From patchwork Wed Apr 10 13:59:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Davis X-Patchwork-Id: 13624622 Received: from fllv0015.ext.ti.com (fllv0015.ext.ti.com [198.47.19.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B559D16E87F; Wed, 10 Apr 2024 13:59:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.19.141 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712757595; cv=none; b=aLf52zImYIZWPmtrB2hiAsDtKLQKWGJWKpp6jqmrcKPl6BjmYKOLjIFfdryC3Qx9OhT3bbPXNWzNKWS9u2fiJCfv0MkeZrQl3SK+KART+9VMNBp40L+VttKB70Kkl/XhMMjLQ3GMm68B1ZB6Z0nassFu+kvjHMVjAda35SxS2r8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712757595; c=relaxed/simple; bh=Zhl8BvhKtpPrlgnKaQ1BZAidyWWa+TJx1j06viQkwMA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=FmPgWGjXFz+gyXlu5o/ba/fcuElsfl7p6yOshdQKwJX1k/SNvRu7Z7pT3nsxqn3zyHj3WcZXshMOctT5WjVAVKjRuboCCmtTsXoPsN+nAJ5IArbY84jV09MQ7GipzHbSAivB8XMPpQOinbLSof5yxRGsbSR0yYokJC4Ksm/TQVQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=VVSoJy0t; arc=none smtp.client-ip=198.47.19.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="VVSoJy0t" Received: from lelv0265.itg.ti.com ([10.180.67.224]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 43ADxmKW024600; Wed, 10 Apr 2024 08:59:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1712757588; bh=Xva49Wa0r4m4+Jvqo/mGM4IoMNqfwpsfUf1TS+2klds=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=VVSoJy0t1OVs8jufe6Xh98t0pqk459g0othQE4aATnLBWcvtsEsQuwPkz48wlBmNO Q2xqJs4gQ75IMcpavZr5NpjZLzWrlZASqRVnl0CRmxLG0S4NMS6hv4XZmrw1K67u3m 596YIoMqDg8GN+wkaFw76XLnceqEGfv7+68BdD2Q= Received: from DFLE108.ent.ti.com (dfle108.ent.ti.com [10.64.6.29]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 43ADxmYH020094 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 10 Apr 2024 08:59:48 -0500 Received: from DFLE109.ent.ti.com (10.64.6.30) by DFLE108.ent.ti.com (10.64.6.29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Wed, 10 Apr 2024 08:59:48 -0500 Received: from lelvsmtp6.itg.ti.com (10.180.75.249) by DFLE109.ent.ti.com (10.64.6.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Wed, 10 Apr 2024 08:59:47 -0500 Received: from fllvsmtp8.itg.ti.com ([10.249.42.149]) by lelvsmtp6.itg.ti.com (8.15.2/8.15.2) with ESMTP id 43ADxhax067183; Wed, 10 Apr 2024 08:59:47 -0500 From: Andrew Davis To: Jassi Brar , Hari Nagalla , Nick Saulnier , Bjorn Andersson , Mathieu Poirier CC: , , Andrew Davis Subject: [PATCH v2 13/13] mailbox: omap: Remove kernel FIFO message queuing Date: Wed, 10 Apr 2024 08:59:42 -0500 Message-ID: <20240410135942.61667-14-afd@ti.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240410135942.61667-1-afd@ti.com> References: <20240410135942.61667-1-afd@ti.com> Precedence: bulk X-Mailing-List: linux-remoteproc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 The kernel FIFO queue has a couple issues. The biggest issue is that it causes extra latency in a path that can be used in real-time tasks, such as communication with real-time remote processors. The whole FIFO idea itself looks to be a leftover from before the unified mailbox framework. The current mailbox framework expects mbox_chan_received_data() to be called with data immediately as it arrives. Remove the FIFO and pass the messages to the mailbox framework directly as part of a threaded IRQ handler. Signed-off-by: Andrew Davis --- drivers/mailbox/Kconfig | 9 --- drivers/mailbox/omap-mailbox.c | 107 ++------------------------------- 2 files changed, 5 insertions(+), 111 deletions(-) diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index 42940108a1874..78e4c74fbe5c2 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -68,15 +68,6 @@ config OMAP2PLUS_MBOX OMAP2/3; or IPU, IVA HD and DSP in OMAP4/5. Say Y here if you want to use OMAP2+ Mailbox framework support. -config OMAP_MBOX_KFIFO_SIZE - int "Mailbox kfifo default buffer size (bytes)" - depends on OMAP2PLUS_MBOX - default 256 - help - Specify the default size of mailbox's kfifo buffers (bytes). - This can also be changed at runtime (via the mbox_kfifo_size - module parameter). - config ROCKCHIP_MBOX bool "Rockchip Soc Integrated Mailbox Support" depends on ARCH_ROCKCHIP || COMPILE_TEST diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c index c5d4083125856..46747559b438f 100644 --- a/drivers/mailbox/omap-mailbox.c +++ b/drivers/mailbox/omap-mailbox.c @@ -65,14 +65,6 @@ struct omap_mbox_fifo { u32 intr_bit; }; -struct omap_mbox_queue { - spinlock_t lock; - struct kfifo fifo; - struct work_struct work; - struct omap_mbox *mbox; - bool full; -}; - struct omap_mbox_match_data { u32 intr_type; }; @@ -90,7 +82,6 @@ struct omap_mbox_device { struct omap_mbox { const char *name; int irq; - struct omap_mbox_queue *rxq; struct omap_mbox_device *parent; struct omap_mbox_fifo tx_fifo; struct omap_mbox_fifo rx_fifo; @@ -99,10 +90,6 @@ struct omap_mbox { bool send_no_irq; }; -static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE; -module_param(mbox_kfifo_size, uint, S_IRUGO); -MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)"); - static inline unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs) { @@ -202,30 +189,6 @@ static void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq) mbox_write_reg(mbox->parent, bit, irqdisable); } -/* - * Message receiver(workqueue) - */ -static void mbox_rx_work(struct work_struct *work) -{ - struct omap_mbox_queue *mq = - container_of(work, struct omap_mbox_queue, work); - u32 msg; - int len; - - while (kfifo_len(&mq->fifo) >= sizeof(msg)) { - len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); - WARN_ON(len != sizeof(msg)); - - mbox_chan_received_data(mq->mbox->chan, (void *)(uintptr_t)msg); - spin_lock_irq(&mq->lock); - if (mq->full) { - mq->full = false; - omap_mbox_enable_irq(mq->mbox, IRQ_RX); - } - spin_unlock_irq(&mq->lock); - } -} - /* * Mailbox interrupt handler */ @@ -238,27 +201,15 @@ static void __mbox_tx_interrupt(struct omap_mbox *mbox) static void __mbox_rx_interrupt(struct omap_mbox *mbox) { - struct omap_mbox_queue *mq = mbox->rxq; u32 msg; - int len; while (!mbox_fifo_empty(mbox)) { - if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) { - omap_mbox_disable_irq(mbox, IRQ_RX); - mq->full = true; - goto nomem; - } - msg = mbox_fifo_read(mbox); - - len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg)); - WARN_ON(len != sizeof(msg)); + mbox_chan_received_data(mbox->chan, (void *)(uintptr_t)msg); } - /* no more messages in the fifo. clear IRQ source. */ + /* clear IRQ source. */ ack_mbox_irq(mbox, IRQ_RX); -nomem: - schedule_work(&mbox->rxq->work); } static irqreturn_t mbox_interrupt(int irq, void *p) @@ -274,57 +225,15 @@ static irqreturn_t mbox_interrupt(int irq, void *p) return IRQ_HANDLED; } -static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox, - void (*work)(struct work_struct *)) -{ - struct omap_mbox_queue *mq; - unsigned int size; - - if (!work) - return NULL; - - mq = kzalloc(sizeof(*mq), GFP_KERNEL); - if (!mq) - return NULL; - - spin_lock_init(&mq->lock); - - /* kfifo size sanity check: alignment and minimal size */ - size = ALIGN(mbox_kfifo_size, sizeof(u32)); - size = max_t(unsigned int, size, sizeof(u32)); - if (kfifo_alloc(&mq->fifo, size, GFP_KERNEL)) - goto error; - - INIT_WORK(&mq->work, work); - return mq; - -error: - kfree(mq); - return NULL; -} - -static void mbox_queue_free(struct omap_mbox_queue *q) -{ - kfifo_free(&q->fifo); - kfree(q); -} - static int omap_mbox_startup(struct omap_mbox *mbox) { int ret = 0; - struct omap_mbox_queue *mq; - - mq = mbox_queue_alloc(mbox, mbox_rx_work); - if (!mq) - return -ENOMEM; - mbox->rxq = mq; - mq->mbox = mbox; - ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED, - mbox->name, mbox); + ret = request_threaded_irq(mbox->irq, NULL, mbox_interrupt, + IRQF_ONESHOT, mbox->name, mbox); if (unlikely(ret)) { pr_err("failed to register mailbox interrupt:%d\n", ret); - goto fail_request_irq; + return ret; } if (mbox->send_no_irq) @@ -333,18 +242,12 @@ static int omap_mbox_startup(struct omap_mbox *mbox) omap_mbox_enable_irq(mbox, IRQ_RX); return 0; - -fail_request_irq: - mbox_queue_free(mbox->rxq); - return ret; } static void omap_mbox_fini(struct omap_mbox *mbox) { omap_mbox_disable_irq(mbox, IRQ_RX); free_irq(mbox->irq, mbox); - flush_work(&mbox->rxq->work); - mbox_queue_free(mbox->rxq); } static int omap_mbox_chan_startup(struct mbox_chan *chan)