diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/pcie/rx.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/pcie/rx.c | 1053 |
1 files changed, 1053 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c new file mode 100644 index 000000000000..d1a61ba6247a --- /dev/null +++ b/drivers/net/wireless/iwlwifi/pcie/rx.c @@ -0,0 +1,1053 @@ +/****************************************************************************** + * + * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved. + * + * Portions of this file are derived from the ipw3945 project, as well + * as portions of the ieee80211 subsystem header files. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA + * + * The full GNU General Public License is included in this distribution in the + * file called LICENSE. + * + * Contact Information: + * Intel Linux Wireless <ilw@linux.intel.com> + * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 + * + *****************************************************************************/ +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/gfp.h> + +#include "iwl-prph.h" +#include "iwl-io.h" +#include "internal.h" +#include "iwl-op-mode.h" + +#ifdef CONFIG_IWLWIFI_IDI +#include "iwl-amfh.h" +#endif + +/****************************************************************************** + * + * RX path functions + * + ******************************************************************************/ + +/* + * Rx theory of operation + * + * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs), + * each of which point to Receive Buffers to be filled by the NIC. These get + * used not only for Rx frames, but for any command response or notification + * from the NIC. The driver and NIC manage the Rx buffers by means + * of indexes into the circular buffer. + * + * Rx Queue Indexes + * The host/firmware share two index registers for managing the Rx buffers. + * + * The READ index maps to the first position that the firmware may be writing + * to -- the driver can read up to (but not including) this position and get + * good data. + * The READ index is managed by the firmware once the card is enabled. + * + * The WRITE index maps to the last position the driver has read from -- the + * position preceding WRITE is the last slot the firmware can place a packet. + * + * The queue is empty (no good data) if WRITE = READ - 1, and is full if + * WRITE = READ. + * + * During initialization, the host sets up the READ queue position to the first + * INDEX position, and WRITE to the last (READ - 1 wrapped) + * + * When the firmware places a packet in a buffer, it will advance the READ index + * and fire the RX interrupt. The driver can then query the READ index and + * process as many packets as possible, moving the WRITE index forward as it + * resets the Rx queue buffers with new memory. + * + * The management in the driver is as follows: + * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free. When + * iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled + * to replenish the iwl->rxq->rx_free. + * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the + * iwl->rxq is replenished and the READ INDEX is updated (updating the + * 'processed' and 'read' driver indexes as well) + * + A received packet is processed and handed to the kernel network stack, + * detached from the iwl->rxq. The driver 'processed' index is updated. + * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free + * list. If there are no allocated buffers in iwl->rxq->rx_free, the READ + * INDEX is not incremented and iwl->status(RX_STALLED) is set. If there + * were enough free buffers and RX_STALLED is set it is cleared. + * + * + * Driver sequence: + * + * iwl_rx_queue_alloc() Allocates rx_free + * iwl_rx_replenish() Replenishes rx_free list from rx_used, and calls + * iwl_rx_queue_restock + * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx + * queue, updates firmware pointers, and updates + * the WRITE index. If insufficient rx_free buffers + * are available, schedules iwl_rx_replenish + * + * -- enable interrupts -- + * ISR - iwl_rx() Detach iwl_rx_mem_buffers from pool up to the + * READ INDEX, detaching the SKB from the pool. + * Moves the packet buffer from queue to rx_used. + * Calls iwl_rx_queue_restock to refill any empty + * slots. + * ... + * + */ + +/** + * iwl_rx_queue_space - Return number of free slots available in queue. + */ +static int iwl_rx_queue_space(const struct iwl_rx_queue *q) +{ + int s = q->read - q->write; + if (s <= 0) + s += RX_QUEUE_SIZE; + /* keep some buffer to not confuse full and empty queue */ + s -= 2; + if (s < 0) + s = 0; + return s; +} + +/** + * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue + */ +void iwl_rx_queue_update_write_ptr(struct iwl_trans *trans, + struct iwl_rx_queue *q) +{ + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&q->lock, flags); + + if (q->need_update == 0) + goto exit_unlock; + + if (trans->cfg->base_params->shadow_reg_enable) { + /* shadow register enabled */ + /* Device expects a multiple of 8 */ + q->write_actual = (q->write & ~0x7); + iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, q->write_actual); + } else { + struct iwl_trans_pcie *trans_pcie = + IWL_TRANS_GET_PCIE_TRANS(trans); + + /* If power-saving is in use, make sure device is awake */ + if (test_bit(STATUS_TPOWER_PMI, &trans_pcie->status)) { + reg = iwl_read32(trans, CSR_UCODE_DRV_GP1); + + if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) { + IWL_DEBUG_INFO(trans, + "Rx queue requesting wakeup," + " GP1 = 0x%x\n", reg); + iwl_set_bit(trans, CSR_GP_CNTRL, + CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ); + goto exit_unlock; + } + + q->write_actual = (q->write & ~0x7); + iwl_write_direct32(trans, FH_RSCSR_CHNL0_WPTR, + q->write_actual); + + /* Else device is assumed to be awake */ + } else { + /* Device expects a multiple of 8 */ + q->write_actual = (q->write & ~0x7); + iwl_write_direct32(trans, FH_RSCSR_CHNL0_WPTR, + q->write_actual); + } + } + q->need_update = 0; + + exit_unlock: + spin_unlock_irqrestore(&q->lock, flags); +} + +/** + * iwlagn_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr + */ +static inline __le32 iwlagn_dma_addr2rbd_ptr(dma_addr_t dma_addr) +{ + return cpu_to_le32((u32)(dma_addr >> 8)); +} + +/** + * iwlagn_rx_queue_restock - refill RX queue from pre-allocated pool + * + * If there are slots in the RX queue that need to be restocked, + * and we have free pre-allocated buffers, fill the ranks as much + * as we can, pulling from rx_free. + * + * This moves the 'write' index forward to catch up with 'processed', and + * also updates the memory address in the firmware to reference the new + * target buffer. + */ +static void iwlagn_rx_queue_restock(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rx_queue *rxq = &trans_pcie->rxq; + struct list_head *element; + struct iwl_rx_mem_buffer *rxb; + unsigned long flags; + + spin_lock_irqsave(&rxq->lock, flags); + while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) { + /* The overwritten rxb must be a used one */ + rxb = rxq->queue[rxq->write]; + BUG_ON(rxb && rxb->page); + + /* Get next free Rx buffer, remove from free list */ + element = rxq->rx_free.next; + rxb = list_entry(element, struct iwl_rx_mem_buffer, list); + list_del(element); + + /* Point to Rx buffer via next RBD in circular buffer */ + rxq->bd[rxq->write] = iwlagn_dma_addr2rbd_ptr(rxb->page_dma); + rxq->queue[rxq->write] = rxb; + rxq->write = (rxq->write + 1) & RX_QUEUE_MASK; + rxq->free_count--; + } + spin_unlock_irqrestore(&rxq->lock, flags); + /* If the pre-allocated buffer pool is dropping low, schedule to + * refill it */ + if (rxq->free_count <= RX_LOW_WATERMARK) + schedule_work(&trans_pcie->rx_replenish); + + + /* If we've added more space for the firmware to place data, tell it. + * Increment device's write pointer in multiples of 8. */ + if (rxq->write_actual != (rxq->write & ~0x7)) { + spin_lock_irqsave(&rxq->lock, flags); + rxq->need_update = 1; + spin_unlock_irqrestore(&rxq->lock, flags); + iwl_rx_queue_update_write_ptr(trans, rxq); + } +} + +/** + * iwlagn_rx_replenish - Move all used packet from rx_used to rx_free + * + * When moving to rx_free an SKB is allocated for the slot. + * + * Also restock the Rx queue via iwl_rx_queue_restock. + * This is called as a scheduled work item (except for during initialization) + */ +static void iwlagn_rx_allocate(struct iwl_trans *trans, gfp_t priority) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rx_queue *rxq = &trans_pcie->rxq; + struct list_head *element; + struct iwl_rx_mem_buffer *rxb; + struct page *page; + unsigned long flags; + gfp_t gfp_mask = priority; + + while (1) { + spin_lock_irqsave(&rxq->lock, flags); + if (list_empty(&rxq->rx_used)) { + spin_unlock_irqrestore(&rxq->lock, flags); + return; + } + spin_unlock_irqrestore(&rxq->lock, flags); + + if (rxq->free_count > RX_LOW_WATERMARK) + gfp_mask |= __GFP_NOWARN; + + if (trans_pcie->rx_page_order > 0) + gfp_mask |= __GFP_COMP; + + /* Alloc a new receive buffer */ + page = alloc_pages(gfp_mask, trans_pcie->rx_page_order); + if (!page) { + if (net_ratelimit()) + IWL_DEBUG_INFO(trans, "alloc_pages failed, " + "order: %d\n", + trans_pcie->rx_page_order); + + if ((rxq->free_count <= RX_LOW_WATERMARK) && + net_ratelimit()) + IWL_CRIT(trans, "Failed to alloc_pages with %s." + "Only %u free buffers remaining.\n", + priority == GFP_ATOMIC ? + "GFP_ATOMIC" : "GFP_KERNEL", + rxq->free_count); + /* We don't reschedule replenish work here -- we will + * call the restock method and if it still needs + * more buffers it will schedule replenish */ + return; + } + + spin_lock_irqsave(&rxq->lock, flags); + + if (list_empty(&rxq->rx_used)) { + spin_unlock_irqrestore(&rxq->lock, flags); + __free_pages(page, trans_pcie->rx_page_order); + return; + } + element = rxq->rx_used.next; + rxb = list_entry(element, struct iwl_rx_mem_buffer, list); + list_del(element); + + spin_unlock_irqrestore(&rxq->lock, flags); + + BUG_ON(rxb->page); + rxb->page = page; + /* Get physical address of the RB */ + rxb->page_dma = + dma_map_page(trans->dev, page, 0, + PAGE_SIZE << trans_pcie->rx_page_order, + DMA_FROM_DEVICE); + /* dma address must be no more than 36 bits */ + BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36)); + /* and also 256 byte aligned! */ + BUG_ON(rxb->page_dma & DMA_BIT_MASK(8)); + + spin_lock_irqsave(&rxq->lock, flags); + + list_add_tail(&rxb->list, &rxq->rx_free); + rxq->free_count++; + + spin_unlock_irqrestore(&rxq->lock, flags); + } +} + +void iwlagn_rx_replenish(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + unsigned long flags; + + iwlagn_rx_allocate(trans, GFP_KERNEL); + + spin_lock_irqsave(&trans_pcie->irq_lock, flags); + iwlagn_rx_queue_restock(trans); + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); +} + +static void iwlagn_rx_replenish_now(struct iwl_trans *trans) +{ + iwlagn_rx_allocate(trans, GFP_ATOMIC); + + iwlagn_rx_queue_restock(trans); +} + +void iwl_bg_rx_replenish(struct work_struct *data) +{ + struct iwl_trans_pcie *trans_pcie = + container_of(data, struct iwl_trans_pcie, rx_replenish); + + iwlagn_rx_replenish(trans_pcie->trans); +} + +static void iwl_rx_handle_rxbuf(struct iwl_trans *trans, + struct iwl_rx_mem_buffer *rxb) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rx_queue *rxq = &trans_pcie->rxq; + struct iwl_tx_queue *txq = &trans_pcie->txq[trans_pcie->cmd_queue]; + unsigned long flags; + bool page_stolen = false; + int max_len = PAGE_SIZE << trans_pcie->rx_page_order; + u32 offset = 0; + + if (WARN_ON(!rxb)) + return; + + dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE); + + while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) { + struct iwl_rx_packet *pkt; + struct iwl_device_cmd *cmd; + u16 sequence; + bool reclaim; + int index, cmd_index, err, len; + struct iwl_rx_cmd_buffer rxcb = { + ._offset = offset, + ._page = rxb->page, + ._page_stolen = false, + .truesize = max_len, + }; + + pkt = rxb_addr(&rxcb); + + if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID)) + break; + + IWL_DEBUG_RX(trans, "cmd at offset %d: %s (0x%.2x)\n", + rxcb._offset, + trans_pcie_get_cmd_string(trans_pcie, pkt->hdr.cmd), + pkt->hdr.cmd); + + len = le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK; + len += sizeof(u32); /* account for status word */ + trace_iwlwifi_dev_rx(trans->dev, pkt, len); + + /* Reclaim a command buffer only if this packet is a response + * to a (driver-originated) command. + * If the packet (e.g. Rx frame) originated from uCode, + * there is no command buffer to reclaim. + * Ucode should set SEQ_RX_FRAME bit if ucode-originated, + * but apparently a few don't get set; catch them here. */ + reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME); + if (reclaim) { + int i; + + for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) { + if (trans_pcie->no_reclaim_cmds[i] == + pkt->hdr.cmd) { + reclaim = false; + break; + } + } + } + + sequence = le16_to_cpu(pkt->hdr.sequence); + index = SEQ_TO_INDEX(sequence); + cmd_index = get_cmd_index(&txq->q, index); + + if (reclaim) + cmd = txq->entries[cmd_index].cmd; + else + cmd = NULL; + + err = iwl_op_mode_rx(trans->op_mode, &rxcb, cmd); + + /* + * After here, we should always check rxcb._page_stolen, + * if it is true then one of the handlers took the page. + */ + + if (reclaim) { + /* Invoke any callbacks, transfer the buffer to caller, + * and fire off the (possibly) blocking + * iwl_trans_send_cmd() + * as we reclaim the driver command queue */ + if (!rxcb._page_stolen) + iwl_tx_cmd_complete(trans, &rxcb, err); + else + IWL_WARN(trans, "Claim null rxb?\n"); + } + + page_stolen |= rxcb._page_stolen; + offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN); + } + + /* page was stolen from us -- free our reference */ + if (page_stolen) { + __free_pages(rxb->page, trans_pcie->rx_page_order); + rxb->page = NULL; + } + + /* Reuse the page if possible. For notification packets and + * SKBs that fail to Rx correctly, add them back into the + * rx_free list for reuse later. */ + spin_lock_irqsave(&rxq->lock, flags); + if (rxb->page != NULL) { + rxb->page_dma = + dma_map_page(trans->dev, rxb->page, 0, + PAGE_SIZE << trans_pcie->rx_page_order, + DMA_FROM_DEVICE); + list_add_tail(&rxb->list, &rxq->rx_free); + rxq->free_count++; + } else + list_add_tail(&rxb->list, &rxq->rx_used); + spin_unlock_irqrestore(&rxq->lock, flags); +} + +/** + * iwl_rx_handle - Main entry function for receiving responses from uCode + * + * Uses the priv->rx_handlers callback function array to invoke + * the appropriate handlers, including command responses, + * frame-received notifications, and other notifications. + */ +static void iwl_rx_handle(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rx_queue *rxq = &trans_pcie->rxq; + u32 r, i; + u8 fill_rx = 0; + u32 count = 8; + int total_empty; + + /* uCode's read index (stored in shared DRAM) indicates the last Rx + * buffer that the driver may process (last buffer filled by ucode). */ + r = le16_to_cpu(rxq->rb_stts->closed_rb_num) & 0x0FFF; + i = rxq->read; + + /* Rx interrupt, but nothing sent from uCode */ + if (i == r) + IWL_DEBUG_RX(trans, "HW = SW = %d\n", r); + + /* calculate total frames need to be restock after handling RX */ + total_empty = r - rxq->write_actual; + if (total_empty < 0) + total_empty += RX_QUEUE_SIZE; + + if (total_empty > (RX_QUEUE_SIZE / 2)) + fill_rx = 1; + + while (i != r) { + struct iwl_rx_mem_buffer *rxb; + + rxb = rxq->queue[i]; + rxq->queue[i] = NULL; + + IWL_DEBUG_RX(trans, "rxbuf: HW = %d, SW = %d (%p)\n", + r, i, rxb); + iwl_rx_handle_rxbuf(trans, rxb); + + i = (i + 1) & RX_QUEUE_MASK; + /* If there are a lot of unused frames, + * restock the Rx queue so ucode wont assert. */ + if (fill_rx) { + count++; + if (count >= 8) { + rxq->read = i; + iwlagn_rx_replenish_now(trans); + count = 0; + } + } + } + + /* Backtrack one entry */ + rxq->read = i; + if (fill_rx) + iwlagn_rx_replenish_now(trans); + else + iwlagn_rx_queue_restock(trans); +} + +/** + * iwl_irq_handle_error - called for HW or SW error interrupt from card + */ +static void iwl_irq_handle_error(struct iwl_trans *trans) +{ + /* W/A for WiFi/WiMAX coex and WiMAX own the RF */ + if (trans->cfg->internal_wimax_coex && + (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) & + APMS_CLK_VAL_MRB_FUNC_MODE) || + (iwl_read_prph(trans, APMG_PS_CTRL_REG) & + APMG_PS_CTRL_VAL_RESET_REQ))) { + struct iwl_trans_pcie *trans_pcie = + IWL_TRANS_GET_PCIE_TRANS(trans); + + clear_bit(STATUS_HCMD_ACTIVE, &trans_pcie->status); + iwl_op_mode_wimax_active(trans->op_mode); + wake_up(&trans->wait_command_queue); + return; + } + + iwl_dump_csr(trans); + iwl_dump_fh(trans, NULL); + + iwl_op_mode_nic_error(trans->op_mode); +} + +/* tasklet for iwlagn interrupt */ +void iwl_irq_tasklet(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct isr_statistics *isr_stats = &trans_pcie->isr_stats; + u32 inta = 0; + u32 handled = 0; + unsigned long flags; + u32 i; +#ifdef CONFIG_IWLWIFI_DEBUG + u32 inta_mask; +#endif + + spin_lock_irqsave(&trans_pcie->irq_lock, flags); + + /* Ack/clear/reset pending uCode interrupts. + * Note: Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS, + */ + /* There is a hardware bug in the interrupt mask function that some + * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if + * they are disabled in the CSR_INT_MASK register. Furthermore the + * ICT interrupt handling mechanism has another bug that might cause + * these unmasked interrupts fail to be detected. We workaround the + * hardware bugs here by ACKing all the possible interrupts so that + * interrupt coalescing can still be achieved. + */ + iwl_write32(trans, CSR_INT, + trans_pcie->inta | ~trans_pcie->inta_mask); + + inta = trans_pcie->inta; + +#ifdef CONFIG_IWLWIFI_DEBUG + if (iwl_have_debug_level(IWL_DL_ISR)) { + /* just for debug */ + inta_mask = iwl_read32(trans, CSR_INT_MASK); + IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n", + inta, inta_mask); + } +#endif + + /* saved interrupt in inta variable now we can reset trans_pcie->inta */ + trans_pcie->inta = 0; + + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); + + /* Now service all interrupt bits discovered above. */ + if (inta & CSR_INT_BIT_HW_ERR) { + IWL_ERR(trans, "Hardware error detected. Restarting.\n"); + + /* Tell the device to stop sending interrupts */ + iwl_disable_interrupts(trans); + + isr_stats->hw++; + iwl_irq_handle_error(trans); + + handled |= CSR_INT_BIT_HW_ERR; + + return; + } + +#ifdef CONFIG_IWLWIFI_DEBUG + if (iwl_have_debug_level(IWL_DL_ISR)) { + /* NIC fires this, but we don't use it, redundant with WAKEUP */ + if (inta & CSR_INT_BIT_SCD) { + IWL_DEBUG_ISR(trans, "Scheduler finished to transmit " + "the frame/frames.\n"); + isr_stats->sch++; + } + + /* Alive notification via Rx interrupt will do the real work */ + if (inta & CSR_INT_BIT_ALIVE) { + IWL_DEBUG_ISR(trans, "Alive interrupt\n"); + isr_stats->alive++; + } + } +#endif + /* Safely ignore these bits for debug checks below */ + inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE); + + /* HW RF KILL switch toggled */ + if (inta & CSR_INT_BIT_RF_KILL) { + bool hw_rfkill; + + hw_rfkill = iwl_is_rfkill_set(trans); + IWL_WARN(trans, "RF_KILL bit toggled to %s.\n", + hw_rfkill ? "disable radio" : "enable radio"); + + isr_stats->rfkill++; + + iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill); + + handled |= CSR_INT_BIT_RF_KILL; + } + + /* Chip got too hot and stopped itself */ + if (inta & CSR_INT_BIT_CT_KILL) { + IWL_ERR(trans, "Microcode CT kill error detected.\n"); + isr_stats->ctkill++; + handled |= CSR_INT_BIT_CT_KILL; + } + + /* Error detected by uCode */ + if (inta & CSR_INT_BIT_SW_ERR) { + IWL_ERR(trans, "Microcode SW error detected. " + " Restarting 0x%X.\n", inta); + isr_stats->sw++; + iwl_irq_handle_error(trans); + handled |= CSR_INT_BIT_SW_ERR; + } + + /* uCode wakes up after power-down sleep */ + if (inta & CSR_INT_BIT_WAKEUP) { + IWL_DEBUG_ISR(trans, "Wakeup interrupt\n"); + iwl_rx_queue_update_write_ptr(trans, &trans_pcie->rxq); + for (i = 0; i < trans->cfg->base_params->num_of_queues; i++) + iwl_txq_update_write_ptr(trans, + &trans_pcie->txq[i]); + + isr_stats->wakeup++; + + handled |= CSR_INT_BIT_WAKEUP; + } + + /* All uCode command responses, including Tx command responses, + * Rx "responses" (frame-received notification), and other + * notifications from uCode come through here*/ + if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX | + CSR_INT_BIT_RX_PERIODIC)) { + IWL_DEBUG_ISR(trans, "Rx interrupt\n"); + if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) { + handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX); + iwl_write32(trans, CSR_FH_INT_STATUS, + CSR_FH_INT_RX_MASK); + } + if (inta & CSR_INT_BIT_RX_PERIODIC) { + handled |= CSR_INT_BIT_RX_PERIODIC; + iwl_write32(trans, + CSR_INT, CSR_INT_BIT_RX_PERIODIC); + } + /* Sending RX interrupt require many steps to be done in the + * the device: + * 1- write interrupt to current index in ICT table. + * 2- dma RX frame. + * 3- update RX shared data to indicate last write index. + * 4- send interrupt. + * This could lead to RX race, driver could receive RX interrupt + * but the shared data changes does not reflect this; + * periodic interrupt will detect any dangling Rx activity. + */ + + /* Disable periodic interrupt; we use it as just a one-shot. */ + iwl_write8(trans, CSR_INT_PERIODIC_REG, + CSR_INT_PERIODIC_DIS); +#ifdef CONFIG_IWLWIFI_IDI + iwl_amfh_rx_handler(); +#else + iwl_rx_handle(trans); +#endif + /* + * Enable periodic interrupt in 8 msec only if we received + * real RX interrupt (instead of just periodic int), to catch + * any dangling Rx interrupt. If it was just the periodic + * interrupt, there was no dangling Rx activity, and no need + * to extend the periodic interrupt; one-shot is enough. + */ + if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) + iwl_write8(trans, CSR_INT_PERIODIC_REG, + CSR_INT_PERIODIC_ENA); + + isr_stats->rx++; + } + + /* This "Tx" DMA channel is used only for loading uCode */ + if (inta & CSR_INT_BIT_FH_TX) { + iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK); + IWL_DEBUG_ISR(trans, "uCode load interrupt\n"); + isr_stats->tx++; + handled |= CSR_INT_BIT_FH_TX; + /* Wake up uCode load routine, now that load is complete */ + trans_pcie->ucode_write_complete = true; + wake_up(&trans_pcie->ucode_write_waitq); + } + + if (inta & ~handled) { + IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled); + isr_stats->unhandled++; + } + + if (inta & ~(trans_pcie->inta_mask)) { + IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n", + inta & ~trans_pcie->inta_mask); + } + + /* Re-enable all interrupts */ + /* only Re-enable if disabled by irq */ + if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status)) + iwl_enable_interrupts(trans); + /* Re-enable RF_KILL if it occurred */ + else if (handled & CSR_INT_BIT_RF_KILL) + iwl_enable_rfkill_int(trans); +} + +/****************************************************************************** + * + * ICT functions + * + ******************************************************************************/ + +/* a device (PCI-E) page is 4096 bytes long */ +#define ICT_SHIFT 12 +#define ICT_SIZE (1 << ICT_SHIFT) +#define ICT_COUNT (ICT_SIZE / sizeof(u32)) + +/* Free dram table */ +void iwl_free_isr_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + + if (trans_pcie->ict_tbl) { + dma_free_coherent(trans->dev, ICT_SIZE, + trans_pcie->ict_tbl, + trans_pcie->ict_tbl_dma); + trans_pcie->ict_tbl = NULL; + trans_pcie->ict_tbl_dma = 0; + } +} + + +/* + * allocate dram shared table, it is an aligned memory + * block of ICT_SIZE. + * also reset all data related to ICT table interrupt. + */ +int iwl_alloc_isr_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + + trans_pcie->ict_tbl = + dma_alloc_coherent(trans->dev, ICT_SIZE, + &trans_pcie->ict_tbl_dma, + GFP_KERNEL); + if (!trans_pcie->ict_tbl) + return -ENOMEM; + + /* just an API sanity check ... it is guaranteed to be aligned */ + if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) { + iwl_free_isr_ict(trans); + return -EINVAL; + } + + IWL_DEBUG_ISR(trans, "ict dma addr %Lx\n", + (unsigned long long)trans_pcie->ict_tbl_dma); + + IWL_DEBUG_ISR(trans, "ict vir addr %p\n", trans_pcie->ict_tbl); + + /* reset table and index to all 0 */ + memset(trans_pcie->ict_tbl, 0, ICT_SIZE); + trans_pcie->ict_index = 0; + + /* add periodic RX interrupt */ + trans_pcie->inta_mask |= CSR_INT_BIT_RX_PERIODIC; + return 0; +} + +/* Device is going up inform it about using ICT interrupt table, + * also we need to tell the driver to start using ICT interrupt. + */ +void iwl_reset_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + u32 val; + unsigned long flags; + + if (!trans_pcie->ict_tbl) + return; + + spin_lock_irqsave(&trans_pcie->irq_lock, flags); + iwl_disable_interrupts(trans); + + memset(trans_pcie->ict_tbl, 0, ICT_SIZE); + + val = trans_pcie->ict_tbl_dma >> ICT_SHIFT; + + val |= CSR_DRAM_INT_TBL_ENABLE; + val |= CSR_DRAM_INIT_TBL_WRAP_CHECK; + + IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val); + + iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val); + trans_pcie->use_ict = true; + trans_pcie->ict_index = 0; + iwl_write32(trans, CSR_INT, trans_pcie->inta_mask); + iwl_enable_interrupts(trans); + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); +} + +/* Device is going down disable ict interrupt usage */ +void iwl_disable_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + unsigned long flags; + + spin_lock_irqsave(&trans_pcie->irq_lock, flags); + trans_pcie->use_ict = false; + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); +} + +/* legacy (non-ICT) ISR. Assumes that trans_pcie->irq_lock is held */ +static irqreturn_t iwl_isr(int irq, void *data) +{ + struct iwl_trans *trans = data; + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + u32 inta, inta_mask; +#ifdef CONFIG_IWLWIFI_DEBUG + u32 inta_fh; +#endif + + lockdep_assert_held(&trans_pcie->irq_lock); + + trace_iwlwifi_dev_irq(trans->dev); + + /* Disable (but don't clear!) interrupts here to avoid + * back-to-back ISRs and sporadic interrupts from our NIC. + * If we have something to service, the tasklet will re-enable ints. + * If we *don't* have something, we'll re-enable before leaving here. */ + inta_mask = iwl_read32(trans, CSR_INT_MASK); /* just for debug */ + iwl_write32(trans, CSR_INT_MASK, 0x00000000); + + /* Discover which interrupts are active/pending */ + inta = iwl_read32(trans, CSR_INT); + + /* Ignore interrupt if there's nothing in NIC to service. + * This may be due to IRQ shared with another device, + * or due to sporadic interrupts thrown from our NIC. */ + if (!inta) { + IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n"); + goto none; + } + + if ((inta == 0xFFFFFFFF) || ((inta & 0xFFFFFFF0) == 0xa5a5a5a0)) { + /* Hardware disappeared. It might have already raised + * an interrupt */ + IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta); + return IRQ_HANDLED; + } + +#ifdef CONFIG_IWLWIFI_DEBUG + if (iwl_have_debug_level(IWL_DL_ISR)) { + inta_fh = iwl_read32(trans, CSR_FH_INT_STATUS); + IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x, " + "fh 0x%08x\n", inta, inta_mask, inta_fh); + } +#endif + + trans_pcie->inta |= inta; + /* iwl_irq_tasklet() will service interrupts and re-enable them */ + if (likely(inta)) + tasklet_schedule(&trans_pcie->irq_tasklet); + else if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) && + !trans_pcie->inta) + iwl_enable_interrupts(trans); + +none: + /* re-enable interrupts here since we don't have anything to service. */ + /* only Re-enable if disabled by irq and no schedules tasklet. */ + if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) && + !trans_pcie->inta) + iwl_enable_interrupts(trans); + + return IRQ_NONE; +} + +/* interrupt handler using ict table, with this interrupt driver will + * stop using INTA register to get device's interrupt, reading this register + * is expensive, device will write interrupts in ICT dram table, increment + * index then will fire interrupt to driver, driver will OR all ICT table + * entries from current index up to table entry with 0 value. the result is + * the interrupt we need to service, driver will set the entries back to 0 and + * set index. + */ +irqreturn_t iwl_isr_ict(int irq, void *data) +{ + struct iwl_trans *trans = data; + struct iwl_trans_pcie *trans_pcie; + u32 inta, inta_mask; + u32 val = 0; + u32 read; + unsigned long flags; + + if (!trans) + return IRQ_NONE; + + trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + + spin_lock_irqsave(&trans_pcie->irq_lock, flags); + + /* dram interrupt table not set yet, + * use legacy interrupt. + */ + if (unlikely(!trans_pcie->use_ict)) { + irqreturn_t ret = iwl_isr(irq, data); + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); + return ret; + } + + trace_iwlwifi_dev_irq(trans->dev); + + + /* Disable (but don't clear!) interrupts here to avoid + * back-to-back ISRs and sporadic interrupts from our NIC. + * If we have something to service, the tasklet will re-enable ints. + * If we *don't* have something, we'll re-enable before leaving here. + */ + inta_mask = iwl_read32(trans, CSR_INT_MASK); /* just for debug */ + iwl_write32(trans, CSR_INT_MASK, 0x00000000); + + + /* Ignore interrupt if there's nothing in NIC to service. + * This may be due to IRQ shared with another device, + * or due to sporadic interrupts thrown from our NIC. */ + read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]); + trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read); + if (!read) { + IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n"); + goto none; + } + + /* + * Collect all entries up to the first 0, starting from ict_index; + * note we already read at ict_index. + */ + do { + val |= read; + IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n", + trans_pcie->ict_index, read); + trans_pcie->ict_tbl[trans_pcie->ict_index] = 0; + trans_pcie->ict_index = + iwl_queue_inc_wrap(trans_pcie->ict_index, ICT_COUNT); + + read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]); + trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, + read); + } while (read); + + /* We should not get this value, just ignore it. */ + if (val == 0xffffffff) + val = 0; + + /* + * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit + * (bit 15 before shifting it to 31) to clear when using interrupt + * coalescing. fortunately, bits 18 and 19 stay set when this happens + * so we use them to decide on the real state of the Rx bit. + * In order words, bit 15 is set if bit 18 or bit 19 are set. + */ + if (val & 0xC0000) + val |= 0x8000; + + inta = (0xff & val) | ((0xff00 & val) << 16); + IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x ict 0x%08x\n", + inta, inta_mask, val); + + inta &= trans_pcie->inta_mask; + trans_pcie->inta |= inta; + + /* iwl_irq_tasklet() will service interrupts and re-enable them */ + if (likely(inta)) + tasklet_schedule(&trans_pcie->irq_tasklet); + else if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) && + !trans_pcie->inta) { + /* Allow interrupt if was disabled by this handler and + * no tasklet was schedules, We should not enable interrupt, + * tasklet will enable it. + */ + iwl_enable_interrupts(trans); + } + + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); + return IRQ_HANDLED; + + none: + /* re-enable interrupts here since we don't have anything to service. + * only Re-enable if disabled by irq. + */ + if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) && + !trans_pcie->inta) + iwl_enable_interrupts(trans); + + spin_unlock_irqrestore(&trans_pcie->irq_lock, flags); + return IRQ_NONE; +} |