--- /dev/null
+/*
+ * Device handling thread implementation for mac80211 ST-Ericsson CW1200 drivers
+ *
+ * Copyright (c) 2010, ST-Ericsson
+ * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
+ *
+ * Based on:
+ * ST-Ericsson UMAC CW1200 driver, which is
+ * Copyright (c) 2010, ST-Ericsson
+ * Author: Ajitpal Singh <ajitpal.singh@stericsson.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <net/mac80211.h>
+#include <linux/kthread.h>
+#include <linux/timer.h>
+
+#include "cw1200.h"
+#include "bh.h"
+#include "hwio.h"
+#include "wsm.h"
+#include "hwbus.h"
+#include "debug.h"
+#include "fwio.h"
+
+static int cw1200_bh(void *arg);
+
+#define DOWNLOAD_BLOCK_SIZE_WR (0x1000 - 4)
+/* an SPI message cannot be bigger than (2"12-1)*2 bytes
+ * "*2" to cvt to bytes
+ */
+#define MAX_SZ_RD_WR_BUFFERS (DOWNLOAD_BLOCK_SIZE_WR*2)
+#define PIGGYBACK_CTRL_REG (2)
+#define EFFECTIVE_BUF_SIZE (MAX_SZ_RD_WR_BUFFERS - PIGGYBACK_CTRL_REG)
+
+/* Suspend state privates */
+enum cw1200_bh_pm_state {
+ CW1200_BH_RESUMED = 0,
+ CW1200_BH_SUSPEND,
+ CW1200_BH_SUSPENDED,
+ CW1200_BH_RESUME,
+};
+
+typedef int (*cw1200_wsm_handler)(struct cw1200_common *priv,
+ u8 *data, size_t size);
+
+static void cw1200_bh_work(struct work_struct *work)
+{
+ struct cw1200_common *priv =
+ container_of(work, struct cw1200_common, bh_work);
+ cw1200_bh(priv);
+}
+
+int cw1200_register_bh(struct cw1200_common *priv)
+{
+ int err = 0;
+ /* Realtime workqueue */
+ priv->bh_workqueue = alloc_workqueue("cw1200_bh",
+ WQ_MEM_RECLAIM | WQ_HIGHPRI
+ | WQ_CPU_INTENSIVE, 1);
+
+ if (!priv->bh_workqueue)
+ return -ENOMEM;
+
+ INIT_WORK(&priv->bh_work, cw1200_bh_work);
+
+ pr_debug("[BH] register.\n");
+
+ atomic_set(&priv->bh_rx, 0);
+ atomic_set(&priv->bh_tx, 0);
+ atomic_set(&priv->bh_term, 0);
+ atomic_set(&priv->bh_suspend, CW1200_BH_RESUMED);
+ priv->bh_error = 0;
+ priv->hw_bufs_used = 0;
+ priv->buf_id_tx = 0;
+ priv->buf_id_rx = 0;
+ init_waitqueue_head(&priv->bh_wq);
+ init_waitqueue_head(&priv->bh_evt_wq);
+
+ err = !queue_work(priv->bh_workqueue, &priv->bh_work);
+ WARN_ON(err);
+ return err;
+}
+
+void cw1200_unregister_bh(struct cw1200_common *priv)
+{
+ atomic_add(1, &priv->bh_term);
+ wake_up(&priv->bh_wq);
+
+ flush_workqueue(priv->bh_workqueue);
+
+ destroy_workqueue(priv->bh_workqueue);
+ priv->bh_workqueue = NULL;
+
+ pr_debug("[BH] unregistered.\n");
+}
+
+void cw1200_irq_handler(struct cw1200_common *priv)
+{
+ pr_debug("[BH] irq.\n");
+
+ /* Disable Interrupts! */
+ /* NOTE: hwbus_ops->lock already held */
+ __cw1200_irq_enable(priv, 0);
+
+ if (/* WARN_ON */(priv->bh_error))
+ return;
+
+ if (atomic_add_return(1, &priv->bh_rx) == 1)
+ wake_up(&priv->bh_wq);
+}
+EXPORT_SYMBOL_GPL(cw1200_irq_handler);
+
+void cw1200_bh_wakeup(struct cw1200_common *priv)
+{
+ pr_debug("[BH] wakeup.\n");
+ if (priv->bh_error) {
+ pr_err("[BH] wakeup failed (BH error)\n");
+ return;
+ }
+
+ if (atomic_add_return(1, &priv->bh_tx) == 1)
+ wake_up(&priv->bh_wq);
+}
+
+int cw1200_bh_suspend(struct cw1200_common *priv)
+{
+ pr_debug("[BH] suspend.\n");
+ if (priv->bh_error) {
+ wiphy_warn(priv->hw->wiphy, "BH error -- can't suspend\n");
+ return -EINVAL;
+ }
+
+ atomic_set(&priv->bh_suspend, CW1200_BH_SUSPEND);
+ wake_up(&priv->bh_wq);
+ return wait_event_timeout(priv->bh_evt_wq, priv->bh_error ||
+ (CW1200_BH_SUSPENDED == atomic_read(&priv->bh_suspend)),
+ 1 * HZ) ? 0 : -ETIMEDOUT;
+}
+
+int cw1200_bh_resume(struct cw1200_common *priv)
+{
+ pr_debug("[BH] resume.\n");
+ if (priv->bh_error) {
+ wiphy_warn(priv->hw->wiphy, "BH error -- can't resume\n");
+ return -EINVAL;
+ }
+
+ atomic_set(&priv->bh_suspend, CW1200_BH_RESUME);
+ wake_up(&priv->bh_wq);
+ return wait_event_timeout(priv->bh_evt_wq, priv->bh_error ||
+ (CW1200_BH_RESUMED == atomic_read(&priv->bh_suspend)),
+ 1 * HZ) ? 0 : -ETIMEDOUT;
+}
+
+static inline void wsm_alloc_tx_buffer(struct cw1200_common *priv)
+{
+ ++priv->hw_bufs_used;
+}
+
+int wsm_release_tx_buffer(struct cw1200_common *priv, int count)
+{
+ int ret = 0;
+ int hw_bufs_used = priv->hw_bufs_used;
+
+ priv->hw_bufs_used -= count;
+ if (WARN_ON(priv->hw_bufs_used < 0))
+ ret = -1;
+ else if (hw_bufs_used >= priv->wsm_caps.input_buffers)
+ ret = 1;
+ if (!priv->hw_bufs_used)
+ wake_up(&priv->bh_evt_wq);
+ return ret;
+}
+
+static int cw1200_bh_read_ctrl_reg(struct cw1200_common *priv,
+ u16 *ctrl_reg)
+{
+ int ret;
+
+ ret = cw1200_reg_read_16(priv,
+ ST90TDS_CONTROL_REG_ID, ctrl_reg);
+ if (ret) {
+ ret = cw1200_reg_read_16(priv,
+ ST90TDS_CONTROL_REG_ID, ctrl_reg);
+ if (ret)
+ pr_err("[BH] Failed to read control register.\n");
+ }
+
+ return ret;
+}
+
+static int cw1200_device_wakeup(struct cw1200_common *priv)
+{
+ u16 ctrl_reg;
+ int ret;
+
+ pr_debug("[BH] Device wakeup.\n");
+
+ /* First, set the dpll register */
+ ret = cw1200_reg_write_32(priv, ST90TDS_TSET_GEN_R_W_REG_ID,
+ cw1200_dpll_from_clk(priv->hw_refclk));
+ if (WARN_ON(ret))
+ return ret;
+
+ /* To force the device to be always-on, the host sets WLAN_UP to 1 */
+ ret = cw1200_reg_write_16(priv, ST90TDS_CONTROL_REG_ID,
+ ST90TDS_CONT_WUP_BIT);
+ if (WARN_ON(ret))
+ return ret;
+
+ ret = cw1200_bh_read_ctrl_reg(priv, &ctrl_reg);
+ if (WARN_ON(ret))
+ return ret;
+
+ /* If the device returns WLAN_RDY as 1, the device is active and will
+ * remain active.
+ */
+ if (ctrl_reg & ST90TDS_CONT_RDY_BIT) {
+ pr_debug("[BH] Device awake.\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Must be called from BH thraed. */
+void cw1200_enable_powersave(struct cw1200_common *priv,
+ bool enable)
+{
+ pr_debug("[BH] Powerave is %s.\n",
+ enable ? "enabled" : "disabled");
+ priv->powersave_enabled = enable;
+}
+
+static int cw1200_bh_rx_helper(struct cw1200_common *priv,
+ uint16_t *ctrl_reg,
+ int *tx)
+{
+ size_t read_len = 0;
+ struct sk_buff *skb_rx = NULL;
+ struct wsm_hdr *wsm;
+ size_t wsm_len;
+ u16 wsm_id;
+ u8 wsm_seq;
+ int rx_resync = 1;
+
+ size_t alloc_len;
+ u8 *data;
+
+ read_len = (*ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) * 2;
+ if (!read_len)
+ return 0; /* No more work */
+
+ if (WARN_ON((read_len < sizeof(struct wsm_hdr)) ||
+ (read_len > EFFECTIVE_BUF_SIZE))) {
+ pr_debug("Invalid read len: %zu (%04x)",
+ read_len, *ctrl_reg);
+ goto err;
+ }
+
+ /* Add SIZE of PIGGYBACK reg (CONTROL Reg)
+ * to the NEXT Message length + 2 Bytes for SKB
+ */
+ read_len = read_len + 2;
+
+ alloc_len = priv->hwbus_ops->align_size(
+ priv->hwbus_priv, read_len);
+
+ /* Check if not exceeding CW1200 capabilities */
+ if (WARN_ON_ONCE(alloc_len > EFFECTIVE_BUF_SIZE)) {
+ pr_debug("Read aligned len: %zu\n",
+ alloc_len);
+ }
+
+ skb_rx = dev_alloc_skb(alloc_len);
+ if (WARN_ON(!skb_rx))
+ goto err;
+
+ skb_trim(skb_rx, 0);
+ skb_put(skb_rx, read_len);
+ data = skb_rx->data;
+ if (WARN_ON(!data))
+ goto err;
+
+ if (WARN_ON(cw1200_data_read(priv, data, alloc_len))) {
+ pr_err("rx blew up, len %zu\n", alloc_len);
+ goto err;
+ }
+
+ /* Piggyback */
+ *ctrl_reg = __le16_to_cpu(
+ ((__le16 *)data)[alloc_len / 2 - 1]);
+
+ wsm = (struct wsm_hdr *)data;
+ wsm_len = __le16_to_cpu(wsm->len);
+ if (WARN_ON(wsm_len > read_len))
+ goto err;
+
+ if (priv->wsm_enable_wsm_dumps)
+ print_hex_dump_bytes("<-- ",
+ DUMP_PREFIX_NONE,
+ data, wsm_len);
+
+ wsm_id = __le16_to_cpu(wsm->id) & 0xFFF;
+ wsm_seq = (__le16_to_cpu(wsm->id) >> 13) & 7;
+
+ skb_trim(skb_rx, wsm_len);
+
+ if (wsm_id == 0x0800) {
+ wsm_handle_exception(priv,
+ &data[sizeof(*wsm)],
+ wsm_len - sizeof(*wsm));
+ goto err;
+ } else if (!rx_resync) {
+ if (WARN_ON(wsm_seq != priv->wsm_rx_seq))
+ goto err;
+ }
+ priv->wsm_rx_seq = (wsm_seq + 1) & 7;
+ rx_resync = 0;
+
+ if (wsm_id & 0x0400) {
+ int rc = wsm_release_tx_buffer(priv, 1);
+ if (WARN_ON(rc < 0))
+ return rc;
+ else if (rc > 0)
+ *tx = 1;
+ }
+
+ /* cw1200_wsm_rx takes care on SKB livetime */
+ if (WARN_ON(wsm_handle_rx(priv, wsm_id, wsm, &skb_rx)))
+ goto err;
+
+ if (skb_rx) {
+ dev_kfree_skb(skb_rx);
+ skb_rx = NULL;
+ }
+
+ return 0;
+
+err:
+ if (skb_rx) {
+ dev_kfree_skb(skb_rx);
+ skb_rx = NULL;
+ }
+ return -1;
+}
+
+static int cw1200_bh_tx_helper(struct cw1200_common *priv,
+ int *pending_tx,
+ int *tx_burst)
+{
+ size_t tx_len;
+ u8 *data;
+ int ret;
+ struct wsm_hdr *wsm;
+
+ if (priv->device_can_sleep) {
+ ret = cw1200_device_wakeup(priv);
+ if (WARN_ON(ret < 0)) { /* Error in wakeup */
+ *pending_tx = 1;
+ return 0;
+ } else if (ret) { /* Woke up */
+ priv->device_can_sleep = false;
+ } else { /* Did not awake */
+ *pending_tx = 1;
+ return 0;
+ }
+ }
+
+ wsm_alloc_tx_buffer(priv);
+ ret = wsm_get_tx(priv, &data, &tx_len, tx_burst);
+ if (ret <= 0) {
+ wsm_release_tx_buffer(priv, 1);
+ if (WARN_ON(ret < 0))
+ return ret; /* Error */
+ return 0; /* No work */
+ }
+
+ wsm = (struct wsm_hdr *)data;
+ BUG_ON(tx_len < sizeof(*wsm));
+ BUG_ON(__le16_to_cpu(wsm->len) != tx_len);
+
+ atomic_add(1, &priv->bh_tx);
+
+ tx_len = priv->hwbus_ops->align_size(
+ priv->hwbus_priv, tx_len);
+
+ /* Check if not exceeding CW1200 capabilities */
+ if (WARN_ON_ONCE(tx_len > EFFECTIVE_BUF_SIZE))
+ pr_debug("Write aligned len: %zu\n", tx_len);
+
+ wsm->id &= __cpu_to_le16(0xffff ^ WSM_TX_SEQ(WSM_TX_SEQ_MAX));
+ wsm->id |= __cpu_to_le16(WSM_TX_SEQ(priv->wsm_tx_seq));
+
+ if (WARN_ON(cw1200_data_write(priv, data, tx_len))) {
+ pr_err("tx blew up, len %zu\n", tx_len);
+ wsm_release_tx_buffer(priv, 1);
+ return -1; /* Error */
+ }
+
+ if (priv->wsm_enable_wsm_dumps)
+ print_hex_dump_bytes("--> ",
+ DUMP_PREFIX_NONE,
+ data,
+ __le16_to_cpu(wsm->len));
+
+ wsm_txed(priv, data);
+ priv->wsm_tx_seq = (priv->wsm_tx_seq + 1) & WSM_TX_SEQ_MAX;
+
+ if (*tx_burst > 1) {
+ cw1200_debug_tx_burst(priv);
+ return 1; /* Work remains */
+ }
+
+ return 0;
+}
+
+static int cw1200_bh(void *arg)
+{
+ struct cw1200_common *priv = arg;
+ int rx, tx, term, suspend;
+ u16 ctrl_reg = 0;
+ int tx_allowed;
+ int pending_tx = 0;
+ int tx_burst;
+ long status;
+ u32 dummy;
+ int ret;
+
+ for (;;) {
+ if (!priv->hw_bufs_used &&
+ priv->powersave_enabled &&
+ !priv->device_can_sleep &&
+ !atomic_read(&priv->recent_scan)) {
+ status = 1 * HZ;
+ pr_debug("[BH] Device wakedown. No data.\n");
+ cw1200_reg_write_16(priv, ST90TDS_CONTROL_REG_ID, 0);
+ priv->device_can_sleep = true;
+ } else if (priv->hw_bufs_used) {
+ /* Interrupt loss detection */
+ status = 1 * HZ;
+ } else {
+ status = MAX_SCHEDULE_TIMEOUT;
+ }
+
+ /* Dummy Read for SDIO retry mechanism*/
+ if ((priv->hw_type != -1) &&
+ (atomic_read(&priv->bh_rx) == 0) &&
+ (atomic_read(&priv->bh_tx) == 0))
+ cw1200_reg_read(priv, ST90TDS_CONFIG_REG_ID,
+ &dummy, sizeof(dummy));
+
+ pr_debug("[BH] waiting ...\n");
+ status = wait_event_interruptible_timeout(priv->bh_wq, ({
+ rx = atomic_xchg(&priv->bh_rx, 0);
+ tx = atomic_xchg(&priv->bh_tx, 0);
+ term = atomic_xchg(&priv->bh_term, 0);
+ suspend = pending_tx ?
+ 0 : atomic_read(&priv->bh_suspend);
+ (rx || tx || term || suspend || priv->bh_error);
+ }), status);
+
+ pr_debug("[BH] - rx: %d, tx: %d, term: %d, bh_err: %d, suspend: %d, status: %ld\n",
+ rx, tx, term, suspend, priv->bh_error, status);
+
+ /* Did an error occur? */
+ if ((status < 0 && status != -ERESTARTSYS) ||
+ term || priv->bh_error) {
+ break;
+ }
+ if (!status) { /* wait_event timed out */
+ unsigned long timestamp = jiffies;
+ long timeout;
+ int pending = 0;
+ int i;
+
+ /* Check to see if we have any outstanding frames */
+ if (priv->hw_bufs_used && (!rx || !tx)) {
+ wiphy_warn(priv->hw->wiphy,
+ "Missed interrupt? (%d frames outstanding)\n",
+ priv->hw_bufs_used);
+ rx = 1;
+
+ /* Get a timestamp of "oldest" frame */
+ for (i = 0; i < 4; ++i)
+ pending += cw1200_queue_get_xmit_timestamp(
+ &priv->tx_queue[i],
+ ×tamp,
+ priv->pending_frame_id);
+
+ /* Check if frame transmission is timed out.
+ * Add an extra second with respect to possible
+ * interrupt loss.
+ */
+ timeout = timestamp +
+ WSM_CMD_LAST_CHANCE_TIMEOUT +
+ 1 * HZ -
+ jiffies;
+
+ /* And terminate BH thread if the frame is "stuck" */
+ if (pending && timeout < 0) {
+ wiphy_warn(priv->hw->wiphy,
+ "Timeout waiting for TX confirm (%d/%d pending, %ld vs %lu).\n",
+ priv->hw_bufs_used, pending,
+ timestamp, jiffies);
+ break;
+ }
+ } else if (!priv->device_can_sleep &&
+ !atomic_read(&priv->recent_scan)) {
+ pr_debug("[BH] Device wakedown. Timeout.\n");
+ cw1200_reg_write_16(priv,
+ ST90TDS_CONTROL_REG_ID, 0);
+ priv->device_can_sleep = true;
+ }
+ goto done;
+ } else if (suspend) {
+ pr_debug("[BH] Device suspend.\n");
+ if (priv->powersave_enabled) {
+ pr_debug("[BH] Device wakedown. Suspend.\n");
+ cw1200_reg_write_16(priv,
+ ST90TDS_CONTROL_REG_ID, 0);
+ priv->device_can_sleep = true;
+ }
+
+ atomic_set(&priv->bh_suspend, CW1200_BH_SUSPENDED);
+ wake_up(&priv->bh_evt_wq);
+ status = wait_event_interruptible(priv->bh_wq,
+ CW1200_BH_RESUME == atomic_read(&priv->bh_suspend));
+ if (status < 0) {
+ wiphy_err(priv->hw->wiphy,
+ "Failed to wait for resume: %ld.\n",
+ status);
+ break;
+ }
+ pr_debug("[BH] Device resume.\n");
+ atomic_set(&priv->bh_suspend, CW1200_BH_RESUMED);
+ wake_up(&priv->bh_evt_wq);
+ atomic_add(1, &priv->bh_rx);
+ goto done;
+ }
+
+ rx:
+ tx += pending_tx;
+ pending_tx = 0;
+
+ if (cw1200_bh_read_ctrl_reg(priv, &ctrl_reg))
+ break;
+
+ /* Don't bother trying to rx unless we have data to read */
+ if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) {
+ ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx);
+ if (ret < 0)
+ break;
+ /* Double up here if there's more data.. */
+ if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) {
+ ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx);
+ if (ret < 0)
+ break;
+ }
+ }
+
+ tx:
+ if (tx) {
+ tx = 0;
+
+ BUG_ON(priv->hw_bufs_used > priv->wsm_caps.input_buffers);
+ tx_burst = priv->wsm_caps.input_buffers - priv->hw_bufs_used;
+ tx_allowed = tx_burst > 0;
+
+ if (!tx_allowed) {
+ /* Buffers full. Ensure we process tx
+ * after we handle rx..
+ */
+ pending_tx = tx;
+ goto done_rx;
+ }
+ ret = cw1200_bh_tx_helper(priv, &pending_tx, &tx_burst);
+ if (ret < 0)
+ break;
+ if (ret > 0) /* More to transmit */
+ tx = ret;
+
+ /* Re-read ctrl reg */
+ if (cw1200_bh_read_ctrl_reg(priv, &ctrl_reg))
+ break;
+ }
+
+ done_rx:
+ if (priv->bh_error)
+ break;
+ if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK)
+ goto rx;
+ if (tx)
+ goto tx;
+
+ done:
+ /* Re-enable device interrupts */
+ priv->hwbus_ops->lock(priv->hwbus_priv);
+ __cw1200_irq_enable(priv, 1);
+ priv->hwbus_ops->unlock(priv->hwbus_priv);
+ }
+
+ /* Explicitly disable device interrupts */
+ priv->hwbus_ops->lock(priv->hwbus_priv);
+ __cw1200_irq_enable(priv, 0);
+ priv->hwbus_ops->unlock(priv->hwbus_priv);
+
+ if (!term) {
+ pr_err("[BH] Fatal error, exiting.\n");
+ priv->bh_error = 1;
+ /* TODO: schedule_work(recovery) */
+ }
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff