Return-path: Received: from mail-wi0-f171.google.com ([209.85.212.171]:34273 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752560AbbERJig (ORCPT ); Mon, 18 May 2015 05:38:36 -0400 Received: by wicmc15 with SMTP id mc15so84645686wic.1 for ; Mon, 18 May 2015 02:38:35 -0700 (PDT) From: Michal Kazior To: ath10k@lists.infradead.org Cc: linux-wireless@vger.kernel.org, Michal Kazior Subject: [PATCH v2 3/3] ath10k: enable pci soc powersaving Date: Mon, 18 May 2015 09:38:18 +0000 Message-Id: <1431941898-13591-4-git-send-email-michal.kazior@tieto.com> (sfid-20150518_113843_045022_1E898A00) In-Reply-To: <1431941898-13591-1-git-send-email-michal.kazior@tieto.com> References: <1431076388-24800-1-git-send-email-michal.kazior@tieto.com> <1431941898-13591-1-git-send-email-michal.kazior@tieto.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: By using SOC_WAKE register it is possible to bring down power consumption of QCA61X4 from 36mA to 16mA when associated and idle. Currently the sleep threshold/grace period is at a very conservative value of 60ms. Contrary to QCA61X4 the QCA988X firmware doesn't have Rx/beacon filtering available for client mode and SWBA events are used for beaconing in AP/IBSS so the SoC needs to be woken up at least every ~100ms in most cases. This means that QCA988X is at a disadvantage and the power consumption won't drop as much as for QCA61X4. Due to putting irq-safe spinlocks on every MMIO read/write it is expected this can cause a little performance regression on some systems. I haven't done any thorough measurements but some of my tests don't show any extreme degradation. The patch removes some explicit pci_wake calls that were added in 320e14b8db51aa ("ath10k: fix some pci wake/sleep issues"). This is safe because all MMIO accesses are now wrapped and the device is woken up automatically if necessary. Signed-off-by: Michal Kazior --- Notes: v2: * remove unnecessary hif.h include [Peter] drivers/net/wireless/ath/ath10k/debug.h | 1 + drivers/net/wireless/ath/ath10k/pci.c | 304 +++++++++++++++++++++++--------- drivers/net/wireless/ath/ath10k/pci.h | 91 +++++----- 3 files changed, 261 insertions(+), 135 deletions(-) diff --git a/drivers/net/wireless/ath/ath10k/debug.h b/drivers/net/wireless/ath/ath10k/debug.h index a12b8323f9f1..53bd6a19eab6 100644 --- a/drivers/net/wireless/ath/ath10k/debug.h +++ b/drivers/net/wireless/ath/ath10k/debug.h @@ -36,6 +36,7 @@ enum ath10k_debug_mask { ATH10K_DBG_REGULATORY = 0x00000800, ATH10K_DBG_TESTMODE = 0x00001000, ATH10K_DBG_WMI_PRINT = 0x00002000, + ATH10K_DBG_PCI_PS = 0x00004000, ATH10K_DBG_ANY = 0xffffffff, }; diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c index 8be07c653b2d..17a060e8efa2 100644 --- a/drivers/net/wireless/ath/ath10k/pci.c +++ b/drivers/net/wireless/ath/ath10k/pci.c @@ -330,6 +330,205 @@ static const struct service_to_pipe target_service_to_ce_map_wlan[] = { }, }; +static bool ath10k_pci_is_awake(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + u32 val = ioread32(ar_pci->mem + PCIE_LOCAL_BASE_ADDRESS + + RTC_STATE_ADDRESS); + + return RTC_STATE_V_GET(val) == RTC_STATE_V_ON; +} + +static void __ath10k_pci_wake(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + + lockdep_assert_held(&ar_pci->ps_lock); + + ath10k_dbg(ar, ATH10K_DBG_PCI_PS, "pci ps wake reg refcount %lu awake %d\n", + ar_pci->ps_wake_refcount, ar_pci->ps_awake); + + iowrite32(PCIE_SOC_WAKE_V_MASK, + ar_pci->mem + PCIE_LOCAL_BASE_ADDRESS + + PCIE_SOC_WAKE_ADDRESS); +} + +static void __ath10k_pci_sleep(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + + lockdep_assert_held(&ar_pci->ps_lock); + + ath10k_dbg(ar, ATH10K_DBG_PCI_PS, "pci ps sleep reg refcount %lu awake %d\n", + ar_pci->ps_wake_refcount, ar_pci->ps_awake); + + iowrite32(PCIE_SOC_WAKE_RESET, + ar_pci->mem + PCIE_LOCAL_BASE_ADDRESS + + PCIE_SOC_WAKE_ADDRESS); + ar_pci->ps_awake = false; +} + +static int ath10k_pci_wake_wait(struct ath10k *ar) +{ + int tot_delay = 0; + int curr_delay = 5; + + while (tot_delay < PCIE_WAKE_TIMEOUT) { + if (ath10k_pci_is_awake(ar)) + return 0; + + udelay(curr_delay); + tot_delay += curr_delay; + + if (curr_delay < 50) + curr_delay += 5; + } + + return -ETIMEDOUT; +} + +static int ath10k_pci_wake(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&ar_pci->ps_lock, flags); + + ath10k_dbg(ar, ATH10K_DBG_PCI_PS, "pci ps wake refcount %lu awake %d\n", + ar_pci->ps_wake_refcount, ar_pci->ps_awake); + + /* This function can be called very frequently. To avoid excessive + * CPU stalls for MMIO reads use a cache var to hold the device state. + */ + if (!ar_pci->ps_awake) { + __ath10k_pci_wake(ar); + + ret = ath10k_pci_wake_wait(ar); + if (ret == 0) + ar_pci->ps_awake = true; + } + + if (ret == 0) { + ar_pci->ps_wake_refcount++; + WARN_ON(ar_pci->ps_wake_refcount == 0); + } + + spin_unlock_irqrestore(&ar_pci->ps_lock, flags); + + return ret; +} + +static void ath10k_pci_sleep(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + unsigned long flags; + + spin_lock_irqsave(&ar_pci->ps_lock, flags); + + ath10k_dbg(ar, ATH10K_DBG_PCI_PS, "pci ps sleep refcount %lu awake %d\n", + ar_pci->ps_wake_refcount, ar_pci->ps_awake); + + if (WARN_ON(ar_pci->ps_wake_refcount == 0)) + goto skip; + + ar_pci->ps_wake_refcount--; + + mod_timer(&ar_pci->ps_timer, jiffies + + msecs_to_jiffies(ATH10K_PCI_SLEEP_GRACE_PERIOD_MSEC)); + +skip: + spin_unlock_irqrestore(&ar_pci->ps_lock, flags); +} + +static void ath10k_pci_ps_timer(unsigned long ptr) +{ + struct ath10k *ar = (void *)ptr; + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + unsigned long flags; + + spin_lock_irqsave(&ar_pci->ps_lock, flags); + + ath10k_dbg(ar, ATH10K_DBG_PCI_PS, "pci ps timer refcount %lu awake %d\n", + ar_pci->ps_wake_refcount, ar_pci->ps_awake); + + if (ar_pci->ps_wake_refcount > 0) + goto skip; + + __ath10k_pci_sleep(ar); + +skip: + spin_unlock_irqrestore(&ar_pci->ps_lock, flags); +} + +static void ath10k_pci_sleep_sync(struct ath10k *ar) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + unsigned long flags; + + del_timer_sync(&ar_pci->ps_timer); + + spin_lock_irqsave(&ar_pci->ps_lock, flags); + WARN_ON(ar_pci->ps_wake_refcount > 0); + __ath10k_pci_sleep(ar); + spin_unlock_irqrestore(&ar_pci->ps_lock, flags); +} + +void ath10k_pci_write32(struct ath10k *ar, u32 offset, u32 value) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + int ret; + + ret = ath10k_pci_wake(ar); + if (ret) { + ath10k_warn(ar, "failed to wake target for write32 of 0x%08x at 0x%08x: %d\n", + value, offset, ret); + return; + } + + iowrite32(value, ar_pci->mem + offset); + ath10k_pci_sleep(ar); +} + +u32 ath10k_pci_read32(struct ath10k *ar, u32 offset) +{ + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + u32 val; + int ret; + + ret = ath10k_pci_wake(ar); + if (ret) { + ath10k_warn(ar, "failed to wake target for read32 at 0x%08x: %d\n", + offset, ret); + return 0xffffffff; + } + + val = ioread32(ar_pci->mem + offset); + ath10k_pci_sleep(ar); + + return val; +} + +u32 ath10k_pci_soc_read32(struct ath10k *ar, u32 addr) +{ + return ath10k_pci_read32(ar, RTC_SOC_BASE_ADDRESS + addr); +} + +void ath10k_pci_soc_write32(struct ath10k *ar, u32 addr, u32 val) +{ + ath10k_pci_write32(ar, RTC_SOC_BASE_ADDRESS + addr, val); +} + +u32 ath10k_pci_reg_read32(struct ath10k *ar, u32 addr) +{ + return ath10k_pci_read32(ar, PCIE_LOCAL_BASE_ADDRESS + addr); +} + +void ath10k_pci_reg_write32(struct ath10k *ar, u32 addr, u32 val) +{ + ath10k_pci_write32(ar, PCIE_LOCAL_BASE_ADDRESS + addr, val); +} + static bool ath10k_pci_irq_pending(struct ath10k *ar) { u32 cause; @@ -793,60 +992,6 @@ static int ath10k_pci_diag_write32(struct ath10k *ar, u32 address, u32 value) return ath10k_pci_diag_write_mem(ar, address, &val, sizeof(val)); } -static bool ath10k_pci_is_awake(struct ath10k *ar) -{ - u32 val = ath10k_pci_reg_read32(ar, RTC_STATE_ADDRESS); - - return RTC_STATE_V_GET(val) == RTC_STATE_V_ON; -} - -static int ath10k_pci_wake_wait(struct ath10k *ar) -{ - int tot_delay = 0; - int curr_delay = 5; - - while (tot_delay < PCIE_WAKE_TIMEOUT) { - if (ath10k_pci_is_awake(ar)) - return 0; - - udelay(curr_delay); - tot_delay += curr_delay; - - if (curr_delay < 50) - curr_delay += 5; - } - - return -ETIMEDOUT; -} - -/* The rule is host is forbidden from accessing device registers while it's - * asleep. Currently ath10k_pci_wake() and ath10k_pci_sleep() calls aren't - * balanced and the device is kept awake all the time. This is intended for a - * simpler solution for the following problems: - * - * * device can enter sleep during s2ram without the host knowing, - * - * * irq handlers access registers which is a problem if other device asserts - * a shared irq line when ath10k is between hif_power_down() and - * hif_power_up(). - * - * FIXME: If power consumption is a concern (and there are *real* gains) then a - * refcounted wake/sleep needs to be implemented. - */ - -static int ath10k_pci_wake(struct ath10k *ar) -{ - ath10k_pci_reg_write32(ar, PCIE_SOC_WAKE_ADDRESS, - PCIE_SOC_WAKE_V_MASK); - return ath10k_pci_wake_wait(ar); -} - -static void ath10k_pci_sleep(struct ath10k *ar) -{ - ath10k_pci_reg_write32(ar, PCIE_SOC_WAKE_ADDRESS, - PCIE_SOC_WAKE_RESET); -} - /* Called by lower (CE) layer when a send to Target completes. */ static void ath10k_pci_ce_send_done(struct ath10k_ce_pipe *ce_state) { @@ -1348,6 +1493,9 @@ static void ath10k_pci_flush(struct ath10k *ar) static void ath10k_pci_hif_stop(struct ath10k *ar) { + struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); + unsigned long flags; + ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot hif stop\n"); /* Most likely the device has HTT Rx ring configured. The only way to @@ -1366,6 +1514,10 @@ static void ath10k_pci_hif_stop(struct ath10k *ar) ath10k_pci_irq_disable(ar); ath10k_pci_irq_sync(ar); ath10k_pci_flush(ar); + + spin_lock_irqsave(&ar_pci->ps_lock, flags); + WARN_ON(ar_pci->ps_wake_refcount > 0); + spin_unlock_irqrestore(&ar_pci->ps_lock, flags); } static int ath10k_pci_hif_exchange_bmi_msg(struct ath10k *ar, @@ -1990,12 +2142,6 @@ static int ath10k_pci_hif_power_up(struct ath10k *ar) ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot hif power up\n"); - ret = ath10k_pci_wake(ar); - if (ret) { - ath10k_err(ar, "failed to wake up target: %d\n", ret); - return ret; - } - pcie_capability_read_word(ar_pci->pdev, PCI_EXP_LNKCTL, &ar_pci->link_ctl); pcie_capability_write_word(ar_pci->pdev, PCI_EXP_LNKCTL, @@ -2047,7 +2193,6 @@ err_ce: ath10k_pci_ce_deinit(ar); err_sleep: - ath10k_pci_sleep(ar); return ret; } @@ -2064,7 +2209,12 @@ static void ath10k_pci_hif_power_down(struct ath10k *ar) static int ath10k_pci_hif_suspend(struct ath10k *ar) { - ath10k_pci_sleep(ar); + /* The grace timer can still be counting down and ar->ps_awake be true. + * It is known that the device may be asleep after resuming regardless + * of the SoC powersave state before suspending. Hence make sure the + * device is asleep before proceeding. + */ + ath10k_pci_sleep_sync(ar); return 0; } @@ -2074,13 +2224,6 @@ static int ath10k_pci_hif_resume(struct ath10k *ar) struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); struct pci_dev *pdev = ar_pci->pdev; u32 val; - int ret; - - ret = ath10k_pci_wake(ar); - if (ret) { - ath10k_err(ar, "failed to wake device up on resume: %d\n", ret); - return ret; - } /* Suspend/Resume resets the PCI configuration space, so we have to * re-disable the RETRY_TIMEOUT register (0x41) to keep PCI Tx retries @@ -2091,7 +2234,7 @@ static int ath10k_pci_hif_resume(struct ath10k *ar) if ((val & 0x0000ff00) != 0) pci_write_config_dword(pdev, 0x40, val & 0xffff00ff); - return ret; + return 0; } #endif @@ -2185,13 +2328,6 @@ static irqreturn_t ath10k_pci_interrupt_handler(int irq, void *arg) { struct ath10k *ar = arg; struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); - int ret; - - ret = ath10k_pci_wake(ar); - if (ret) { - ath10k_warn(ar, "failed to wake device up on irq: %d\n", ret); - return IRQ_NONE; - } if (ar_pci->num_msi_intrs == 0) { if (!ath10k_pci_irq_pending(ar)) @@ -2638,8 +2774,12 @@ static int ath10k_pci_probe(struct pci_dev *pdev, pdev->subsystem_vendor, pdev->subsystem_device); spin_lock_init(&ar_pci->ce_lock); + spin_lock_init(&ar_pci->ps_lock); + setup_timer(&ar_pci->rx_post_retry, ath10k_pci_rx_replenish_retry, (unsigned long)ar); + setup_timer(&ar_pci->ps_timer, ath10k_pci_ps_timer, + (unsigned long)ar); ret = ath10k_pci_claim(ar); if (ret) { @@ -2647,12 +2787,6 @@ static int ath10k_pci_probe(struct pci_dev *pdev, goto err_core_destroy; } - ret = ath10k_pci_wake(ar); - if (ret) { - ath10k_err(ar, "failed to wake up: %d\n", ret); - goto err_release; - } - ret = ath10k_pci_alloc_pipes(ar); if (ret) { ath10k_err(ar, "failed to allocate copy engine pipes: %d\n", @@ -2716,9 +2850,6 @@ err_free_pipes: ath10k_pci_free_pipes(ar); err_sleep: - ath10k_pci_sleep(ar); - -err_release: ath10k_pci_release(ar); err_core_destroy: @@ -2748,6 +2879,7 @@ static void ath10k_pci_remove(struct pci_dev *pdev) ath10k_pci_deinit_irq(ar); ath10k_pci_ce_deinit(ar); ath10k_pci_free_pipes(ar); + ath10k_pci_sleep_sync(ar); ath10k_pci_release(ar); ath10k_core_destroy(ar); } diff --git a/drivers/net/wireless/ath/ath10k/pci.h b/drivers/net/wireless/ath/ath10k/pci.h index ee2173d61257..d7696ddc03c4 100644 --- a/drivers/net/wireless/ath/ath10k/pci.h +++ b/drivers/net/wireless/ath/ath10k/pci.h @@ -191,6 +191,35 @@ struct ath10k_pci { * device bootup is executed and re-programmed later. */ u16 link_ctl; + + /* Protects ps_awake and ps_wake_refcount */ + spinlock_t ps_lock; + + /* The device has a special powersave-oriented register. When device is + * considered asleep it drains less power and driver is forbidden from + * accessing most MMIO registers. If host were to access them without + * waking up the device might scribble over host memory or return + * 0xdeadbeef readouts. + */ + unsigned long ps_wake_refcount; + + /* Waking up takes some time (up to 2ms in some cases) so it can be bad + * for latency. To mitigate this the device isn't immediately allowed + * to sleep after all references are undone - instead there's a grace + * period after which the powersave register is updated unless some + * activity to/from device happened in the meantime. + * + * Also see comments on ATH10K_PCI_SLEEP_GRACE_PERIOD_MSEC. + */ + struct timer_list ps_timer; + + /* MMIO registers are used to communicate with the device. With + * intensive traffic accessing powersave register would be a bit + * wasteful overhead and would needlessly stall CPU. It is far more + * efficient to rely on a variable in RAM and update it only upon + * powersave register state changes. + */ + bool ps_awake; }; static inline struct ath10k_pci *ath10k_pci_priv(struct ath10k *ar) @@ -215,61 +244,25 @@ static inline struct ath10k_pci *ath10k_pci_priv(struct ath10k *ar) * for this device; but that's not guaranteed. */ #define TARG_CPU_SPACE_TO_CE_SPACE(ar, pci_addr, addr) \ - (((ioread32((pci_addr)+(SOC_CORE_BASE_ADDRESS| \ + (((ath10k_pci_read32(ar, (SOC_CORE_BASE_ADDRESS | \ CORE_CTRL_ADDRESS)) & 0x7ff) << 21) | \ 0x100000 | ((addr) & 0xfffff)) /* Wait up to this many Ms for a Diagnostic Access CE operation to complete */ #define DIAG_ACCESS_CE_TIMEOUT_MS 10 -/* Target exposes its registers for direct access. However before host can - * access them it needs to make sure the target is awake (ath10k_pci_wake, - * ath10k_pci_wake_wait, ath10k_pci_is_awake). Once target is awake it won't go - * to sleep unless host tells it to (ath10k_pci_sleep). - * - * If host tries to access target registers without waking it up it can - * scribble over host memory. - * - * If target is asleep waking it up may take up to even 2ms. +void ath10k_pci_write32(struct ath10k *ar, u32 offset, u32 value); +void ath10k_pci_soc_write32(struct ath10k *ar, u32 addr, u32 val); +void ath10k_pci_reg_write32(struct ath10k *ar, u32 addr, u32 val); + +u32 ath10k_pci_read32(struct ath10k *ar, u32 offset); +u32 ath10k_pci_soc_read32(struct ath10k *ar, u32 addr); +u32 ath10k_pci_reg_read32(struct ath10k *ar, u32 addr); + +/* QCA6174 is known to have Tx/Rx issues when SOC_WAKE register is poked too + * frequently. To avoid this put SoC to sleep after a very conservative grace + * period. Adjust with great care. */ - -static inline void ath10k_pci_write32(struct ath10k *ar, u32 offset, - u32 value) -{ - struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); - - iowrite32(value, ar_pci->mem + offset); -} - -static inline u32 ath10k_pci_read32(struct ath10k *ar, u32 offset) -{ - struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); - - return ioread32(ar_pci->mem + offset); -} - -static inline u32 ath10k_pci_soc_read32(struct ath10k *ar, u32 addr) -{ - return ath10k_pci_read32(ar, RTC_SOC_BASE_ADDRESS + addr); -} - -static inline void ath10k_pci_soc_write32(struct ath10k *ar, u32 addr, u32 val) -{ - ath10k_pci_write32(ar, RTC_SOC_BASE_ADDRESS + addr, val); -} - -static inline u32 ath10k_pci_reg_read32(struct ath10k *ar, u32 addr) -{ - struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); - - return ioread32(ar_pci->mem + PCIE_LOCAL_BASE_ADDRESS + addr); -} - -static inline void ath10k_pci_reg_write32(struct ath10k *ar, u32 addr, u32 val) -{ - struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); - - iowrite32(val, ar_pci->mem + PCIE_LOCAL_BASE_ADDRESS + addr); -} +#define ATH10K_PCI_SLEEP_GRACE_PERIOD_MSEC 60 #endif /* _PCI_H_ */ -- 2.1.4