diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-4965-hw.h | 268 | ||||
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-prph.h | 14 | ||||
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl4965-base.c | 2 |
3 files changed, 272 insertions, 12 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965-hw.h b/drivers/net/wireless/iwlwifi/iwl-4965-hw.h index b548b7979b42..d5d418e61923 100644 --- a/drivers/net/wireless/iwlwifi/iwl-4965-hw.h +++ b/drivers/net/wireless/iwlwifi/iwl-4965-hw.h @@ -1554,33 +1554,285 @@ enum { IWL_FH_TSSR_TX_STATUS_REG_BIT_NO_PEND_REQ(_chnl)) +/********************* START TX SCHEDULER *************************************/ + +/** + * 4965 Tx Scheduler + * + * The Tx Scheduler selects the next frame to be transmitted, chosing TFDs + * (Transmit Frame Descriptors) from up to 16 circular Tx queues resident in + * host DRAM. It steers each frame's Tx command (which contains the frame + * data) into one of up to 7 prioritized Tx DMA FIFO channels within the + * device. A queue maps to only one (selectable by driver) Tx DMA channel, + * but one DMA channel may take input from several queues. + * + * Tx DMA channels have dedicated purposes. For 4965, they are used as follows: + * + * 0 -- EDCA BK (background) frames, lowest priority + * 1 -- EDCA BE (best effort) frames, normal priority + * 2 -- EDCA VI (video) frames, higher priority + * 3 -- EDCA VO (voice) and management frames, highest priority + * 4 -- Commands (e.g. RXON, etc.) + * 5 -- HCCA short frames + * 6 -- HCCA long frames + * 7 -- not used by driver (device-internal only) + * + * Driver should normally map queues 0-6 to Tx DMA/FIFO channels 0-6. + * In addition, driver can map queues 7-15 to Tx DMA/FIFO channels 0-3 to + * support 11n aggregation via EDCA DMA channels. + * + * The driver sets up each queue to work in one of two modes: + * + * 1) Scheduler-Ack, in which the scheduler automatically supports a + * block-ack (BA) window of up to 64 TFDs. In this mode, each queue + * contains TFDs for a unique combination of Recipient Address (RA) + * and Traffic Identifier (TID), that is, traffic of a given + * Quality-Of-Service (QOS) priority, destined for a single station. + * + * In scheduler-ack mode, the scheduler keeps track of the Tx status of + * each frame within the BA window, including whether it's been transmitted, + * and whether it's been acknowledged by the receiving station. The device + * automatically processes block-acks received from the receiving STA, + * and reschedules un-acked frames to be retransmitted (successful + * Tx completion may end up being out-of-order). + * + * The driver must maintain the queue's Byte Count table in host DRAM + * (struct iwl4965_sched_queue_byte_cnt_tbl) for this mode. + * This mode does not support fragmentation. + * + * 2) FIFO (a.k.a. non-Scheduler-ACK), in which each TFD is processed in order. + * The device may automatically retry Tx, but will retry only one frame + * at a time, until receiving ACK from receiving station, or reaching + * retry limit and giving up. + * + * The command queue (#4) must use this mode! + * This mode does not require use of the Byte Count table in host DRAM. + * + * Driver controls scheduler operation via 3 means: + * 1) Scheduler registers + * 2) Shared scheduler data base in internal 4956 SRAM + * 3) Shared data in host DRAM + * + * Initialization: + * + * When loading, driver should allocate memory for: + * 1) 16 TFD circular buffers, each with space for (typically) 256 TFDs. + * 2) 16 Byte Count circular buffers in 16 KBytes contiguous memory + * (1024 bytes for each queue). + * + * After receiving "Alive" response from uCode, driver must initialize + * the scheduler (especially for queue #4, the command queue, otherwise + * the driver can't issue commands!): + */ + +/** + * Max Tx window size is the max number of contiguous TFDs that the scheduler + * can keep track of at one time when creating block-ack chains of frames. + * Note that "64" matches the number of ack bits in a block-ack packet. + * Driver should use SCD_WIN_SIZE and SCD_FRAME_LIMIT values to initialize + * SCD_CONTEXT_QUEUE_OFFSET(x) values. + */ #define SCD_WIN_SIZE 64 #define SCD_FRAME_LIMIT 64 -/* SRAM structures */ -#define SCD_CONTEXT_DATA_OFFSET 0x380 -#define SCD_TX_STTS_BITMAP_OFFSET 0x400 -#define SCD_TRANSLATE_TBL_OFFSET 0x500 -#define SCD_CONTEXT_QUEUE_OFFSET(x) (SCD_CONTEXT_DATA_OFFSET + ((x) * 8)) -#define SCD_TRANSLATE_TBL_OFFSET_QUEUE(x) \ - ((SCD_TRANSLATE_TBL_OFFSET + ((x) * 2)) & 0xfffffffc) +/* SCD registers are internal, must be accessed via HBUS_TARG_PRPH regs */ +#define SCD_START_OFFSET 0xa02c00 + +/* + * 4965 tells driver SRAM address for internal scheduler structs via this reg. + * Value is valid only after "Alive" response from uCode. + */ +#define SCD_SRAM_BASE_ADDR (SCD_START_OFFSET + 0x0) +/* + * Driver may need to update queue-empty bits after changing queue's + * write and read pointers (indexes) during (re-)initialization (i.e. when + * scheduler is not tracking what's happening). + * Bit fields: + * 31-16: Write mask -- 1: update empty bit, 0: don't change empty bit + * 15-00: Empty state, one for each queue -- 1: empty, 0: non-empty + * NOTE: This register is not used by Linux driver. + */ +#define SCD_EMPTY_BITS (SCD_START_OFFSET + 0x4) + +/* + * Physical base address of array of byte count (BC) circular buffers (CBs). + * Each Tx queue has a BC CB in host DRAM to support Scheduler-ACK mode. + * This register points to BC CB for queue 0, must be on 1024-byte boundary. + * Others are spaced by 1024 bytes. + * Each BC CB is 2 bytes * (256 + 64) = 740 bytes, followed by 384 bytes pad. + * (Index into a queue's BC CB) = (index into queue's TFD CB) = (SSN & 0xff). + * Bit fields: + * 25-00: Byte Count CB physical address [35:10], must be 1024-byte aligned. + */ +#define SCD_DRAM_BASE_ADDR (SCD_START_OFFSET + 0x10) + +/* + * Enables any/all Tx DMA/FIFO channels. + * Scheduler generates requests for only the active channels. + * Set this to 0xff to enable all 8 channels (normal usage). + * Bit fields: + * 7- 0: Enable (1), disable (0), one bit for each channel 0-7 + */ +#define SCD_TXFACT (SCD_START_OFFSET + 0x1c) + +/* Mask to enable contiguous Tx DMA/FIFO channels between "lo" and "hi". */ #define SCD_TXFACT_REG_TXFIFO_MASK(lo, hi) \ ((1<<(hi))|((1<<(hi))-(1<<(lo)))) +/* + * Queue (x) Write Pointers (indexes, really!), one for each Tx queue. + * Initialized and updated by driver as new TFDs are added to queue. + * NOTE: If using Block Ack, index must correspond to frame's + * Start Sequence Number; index = (SSN & 0xff) + * NOTE: Alternative to HBUS_TARG_WRPTR, which is what Linux driver uses? + */ +#define SCD_QUEUE_WRPTR(x) (SCD_START_OFFSET + 0x24 + (x) * 4) + +/* + * Queue (x) Read Pointers (indexes, really!), one for each Tx queue. + * For FIFO mode, index indicates next frame to transmit. + * For Scheduler-ACK mode, index indicates first frame in Tx window. + * Initialized by driver, updated by scheduler. + */ +#define SCD_QUEUE_RDPTR(x) (SCD_START_OFFSET + 0x64 + (x) * 4) + +/* + * Select which queues work in chain mode (1) vs. not (0). + * Use chain mode to build chains of aggregated frames. + * Bit fields: + * 31-16: Reserved + * 15-00: Mode, one bit for each queue -- 1: Chain mode, 0: one-at-a-time + * NOTE: If driver sets up queue for chain mode, it should be also set up + * Scheduler-ACK mode as well, via SCD_QUEUE_STATUS_BITS(x). + */ +#define SCD_QUEUECHAIN_SEL (SCD_START_OFFSET + 0xd0) + +/* + * Select which queues interrupt driver when scheduler increments + * a queue's read pointer (index). + * Bit fields: + * 31-16: Reserved + * 15-00: Interrupt enable, one bit for each queue -- 1: enabled, 0: disabled + * NOTE: This functionality is apparently a no-op; driver relies on interrupts + * from Rx queue to read Tx command responses and update Tx queues. + */ +#define SCD_INTERRUPT_MASK (SCD_START_OFFSET + 0xe4) + +/* + * Queue search status registers. One for each queue. + * Sets up queue mode and assigns queue to Tx DMA channel. + * Bit fields: + * 19-10: Write mask/enable bits for bits 0-9 + * 9: Driver should init to "0" + * 8: Scheduler-ACK mode (1), non-Scheduler-ACK (i.e. FIFO) mode (0). + * Driver should init to "1" for aggregation mode, or "0" otherwise. + * 7-6: Driver should init to "0" + * 5: Window Size Left; indicates whether scheduler can request + * another TFD, based on window size, etc. Driver should init + * this bit to "1" for aggregation mode, or "0" for non-agg. + * 4-1: Tx FIFO to use (range 0-7). + * 0: Queue is active (1), not active (0). + * Other bits should be written as "0" + * + * NOTE: If enabling Scheduler-ACK mode, chain mode should also be enabled + * via SCD_QUEUECHAIN_SEL. + */ +#define SCD_QUEUE_STATUS_BITS(x) (SCD_START_OFFSET + 0x104 + (x) * 4) + +/* Bit field positions */ #define SCD_QUEUE_STTS_REG_POS_ACTIVE (0) #define SCD_QUEUE_STTS_REG_POS_TXF (1) #define SCD_QUEUE_STTS_REG_POS_WSL (5) #define SCD_QUEUE_STTS_REG_POS_SCD_ACK (8) + +/* Write masks */ #define SCD_QUEUE_STTS_REG_POS_SCD_ACT_EN (10) #define SCD_QUEUE_STTS_REG_MSK (0x0007FC00) +/** + * 4965 internal SRAM structures for scheduler, shared with driver ... + * + * Driver should clear and initialize the following areas after receiving + * "Alive" response from 4965 uCode, i.e. after initial + * uCode load, or after a uCode load done for error recovery: + * + * SCD_CONTEXT_DATA_OFFSET (size 128 bytes) + * SCD_TX_STTS_BITMAP_OFFSET (size 256 bytes) + * SCD_TRANSLATE_TBL_OFFSET (size 32 bytes) + * + * Driver accesses SRAM via HBUS_TARG_MEM_* registers. + * Driver reads base address of this scheduler area from SCD_SRAM_BASE_ADDR. + * All OFFSET values must be added to this base address. + */ + +/* + * Queue context. One 8-byte entry for each of 16 queues. + * + * Driver should clear this entire area (size 0x80) to 0 after receiving + * "Alive" notification from uCode. Additionally, driver should init + * each queue's entry as follows: + * + * LS Dword bit fields: + * 0-06: Max Tx window size for Scheduler-ACK. Driver should init to 64. + * + * MS Dword bit fields: + * 16-22: Frame limit. Driver should init to 10 (0xa). + * + * Driver should init all other bits to 0. + * + * Init must be done after driver receives "Alive" response from 4965 uCode, + * and when setting up queue for aggregation. + */ +#define SCD_CONTEXT_DATA_OFFSET 0x380 +#define SCD_CONTEXT_QUEUE_OFFSET(x) (SCD_CONTEXT_DATA_OFFSET + ((x) * 8)) + #define SCD_QUEUE_CTX_REG1_WIN_SIZE_POS (0) #define SCD_QUEUE_CTX_REG1_WIN_SIZE_MSK (0x0000007F) - #define SCD_QUEUE_CTX_REG2_FRAME_LIMIT_POS (16) #define SCD_QUEUE_CTX_REG2_FRAME_LIMIT_MSK (0x007F0000) +/* + * Tx Status Bitmap + * + * Driver should clear this entire area (size 0x100) to 0 after receiving + * "Alive" notification from uCode. Area is used only by device itself; + * no other support (besides clearing) is required from driver. + */ +#define SCD_TX_STTS_BITMAP_OFFSET 0x400 + +/* + * RAxTID to queue translation mapping. + * + * When queue is in Scheduler-ACK mode, frames placed in a that queue must be + * for only one combination of receiver address (RA) and traffic ID (TID), i.e. + * one QOS priority level destined for one station (for this wireless link, + * not final destination). The SCD_TRANSLATE_TABLE area provides 16 16-bit + * mappings, one for each of the 16 queues. If queue is not in Scheduler-ACK + * mode, the device ignores the mapping value. + * + * Bit fields, for each 16-bit map: + * 15-9: Reserved, set to 0 + * 8-4: Index into device's station table for recipient station + * 3-0: Traffic ID (tid), range 0-15 + * + * Driver should clear this entire area (size 32 bytes) to 0 after receiving + * "Alive" notification from uCode. To update a 16-bit map value, driver + * must read a dword-aligned value from device SRAM, replace the 16-bit map + * value of interest, and write the dword value back into device SRAM. + */ +#define SCD_TRANSLATE_TBL_OFFSET 0x500 + +/* Find translation table dword to read/write for given queue */ +#define SCD_TRANSLATE_TBL_OFFSET_QUEUE(x) \ + ((SCD_TRANSLATE_TBL_OFFSET + ((x) * 2)) & 0xfffffffc) + +#define SCD_TXFIFO_POS_TID (0) +#define SCD_TXFIFO_POS_RA (4) +#define SCD_QUEUE_RA_TID_MAP_RATID_MSK (0x01FF) + +/*********************** END TX SCHEDULER *************************************/ + static inline u8 iwl4965_hw_get_rate(__le32 rate_n_flags) { return le32_to_cpu(rate_n_flags) & 0xFF; diff --git a/drivers/net/wireless/iwlwifi/iwl-prph.h b/drivers/net/wireless/iwlwifi/iwl-prph.h index 137947dd269f..4ba121634877 100644 --- a/drivers/net/wireless/iwlwifi/iwl-prph.h +++ b/drivers/net/wireless/iwlwifi/iwl-prph.h @@ -63,7 +63,10 @@ #ifndef __iwl_prph_h__ #define __iwl_prph_h__ - +/* + * Registers in this file are internal, not PCI bus memory mapped. + * Driver accesses these via HBUS_TARG_PRPH_* registers. + */ #define PRPH_BASE (0x00000) #define PRPH_END (0xFFFFF) @@ -225,8 +228,8 @@ #define BSM_SRAM_LOWER_BOUND (PRPH_BASE + 0x3800) #define BSM_SRAM_SIZE (1024) /* bytes */ -/* ALM SCD */ -/* SCD (Scheduler) */ + +/* 3945 Tx scheduler registers */ #define ALM_SCD_BASE (PRPH_BASE + 0x2E00) #define ALM_SCD_MODE_REG (ALM_SCD_BASE + 0x000) #define ALM_SCD_ARASTAT_REG (ALM_SCD_BASE + 0x004) @@ -236,7 +239,10 @@ #define ALM_SCD_SBYP_MODE_1_REG (ALM_SCD_BASE + 0x02C) #define ALM_SCD_SBYP_MODE_2_REG (ALM_SCD_BASE + 0x030) -/* 4965 SCD memory mapped registers */ +/* + * 4965 Tx Scheduler registers. + * Details are documented in iwl-4965-hw.h + */ #define KDR_SCD_BASE (PRPH_BASE + 0xa02c00) #define KDR_SCD_SRAM_BASE_ADDR (KDR_SCD_BASE + 0x0) diff --git a/drivers/net/wireless/iwlwifi/iwl4965-base.c b/drivers/net/wireless/iwlwifi/iwl4965-base.c index 43ce645e4a60..e15986c33d0b 100644 --- a/drivers/net/wireless/iwlwifi/iwl4965-base.c +++ b/drivers/net/wireless/iwlwifi/iwl4965-base.c @@ -201,6 +201,8 @@ static void iwl4965_print_hex_dump(int level, void *p, u32 len) * The 4965 operates with up to 17 queues: One receive queue, one transmit * queue (#4) for sending commands to the device firmware, and 15 other * Tx queues that may be mapped to prioritized Tx DMA/FIFO channels. + * + * See more detailed info in iwl-4965-hw.h. ***************************************************/ static int iwl4965_queue_space(const struct iwl4965_queue *q) |