From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 672B9763E4; Mon, 3 Jun 2024 10:04:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717409080; cv=none; b=mgPT7AX94oXaYcGHogrCOyt7+9gLFh706QB1uTkdVMp0Vr86mRIlWGiMFYudK0wi0ScZsO0lcxPDg/H74D+ziawn+F0pOF88CUsqEmJ76sXMAMUwhMJ2DnGTcAKv9Y+/7x9VkbDSmSpqRbLYgET8mSMw+rNasi8JW5Tg5sqRT5Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717409080; c=relaxed/simple; bh=Yyjamq5fVatfQkYUI37mqc24+Gk56/U8JLXV7g9veNs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=LaU8cRJmkRYmbjdMfBuvvYasEBSl7DVpYKZstKhUa+erqLqFMFbsQ4qU+bocU7CFb3E/vZhhSC17XFByLh5Ljv6p2XDnkkPsqMmqYBG0VoTTXNRG36B046nURyzG+xEYg1dfPKOp70f2OB+jZURux2YvoUk1Tw6Ir06AqCUbigQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D12B71042; Mon, 3 Jun 2024 03:05:00 -0700 (PDT) Received: from [192.168.1.100] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6EA083F792; Mon, 3 Jun 2024 03:04:34 -0700 (PDT) Message-ID: Date: Mon, 3 Jun 2024 11:04:33 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/3] coresight: Add support to get preferred id for system trace sources To: Mao Jinlong Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Tingwei Zhang , Yuanfang Zhang , Tao Zhang , songchai , Suzuki K Poulose , Mike Leach , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alexander Shishkin References: <20240603094354.2348-1-quic_jinlmao@quicinc.com> <20240603094354.2348-3-quic_jinlmao@quicinc.com> Content-Language: en-US From: James Clark In-Reply-To: <20240603094354.2348-3-quic_jinlmao@quicinc.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 03/06/2024 10:43, Mao Jinlong wrote: > Dynamic trace id was introduced in coresight subsystem, so trace id is > allocated dynamically. However, some hardware ATB source has static trace > id and it cannot be changed via software programming. For such source, > it can call coresight_get_source_traceid to get the fixed trace id from > device node and pass id to coresight_trace_id_get_system_id to reserve > the id. > > Signed-off-by: Mao Jinlong > --- > .../hwtracing/coresight/coresight-platform.c | 26 +++++++++++++++ > drivers/hwtracing/coresight/coresight-stm.c | 2 +- > .../hwtracing/coresight/coresight-trace-id.c | 32 ++++++++++++------- > .../hwtracing/coresight/coresight-trace-id.h | 5 ++- > include/linux/coresight.h | 1 + > 5 files changed, 53 insertions(+), 13 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c > index 9d550f5697fa..8dd3cbd676b8 100644 > --- a/drivers/hwtracing/coresight/coresight-platform.c > +++ b/drivers/hwtracing/coresight/coresight-platform.c > @@ -183,6 +183,17 @@ static int of_coresight_get_cpu(struct device *dev) > return cpu; > } > > +/* > + * of_coresight_get_trace_id: Get the atid of a source device. > + * > + * Returns 0 on success. > + */ > +static int of_coresight_get_trace_id(struct device *dev, u32 *id) > +{ > + > + return of_property_read_u32(dev->of_node, "trace-id", id); > +} > + > /* > * of_coresight_parse_endpoint : Parse the given output endpoint @ep > * and fill the connection information in @pdata->out_conns > @@ -782,6 +793,12 @@ static inline int acpi_coresight_get_cpu(struct device *dev) > { > return -ENODEV; > } > + > +static int of_coresight_get_trace_id(struct device *dev, u32 *id) > +{ > + return -ENODEV; > +} > + > #endif > > int coresight_get_cpu(struct device *dev) > @@ -794,6 +811,15 @@ int coresight_get_cpu(struct device *dev) > } > EXPORT_SYMBOL_GPL(coresight_get_cpu); > > +int coresight_get_source_traceid(struct device *dev, u32 *id) > +{ > + if (!is_of_node(dev->fwnode)) > + return -EINVAL; > + > + return of_coresight_get_trace_id(dev, id); > +} > +EXPORT_SYMBOL_GPL(coresight_get_source_traceid); > + > struct coresight_platform_data * > coresight_get_platform_data(struct device *dev) > { > diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c > index e1c62820dfda..802f9e4ae570 100644 > --- a/drivers/hwtracing/coresight/coresight-stm.c > +++ b/drivers/hwtracing/coresight/coresight-stm.c > @@ -901,7 +901,7 @@ static int __stm_probe(struct device *dev, struct resource *res) > goto stm_unregister; > } > > - trace_id = coresight_trace_id_get_system_id(); > + trace_id = coresight_trace_id_get_system_id(0); I would #define 0 to "TRACE_ID_ANY" or something like that so it's obvious what it means. > if (trace_id < 0) { > ret = trace_id; > goto cs_unregister; > diff --git a/drivers/hwtracing/coresight/coresight-trace-id.c b/drivers/hwtracing/coresight/coresight-trace-id.c > index af5b4ef59cea..5c25c75a2f08 100644 > --- a/drivers/hwtracing/coresight/coresight-trace-id.c > +++ b/drivers/hwtracing/coresight/coresight-trace-id.c > @@ -75,20 +75,23 @@ static int coresight_trace_id_find_odd_id(struct coresight_trace_id_map *id_map) > * Allocate new ID and set in use > * > * if @preferred_id is a valid id then try to use that value if available. > + * if @only_preferred is true, if @preferred_id is used, return error EINVAL. if @only_preferred is true @preferred_id must be free, otherwise return error -EINVAL > * if @preferred_id is not valid and @prefer_odd_id is true, try for odd id. > * > * Otherwise allocate next available ID. > */ > static int coresight_trace_id_alloc_new_id(struct coresight_trace_id_map *id_map, > - int preferred_id, bool prefer_odd_id) > + int preferred_id, bool prefer_odd_id, bool only_preferred) > { > int id = 0; > > /* for backwards compatibility, cpu IDs may use preferred value */ > - if (IS_VALID_CS_TRACE_ID(preferred_id) && > - !test_bit(preferred_id, id_map->used_ids)) { > - id = preferred_id; > - goto trace_id_allocated; > + if (IS_VALID_CS_TRACE_ID(preferred_id)) { > + if (!test_bit(preferred_id, id_map->used_ids)) { > + id = preferred_id; > + goto trace_id_allocated; > + } else if (WARN(only_preferred, "Trace ID %d is used.\n", preferred_id)) > + return -EINVAL; > } else if (prefer_odd_id) { > /* may use odd ids to avoid preferred legacy cpu IDs */ > id = coresight_trace_id_find_odd_id(id_map); > @@ -175,7 +178,7 @@ static int coresight_trace_id_map_get_cpu_id(int cpu, struct coresight_trace_id_ > */ > id = coresight_trace_id_alloc_new_id(id_map, > CORESIGHT_LEGACY_CPU_TRACE_ID(cpu), > - false); > + false, false); > if (!IS_VALID_CS_TRACE_ID(id)) > goto get_cpu_id_out_unlock; > > @@ -222,14 +225,21 @@ static void coresight_trace_id_map_put_cpu_id(int cpu, struct coresight_trace_id > DUMP_ID_MAP(id_map); > } > > -static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *id_map) > +static int coresight_trace_id_map_get_system_id(struct coresight_trace_id_map *id_map, > + int preferred_id, bool only_preferred) Looks like "only_preferred" was left on here by mistake and it's not used. For this function preferred_id != 0 means the same. > { > unsigned long flags; > int id; > > spin_lock_irqsave(&id_map_lock, flags); > - /* prefer odd IDs for system components to avoid legacy CPU IDS */ > - id = coresight_trace_id_alloc_new_id(id_map, 0, true); > + > + if (preferred_id > 0) { > + /* use preferred id if it is available */ > + id = coresight_trace_id_alloc_new_id(id_map, preferred_id, false, true); > + } else { > + /* prefer odd IDs for system components to avoid legacy CPU IDS */ > + id = coresight_trace_id_alloc_new_id(id_map, 0, true, false); prefer_odd_id is different in each of these calls which I think is a mistake? You could do one function call to avoid that: only_preferred = preferred_id > 0 coresight_trace_id_alloc_new_id(id_map, preferred_id, true, only_preferred); > + } > spin_unlock_irqrestore(&id_map_lock, flags); > > DUMP_ID(id); > @@ -269,9 +279,9 @@ int coresight_trace_id_read_cpu_id(int cpu) > } > EXPORT_SYMBOL_GPL(coresight_trace_id_read_cpu_id); > > -int coresight_trace_id_get_system_id(void) > +int coresight_trace_id_get_system_id(int id) > { > - return coresight_trace_id_map_get_system_id(&id_map_default); > + return coresight_trace_id_map_get_system_id(&id_map_default, id, true); > } > EXPORT_SYMBOL_GPL(coresight_trace_id_get_system_id); > > diff --git a/drivers/hwtracing/coresight/coresight-trace-id.h b/drivers/hwtracing/coresight/coresight-trace-id.h > index 3797777d367e..9189a33c5857 100644 > --- a/drivers/hwtracing/coresight/coresight-trace-id.h > +++ b/drivers/hwtracing/coresight/coresight-trace-id.h > @@ -118,9 +118,12 @@ int coresight_trace_id_read_cpu_id(int cpu); > * > * Used to allocate IDs for system trace sources such as STM. > * > + * @id: Preferred id value. If id is 0, get a free id from id map. If id is greater 0 -> TRACE_ID_ANY > + * than 0, get a preferred id. > + * > * return: Trace ID or -EINVAL if allocation is impossible. > */ > -int coresight_trace_id_get_system_id(void); > +int coresight_trace_id_get_system_id(int id); > > /** > * Release an allocated system trace ID. > diff --git a/include/linux/coresight.h b/include/linux/coresight.h > index f09ace92176e..0599303be326 100644 > --- a/include/linux/coresight.h > +++ b/include/linux/coresight.h > @@ -643,6 +643,7 @@ void coresight_relaxed_write64(struct coresight_device *csdev, > void coresight_write64(struct coresight_device *csdev, u64 val, u32 offset); > > extern int coresight_get_cpu(struct device *dev); > +extern int coresight_get_source_traceid(struct device *dev, u32 *id); > > struct coresight_platform_data *coresight_get_platform_data(struct device *dev); > struct coresight_connection *