From patchwork Fri Jan 15 11:05:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Coelho X-Patchwork-Id: 364321 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66424C433E0 for ; Fri, 15 Jan 2021 11:06:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E3D4206E4 for ; Fri, 15 Jan 2021 11:06:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726964AbhAOLGz (ORCPT ); Fri, 15 Jan 2021 06:06:55 -0500 Received: from paleale.coelho.fi ([176.9.41.70]:40314 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726534AbhAOLGz (ORCPT ); Fri, 15 Jan 2021 06:06:55 -0500 Received: from 91-156-6-193.elisa-laajakaista.fi ([91.156.6.193] helo=redipa.ger.corp.intel.com) by farmhouse.coelho.fi with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1l0Mvf-003hBK-LJ; Fri, 15 Jan 2021 13:06:08 +0200 From: Luca Coelho To: kvalo@codeaurora.org Cc: linux-wireless@vger.kernel.org Date: Fri, 15 Jan 2021 13:05:52 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210115110558.1248847-1-luca@coelho.fi> References: <20210115110558.1248847-1-luca@coelho.fi> MIME-Version: 1.0 Subject: [PATCH for v5.11 06/12] iwlwifi: fix the NMI flow for old devices Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Emmanuel Grumbach I noticed that the flow that triggers an NMI on the firmware for old devices (tested on 7265) doesn't work. Apparently, the firmware / device is still in low power when we write the register that triggers the NMI. We call the "grab_nic_access" function to make sure the device is awake but that wasn't enough. I played with this and noticed that if we wait 1 ms after the device reports it is awake before we write to the NMI register, the device always sees our write and the firmware gets properly asserted. Triggering an NMI to the firmware can be done with the debugfs hook: echo 1 > /sys/kernel/debug/iwlwifi/0000\:00\:03.0/iwlmvm/fw_nmi What happened before is that the firmware would just stall without running its NMI routine. Because of that the driver wouldn't get the "firmware crashed" interrupt. After a while the driver would notice that the firmware is not responding to some command and it would read the error data from the firmware, but this data is populated in the NMI service routine in the firmware which was not called. So in the logs it looked like: iwlwifi 0000:00:03.0: Error sending REPLY_ERROR: time out after 2000ms. iwlwifi 0000:00:03.0: Current CMD queue read_ptr 33 write_ptr 34 iwlwifi 0000:00:03.0: Loaded firmware version: 29.09bd31e1.0 7265D-29.ucode iwlwifi 0000:00:03.0: 0x00000000 | ADVANCED_SYSASSERT iwlwifi 0000:00:03.0: 0x00000000 | trm_hw_status0 iwlwifi 0000:00:03.0: 0x00000000 | trm_hw_status1 iwlwifi 0000:00:03.0: 0x00000000 | branchlink2 iwlwifi 0000:00:03.0: 0x00000000 | interruptlink1 iwlwifi 0000:00:03.0: 0x00000000 | interruptlink2 iwlwifi 0000:00:03.0: 0x00000000 | data1 iwlwifi 0000:00:03.0: 0x00000000 | data2 iwlwifi 0000:00:03.0: 0x00000000 | data3 iwlwifi 0000:00:03.0: 0x00000000 | beacon time iwlwifi 0000:00:03.0: 0x00000000 | tsf low ... With this fix, immediately after we trigger the NMI to the firmware, we get the expected: iwlwifi 0000:00:03.0: Microcode SW error detected. Restarting 0x2000000. iwlwifi 0000:00:03.0: Start IWL Error Log Dump: iwlwifi 0000:00:03.0: Status: 0x00000040, count: 6 iwlwifi 0000:00:03.0: Loaded firmware version: 29.09bd31e1.0 7265D-29.ucode iwlwifi 0000:00:03.0: 0x00000084 | NMI_INTERRUPT_UNKNOWN iwlwifi 0000:00:03.0: 0x000002F1 | trm_hw_status0 iwlwifi 0000:00:03.0: 0x00000000 | trm_hw_status1 iwlwifi 0000:00:03.0: 0x00043D6C | branchlink2 iwlwifi 0000:00:03.0: 0x0004AFD6 | interruptlink1 iwlwifi 0000:00:03.0: 0x000008C4 | interruptlink2 iwlwifi 0000:00:03.0: 0x00000000 | data1 iwlwifi 0000:00:03.0: 0x00000080 | data2 iwlwifi 0000:00:03.0: 0x07030000 | data3 iwlwifi 0000:00:03.0: 0x003FD4C3 | beacon time iwlwifi 0000:00:03.0: 0x00C22AC3 | tsf low iwlwifi 0000:00:03.0: 0x00000000 | tsf hi iwlwifi 0000:00:03.0: 0x00000000 | time gp1 iwlwifi 0000:00:03.0: 0x00C22AC3 | time gp2 iwlwifi 0000:00:03.0: 0x00000001 | uCode revision type iwlwifi 0000:00:03.0: 0x0000001D | uCode version major Notice the first line: "Microcode SW error detected:" which is printed in the driver's ISR, which means that the driver actually got an interrupt from the firmware saying that it crashed. And then we have the properly populated error data. Signed-off-by: Emmanuel Grumbach Signed-off-by: Luca Coelho --- drivers/net/wireless/intel/iwlwifi/iwl-io.c | 9 +++++---- drivers/net/wireless/intel/iwlwifi/iwl-io.h | 10 ++++++++-- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-io.c b/drivers/net/wireless/intel/iwlwifi/iwl-io.c index 2ac20d0a30eb..2b7ef1583e7f 100644 --- a/drivers/net/wireless/intel/iwlwifi/iwl-io.c +++ b/drivers/net/wireless/intel/iwlwifi/iwl-io.c @@ -150,16 +150,17 @@ u32 iwl_read_prph(struct iwl_trans *trans, u32 ofs) } IWL_EXPORT_SYMBOL(iwl_read_prph); -void iwl_write_prph(struct iwl_trans *trans, u32 ofs, u32 val) +void iwl_write_prph_delay(struct iwl_trans *trans, u32 ofs, u32 val, u32 delay_ms) { unsigned long flags; if (iwl_trans_grab_nic_access(trans, &flags)) { + mdelay(delay_ms); iwl_write_prph_no_grab(trans, ofs, val); iwl_trans_release_nic_access(trans, &flags); } } -IWL_EXPORT_SYMBOL(iwl_write_prph); +IWL_EXPORT_SYMBOL(iwl_write_prph_delay); int iwl_poll_prph_bit(struct iwl_trans *trans, u32 addr, u32 bits, u32 mask, int timeout) @@ -219,8 +220,8 @@ IWL_EXPORT_SYMBOL(iwl_clear_bits_prph); void iwl_force_nmi(struct iwl_trans *trans) { if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_9000) - iwl_write_prph(trans, DEVICE_SET_NMI_REG, - DEVICE_SET_NMI_VAL_DRV); + iwl_write_prph_delay(trans, DEVICE_SET_NMI_REG, + DEVICE_SET_NMI_VAL_DRV, 1); else if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_AX210) iwl_write_umac_prph(trans, UREG_NIC_SET_NMI_DRIVER, UREG_NIC_SET_NMI_DRIVER_NMI_FROM_DRIVER); diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-io.h b/drivers/net/wireless/intel/iwlwifi/iwl-io.h index 39bceee4e9e7..3c21c0e081f8 100644 --- a/drivers/net/wireless/intel/iwlwifi/iwl-io.h +++ b/drivers/net/wireless/intel/iwlwifi/iwl-io.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ /* - * Copyright (C) 2018-2019 Intel Corporation + * Copyright (C) 2018-2020 Intel Corporation */ #ifndef __iwl_io_h__ #define __iwl_io_h__ @@ -37,7 +37,13 @@ u32 iwl_read_prph_no_grab(struct iwl_trans *trans, u32 ofs); u32 iwl_read_prph(struct iwl_trans *trans, u32 ofs); void iwl_write_prph_no_grab(struct iwl_trans *trans, u32 ofs, u32 val); void iwl_write_prph64_no_grab(struct iwl_trans *trans, u64 ofs, u64 val); -void iwl_write_prph(struct iwl_trans *trans, u32 ofs, u32 val); +void iwl_write_prph_delay(struct iwl_trans *trans, u32 ofs, + u32 val, u32 delay_ms); +static inline void iwl_write_prph(struct iwl_trans *trans, u32 ofs, u32 val) +{ + iwl_write_prph_delay(trans, ofs, val, 0); +} + int iwl_poll_prph_bit(struct iwl_trans *trans, u32 addr, u32 bits, u32 mask, int timeout); void iwl_set_bits_prph(struct iwl_trans *trans, u32 ofs, u32 mask);