This has been extensively rewritten from ST-E's originally code, and is far more readable (and reliable). Signed-off-by: Solomon Peachy <pizza@xxxxxxxxxxxx> --- drivers/staging/cw1200/bh.c | 667 ++++++++++++++++++++++++++++++++++++++++++++ drivers/staging/cw1200/bh.h | 28 ++ 2 files changed, 695 insertions(+) create mode 100644 drivers/staging/cw1200/bh.c create mode 100644 drivers/staging/cw1200/bh.h diff --git a/drivers/staging/cw1200/bh.c b/drivers/staging/cw1200/bh.c new file mode 100644 index 0000000..cf7363c --- /dev/null +++ b/drivers/staging/cw1200/bh.c @@ -0,0 +1,667 @@ +/* + * Device handling thread implementation for mac80211 ST-Ericsson CW1200 drivers + * + * Copyright (c) 2010, ST-Ericsson + * Author: Dmitry Tarnyagin <dmitry.tarnyagin@xxxxxxxxxxxxxx> + * + * Based on: + * ST-Ericsson UMAC CW1200 driver, which is + * Copyright (c) 2010, ST-Ericsson + * Author: Ajitpal Singh <ajitpal.singh@xxxxxxxxxxxxxx> + * + * 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 "sbus.h" +#include "debug.h" +#include "fwio.h" + +#if defined(CONFIG_CW1200_BH_DEBUG) +#define bh_printk(...) printk(__VA_ARGS__) +#else +#define bh_printk(...) +#endif + +static int cw1200_bh(void *arg); + +/* TODO: Verify these numbers with WSM specification. */ +#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); + +#ifdef CONFIG_CW1200_POLL_IRQ +static void cw1200_irqpoll_timer_fn(unsigned long arg) +{ + struct cw1200_common *priv = (struct cw1200_common *) arg; + +#if 1 + if (atomic_add_return(1, &priv->bh_rx) == 1) +#else + atomic_add(1, &priv->bh_rx); +#endif + wake_up(&priv->bh_wq); +} +#endif + +int cw1200_register_bh(struct cw1200_common *priv) +{ + int err = 0; + struct sched_param param = { .sched_priority = 1 }; + bh_printk(KERN_DEBUG "[BH] register.\n"); + BUG_ON(priv->bh_thread); + 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->buf_id_tx = 0; + priv->buf_id_rx = 0; + init_waitqueue_head(&priv->bh_wq); + init_waitqueue_head(&priv->bh_evt_wq); + priv->bh_thread = kthread_create(&cw1200_bh, priv, "cw1200_bh"); + if (IS_ERR(priv->bh_thread)) { + err = PTR_ERR(priv->bh_thread); + priv->bh_thread = NULL; + } else { + WARN_ON(sched_setscheduler(priv->bh_thread, + SCHED_FIFO, ¶m)); +#ifdef HAS_PUT_TASK_STRUCT + get_task_struct(priv->bh_thread); +#endif + wake_up_process(priv->bh_thread); + } + +#ifdef CONFIG_CW1200_POLL_IRQ + init_timer(&priv->irqpoll_timer); + priv->irqpoll_timer.data = (unsigned long) priv; + priv->irqpoll_timer.function = cw1200_irqpoll_timer_fn; + mod_timer(&priv->irqpoll_timer, jiffies + HZ/100); +#endif + return err; +} + +void cw1200_unregister_bh(struct cw1200_common *priv) +{ + struct task_struct *thread = priv->bh_thread; + if (WARN_ON(!thread)) + return; + +#ifdef CONFIG_CW1200_POLL_IRQ + del_timer_sync(&priv->irqpoll_timer); +#endif + atomic_add(1, &priv->bh_term); + wake_up(&priv->bh_wq); + kthread_stop(thread); +#ifdef HAS_PUT_TASK_STRUCT + put_task_struct(thread); +#endif + priv->bh_thread = NULL; + bh_printk(KERN_DEBUG "[BH] unregistered.\n"); +} + +void cw1200_irq_handler(struct cw1200_common *priv) +{ + bh_printk(KERN_DEBUG "[BH] irq.\n"); + if (/* WARN_ON */(priv->bh_error)) + return; + +#ifndef CONFIG_CW1200_POLL_IRQ + /* Disable Interrupts */ + /* NOTE: sbus_ops->lock already held */ + if (priv->sbus_ops->irq_enable) { + priv->sbus_ops->irq_enable(priv->sbus_priv, 0); + } +#endif + +#if 1 + if (atomic_add_return(1, &priv->bh_rx) == 1) +#else + atomic_add(1, &priv->bh_rx); +#endif + wake_up(&priv->bh_wq); +} +EXPORT_SYMBOL_GPL(cw1200_irq_handler); + +void cw1200_bh_wakeup(struct cw1200_common *priv) +{ + bh_printk(KERN_DEBUG "[BH] wakeup.\n"); + if (WARN_ON(priv->bh_error)) + return; +#if 1 + if (atomic_add_return(1, &priv->bh_tx) == 1) +#else + atomic_add(1, &priv->bh_tx); +#endif + wake_up(&priv->bh_wq); +} + +int cw1200_bh_suspend(struct cw1200_common *priv) +{ + bh_printk(KERN_DEBUG "[BH] suspend.\n"); + if (WARN_ON(priv->bh_error)) + return 0; + + 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) +{ + bh_printk(KERN_DEBUG "[BH] resume.\n"); + if (WARN_ON(priv->bh_error)) + return 0; + + 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.numInpChBufs) + 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) + printk(KERN_ERR + "[BH] Failed to read control register.\n"); + } + + return ret; +} + +static int cw1200_device_wakeup(struct cw1200_common *priv) +{ + u16 ctrl_reg; + int ret; + + bh_printk(KERN_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) { + bh_printk(KERN_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) +{ + bh_printk(KERN_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))) { + printk(KERN_DEBUG "Invalid read len: %d (%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->sbus_ops->align_size( + priv->sbus_priv, read_len); + + /* Check if not exceeding CW1200 capabilities */ + if (WARN_ON_ONCE(alloc_len > EFFECTIVE_BUF_SIZE)) { + printk(KERN_DEBUG "Read aligned len: %d\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))) { + printk(KERN_ERR "rx blew up, len %d\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 defined(CONFIG_CW1200_WSM_DUMPS) + if (unlikely(priv->wsm_enable_wsm_dumps)) + print_hex_dump_bytes("<-- ", + DUMP_PREFIX_NONE, + data, min(wsm_len, wsm_dump_max)); +#endif /* CONFIG_CW1200_WSM_DUMPS */ + + wsm_id = __le16_to_cpu(wsm->id) & 0xFFF; + wsm_seq = (__le16_to_cpu(wsm->id) >> 13) & 7; + + skb_trim(skb_rx, wsm_len); + + if (unlikely(wsm_id == 0x0800)) { + wsm_handle_exception(priv, + &data[sizeof(*wsm)], + wsm_len - sizeof(*wsm)); + goto err; + } else if (unlikely(!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); + +#if 0 /* count is not implemented */ + if (ret > 1) + atomic_add(1, &priv->bh_tx); +#else + atomic_add(1, &priv->bh_tx); +#endif + + tx_len = priv->sbus_ops->align_size( + priv->sbus_priv, tx_len); + + /* Check if not exceeding CW1200 capabilities */ + if (WARN_ON_ONCE(tx_len > EFFECTIVE_BUF_SIZE)) { + printk(KERN_DEBUG "Write aligned len:" + " %d\n", tx_len); + } + + wsm->id &= __cpu_to_le16(~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))) { + printk(KERN_ERR "tx blew up, len %d\n", tx_len); + wsm_release_tx_buffer(priv, 1); + return -1; /* Error */ + } + +#if defined(CONFIG_CW1200_WSM_DUMPS) + if (unlikely(priv->wsm_enable_wsm_dumps)) + print_hex_dump_bytes("--> ", + DUMP_PREFIX_NONE, + data, + min(__le16_to_cpu(wsm->len), + wsm_dump_max)); +#endif /* CONFIG_CW1200_WSM_DUMPS */ + + 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; +#if defined(CONFIG_CW1200_WSM_DUMPS) + size_t wsm_dump_max = -1; +#endif + u32 dummy; + + for (;;) { + if (!priv->hw_bufs_used && + priv->powersave_enabled && + !priv->device_can_sleep) + status = 1 * HZ; + 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)); + +#if defined(CONFIG_CW1200_WSM_DUMPS_SHORT) + wsm_dump_max = priv->wsm_dump_max_size; +#endif /* CONFIG_CW1200_WSM_DUMPS_SHORT */ + + 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); + + /* Did an error occur? */ + if ((status < 0 && status != -ERESTARTSYS) || + term || priv->bh_error) { + break; + } + + if (priv->hw_bufs_used) { /* Outstanding tx in h/w */ + unsigned long timestamp = jiffies; + long timeout; + int pending = 0; + int i; + + if (!status && (!rx || !tx)) { + wiphy_warn(priv->hw->wiphy, "Missed interrupt? (%d 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); + + /* 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 tread 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 (!status) { + bh_printk(KERN_DEBUG "[BH] Device wakedown.\n"); + WARN_ON(cw1200_reg_write_16(priv, + ST90TDS_CONTROL_REG_ID, 0)); + priv->device_can_sleep = true; + goto done; + } else if (suspend) { + bh_printk(KERN_DEBUG "[BH] Device suspend.\n"); + if (priv->powersave_enabled) { + WARN_ON(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, + "%s: Failed to wait for resume: %ld.\n", + __func__, status); + break; + } + bh_printk(KERN_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; + } + + tx += pending_tx; + pending_tx = 0; + + if (rx) { + int ret; + if (WARN_ON(cw1200_bh_read_ctrl_reg( + priv, &ctrl_reg))) + break; + rx: + ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx); + if (ret < 0) + break; + ret = cw1200_bh_rx_helper(priv, &ctrl_reg, &tx); + if (ret < 0) + break; + } + + tx: + if (tx) { + int ret; + + BUG_ON(priv->hw_bufs_used > priv->wsm_caps.numInpChBufs); + tx_burst = priv->wsm_caps.numInpChBufs - priv->hw_bufs_used; + tx_allowed = tx_burst > 0; + + if (!tx_allowed) { + /* Ensure we go again */ + pending_tx = tx; + goto done_rx; + } + ret = cw1200_bh_tx_helper(priv, &pending_tx, &tx_burst); + if (ret < 0) + break; + if (ret > 0) + goto tx; + if (pending_tx) /* device is still asleep; we can't tx just yet */ + goto done_rx; + } + + done_rx: + if (ctrl_reg & ST90TDS_CONT_NEXT_LEN_MASK) + goto rx; + + done: +#ifdef CONFIG_CW1200_POLL_IRQ + mod_timer(&priv->irqpoll_timer, jiffies + HZ/100); +#else + /* Re-enable device interrupts */ + if (priv->sbus_ops->irq_enable) { + priv->sbus_ops->lock(priv->sbus_priv); + priv->sbus_ops->irq_enable(priv->sbus_priv, 1); + priv->sbus_ops->unlock(priv->sbus_priv); + } +#endif + } + +#ifdef CONFIG_CW1200_POLL_IRQ + del_timer_sync(&priv->irqpoll_timer); +#else + /* Re-enable device interrupts? */ + if (priv->sbus_ops->irq_enable) { + priv->sbus_ops->lock(priv->sbus_priv); + priv->sbus_ops->irq_enable(priv->sbus_priv, 1); + priv->sbus_ops->unlock(priv->sbus_priv); + } +#endif + + if (!term) { + printk(KERN_ERR "[BH] Fatal error, exiting.\n"); + priv->bh_error = 1; +#if defined(CONFIG_CW1200_USE_STE_EXTENSIONS) + ieee80211_driver_hang_notify(priv->vif, GFP_KERNEL); + cw1200_pm_stay_awake(&priv->pm_state, 3*HZ); +#endif + /* TODO: schedule_work(recovery) */ +#ifndef HAS_PUT_TASK_STRUCT + /* The only reason of having this stupid code here is + * that __put_task_struct is not exported by kernel. */ + for (;;) { + int status = wait_event_interruptible(priv->bh_wq, ({ + term = atomic_xchg(&priv->bh_term, 0); + (term); + })); + + if (status || term) + break; + } +#endif + } + return 0; +} diff --git a/drivers/staging/cw1200/bh.h b/drivers/staging/cw1200/bh.h new file mode 100644 index 0000000..fd8a8c5 --- /dev/null +++ b/drivers/staging/cw1200/bh.h @@ -0,0 +1,28 @@ +/* + * Device handling thread interface for mac80211 ST-Ericsson CW1200 drivers + * + * Copyright (c) 2010, ST-Ericsson + * Author: Dmitry Tarnyagin <dmitry.tarnyagin@xxxxxxxxxxxxxx> + * + * 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. + */ + +#ifndef CW1200_BH_H +#define CW1200_BH_H + +/* extern */ struct cw1200_common; + +int cw1200_register_bh(struct cw1200_common *priv); +void cw1200_unregister_bh(struct cw1200_common *priv); +void cw1200_irq_handler(struct cw1200_common *priv); +void cw1200_bh_wakeup(struct cw1200_common *priv); +int cw1200_bh_suspend(struct cw1200_common *priv); +int cw1200_bh_resume(struct cw1200_common *priv); +/* Must be called from BH thread. */ +void cw1200_enable_powersave(struct cw1200_common *priv, + bool enable); +int wsm_release_tx_buffer(struct cw1200_common *priv, int count); + +#endif /* CW1200_BH_H */ -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html