iwlwifi: change monitor DMA to be coherent

Allow access to the memory by the host and the device simultaneously.
This will be needed in some future patches.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
index a7896fcc44cf3f818db71ea8471cce0ecde8d6b7..98d8da03ccfc09ce2ccedd631ff724a51b0fbd59 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
@@ -464,7 +464,7 @@ struct iwl_self_init_dram {
  * @mutex: to protect stop_device / start_fw / start_hw
  * @cmd_in_flight: true when we have a host command in flight
  * @fw_mon_phys: physical address of the buffer for the firmware monitor
- * @fw_mon_page: points to the first page of the buffer for the firmware monitor
+ * @fw_mon_cpu_addr: address of the buffer for the firmware monitor
  * @fw_mon_size: size of the buffer for the firmware monitor
  * @msix_entries: array of MSI-X entries
  * @msix_enabled: true if managed to enable MSI-X
@@ -554,7 +554,7 @@ struct iwl_trans_pcie {
        bool ref_cmd_in_flight;
 
        dma_addr_t fw_mon_phys;
-       struct page *fw_mon_page;
+       void *fw_mon_cpu_addr;
        u32 fw_mon_size;
 
        struct msix_entry msix_entries[IWL_MAX_RX_HW_QUEUES];

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index 8925b10217d7d519b4cda74c11ae3ba47cf3ca43..d8aca7291614bc9ec2bc8aa2f67312a60e3df00a 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -187,14 +187,13 @@ static void iwl_pcie_free_fw_monitor(struct iwl_trans *trans)
 {
        struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 
-       if (!trans_pcie->fw_mon_page)
+       if (!trans_pcie->fw_mon_cpu_addr)
                return;
 
-       dma_unmap_page(trans->dev, trans_pcie->fw_mon_phys,
-                      trans_pcie->fw_mon_size, DMA_FROM_DEVICE);
-       __free_pages(trans_pcie->fw_mon_page,
-                    get_order(trans_pcie->fw_mon_size));
-       trans_pcie->fw_mon_page = NULL;
+       dma_free_coherent(trans->dev, trans_pcie->fw_mon_size,
+                         trans_pcie->fw_mon_cpu_addr,
+                         trans_pcie->fw_mon_phys);
+       trans_pcie->fw_mon_cpu_addr = NULL;
        trans_pcie->fw_mon_phys = 0;
        trans_pcie->fw_mon_size = 0;
 }
@@ -202,7 +201,7 @@ static void iwl_pcie_free_fw_monitor(struct iwl_trans *trans)
 void iwl_pcie_alloc_fw_monitor(struct iwl_trans *trans, u8 max_power)
 {
        struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
-       struct page *page = NULL;
+       void *cpu_addr = NULL;
        dma_addr_t phys;
        u32 size = 0;
        u8 power;
@@ -219,38 +218,25 @@ void iwl_pcie_alloc_fw_monitor(struct iwl_trans *trans, u8 max_power)
                 max_power))
                return;
 
-       if (trans_pcie->fw_mon_page) {
-               dma_sync_single_for_device(trans->dev, trans_pcie->fw_mon_phys,
-                                          trans_pcie->fw_mon_size,
-                                          DMA_FROM_DEVICE);
+       if (trans_pcie->fw_mon_cpu_addr)
                return;
-       }
 
        phys = 0;
        for (power = max_power; power >= 11; power--) {
-               int order;
-
                size = BIT(power);
-               order = get_order(size);
-               page = alloc_pages(__GFP_COMP | __GFP_NOWARN | __GFP_ZERO,
-                                  order);
-               if (!page)
+               cpu_addr = dma_alloc_coherent(trans->dev, size, &phys,
+                                             GFP_KERNEL | __GFP_NOWARN |
+                                             __GFP_ZERO | __GFP_COMP);
+               if (!cpu_addr)
                        continue;
 
-               phys = dma_map_page(trans->dev, page, 0, PAGE_SIZE << order,
-                                   DMA_FROM_DEVICE);
-               if (dma_mapping_error(trans->dev, phys)) {
-                       __free_pages(page, order);
-                       page = NULL;
-                       continue;
-               }
                IWL_INFO(trans,
-                        "Allocated 0x%08x bytes (order %d) for firmware monitor.\n",
-                        size, order);
+                        "Allocated 0x%08x bytes for firmware monitor.\n",
+                        size);
                break;
        }
 
-       if (WARN_ON_ONCE(!page))
+       if (WARN_ON_ONCE(!cpu_addr))
                return;
 
        if (power != max_power)
@@ -259,7 +245,7 @@ void iwl_pcie_alloc_fw_monitor(struct iwl_trans *trans, u8 max_power)
                        (unsigned long)BIT(power - 10),
                        (unsigned long)BIT(max_power - 10));
 
-       trans_pcie->fw_mon_page = page;
+       trans_pcie->fw_mon_cpu_addr = cpu_addr;
        trans_pcie->fw_mon_phys = phys;
        trans_pcie->fw_mon_size = size;
 }
@@ -2863,7 +2849,7 @@ iwl_trans_pcie_dump_monitor(struct iwl_trans *trans,
        struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
        u32 len = 0;
 
-       if ((trans_pcie->fw_mon_page &&
+       if ((trans_pcie->fw_mon_cpu_addr &&
             trans->cfg->device_family == IWL_DEVICE_FAMILY_7000) ||
            trans->dbg_dest_tlv) {
                struct iwl_fw_error_dump_fw_mon *fw_mon_data;
@@ -2891,19 +2877,9 @@ iwl_trans_pcie_dump_monitor(struct iwl_trans *trans,
                        cpu_to_le32(iwl_read_prph(trans, base));
 
                len += sizeof(**data) + sizeof(*fw_mon_data);
-               if (trans_pcie->fw_mon_page) {
-                       /*
-                        * The firmware is now asserted, it won't write anything
-                        * to the buffer. CPU can take ownership to fetch the
-                        * data. The buffer will be handed back to the device
-                        * before the firmware will be restarted.
-                        */
-                       dma_sync_single_for_cpu(trans->dev,
-                                               trans_pcie->fw_mon_phys,
-                                               trans_pcie->fw_mon_size,
-                                               DMA_FROM_DEVICE);
+               if (trans_pcie->fw_mon_cpu_addr) {
                        memcpy(fw_mon_data->data,
-                              page_address(trans_pcie->fw_mon_page),
+                              trans_pcie->fw_mon_cpu_addr,
                               trans_pcie->fw_mon_size);
 
                        monitor_len = trans_pcie->fw_mon_size;
@@ -2966,7 +2942,7 @@ static struct iwl_trans_dump_data
                cmdq->n_window * (sizeof(*txcmd) + TFD_MAX_PAYLOAD_SIZE);
 
        /* FW monitor */
-       if (trans_pcie->fw_mon_page) {
+       if (trans_pcie->fw_mon_cpu_addr) {
                len += sizeof(*data) + sizeof(struct iwl_fw_error_dump_fw_mon) +
                       trans_pcie->fw_mon_size;
                monitor_len = trans_pcie->fw_mon_size;