- 根目录:
- drivers
- net
- wireless
- iwlwifi
- pcie
- rx.c
/******************************************************************************
*
* 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 <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"
/******************************************************************************
*
* 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 */
if (trans_pcie->rx_buf_size_8k)
rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
else
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
* 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,
get_cmd_string(trans_pcie, pkt->hdr.cmd),
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 (%p)\n",
r, i, rxb);
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;
}
IWL_DEBUG_ISR(trans, "ict dma addr %Lx ict vir addr %p\n",
(unsigned long long)trans_pcie->ict_tbl_dma,
trans_pcie->ict_tbl);
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;
}