path: root/drivers/net/wireless/iwlwifi/iwl-trans.h

/******************************************************************************
 *
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 *  Intel Linux Wireless <ilw@linux.intel.com>
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#ifndef __iwl_trans_h__
#define __iwl_trans_h__

#include <linux/ieee80211.h>
#include <linux/mm.h> /* for page_address */
#include <linux/lockdep.h>

#include "iwl-debug.h"
#include "iwl-config.h"
#include "iwl-fw.h"
#include "iwl-op-mode.h"

/**
 * DOC: Transport layer - what is it ?
 *
 * The tranport layer is the layer that deals with the HW directly. It provides
 * an abstraction of the underlying HW to the upper layer. The transport layer
 * doesn't provide any policy, algorithm or anything of this kind, but only
 * mechanisms to make the HW do something.It is not completely stateless but
 * close to it.
 * We will have an implementation for each different supported bus.
 */

/**
 * DOC: Life cycle of the transport layer
 *
 * The transport layer has a very precise life cycle.
 *
 *	1) A helper function is called during the module initialization and
 *	   registers the bus driver's ops with the transport's alloc function.
 *	2) Bus's probe calls to the transport layer's allocation functions.
 *	   Of course this function is bus specific.
 *	3) This allocation functions will spawn the upper layer which will
 *	   register mac80211.
 *
 *	4) At some point (i.e. mac80211's start call), the op_mode will call
 *	   the following sequence:
 *	   start_hw
 *	   start_fw
 *
 *	5) Then when finished (or reset):
 *	   stop_device
 *
 *	6) Eventually, the free function will be called.
 */

/**
 * DOC: Host command section
 *
 * A host command is a commaned issued by the upper layer to the fw. There are
 * several versions of fw that have several APIs. The transport layer is
 * completely agnostic to these differences.
 * The transport does provide helper functionnality (i.e. SYNC / ASYNC mode),
 */
#define SEQ_TO_QUEUE(s)	(((s) >> 8) & 0x1f)
#define QUEUE_TO_SEQ(q)	(((q) & 0x1f) << 8)
#define SEQ_TO_INDEX(s)	((s) & 0xff)
#define INDEX_TO_SEQ(i)	((i) & 0xff)
#define SEQ_RX_FRAME	cpu_to_le16(0x8000)

/**
 * struct iwl_cmd_header
 *
 * This header format appears in the beginning of each command sent from the
 * driver, and each response/notification received from uCode.
 */
struct iwl_cmd_header {
	u8 cmd;		/* Command ID:  REPLY_RXON, etc. */
	u8 flags;	/* 0:5 reserved, 6 abort, 7 internal */
	/*
	 * The driver sets up the sequence number to values of its choosing.
	 * uCode does not use this value, but passes it back to the driver
	 * when sending the response to each driver-originated command, so
	 * the driver can match the response to the command.  Since the values
	 * don't get used by uCode, the driver may set up an arbitrary format.
	 *
	 * There is one exception:  uCode sets bit 15 when it originates
	 * the response/notification, i.e. when the response/notification
	 * is not a direct response to a command sent by the driver.  For
	 * example, uCode issues REPLY_RX when it sends a received frame
	 * to the driver; it is not a direct response to any driver command.
	 *
	 * The Linux driver uses the following format:
	 *
	 *  0:7		tfd index - position within TX queue
	 *  8:12	TX queue id
	 *  13:14	reserved
	 *  15		unsolicited RX or uCode-originated notification
	 */
	__le16 sequence;
} __packed;

/* iwl_cmd_header flags value */
#define IWL_CMD_FAILED_MSK 0x40


#define FH_RSCSR_FRAME_SIZE_MSK		0x00003FFF	/* bits 0-13 */
#define FH_RSCSR_FRAME_INVALID		0x55550000
#define FH_RSCSR_FRAME_ALIGN		0x40

struct iwl_rx_packet {
	/*
	 * The first 4 bytes of the RX frame header contain both the RX frame
	 * size and some flags.
	 * Bit fields:
	 * 31:    flag flush RB request
	 * 30:    flag ignore TC (terminal counter) request
	 * 29:    flag fast IRQ request
	 * 28-14: Reserved
	 * 13-00: RX frame size
	 */
	__le32 len_n_flags;
	struct iwl_cmd_header hdr;
	u8 data[];
} __packed;

/**
 * enum CMD_MODE - how to send the host commands ?
 *
 * @CMD_SYNC: The caller will be stalled until the fw responds to the command
 * @CMD_ASYNC: Return right away and don't wait for the response
 * @CMD_WANT_SKB: valid only with CMD_SYNC. The caller needs the buffer of the
 *	response. The caller needs to call iwl_free_resp when done.
 */
enum CMD_MODE {
	CMD_SYNC		= 0,
	CMD_ASYNC		= BIT(0),
	CMD_WANT_SKB		= BIT(1),
	CMD_SEND_IN_RFKILL	= BIT(2),
};

#define DEF_CMD_PAYLOAD_SIZE 320

/**
 * struct iwl_device_cmd
 *
 * For allocation of the command and tx queues, this establishes the overall
 * size of the largest command we send to uCode, except for commands that
 * aren't fully copied and use other TFD space.
 */
struct iwl_device_cmd {
	struct iwl_cmd_header hdr;	/* uCode API */
	u8 payload[DEF_CMD_PAYLOAD_SIZE];
} __packed;

#define TFD_MAX_PAYLOAD_SIZE (sizeof(struct iwl_device_cmd))

/*
 * number of transfer buffers (fragments) per transmit frame descriptor;
 * this is just the driver's idea, the hardware supports 20
 */
#define IWL_MAX_CMD_TBS_PER_TFD	2

/**
 * struct iwl_hcmd_dataflag - flag for each one of the chunks of the command
 *
 * @IWL_HCMD_DFL_NOCOPY: By default, the command is copied to the host command's
 *	ring. The transport layer doesn't map the command's buffer to DMA, but
 *	rather copies it to a previously allocated DMA buffer. This flag tells
 *	the transport layer not to copy the command, but to map the existing
 *	buffer (that is passed in) instead. This saves the memcpy and allows
 *	commands that are bigger than the fixed buffer to be submitted.
 *	Note that a TFD entry after a NOCOPY one cannot be a normal copied one.
 * @IWL_HCMD_DFL_DUP: Only valid without NOCOPY, duplicate the memory for this
 *	chunk internally and free it again after the command completes. This
 *	can (currently) be used only once per command.
 *	Note that a TFD entry after a DUP one cannot be a normal copied one.
 */
enum iwl_hcmd_dataflag {
	IWL_HCMD_DFL_NOCOPY	= BIT(0),
	IWL_HCMD_DFL_DUP	= BIT(1),
};

/**
 * struct iwl_host_cmd - Host command to the uCode
 *
 * @data: array of chunks that composes the data of the host command
 * @resp_pkt: response packet, if %CMD_WANT_SKB was set
 * @_rx_page_order: (internally used to free response packet)
 * @_rx_page_addr: (internally used to free response packet)
 * @handler_status: return value of the handler of the command
 *	(put in setup_rx_handlers) - valid for SYNC mode only
 * @flags: can be CMD_*
 * @len: array of the lengths of the chunks in data
 * @dataflags: IWL_HCMD_DFL_*
 * @id: id of the host command
 */
struct iwl_host_cmd {
	const void *data[IWL_MAX_CMD_TBS_PER_TFD];
	struct iwl_rx_packet *resp_pkt;
	unsigned long _rx_page_addr;
	u32 _rx_page_order;
	int handler_status;

	u32 flags;
	u16 len[IWL_MAX_CMD_TBS_PER_TFD];
	u8 dataflags[IWL_MAX_CMD_TBS_PER_TFD];
	u8 id;
};

static inline void iwl_free_resp(struct iwl_host_cmd *cmd)
{
	free_pages(cmd->_rx_page_addr, cmd->_rx_page_order);
}

struct iwl_rx_cmd_buffer {
	struct page *_page;
	int _offset;
	bool _page_stolen;
	u32 _rx_page_order;
	unsigned int truesize;
};

static inline void *rxb_addr(struct iwl_rx_cmd_buffer *r)
{
	return (void *)((unsigned long)page_address(r->_page) + r->_offset);
}

static inline int rxb_offset(struct iwl_rx_cmd_buffer *r)
{
	return r->_offset;
}

static inline struct page *rxb_steal_page(struct iwl_rx_cmd_buffer *r)
{
	r->_page_stolen = true;
	get_page(r->_page);
	return r->_page;
}

static inline void iwl_free_rxb(struct iwl_rx_cmd_buffer *r)
{
	__free_pages(r->_page, r->_rx_page_order);
}

#define MAX_NO_RECLAIM_CMDS	6

#define IWL_MASK(lo, hi) ((1 << (hi)) | ((1 << (hi)) - (1 << (lo))))

/*
 * Maximum number of HW queues the transport layer
 * currently supports
 */
#define IWL_MAX_HW_QUEUES		32
#define IWL_MAX_TID_COUNT	8
#define IWL_FRAME_LIMIT	64

/**
 * enum iwl_wowlan_status - WoWLAN image/device status
 * @IWL_D3_STATUS_ALIVE: firmware is still running after resume
 * @IWL_D3_STATUS_RESET: device was reset while suspended
 */
enum iwl_d3_status {
	IWL_D3_STATUS_ALIVE,
	IWL_D3_STATUS_RESET,
};

/**
 * enum iwl_trans_status: transport status flags
 * @STATUS_SYNC_HCMD_ACTIVE: a SYNC command is being processed
 * @STATUS_DEVICE_ENABLED: APM is enabled
 * @STATUS_TPOWER_PMI: the device might be asleep (need to wake it up)
 * @STATUS_INT_ENABLED: interrupts are enabled
 * @STATUS_RFKILL: the HW RFkill switch is in KILL position
 * @STATUS_FW_ERROR: the fw is in error state
 */
enum iwl_trans_status {
	STATUS_SYNC_HCMD_ACTIVE,
	STATUS_DEVICE_ENABLED,
	STATUS_TPOWER_PMI,
	STATUS_INT_ENABLED,
	STATUS_RFKILL,
	STATUS_FW_ERROR,
};

/**
 * struct iwl_trans_config - transport configuration
 *
 * @op_mode: pointer to the upper layer.
 * @cmd_queue: the index of the command queue.
 *	Must be set before start