diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-agn-ict.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-agn-ict.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-ict.c b/drivers/net/wireless/iwlwifi/iwl-agn-ict.c new file mode 100644 index 000000000000..c92b2c0cbd91 --- /dev/null +++ b/drivers/net/wireless/iwlwifi/iwl-agn-ict.c @@ -0,0 +1,308 @@ +/****************************************************************************** + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 - 2010 Intel Corporation. All rights reserved. + * + * 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.GPL. + * + * Contact Information: + * Intel Linux Wireless <ilw@linux.intel.com> + * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 + *****************************************************************************/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/etherdevice.h> +#include <linux/sched.h> +#include <linux/gfp.h> +#include <net/mac80211.h> + +#include "iwl-dev.h" +#include "iwl-core.h" +#include "iwl-agn.h" +#include "iwl-helpers.h" + +#define ICT_COUNT (PAGE_SIZE/sizeof(u32)) + +/* Free dram table */ +void iwl_free_isr_ict(struct iwl_priv *priv) +{ + if (priv->_agn.ict_tbl_vir) { + dma_free_coherent(&priv->pci_dev->dev, + (sizeof(u32) * ICT_COUNT) + PAGE_SIZE, + priv->_agn.ict_tbl_vir, + priv->_agn.ict_tbl_dma); + priv->_agn.ict_tbl_vir = NULL; + } +} + + +/* allocate dram shared table it is a PAGE_SIZE aligned + * also reset all data related to ICT table interrupt. + */ +int iwl_alloc_isr_ict(struct iwl_priv *priv) +{ + + if (priv->cfg->use_isr_legacy) + return 0; + /* allocate shrared data table */ + priv->_agn.ict_tbl_vir = + dma_alloc_coherent(&priv->pci_dev->dev, + (sizeof(u32) * ICT_COUNT) + PAGE_SIZE, + &priv->_agn.ict_tbl_dma, GFP_KERNEL); + if (!priv->_agn.ict_tbl_vir) + return -ENOMEM; + + /* align table to PAGE_SIZE boundry */ + priv->_agn.aligned_ict_tbl_dma = ALIGN(priv->_agn.ict_tbl_dma, PAGE_SIZE); + + IWL_DEBUG_ISR(priv, "ict dma addr %Lx dma aligned %Lx diff %d\n", + (unsigned long long)priv->_agn.ict_tbl_dma, + (unsigned long long)priv->_agn.aligned_ict_tbl_dma, + (int)(priv->_agn.aligned_ict_tbl_dma - priv->_agn.ict_tbl_dma)); + + priv->_agn.ict_tbl = priv->_agn.ict_tbl_vir + + (priv->_agn.aligned_ict_tbl_dma - priv->_agn.ict_tbl_dma); + + IWL_DEBUG_ISR(priv, "ict vir addr %p vir aligned %p diff %d\n", + priv->_agn.ict_tbl, priv->_agn.ict_tbl_vir, + (int)(priv->_agn.aligned_ict_tbl_dma - priv->_agn.ict_tbl_dma)); + + /* reset table and index to all 0 */ + memset(priv->_agn.ict_tbl_vir,0, (sizeof(u32) * ICT_COUNT) + PAGE_SIZE); + priv->_agn.ict_index = 0; + + /* add periodic RX interrupt */ + priv->inta_mask |= CSR_INT_BIT_RX_PERIODIC; + return 0; +} + +/* Device is going up inform it about using ICT interrupt table, + * also we need to tell the driver to start using ICT interrupt. + */ +int iwl_reset_ict(struct iwl_priv *priv) +{ + u32 val; + unsigned long flags; + + if (!priv->_agn.ict_tbl_vir) + return 0; + + spin_lock_irqsave(&priv->lock, flags); + iwl_disable_interrupts(priv); + + memset(&priv->_agn.ict_tbl[0], 0, sizeof(u32) * ICT_COUNT); + + val = priv->_agn.aligned_ict_tbl_dma >> PAGE_SHIFT; + + val |= CSR_DRAM_INT_TBL_ENABLE; + val |= CSR_DRAM_INIT_TBL_WRAP_CHECK; + + IWL_DEBUG_ISR(priv, "CSR_DRAM_INT_TBL_REG =0x%X " + "aligned dma address %Lx\n", + val, (unsigned long long)priv->_agn.aligned_ict_tbl_dma); + + iwl_write32(priv, CSR_DRAM_INT_TBL_REG, val); + priv->_agn.use_ict = true; + priv->_agn.ict_index = 0; + iwl_write32(priv, CSR_INT, priv->inta_mask); + iwl_enable_interrupts(priv); + spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +/* Device is going down disable ict interrupt usage */ +void iwl_disable_ict(struct iwl_priv *priv) +{ + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + priv->_agn.use_ict = false; + spin_unlock_irqrestore(&priv->lock, flags); +} + +static irqreturn_t iwl_isr(int irq, void *data) +{ + struct iwl_priv *priv = data; + u32 inta, inta_mask; + unsigned long flags; +#ifdef CONFIG_IWLWIFI_DEBUG + u32 inta_fh; +#endif + if (!priv) + return IRQ_NONE; + + spin_lock_irqsave(&priv->lock, flags); + + /* Disable (but don't clear!) interrupts here to avoid + * back-to-back ISRs and sporadic interrupts from our NIC. + * If we have something to service, the tasklet will re-enable ints. + * If we *don't* have something, we'll re-enable before leaving here. */ + inta_mask = iwl_read32(priv, CSR_INT_MASK); /* just for debug */ + iwl_write32(priv, CSR_INT_MASK, 0x00000000); + + /* Discover which interrupts are active/pending */ + inta = iwl_read32(priv, CSR_INT); + + /* Ignore interrupt if there's nothing in NIC to service. + * This may be due to IRQ shared with another device, + * or due to sporadic interrupts thrown from our NIC. */ + if (!inta) { + IWL_DEBUG_ISR(priv, "Ignore interrupt, inta == 0\n"); + goto none; + } + + if ((inta == 0xFFFFFFFF) || ((inta & 0xFFFFFFF0) == 0xa5a5a5a0)) { + /* Hardware disappeared. It might have already raised + * an interrupt */ + IWL_WARN(priv, "HARDWARE GONE?? INTA == 0x%08x\n", inta); + goto unplugged; + } + +#ifdef CONFIG_IWLWIFI_DEBUG + if (iwl_get_debug_level(priv) & (IWL_DL_ISR)) { + inta_fh = iwl_read32(priv, CSR_FH_INT_STATUS); + IWL_DEBUG_ISR(priv, "ISR inta 0x%08x, enabled 0x%08x, " + "fh 0x%08x\n", inta, inta_mask, inta_fh); + } +#endif + + priv->_agn.inta |= inta; + /* iwl_irq_tasklet() will service interrupts and re-enable them */ + if (likely(inta)) + tasklet_schedule(&priv->irq_tasklet); + else if (test_bit(STATUS_INT_ENABLED, &priv->status) && !priv->_agn.inta) + iwl_enable_interrupts(priv); + + unplugged: + spin_unlock_irqrestore(&priv->lock, flags); + return IRQ_HANDLED; + + none: + /* re-enable interrupts here since we don't have anything to service. */ + /* only Re-enable if diabled by irq and no schedules tasklet. */ + if (test_bit(STATUS_INT_ENABLED, &priv->status) && !priv->_agn.inta) + iwl_enable_interrupts(priv); + + spin_unlock_irqrestore(&priv->lock, flags); + return IRQ_NONE; +} + +/* interrupt handler using ict table, with this interrupt driver will + * stop using INTA register to get device's interrupt, reading this register + * is expensive, device will write interrupts in ICT dram table, increment + * index then will fire interrupt to driver, driver will OR all ICT table + * entries from current index up to table entry with 0 value. the result is + * the interrupt we need to service, driver will set the entries back to 0 and + * set index. + */ +irqreturn_t iwl_isr_ict(int irq, void *data) +{ + struct iwl_priv *priv = data; + u32 inta, inta_mask; + u32 val = 0; + unsigned long flags; + + if (!priv) + return IRQ_NONE; + + /* dram interrupt table not set yet, + * use legacy interrupt. + */ + if (!priv->_agn.use_ict) + return iwl_isr(irq, data); + + spin_lock_irqsave(&priv->lock, flags); + + /* Disable (but don't clear!) interrupts here to avoid + * back-to-back ISRs and sporadic interrupts from our NIC. + * If we have something to service, the tasklet will re-enable ints. + * If we *don't* have something, we'll re-enable before leaving here. + */ + inta_mask = iwl_read32(priv, CSR_INT_MASK); /* just for debug */ + iwl_write32(priv, CSR_INT_MASK, 0x00000000); + + + /* Ignore interrupt if there's nothing in NIC to service. + * This may be due to IRQ shared with another device, + * or due to sporadic interrupts thrown from our NIC. */ + if (!priv->_agn.ict_tbl[priv->_agn.ict_index]) { + IWL_DEBUG_ISR(priv, "Ignore interrupt, inta == 0\n"); + goto none; + } + + /* read all entries that not 0 start with ict_index */ + while (priv->_agn.ict_tbl[priv->_agn.ict_index]) { + + val |= le32_to_cpu(priv->_agn.ict_tbl[priv->_agn.ict_index]); + IWL_DEBUG_ISR(priv, "ICT index %d value 0x%08X\n", + priv->_agn.ict_index, + le32_to_cpu(priv->_agn.ict_tbl[priv->_agn.ict_index])); + priv->_agn.ict_tbl[priv->_agn.ict_index] = 0; + priv->_agn.ict_index = iwl_queue_inc_wrap(priv->_agn.ict_index, + ICT_COUNT); + + } + + /* We should not get this value, just ignore it. */ + if (val == 0xffffffff) + val = 0; + + /* + * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit + * (bit 15 before shifting it to 31) to clear when using interrupt + * coalescing. fortunately, bits 18 and 19 stay set when this happens + * so we use them to decide on the real state of the Rx bit. + * In order words, bit 15 is set if bit 18 or bit 19 are set. + */ + if (val & 0xC0000) + val |= 0x8000; + + inta = (0xff & val) | ((0xff00 & val) << 16); + IWL_DEBUG_ISR(priv, "ISR inta 0x%08x, enabled 0x%08x ict 0x%08x\n", + inta, inta_mask, val); + + inta &= priv->inta_mask; + priv->_agn.inta |= inta; + + /* iwl_irq_tasklet() will service interrupts and re-enable them */ + if (likely(inta)) + tasklet_schedule(&priv->irq_tasklet); + else if (test_bit(STATUS_INT_ENABLED, &priv->status) && !priv->_agn.inta) { + /* Allow interrupt if was disabled by this handler and + * no tasklet was schedules, We should not enable interrupt, + * tasklet will enable it. + */ + iwl_enable_interrupts(priv); + } + + spin_unlock_irqrestore(&priv->lock, flags); + return IRQ_HANDLED; + + none: + /* re-enable interrupts here since we don't have anything to service. + * only Re-enable if disabled by irq. + */ + if (test_bit(STATUS_INT_ENABLED, &priv->status) && !priv->_agn.inta) + iwl_enable_interrupts(priv); + + spin_unlock_irqrestore(&priv->lock, flags); + return IRQ_NONE; +} |