diff options
Diffstat (limited to 'drivers/net/wireless/intel/iwlwifi/pcie/rx.c')
| -rw-r--r-- | drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 1556 |
1 files changed, 1556 insertions, 0 deletions
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c new file mode 100644 index 000000000000..ccafbd8cf4b3 --- /dev/null +++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c @@ -0,0 +1,1556 @@ +/****************************************************************************** + * + * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved. + * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH + * + * 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 <linuxwifi@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" + +/****************************************************************************** + * + * 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 RBDs is stored in iwl->rxq->rx_free. + * When the interrupt handler is called, the request is processed. + * The page is either stolen - transferred to the upper layer + * or reused - added immediately to the iwl->rxq->rx_free list. + * + When the page is stolen - the driver updates the matching queue's used + * count, detaches the RBD and transfers it to the queue used list. + * When there are two used RBDs - they are transferred to the allocator empty + * list. Work is then scheduled for the allocator to start allocating + * eight buffers. + * When there are another 6 used RBDs - they are transferred to the allocator + * empty list and the driver tries to claim the pre-allocated buffers and + * add them to iwl->rxq->rx_free. If it fails - it continues to claim them + * until ready. + * When there are 8+ buffers in the free list - either from allocation or from + * 8 reused unstolen pages - restock is called to update the FW and indexes. + * + In order to make sure the allocator always has RBDs to use for allocation + * the allocator has initial pool in the size of num_queues*(8-2) - the + * maximum missing RBDs per allocation request (request posted with 2 + * empty RBDs, there is no guarantee when the other 6 RBDs are supplied). + * The queues supplies the recycle of the rest of the RBDs. + * + A received packet is processed and handed to the kernel network stack, + * detached from the iwl->rxq. The driver 'processed' index is updated. + * + 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_rxq_alloc() Allocates rx_free + * iwl_pcie_rx_replenish() Replenishes rx_free list from rx_used, and calls + * iwl_pcie_rxq_restock. + * Used only during initialization. + * iwl_pcie_rxq_restock() Moves available buffers from rx_free into Rx + * queue, updates firmware pointers, and updates + * the WRITE index. + * iwl_pcie_rx_allocator() Background work for allocating pages. + * + * -- 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. + * Posts and claims requests to the allocator. + * Calls iwl_pcie_rxq_restock to refill any empty + * slots. + * + * RBD life-cycle: + * + * Init: + * rxq.pool -> rxq.rx_used -> rxq.rx_free -> rxq.queue + * + * Regular Receive interrupt: + * Page Stolen: + * rxq.queue -> rxq.rx_used -> allocator.rbd_empty -> + * allocator.rbd_allocated -> rxq.rx_free -> rxq.queue + * Page not Stolen: + * rxq.queue -> rxq.rx_free -> rxq.queue + * ... + * + */ + +/* + * iwl_rxq_space - Return number of free slots available in queue. + */ +static int iwl_rxq_space(const struct iwl_rxq *rxq) +{ + /* Make sure RX_QUEUE_SIZE is a power of 2 */ + BUILD_BUG_ON(RX_QUEUE_SIZE & (RX_QUEUE_SIZE - 1)); + + /* + * There can be up to (RX_QUEUE_SIZE - 1) free slots, to avoid ambiguity + * between empty and completely full queues. + * The following is equivalent to modulo by RX_QUEUE_SIZE and is well + * defined for negative dividends. + */ + return (rxq->read - rxq->write - 1) & (RX_QUEUE_SIZE - 1); +} + +/* + * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr + */ +static inline __le32 iwl_pcie_dma_addr2rbd_ptr(dma_addr_t dma_addr) +{ + return cpu_to_le32((u32)(dma_addr >> 8)); +} + +/* + * iwl_pcie_rx_stop - stops the Rx DMA + */ +int iwl_pcie_rx_stop(struct iwl_trans *trans) +{ + iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0); + return iwl_poll_direct_bit(trans, FH_MEM_RSSR_RX_STATUS_REG, + FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000); +} + +/* + * iwl_pcie_rxq_inc_wr_ptr - Update the write pointer for the RX queue + */ +static void iwl_pcie_rxq_inc_wr_ptr(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + u32 reg; + + lockdep_assert_held(&rxq->lock); + + /* + * explicitly wake up the NIC if: + * 1. shadow registers aren't enabled + * 2. there is a chance that the NIC is asleep + */ + if (!trans->cfg->base_params->shadow_reg_enable && + test_bit(STATUS_TPOWER_PMI, &trans->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); + rxq->need_update = true; + return; + } + } + + rxq->write_actual = round_down(rxq->write, 8); + iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual); +} + +static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + + spin_lock(&rxq->lock); + + if (!rxq->need_update) + goto exit_unlock; + + iwl_pcie_rxq_inc_wr_ptr(trans); + rxq->need_update = false; + + exit_unlock: + spin_unlock(&rxq->lock); +} + +/* + * iwl_pcie_rxq_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 iwl_pcie_rxq_restock(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_rx_mem_buffer *rxb; + + /* + * If the device isn't enabled - not need to try to add buffers... + * This can happen when we stop the device and still have an interrupt + * pending. We stop the APM before we sync the interrupts because we + * have to (see comment there). On the other hand, since the APM is + * stopped, we cannot access the HW (in particular not prph). + * So don't try to restock if the APM has been already stopped. + */ + if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status)) + return; + + spin_lock(&rxq->lock); + while ((iwl_rxq_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 */ + rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer, + list); + list_del(&rxb->list); + + /* Point to Rx buffer via next RBD in circular buffer */ + rxq->bd[rxq->write] = iwl_pcie_dma_addr2rbd_ptr(rxb->page_dma); + rxq->queue[rxq->write] = rxb; + rxq->write = (rxq->write + 1) & RX_QUEUE_MASK; + rxq->free_count--; + } + spin_unlock(&rxq->lock); + + /* 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(&rxq->lock); + iwl_pcie_rxq_inc_wr_ptr(trans); + spin_unlock(&rxq->lock); + } +} + +/* + * iwl_pcie_rx_alloc_page - allocates and returns a page. + * + */ +static struct page *iwl_pcie_rx_alloc_page(struct iwl_trans *trans, + gfp_t priority) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct page *page; + gfp_t gfp_mask = priority; + + 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); + /* Issue an error if the hardware has consumed more than half + * of its free buffer list and we don't have enough + * pre-allocated buffers. +` */ + if (rxq->free_count <= RX_LOW_WATERMARK && + iwl_rxq_space(rxq) > (RX_QUEUE_SIZE / 2) && + net_ratelimit()) + IWL_CRIT(trans, + "Failed to alloc_pages with GFP_KERNEL. Only %u free buffers remaining.\n", + rxq->free_count); + return NULL; + } + return page; +} + +/* + * iwl_pcie_rxq_alloc_rbs - allocate a page for each used RBD + * + * A used RBD is an Rx buffer that has been given to the stack. To use it again + * a page must be allocated and the RBD must point to the page. This function + * doesn't change the HW pointer but handles the list of pages that is used by + * iwl_pcie_rxq_restock. The latter function will update the HW to use the newly + * allocated buffers. + */ +static void iwl_pcie_rxq_alloc_rbs(struct iwl_trans *trans, gfp_t priority) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_rx_mem_buffer *rxb; + struct page *page; + + while (1) { + spin_lock(&rxq->lock); + if (list_empty(&rxq->rx_used)) { + spin_unlock(&rxq->lock); + return; + } + spin_unlock(&rxq->lock); + + /* Alloc a new receive buffer */ + page = iwl_pcie_rx_alloc_page(trans, priority); + if (!page) + return; + + spin_lock(&rxq->lock); + + if (list_empty(&rxq->rx_used)) { + spin_unlock(&rxq->lock); + __free_pages(page, trans_pcie->rx_page_order); + return; + } + rxb = list_first_entry(&rxq->rx_used, struct iwl_rx_mem_buffer, + list); + list_del(&rxb->list); + spin_unlock(&rxq->lock); + + 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); + if (dma_mapping_error(trans->dev, rxb->page_dma)) { + rxb->page = NULL; + spin_lock(&rxq->lock); + list_add(&rxb->list, &rxq->rx_used); + spin_unlock(&rxq->lock); + __free_pages(page, trans_pcie->rx_page_order); + return; + } + /* 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(&rxq->lock); + + list_add_tail(&rxb->list, &rxq->rx_free); + rxq->free_count++; + + spin_unlock(&rxq->lock); + } +} + +static void iwl_pcie_rxq_free_rbs(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + int i; + + lockdep_assert_held(&rxq->lock); + + for (i = 0; i < RX_QUEUE_SIZE; i++) { + if (!rxq->pool[i].page) + continue; + dma_unmap_page(trans->dev, rxq->pool[i].page_dma, + PAGE_SIZE << trans_pcie->rx_page_order, + DMA_FROM_DEVICE); + __free_pages(rxq->pool[i].page, trans_pcie->rx_page_order); + rxq->pool[i].page = NULL; + } +} + +/* + * iwl_pcie_rx_replenish - Move all used buffers from rx_used to rx_free + * + * When moving to rx_free an page is allocated for the slot. + * + * Also restock the Rx queue via iwl_pcie_rxq_restock. + * This is called only during initialization + */ +static void iwl_pcie_rx_replenish(struct iwl_trans *trans) +{ + iwl_pcie_rxq_alloc_rbs(trans, GFP_KERNEL); + + iwl_pcie_rxq_restock(trans); +} + +/* + * iwl_pcie_rx_allocator - Allocates pages in the background for RX queues + * + * Allocates for each received request 8 pages + * Called as a scheduled work item. + */ +static void iwl_pcie_rx_allocator(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rb_allocator *rba = &trans_pcie->rba; + struct list_head local_empty; + int pending = atomic_xchg(&rba->req_pending, 0); + + IWL_DEBUG_RX(trans, "Pending allocation requests = %d\n", pending); + + /* If we were scheduled - there is at least one request */ + spin_lock(&rba->lock); + /* swap out the rba->rbd_empty to a local list */ + list_replace_init(&rba->rbd_empty, &local_empty); + spin_unlock(&rba->lock); + + while (pending) { + int i; + struct list_head local_allocated; + + INIT_LIST_HEAD(&local_allocated); + + for (i = 0; i < RX_CLAIM_REQ_ALLOC;) { + struct iwl_rx_mem_buffer *rxb; + struct page *page; + + /* List should never be empty - each reused RBD is + * returned to the list, and initial pool covers any + * possible gap between the time the page is allocated + * to the time the RBD is added. + */ + BUG_ON(list_empty(&local_empty)); + /* Get the first rxb from the rbd list */ + rxb = list_first_entry(&local_empty, + struct iwl_rx_mem_buffer, list); + BUG_ON(rxb->page); + + /* Alloc a new receive buffer */ + page = iwl_pcie_rx_alloc_page(trans, GFP_KERNEL); + if (!page) + continue; + 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); + if (dma_mapping_error(trans->dev, rxb->page_dma)) { + rxb->page = NULL; + __free_pages(page, trans_pcie->rx_page_order); + continue; + } + /* 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)); + + /* move the allocated entry to the out list */ + list_move(&rxb->list, &local_allocated); + i++; + } + + pending--; + if (!pending) { + pending = atomic_xchg(&rba->req_pending, 0); + IWL_DEBUG_RX(trans, + "Pending allocation requests = %d\n", + pending); + } + + spin_lock(&rba->lock); + /* add the allocated rbds to the allocator allocated list */ + list_splice_tail(&local_allocated, &rba->rbd_allocated); + /* get more empty RBDs for current pending requests */ + list_splice_tail_init(&rba->rbd_empty, &local_empty); + spin_unlock(&rba->lock); + + atomic_inc(&rba->req_ready); + } + + spin_lock(&rba->lock); + /* return unused rbds to the allocator empty list */ + list_splice_tail(&local_empty, &rba->rbd_empty); + spin_unlock(&rba->lock); +} + +/* + * iwl_pcie_rx_allocator_get - Returns the pre-allocated pages +.* +.* Called by queue when the queue posted allocation request and + * has freed 8 RBDs in order to restock itself. + */ +static int iwl_pcie_rx_allocator_get(struct iwl_trans *trans, + struct iwl_rx_mem_buffer + *out[RX_CLAIM_REQ_ALLOC]) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rb_allocator *rba = &trans_pcie->rba; + int i; + + /* + * atomic_dec_if_positive returns req_ready - 1 for any scenario. + * If req_ready is 0 atomic_dec_if_positive will return -1 and this + * function will return -ENOMEM, as there are no ready requests. + * atomic_dec_if_positive will perofrm the *actual* decrement only if + * req_ready > 0, i.e. - there are ready requests and the function + * hands one request to the caller. + */ + if (atomic_dec_if_positive(&rba->req_ready) < 0) + return -ENOMEM; + + spin_lock(&rba->lock); + for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) { + /* Get next free Rx buffer, remove it from free list */ + out[i] = list_first_entry(&rba->rbd_allocated, + struct iwl_rx_mem_buffer, list); + list_del(&out[i]->list); + } + spin_unlock(&rba->lock); + + return 0; +} + +static void iwl_pcie_rx_allocator_work(struct work_struct *data) +{ + struct iwl_rb_allocator *rba_p = + container_of(data, struct iwl_rb_allocator, rx_alloc); + struct iwl_trans_pcie *trans_pcie = + container_of(rba_p, struct iwl_trans_pcie, rba); + + iwl_pcie_rx_allocator(trans_pcie->trans); +} + +static int iwl_pcie_rx_alloc(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_rb_allocator *rba = &trans_pcie->rba; + struct device *dev = trans->dev; + + memset(&trans_pcie->rxq, 0, sizeof(trans_pcie->rxq)); + + spin_lock_init(&rxq->lock); + spin_lock_init(&rba->lock); + + if (WARN_ON(rxq->bd || rxq->rb_stts)) + return -EINVAL; + + /* Allocate the circular buffer of Read Buffer Descriptors (RBDs) */ + rxq->bd = dma_zalloc_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE, + &rxq->bd_dma, GFP_KERNEL); + if (!rxq->bd) + goto err_bd; + + /*Allocate the driver's pointer to receive buffer status */ + rxq->rb_stts = dma_zalloc_coherent(dev, sizeof(*rxq->rb_stts), + &rxq->rb_stts_dma, GFP_KERNEL); + if (!rxq->rb_stts) + goto err_rb_stts; + + return 0; + +err_rb_stts: + dma_free_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE, + rxq->bd, rxq->bd_dma); + rxq->bd_dma = 0; + rxq->bd = NULL; +err_bd: + return -ENOMEM; +} + +static void iwl_pcie_rx_hw_init(struct iwl_trans *trans, struct iwl_rxq *rxq) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + u32 rb_size; + const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */ + + switch (trans_pcie->rx_buf_size) { + case IWL_AMSDU_4K: + rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K; + break; + case IWL_AMSDU_8K: + rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K; + break; + case IWL_AMSDU_12K: + rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_12K; + break; + default: + WARN_ON(1); + rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K; + } + + /* Stop Rx DMA */ + iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0); + /* reset and flush pointers */ + iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_RBDCB_WPTR, 0); + iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_FLUSH_RB_REQ, 0); + iwl_write_direct32(trans, FH_RSCSR_CHNL0_RDPTR, 0); + + /* Reset driver's Rx queue write index */ + iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0); + + /* Tell device where to find RBD circular buffer in DRAM */ + iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG, + (u32)(rxq->bd_dma >> 8)); + + /* Tell device where in DRAM to update its Rx status */ + iwl_write_direct32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG, + rxq->rb_stts_dma >> 4); + + /* Enable Rx DMA + * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in + * the credit mechanism in 5000 HW RX FIFO + * Direct rx interrupts to hosts + * Rx buffer size 4 or 8k or 12k + * RB timeout 0x10 + * 256 RBDs + */ + iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, + FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL | + FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY | + FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL | + rb_size| + (RX_RB_TIMEOUT << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)| + (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS)); + + /* Set interrupt coalescing timer to default (2048 usecs) */ + iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF); + + /* W/A for interrupt coalescing bug in 7260 and 3160 */ + if (trans->cfg->host_interrupt_operation_mode) + iwl_set_bit(trans, CSR_INT_COALESCING, IWL_HOST_INT_OPER_MODE); +} + +static void iwl_pcie_rx_init_rxb_lists(struct iwl_rxq *rxq) +{ + int i; + + lockdep_assert_held(&rxq->lock); + + INIT_LIST_HEAD(&rxq->rx_free); + INIT_LIST_HEAD(&rxq->rx_used); + rxq->free_count = 0; + rxq->used_count = 0; + + for (i = 0; i < RX_QUEUE_SIZE; i++) + list_add(&rxq->pool[i].list, &rxq->rx_used); +} + +static void iwl_pcie_rx_init_rba(struct iwl_rb_allocator *rba) +{ + int i; + + lockdep_assert_held(&rba->lock); + + INIT_LIST_HEAD(&rba->rbd_allocated); + INIT_LIST_HEAD(&rba->rbd_empty); + + for (i = 0; i < RX_POOL_SIZE; i++) + list_add(&rba->pool[i].list, &rba->rbd_empty); +} + +static void iwl_pcie_rx_free_rba(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rb_allocator *rba = &trans_pcie->rba; + int i; + + lockdep_assert_held(&rba->lock); + + for (i = 0; i < RX_POOL_SIZE; i++) { + if (!rba->pool[i].page) + continue; + dma_unmap_page(trans->dev, rba->pool[i].page_dma, + PAGE_SIZE << trans_pcie->rx_page_order, + DMA_FROM_DEVICE); + __free_pages(rba->pool[i].page, trans_pcie->rx_page_order); + rba->pool[i].page = NULL; + } +} + +int iwl_pcie_rx_init(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_rb_allocator *rba = &trans_pcie->rba; + int i, err; + + if (!rxq->bd) { + err = iwl_pcie_rx_alloc(trans); + if (err) + return err; + } + if (!rba->alloc_wq) + rba->alloc_wq = alloc_workqueue("rb_allocator", + WQ_HIGHPRI | WQ_UNBOUND, 1); + INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work); + + spin_lock(&rba->lock); + atomic_set(&rba->req_pending, 0); + atomic_set(&rba->req_ready, 0); + /* free all first - we might be reconfigured for a different size */ + iwl_pcie_rx_free_rba(trans); + iwl_pcie_rx_init_rba(rba); + spin_unlock(&rba->lock); + + spin_lock(&rxq->lock); + + /* free all first - we might be reconfigured for a different size */ + iwl_pcie_rxq_free_rbs(trans); + iwl_pcie_rx_init_rxb_lists(rxq); + + for (i = 0; i < RX_QUEUE_SIZE; i++) + rxq->queue[i] = NULL; + + /* Set us so that we have processed and used all buffers, but have + * not restocked the Rx queue with fresh buffers */ + rxq->read = rxq->write = 0; + rxq->write_actual = 0; + memset(rxq->rb_stts, 0, sizeof(*rxq->rb_stts)); + spin_unlock(&rxq->lock); + + iwl_pcie_rx_replenish(trans); + + iwl_pcie_rx_hw_init(trans, rxq); + + spin_lock(&rxq->lock); + iwl_pcie_rxq_inc_wr_ptr(trans); + spin_unlock(&rxq->lock); + + return 0; +} + +void iwl_pcie_rx_free(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_rb_allocator *rba = &trans_pcie->rba; + + /*if rxq->bd is NULL, it means that nothing has been allocated, + * exit now */ + if (!rxq->bd) { + IWL_DEBUG_INFO(trans, "Free NULL rx context\n"); + return; + } + + cancel_work_sync(&rba->rx_alloc); + if (rba->alloc_wq) { + destroy_workqueue(rba->alloc_wq); + rba->alloc_wq = NULL; + } + + spin_lock(&rba->lock); + iwl_pcie_rx_free_rba(trans); + spin_unlock(&rba->lock); + + spin_lock(&rxq->lock); + iwl_pcie_rxq_free_rbs(trans); + spin_unlock(&rxq->lock); + + dma_free_coherent(trans->dev, sizeof(__le32) * RX_QUEUE_SIZE, + rxq->bd, rxq->bd_dma); + rxq->bd_dma = 0; + rxq->bd = NULL; + + if (rxq->rb_stts) + dma_free_coherent(trans->dev, + sizeof(struct iwl_rb_status), + rxq->rb_stts, rxq->rb_stts_dma); + else + IWL_DEBUG_INFO(trans, "Free rxq->rb_stts which is NULL\n"); + rxq->rb_stts_dma = 0; + rxq->rb_stts = NULL; +} + +/* + * iwl_pcie_rx_reuse_rbd - Recycle used RBDs + * + * Called when a RBD can be reused. The RBD is transferred to the allocator. + * When there are 2 empty RBDs - a request for allocation is posted + */ +static void iwl_pcie_rx_reuse_rbd(struct iwl_trans *trans, + struct iwl_rx_mem_buffer *rxb, + struct iwl_rxq *rxq, bool emergency) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rb_allocator *rba = &trans_pcie->rba; + + /* Move the RBD to the used list, will be moved to allocator in batches + * before claiming or posting a request*/ + list_add_tail(&rxb->list, &rxq->rx_used); + + if (unlikely(emergency)) + return; + + /* Count the allocator owned RBDs */ + rxq->used_count++; + + /* If we have RX_POST_REQ_ALLOC new released rx buffers - + * issue a request for allocator. Modulo RX_CLAIM_REQ_ALLOC is + * used for the case we failed to claim RX_CLAIM_REQ_ALLOC, + * after but we still need to post another request. + */ + if ((rxq->used_count % RX_CLAIM_REQ_ALLOC) == RX_POST_REQ_ALLOC) { + /* Move the 2 RBDs to the allocator ownership. + Allocator has another 6 from pool for the request completion*/ + spin_lock(&rba->lock); + list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty); + spin_unlock(&rba->lock); + + atomic_inc(&rba->req_pending); + queue_work(rba->alloc_wq, &rba->rx_alloc); + } +} + +static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans, + struct iwl_rx_mem_buffer *rxb, + bool emergency) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue]; + 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; + u16 sequence; + bool reclaim; + int index, cmd_index, len; + struct iwl_rx_cmd_buffer rxcb = { + ._offset = offset, + ._rx_page_order = trans_pcie->rx_page_order, + ._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, seq 0x%x)\n", + rxcb._offset, + iwl_get_cmd_string(trans, + iwl_cmd_id(pkt->hdr.cmd, + pkt->hdr.group_id, + 0)), + pkt->hdr.cmd, le16_to_cpu(pkt->hdr.sequence)); + + len = iwl_rx_packet_len(pkt); + len += sizeof(u32); /* account for status word */ + trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len); + trace_iwlwifi_dev_rx_data(trans->dev, trans, 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); + + iwl_op_mode_rx(trans->op_mode, &trans_pcie->napi, &rxcb); + + if (reclaim) { + kzfree(txq->entries[cmd_index].free_buf); + txq->entries[cmd_index].free_buf = NULL; + } + + /* + * 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_pcie_hcmd_complete(trans, &rxcb); + 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. */ + 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); + if (dma_mapping_error(trans->dev, rxb->page_dma)) { + /* + * free the page(s) as well to not break + * the invariant that the items on the used + * list have no page(s) + */ + __free_pages(rxb->page, trans_pcie->rx_page_order); + rxb->page = NULL; + iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency); + } else { + list_add_tail(&rxb->list, &rxq->rx_free); + rxq->free_count++; + } + } else + iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency); +} + +/* + * iwl_pcie_rx_handle - Main entry function for receiving responses from fw + */ +static void iwl_pcie_rx_handle(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + struct iwl_rxq *rxq = &trans_pcie->rxq; + u32 r, i, j, count = 0; + bool emergency = false; + +restart: + spin_lock(&rxq->lock); + /* 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(ACCESS_ONCE(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); + + while (i != r) { + struct iwl_rx_mem_buffer *rxb; + + if (unlikely(rxq->used_count == RX_QUEUE_SIZE / 2)) + emergency = true; + + rxb = rxq->queue[i]; + rxq->queue[i] = NULL; + + IWL_DEBUG_RX(trans, "rxbuf: HW = %d, SW = %d\n", r, i); + iwl_pcie_rx_handle_rb(trans, rxb, emergency); + + i = (i + 1) & RX_QUEUE_MASK; + + /* If we have RX_CLAIM_REQ_ALLOC released rx buffers - + * try to claim the pre-allocated buffers from the allocator */ + if (rxq->used_count >= RX_CLAIM_REQ_ALLOC) { + struct iwl_rb_allocator *rba = &trans_pcie->rba; + struct iwl_rx_mem_buffer *out[RX_CLAIM_REQ_ALLOC]; + + if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 && + !emergency) { + /* Add the remaining 6 empty RBDs + * for allocator use + */ + spin_lock(&rba->lock); + list_splice_tail_init(&rxq->rx_used, + &rba->rbd_empty); + spin_unlock(&rba->lock); + } + + /* If not ready - continue, will try to reclaim later. + * No need to reschedule work - allocator exits only on + * success */ + if (!iwl_pcie_rx_allocator_get(trans, out)) { + /* If success - then RX_CLAIM_REQ_ALLOC + * buffers were retrieved and should be added + * to free list */ + rxq->used_count -= RX_CLAIM_REQ_ALLOC; + for (j = 0; j < RX_CLAIM_REQ_ALLOC; j++) { + list_add_tail(&out[j]->list, + &rxq->rx_free); + rxq->free_count++; + } + } + } + if (emergency) { + count++; + if (count == 8) { + count = 0; + if (rxq->used_count < RX_QUEUE_SIZE / 3) + emergency = false; + spin_unlock(&rxq->lock); + iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC); + spin_lock(&rxq->lock); + } + } + /* handle restock for three cases, can be all of them at once: + * - we just pulled buffers from the allocator + * - we have 8+ unstolen pages accumulated + * - we are in emergency and allocated buffers + */ + if (rxq->free_count >= RX_CLAIM_REQ_ALLOC) { + rxq->read = i; + spin_unlock(&rxq->lock); + iwl_pcie_rxq_restock(trans); + goto restart; + } + } + + /* Backtrack one entry */ + rxq->read = i; + spin_unlock(&rxq->lock); + + /* + * handle a case where in emergency there are some unallocated RBDs. + * those RBDs are in the used list, but are not tracked by the queue's + * used_count which counts allocator owned RBDs. + * unallocated emergency RBDs must be allocated on exit, otherwise + * when called again the function may not be in emergency mode and + * they will be handed to the allocator with no tracking in the RBD + * allocator counters, which will lead to them never being claimed back + * by the queue. + * by allocating them here, they are now in the queue free list, and + * will be restocked by the next call of iwl_pcie_rxq_restock. + */ + if (unlikely(emergency && count)) + iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC); + + if (trans_pcie->napi.poll) + napi_gro_flush(&trans_pcie->napi, false); +} + +/* + * iwl_pcie_irq_handle_error - called for HW or SW error interrupt from card + */ +static void iwl_pcie_irq_handle_error(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + int i; + + /* W/A for WiFi/WiMAX coex and WiMAX own the RF */ + if (trans->cfg->internal_wimax_coex && + !trans->cfg->apmg_not_supported && + (!(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))) { + clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status); + iwl_op_mode_wimax_active(trans->op_mode); + wake_up(&trans_pcie->wait_command_queue); + return; + } + + iwl_pcie_dump_csr(trans); + iwl_dump_fh(trans, NULL); + + local_bh_disable(); + /* The STATUS_FW_ERROR bit is set in this function. This must happen + * before we wake up the command caller, to ensure a proper cleanup. */ + iwl_trans_fw_error(trans); + local_bh_enable(); + + for (i = 0; i < trans->cfg->base_params->num_of_queues; i++) + del_timer(&trans_pcie->txq[i].stuck_timer); + + clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status); + wake_up(&trans_pcie->wait_command_queue); +} + +static u32 iwl_pcie_int_cause_non_ict(struct iwl_trans *trans) +{ + u32 inta; + + lockdep_assert_held(&IWL_TRANS_GET_PCIE_TRANS(trans)->irq_lock); + + trace_iwlwifi_dev_irq(trans->dev); + + /* Discover which interrupts are active/pending */ + inta = iwl_read32(trans, CSR_INT); + + /* the thread will service interrupts and re-enable them */ + return inta; +} + +/* 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)) + +/* 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. + */ +static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + u32 inta; + u32 val = 0; + u32 read; + + trace_iwlwifi_dev_irq(trans->dev); + + /* 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) + return 0; + + /* + * 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 = + ((trans_pcie->ict_index + 1) & (ICT_COUNT - 1)); + + 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); + return inta; +} + +irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id) +{ + struct iwl_trans *trans = dev_id; + 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; + + lock_map_acquire(&trans->sync_cmd_lockdep_map); + + spin_lock(&trans_pcie->irq_lock); + + /* dram interrupt table not set yet, + * use legacy interrupt. + */ + if (likely(trans_pcie->use_ict)) + inta = iwl_pcie_int_cause_ict(trans); + else + inta = iwl_pcie_int_cause_non_ict(trans); + + if (iwl_have_debug_level(IWL_DL_ISR)) { + IWL_DEBUG_ISR(trans, + "ISR inta 0x%08x, enabled 0x%08x(sw), enabled(hw) 0x%08x, fh 0x%08x\n", + inta, trans_pcie->inta_mask, + iwl_read32(trans, CSR_INT_MASK), + iwl_read32(trans, CSR_FH_INT_STATUS)); + if (inta & (~trans_pcie->inta_mask)) + IWL_DEBUG_ISR(trans, + "We got a masked interrupt (0x%08x)\n", + inta & (~trans_pcie->inta_mask)); + } + + inta &= trans_pcie->inta_mask; + + /* + * 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 (unlikely(!inta)) { + IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n"); + /* + * Re-enable interrupts here since we don't + * have anything to service + */ + if (test_bit(STATUS_INT_ENABLED, &trans->status)) + iwl_enable_interrupts(trans); + spin_unlock(&trans_pcie->irq_lock); + lock_map_release(&trans->sync_cmd_lockdep_map); + return IRQ_NONE; + } + + if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) { + /* + * Hardware disappeared. It might have + * already raised an interrupt. + */ + IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta); + spin_unlock(&trans_pcie->irq_lock); + goto out; + } + + /* 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, inta | ~trans_pcie->inta_mask); + + if (iwl_have_debug_level(IWL_DL_ISR)) + IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n", + inta, iwl_read32(trans, CSR_INT_MASK)); + + spin_unlock(&trans_pcie->irq_lock); + + /* 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_pcie_irq_handle_error(trans); + + handled |= CSR_INT_BIT_HW_ERR; + + goto out; + } + + 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++; + } + } + + /* 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++; + + mutex_lock(&trans_pcie->mutex); + iwl_trans_pcie_rf_kill(trans, hw_rfkill); + mutex_unlock(&trans_pcie->mutex); + if (hw_rfkill) { + set_bit(STATUS_RFKILL, &trans->status); + if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE, + &trans->status)) + IWL_DEBUG_RF_KILL(trans, + "Rfkill while SYNC HCMD in flight\n"); + wake_up(&trans_pcie->wait_command_queue); + } else { + clear_bit(STATUS_RFKILL, &trans->status); + } + + 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_pcie_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_pcie_rxq_check_wrptr(trans); + iwl_pcie_txq_check_wrptrs(trans); + + 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); + + /* + * 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++; + + local_bh_disable(); + iwl_pcie_rx_handle(trans); + local_bh_enable(); + } + + /* 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->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); + +out: + lock_map_release(&trans->sync_cmd_lockdep_map); + return IRQ_HANDLED; +} + +/****************************************************************************** + * + * ICT functions + * + ******************************************************************************/ + +/* Free dram table */ +void iwl_pcie_free_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_pcie_alloc_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + + trans_pcie->ict_tbl = + dma_zalloc_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_pcie_free_ict(trans); + return -EINVAL; + } + + 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_pcie_reset_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + u32 val; + + if (!trans_pcie->ict_tbl) + return; + + spin_lock(&trans_pcie->irq_lock); + 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 | + CSR_DRAM_INIT_TBL_WRAP_CHECK | + CSR_DRAM_INIT_TBL_WRITE_POINTER; + + 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(&trans_pcie->irq_lock); +} + +/* Device is going down disable ict interrupt usage */ +void iwl_pcie_disable_ict(struct iwl_trans *trans) +{ + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); + + spin_lock(&trans_pcie->irq_lock); + trans_pcie->use_ict = false; + spin_unlock(&trans_pcie->irq_lock); +} + +irqreturn_t iwl_pcie_isr(int irq, void *data) +{ + struct iwl_trans *trans = data; + + if (!trans) + return IRQ_NONE; + + /* 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. + */ + iwl_write32(trans, CSR_INT_MASK, 0x00000000); + + return IRQ_WAKE_THREAD; +} |