From patchwork Wed Dec 20 14:57:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 13500203 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A0FD3C3DA6E for ; Wed, 20 Dec 2023 14:59:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=j2o2x2g8T21rtyzGwOsgFEETbej8g7MRS6u7VfuIMjc=; b=HGpq1CDwzizz3j v2o5SmQlcW1GknERtCGVarmLiYrjnSdc0vEmzdgxT0hG0W5pb8jDqGik1SrcGSg6OvjcvMC48Gkvg tC2F0+QWN75wJuTDTRy4bfTFXJthxb7Lxrla+eYpq3P+MbAHcIMzjLYH71r8BPfnrvtNJ01c8rqHI nQ6iTqTqL1XjHanuflQvoN3OlS7LXoCbDq3W0gvRuJLMVQxen93lO+p7sn9al1wArdpo9r8TaFk/e 2TXD4axxuTPDRtQ/FPL7aLXPQSRmV2a/k9Wl88iq3/nus9XfVybKhbWlGpwmZgDW/gFjrdNbWWHHw fG1D6VpKXd7L4qvByjRw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rFy2g-0009cR-1i; Wed, 20 Dec 2023 14:59:26 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rFy2Y-0009YG-39 for linux-arm-kernel@lists.infradead.org; Wed, 20 Dec 2023 14:59:21 +0000 Received: from pps.filterd (m0369457.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.22/8.17.1.22) with ESMTP id 3BKE2HmD025268; Wed, 20 Dec 2023 15:59:12 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= selector1; bh=x6nQQ71xtku6SiZZzFF5O30s9wsVUqCHS/O30UoRmzg=; b=f7 3ksnNaRy7Z4lT6orLLWkkndDsFgTqvKTEieeOOhJr8VJSnO7zboXsII2lDOphp17 45Gn2xDqRqbySut2TaoE2nbExxntKIRCH4tdpy1CneLc84PiSUiGG4i5zJsGp0l7 6qa9CUrsZ7Xn732fweNVmbvM7jP1ev+od1N7sBL7cZQZ3l/nbTSJB+2WGHt6zk5N hiRG/wGNlEgJFXB0Udqq6xSS4nly+nd0ePhWUEujKLZBaaa++JlyEP+LYlIyJ50Q x4++lATqmBf/32xVXIsD+B7292fEP5vdBFyZY0xZVe1QTczIZV1HOQg5SOsXXnj/ 90RsSqgiksUtmkETrJxg== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3v3q80u4kf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 20 Dec 2023 15:59:12 +0100 (CET) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id F0041100063; Wed, 20 Dec 2023 15:59:11 +0100 (CET) Received: from Webmail-eu.st.com (shfdag1node2.st.com [10.75.129.70]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id E493621B51F; Wed, 20 Dec 2023 15:59:11 +0100 (CET) Received: from localhost (10.201.20.59) by SHFDAG1NODE2.st.com (10.75.129.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Wed, 20 Dec 2023 15:59:11 +0100 From: Fabrice Gasnier To: CC: , , , , , , Subject: [PATCH v3 09/10] counter: stm32-timer-cnt: add support for overflow events Date: Wed, 20 Dec 2023 15:57:25 +0100 Message-ID: <20231220145726.640627-10-fabrice.gasnier@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231220145726.640627-1-fabrice.gasnier@foss.st.com> References: <20231220145726.640627-1-fabrice.gasnier@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.201.20.59] X-ClientProxiedBy: EQNCAS1NODE3.st.com (10.75.129.80) To SHFDAG1NODE2.st.com (10.75.129.70) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-20_09,2023-12-20_01,2023-05-22_02 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231220_065919_291415_EA899E17 X-CRM114-Status: GOOD ( 27.64 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add support overflow events. Also add the related validation and configuration routine. Register and enable interrupts to push events. STM32 Timers can have either 1 global interrupt, or 4 dedicated interrupt lines. Request only the necessary interrupt, e.g. either global interrupt that can report all event types, or update interrupt only for overflow event. Acked-by: Lee Jones Signed-off-by: Fabrice Gasnier --- Changes in v3: - patch split from: "counter: stm32-timer-cnt: add support for events", to focus on the overflow events only here. Move the capture event support to a separate patch. - simplify the patch, by removing diversity introduced by the number of possible channels. All channels are now exposed instead. Report an error when trying to access a channel that doesn't exist. Changes in v2: - fix warnings (kernel test robot) - fix a typo - add collected ack from Lee --- drivers/counter/stm32-timer-cnt.c | 132 +++++++++++++++++++++++++++++- include/linux/mfd/stm32-timers.h | 13 +++ 2 files changed, 144 insertions(+), 1 deletion(-) diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index b5dc4378fecf..d13e4c427965 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -8,6 +8,7 @@ * */ #include +#include #include #include #include @@ -44,6 +45,9 @@ struct stm32_timer_cnt { bool has_encoder; u32 idx; unsigned int nchannels; + unsigned int nr_irqs; + u32 *irq; + atomic_t nb_ovf; }; static const enum counter_function stm32_count_functions[] = { @@ -259,6 +263,29 @@ static int stm32_count_prescaler_write(struct counter_device *counter, return regmap_write(priv->regmap, TIM_PSC, psc); } +static int stm32_count_nb_ovf_read(struct counter_device *counter, + struct counter_count *count, u64 *val) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + + *val = atomic_read(&priv->nb_ovf); + + return 0; +} + +static int stm32_count_nb_ovf_write(struct counter_device *counter, + struct counter_count *count, u64 val) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + + if (val != (typeof(priv->nb_ovf.counter))val) + return -ERANGE; + + atomic_set(&priv->nb_ovf, val); + + return 0; +} + static struct counter_comp stm32_count_ext[] = { COUNTER_COMP_DIRECTION(stm32_count_direction_read), COUNTER_COMP_ENABLE(stm32_count_enable_read, stm32_count_enable_write), @@ -266,6 +293,7 @@ static struct counter_comp stm32_count_ext[] = { stm32_count_ceiling_write), COUNTER_COMP_COUNT_U64("prescaler", stm32_count_prescaler_read, stm32_count_prescaler_write), + COUNTER_COMP_COUNT_U64("num_overflows", stm32_count_nb_ovf_read, stm32_count_nb_ovf_write), }; static const enum counter_synapse_action stm32_clock_synapse_actions[] = { @@ -323,12 +351,57 @@ static int stm32_action_read(struct counter_device *counter, } } +static int stm32_count_events_configure(struct counter_device *counter) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + struct counter_event_node *event_node; + u32 val, dier = 0; + + list_for_each_entry(event_node, &counter->events_list, l) { + switch (event_node->event) { + case COUNTER_EVENT_OVERFLOW_UNDERFLOW: + /* first clear possibly latched UIF before enabling */ + regmap_read(priv->regmap, TIM_DIER, &val); + if (!(val & TIM_DIER_UIE)) + regmap_write(priv->regmap, TIM_SR, (u32)~TIM_SR_UIF); + dier |= TIM_DIER_UIE; + break; + default: + /* should never reach this path */ + return -EINVAL; + } + } + + regmap_write(priv->regmap, TIM_DIER, dier); + + return 0; +} + +static int stm32_count_watch_validate(struct counter_device *counter, + const struct counter_watch *watch) +{ + struct stm32_timer_cnt *const priv = counter_priv(counter); + + /* Interrupts are optional */ + if (!priv->nr_irqs) + return -EOPNOTSUPP; + + switch (watch->event) { + case COUNTER_EVENT_OVERFLOW_UNDERFLOW: + return 0; + default: + return -EINVAL; + } +} + static const struct counter_ops stm32_timer_cnt_ops = { .count_read = stm32_count_read, .count_write = stm32_count_write, .function_read = stm32_count_function_read, .function_write = stm32_count_function_write, .action_read = stm32_action_read, + .events_configure = stm32_count_events_configure, + .watch_validate = stm32_count_watch_validate, }; static int stm32_count_clk_get_freq(struct counter_device *counter, @@ -418,6 +491,35 @@ static struct counter_count stm32_counts = { .num_ext = ARRAY_SIZE(stm32_count_ext) }; +static irqreturn_t stm32_timer_cnt_isr(int irq, void *ptr) +{ + struct counter_device *counter = ptr; + struct stm32_timer_cnt *const priv = counter_priv(counter); + u32 clr = GENMASK(31, 0); /* SR flags can be cleared by writing 0 (wr 1 has no effect) */ + u32 sr, dier; + + regmap_read(priv->regmap, TIM_SR, &sr); + regmap_read(priv->regmap, TIM_DIER, &dier); + /* + * Some status bits in SR don't match with the enable bits in DIER. Only take care of + * the possibly enabled bits in DIER (that matches in between SR and DIER). + */ + dier &= TIM_DIER_UIE; + sr &= dier; + + if (sr & TIM_SR_UIF) { + atomic_inc(&priv->nb_ovf); + counter_push_event(counter, COUNTER_EVENT_OVERFLOW_UNDERFLOW, 0); + dev_dbg(counter->parent, "COUNTER_EVENT_OVERFLOW_UNDERFLOW\n"); + /* SR flags can be cleared by writing 0, only clear relevant flag */ + clr &= ~TIM_SR_UIF; + } + + regmap_write(priv->regmap, TIM_SR, clr); + + return IRQ_HANDLED; +}; + static void stm32_timer_cnt_detect_channels(struct platform_device *pdev, struct stm32_timer_cnt *priv) { @@ -480,7 +582,7 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct stm32_timer_cnt *priv; struct counter_device *counter; - int ret; + int i, ret; if (IS_ERR_OR_NULL(ddata)) return -EINVAL; @@ -494,6 +596,8 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) priv->regmap = ddata->regmap; priv->clk = ddata->clk; priv->max_arr = ddata->max_arr; + priv->nr_irqs = ddata->nr_irqs; + priv->irq = ddata->irq; ret = stm32_timer_cnt_probe_encoder(pdev, priv); if (ret) @@ -511,6 +615,32 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) platform_set_drvdata(pdev, priv); + /* STM32 Timers can have either 1 global, or 4 dedicated interrupts (optional) */ + if (priv->nr_irqs == 1) { + /* All events reported through the global interrupt */ + ret = devm_request_irq(&pdev->dev, priv->irq[0], stm32_timer_cnt_isr, + 0, dev_name(dev), counter); + if (ret) { + dev_err(dev, "Failed to request irq %d (err %d)\n", + priv->irq[i], ret); + return ret; + } + } else { + for (i = 0; i < priv->nr_irqs; i++) { + /* Only take care of update IRQ for overflow events */ + if (i != STM32_TIMERS_IRQ_UP) + continue; + + ret = devm_request_irq(&pdev->dev, priv->irq[i], stm32_timer_cnt_isr, + 0, dev_name(dev), counter); + if (ret) { + dev_err(dev, "Failed to request irq %d (err %d)\n", + priv->irq[i], ret); + return ret; + } + } + } + /* Reset input selector to its default input */ regmap_write(priv->regmap, TIM_TISEL, 0x0); diff --git a/include/linux/mfd/stm32-timers.h b/include/linux/mfd/stm32-timers.h index ca35af30745f..9eb17481b07f 100644 --- a/include/linux/mfd/stm32-timers.h +++ b/include/linux/mfd/stm32-timers.h @@ -41,6 +41,11 @@ #define TIM_SMCR_SMS (BIT(0) | BIT(1) | BIT(2)) /* Slave mode selection */ #define TIM_SMCR_TS (BIT(4) | BIT(5) | BIT(6)) /* Trigger selection */ #define TIM_DIER_UIE BIT(0) /* Update interrupt */ +#define TIM_DIER_CC1IE BIT(1) /* CC1 Interrupt Enable */ +#define TIM_DIER_CC2IE BIT(2) /* CC2 Interrupt Enable */ +#define TIM_DIER_CC3IE BIT(3) /* CC3 Interrupt Enable */ +#define TIM_DIER_CC4IE BIT(4) /* CC4 Interrupt Enable */ +#define TIM_DIER_CC_IE(x) BIT((x) + 1) /* CC1, CC2, CC3, CC4 interrupt enable */ #define TIM_DIER_UDE BIT(8) /* Update DMA request Enable */ #define TIM_DIER_CC1DE BIT(9) /* CC1 DMA request Enable */ #define TIM_DIER_CC2DE BIT(10) /* CC2 DMA request Enable */ @@ -49,6 +54,7 @@ #define TIM_DIER_COMDE BIT(13) /* COM DMA request Enable */ #define TIM_DIER_TDE BIT(14) /* Trigger DMA request Enable */ #define TIM_SR_UIF BIT(0) /* Update interrupt flag */ +#define TIM_SR_CC_IF(x) BIT((x) + 1) /* CC1, CC2, CC3, CC4 interrupt flag */ #define TIM_EGR_UG BIT(0) /* Update Generation */ #define TIM_CCMR_PE BIT(3) /* Channel Preload Enable */ #define TIM_CCMR_M1 (BIT(6) | BIT(5)) /* Channel PWM Mode 1 */ @@ -60,16 +66,23 @@ #define TIM_CCMR_CC1S_TI2 BIT(1) /* IC1/IC3 selects TI2/TI4 */ #define TIM_CCMR_CC2S_TI2 BIT(8) /* IC2/IC4 selects TI2/TI4 */ #define TIM_CCMR_CC2S_TI1 BIT(9) /* IC2/IC4 selects TI1/TI3 */ +#define TIM_CCMR_CC3S (BIT(0) | BIT(1)) /* Capture/compare 3 sel */ +#define TIM_CCMR_CC4S (BIT(8) | BIT(9)) /* Capture/compare 4 sel */ +#define TIM_CCMR_CC3S_TI3 BIT(0) /* IC3 selects TI3 */ +#define TIM_CCMR_CC4S_TI4 BIT(8) /* IC4 selects TI4 */ #define TIM_CCER_CC1E BIT(0) /* Capt/Comp 1 out Ena */ #define TIM_CCER_CC1P BIT(1) /* Capt/Comp 1 Polarity */ #define TIM_CCER_CC1NE BIT(2) /* Capt/Comp 1N out Ena */ #define TIM_CCER_CC1NP BIT(3) /* Capt/Comp 1N Polarity */ #define TIM_CCER_CC2E BIT(4) /* Capt/Comp 2 out Ena */ #define TIM_CCER_CC2P BIT(5) /* Capt/Comp 2 Polarity */ +#define TIM_CCER_CC2NP BIT(7) /* Capt/Comp 2N Polarity */ #define TIM_CCER_CC3E BIT(8) /* Capt/Comp 3 out Ena */ #define TIM_CCER_CC3P BIT(9) /* Capt/Comp 3 Polarity */ +#define TIM_CCER_CC3NP BIT(11) /* Capt/Comp 3N Polarity */ #define TIM_CCER_CC4E BIT(12) /* Capt/Comp 4 out Ena */ #define TIM_CCER_CC4P BIT(13) /* Capt/Comp 4 Polarity */ +#define TIM_CCER_CC4NP BIT(15) /* Capt/Comp 4N Polarity */ #define TIM_CCER_CCXE (BIT(0) | BIT(4) | BIT(8) | BIT(12)) #define TIM_BDTR_BKE(x) BIT(12 + (x) * 12) /* Break input enable */ #define TIM_BDTR_BKP(x) BIT(13 + (x) * 12) /* Break input polarity */