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path: root/drivers/net/wireless/iwlwifi/iwl-agn-ict.c
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Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-agn-ict.c')
-rw-r--r--drivers/net/wireless/iwlwifi/iwl-agn-ict.c307
1 files changed, 307 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..a273e373b7b0
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-ict.c
@@ -0,0 +1,307 @@
+/******************************************************************************
+ *
+ * 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 <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;
+}