send the connection parameters through
* SAP and then the host can check if it can connect to this same AP.
* If yes, it can request ownership through SAP and connect quickly without
* scanning all the channels, but just probing the AP on the channel that
* CSME was connected to.
* In order to signal this specific scenario to iwlwifi, iwlmei will
* immediately require iwlwifi to report RF-Kill to the network stack. This
* RF-Kill will prevent the stack from getting the device, and it has a reason
* that tells the userspace that the device is in RF-Kill because it is not
* owned by the host. Once the userspace has configured the right profile,
* it'll be able to let iwlmei know that it can request ownership over SAP
* which will remove the RF-Kill, and finally allow the host to connect.
* The host has then 3 seconds to connect (including DHCP). Had the host
* failed to connect within those 3 seconds, CSME will take the device back.
*/
/**
* DOC: Datapath
*
* CSME can transmit packets, through the netdev that it gets from the wifi
* driver. It'll send packet in the 802.3 format and simply call
* dev_queue_xmit.
*
* For Rx, iwlmei registers a Rx handler that it attaches to the netdev. iwlmei
* may catch packets and send them to CSME, it can then either drop them so
* that they are invisible to user space, or let them go the user space.
*
* Packets transmitted by the user space do not need to be forwarded to CSME
* with the exception of the DHCP request. In order to know what IP is used
* by the user space, CSME needs to get the DHCP request. See
* iwl_mei_tx_copy_to_csme().
*/
/**
* enum iwl_mei_nvm_caps - capabilities for MEI NVM
* @MEI_NVM_CAPS_LARI_SUPPORT: Lari is supported
* @MEI_NVM_CAPS_11AX_SUPPORT: 11AX is supported
*/
enum iwl_mei_nvm_caps {
MEI_NVM_CAPS_LARI_SUPPORT = BIT(0),
MEI_NVM_CAPS_11AX_SUPPORT = BIT(1),
};
/**
* struct iwl_mei_nvm - used to pass the NVM from CSME
* @hw_addr: The MAC address
* @n_hw_addrs: The number of MAC addresses
* @reserved: For alignment.
* @radio_cfg: The radio configuration.
* @caps: See &enum iwl_mei_nvm_caps.
* @nvm_version: The version of the NVM.
* @channels: The data for each channel.
*
* If a field is added, it must correspond to the SAP structure.
*/
struct iwl_mei_nvm {
u8 hw_addr[ETH_ALEN];
u8 n_hw_addrs;
u8 reserved;
u32 radio_cfg;
u32 caps;
u32 nvm_version;
u32 channels[110];
};
/**
* enum iwl_mei_pairwise_cipher - cipher for UCAST key
* @IWL_MEI_CIPHER_NONE: none
* @IWL_MEI_CIPHER_TKIP: tkip
* @IWL_MEI_CIPHER_CCMP: ccmp
* @IWL_MEI_CIPHER_GCMP: gcmp
* @IWL_MEI_CIPHER_GCMP_256: gcmp 256
*
* Note that those values are dictated by the CSME firmware API (see sap.h)
*/
enum iwl_mei_pairwise_cipher {
IWL_MEI_CIPHER_NONE = 0,
IWL_MEI_CIPHER_TKIP = 2,
IWL_MEI_CIPHER_CCMP = 4,
IWL_MEI_CIPHER_GCMP = 8,
IWL_MEI_CIPHER_GCMP_256 = 9,
};
/**
* enum iwl_mei_akm_auth - a combination of AKM and AUTH method
* @IWL_MEI_AKM_AUTH_OPEN: No encryption
* @IWL_MEI_AKM_AUTH_RSNA: 1X profile
* @IWL_MEI_AKM_AUTH_RSNA_PSK: PSK profile
* @IWL_MEI_AKM_AUTH_SAE: SAE profile
*
* Note that those values are dictated by the CSME firmware API (see sap.h)
*/
enum iwl_mei_akm_auth {
IWL_MEI_AKM_AUTH_OPEN = 0,
IWL_MEI_AKM_AUTH_RSNA = 6,
IWL_MEI_AKM_AUTH_RSNA_PSK = 7,
IWL_MEI_AKM_AUTH_SAE = 9,
};
/**
* struct iwl_mei_conn_info - connection info
* @lp_state: link protection state
* @auth_mode: authentication mode
* @ssid_len: the length of SSID
* @ssid: the SSID
* @pairwise_cipher: the cipher used for unicast packets
* @channel: the associated channel
* @band: the associated band
* @bssid: the BSSID
*/
struct iwl_mei_conn_info {
u8 lp_state;
u8 auth_mode;
u8 ssid_len;
u8 channel;
u8 band;
u8 pairwise_cipher;
u8 bssid[ETH_ALEN];
u8 ssid[IEEE80211_MAX_SSID_LEN];
};
/**
* struct iwl_mei_colloc_info - collocated AP info
* @channel: the channel of the collocated AP
* @bssid: the BSSID of the collocated AP
*/
struct iwl_mei_colloc_info {
u8 channel;
u8 bssid[ETH_ALEN];
};
/*
* struct iwl_mei_ops - driver's operations called by iwlmei
* Operations will not be called more than once concurrently.
* It's not allowed to call iwlmei functions from this context.
*
* @me_conn_status: provide information about CSME's current connection.
* @rfkill: called when the wifi driver should report a change in the rfkill
* status.
* @roaming_forbidden: indicates whether roaming is forbidden.
* @sap_connected: indicate that SAP is now connected. Will be called in case
* the wifi driver registered to iwlmei before SAP connection succeeded or
* when the SAP connection is re-established.
* @nic_stolen: this means that device is no longer available. The device can
* still be used until the callback returns.
*/
struct iwl_mei_ops {
void (*me_conn_status)(void *priv,
const struct iwl_mei_conn_info *conn_info);
void (*rfkill)(void *priv, bool blocked);
void (*roaming_forbidden)(void *priv, bool forbidden);
void (*sap_connected)(void *priv);
void (*nic_stolen)(void *priv);
};
#if IS_ENABLED(CONFIG_IWLMEI)
/**
* iwl_mei_is_connected() - is the connection to the CSME firmware established?
*
* Return: true if we have a SAP connection
*/
bool iwl_mei_is_connected(void);
/**
* iwl_mei_get_nvm() - returns the NVM for the device
*
* It is the caller's responsibility to free the memory returned
* by this function.
* This function blocks (sleeps) until the NVM is ready.
*
* Return: the NVM as received from CSME
*/
struct iwl_mei_nvm *iwl_mei_get_nvm(void);
/**
* iwl_mei_get_ownership() - request ownership
*
* This function blocks until ownership is granted or timeout expired.
*
* Return: 0 in case we could get ownership on the device
*/
int iwl_mei_get_ownership(void);
/**
* iwl_mei_set_rfkill_state() - set SW and HW RF kill states
* @hw_rfkill: HW RF kill state.
* @sw_rfkill: SW RF kill state.
*
* This function must be called when SW RF kill is issued by the user.
*/
void iwl_mei_set_rfkill_state(bool hw_rfkill, bool sw_rfkill);
/**
* iwl_mei_set_nic_info() - set mac address
* @mac_address: mac address to set
* @nvm_address: NVM mac address to set
*
* This function must be called upon mac address change.
*/
void iwl_mei_set_nic_info(const u8 *mac_address, const u8 *nvm_address);
/**
* iwl_mei_set_country_code() - set new country code
* @mcc: the new applied MCC
*
* This function must be called upon country code update
*/
void iwl_mei_set_country_code(u16 mcc);
/**
* iwl_mei_set_power_limit() - set TX power limit
* @power_limit: pointer to an array of 10 elements (le16) represents the power
* restrictions per chain.
*
* This function must be called upon power restrictions change
*/
void iwl_mei_set_power_limit(const __le16 *power_limit);
/**
* iwl_mei_register() - register the wifi driver to iwlmei
* @priv: a pointer to the wifi driver's context. Cannot be NULL.
* @ops: the ops structure.
*
* Return: 0 unless something went wrong. It is illegal to call any
* other API function before this function is called and succeeds.
*
* Only one wifi driver instance (wifi device instance really)
* can register at a time.
*/
int iwl_mei_register(void *priv, const struct iwl_mei_ops *ops);
/**
* iwl_mei_start_unregister() - unregister the wifi driver from iwlmei
*
* From this point on, iwlmei will not used the callbacks provided by
* the driver, but the device is still usable.
*/
void iwl_mei_start_unregister(void);
/**
* iwl_mei_unregister_complete() - complete the unregistration
*
* Must be called after iwl_mei_start_unregister. When this function returns,
* the device is owned by CSME.
*/
void iwl_mei_unregister_complete(void);
/**
* iwl_mei_set_netdev() - sets the netdev for Tx / Rx.
* @netdev: the net_device
*
* The caller should set the netdev to a non-NULL value when the
* interface is added. Packets might be sent to the driver immediately
* afterwards.
* The caller should set the netdev to NULL when the interface is removed.
* This function will call synchronize_net() after setting the netdev to NULL.
* Only when this function returns, can the caller assume that iwlmei will
* no longer inject packets into the netdev's Tx path.
*
* Context: This function can sleep and assumes rtnl_lock is taken.
* The netdev must be set to NULL before iwl_mei_start_unregister() is called.
*/
void iwl_mei_set_netdev(struct net_device *netdev);
/**
* iwl_mei_tx_copy_to_csme() - must be called for each packet sent by
* the wifi driver.
* @skb: the skb sent
* @ivlen: the size of the IV that needs to be skipped after the MAC and
* before the SNAP header.
*
* This function doesn't take any lock, it simply tries to catch DHCP
* packets sent by the wifi driver. If the packet is a DHCP packet, it
* will send it to CSME. This function must not be called for virtual
* interfaces that are not monitored by CSME, meaning it must be called
* only for packets transmitted by the netdevice that was registered
* with iwl_mei_set_netdev().
*/
void iwl_mei_tx_copy_to_csme(struct sk_buff *skb, unsigned int ivlen);
/**
* iwl_mei_host_associated() - must be called when iwlwifi associated.
* @conn_info: pointer to the connection info structure.
* @colloc_info: pointer to the collocated AP info. This is relevant only in
* case of UHB associated AP, otherwise set to NULL.
*/
void iwl_mei_host_associated(const struct iwl_mei_conn_info *conn_info,
const struct iwl_mei_colloc_info *colloc_info);
/**
* iwl_mei_host_disassociated() - must be called when iwlwifi disassociated.
*/
void iwl_mei_host_disassociated(void);
/**
* iwl_mei_device_state() - must be called when the device changes up/down state
* @up: true if the device is up, false otherwise.
*/
void iwl_mei_device_state(bool up);
/**
* iwl_mei_pldr_req() - must be called before loading the fw
*
* Return: 0 if the PLDR flow was successful and the fw can be loaded, negative
* value otherwise.
*/
int iwl_mei_pldr_req(void);
/**
* iwl_mei_alive_notif() - must be called when alive notificaiton is received
* @success: true if received alive notification, false if waiting for the
* notificaiton timed out.
*/
void iwl_mei_alive_notif(bool success);
#else
static inline bool iwl_mei_is_connected(void)
{ return false; }
static inline struct iwl_mei_nvm *iwl_mei_get_nvm(void)
{ return NULL; }
static inline int iwl_mei_get_ownership(void)
{ return 0; }
static inline void iwl_mei_set_rfkill_state(bool hw_rfkill, bool sw_rfkill)
{}
static inline void iwl_mei_set_nic_info(const u8 *mac_address, const u8 *nvm_address)
{}
static inline void iwl_mei_set_country_code(u16 mcc)
{}
static inline void iwl_mei_set_power_limit(__le16 *power_limit)
{}
static inline int iwl_mei_register(void *priv,
const struct iwl_mei_ops *ops)
{ return 0; }
static inline void iwl_mei_start_unregister(void)
{}
static inline void iwl_mei_unregister_complete(void)
{}
static inline void iwl_mei_set_netdev(struct net_device *netdev)
{}
static inline void iwl_mei_tx_copy_to_csme(struct sk_buff *skb,
unsigned int ivlen)
{}
static inline void iwl_mei_host_associated(const struct iwl_mei_conn_info *conn_info,
const struct iwl_mei_colloc_info *colloc_info)
{}
static inline void iwl_mei_host_disassociated(void)
{}
static inline void iwl_mei_device_state(bool up)
{}
static inline int iwl_mei_pldr_req(void)
{ return 0; }
static inline void iwl_mei_alive_notif(bool success)
{}
#endif /* CONFIG_IWLMEI */
#endif /* __iwl_mei_h__ */