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 D4DCB318EE6; Tue, 28 Apr 2026 20:17:04 +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=1777407426; cv=none; b=jlRvpjXPlV+9d+opgINfd3HmlvqQFX2QEh464dcsFCo6yvwz8KFDdyRGnxLvDYVaooNN0VKOtO4KSQ7XzXFqTe9FWedfy40WIwDugyZzVWdiAWAa9GJwGfz98+AerG4jBfsuILRPQMki7CNRUh4xerhM+/bvDT6rRW1hoAf/wAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777407426; c=relaxed/simple; bh=K7PZn6YSuIfgQkzQTbiCZFkzHkWlX1uWSHiLxI+Ap24=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Kb0QSguFfg+XFH9EmvUNjHAnVGaAXOyp9RX85B7TylzXuxLDPUgctX4QpnbdvGM/9GRtjnk/JOaZJJ9g4vUijnzDEqRHSiCXbOKP0j2GZTnIMPGXatRA4ZR8SyUyHwUyAXzSxxDBhXQhWH8tdOOETFW6lprJK0ySk/iPMeAoaGc= 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; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=oEwZIu3w; 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="oEwZIu3w" 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 E9D3A3296; Tue, 28 Apr 2026 13:16:58 -0700 (PDT) Received: from pluto.fritz.box (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6BE303F763; Tue, 28 Apr 2026 13:17:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1777407424; bh=K7PZn6YSuIfgQkzQTbiCZFkzHkWlX1uWSHiLxI+Ap24=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oEwZIu3w6S/Fe/vvdZdjMfnQ4oQ+JYSwW2y2KJHyi9vKTrIE0MMpyf1g5jXHKhO1Z x8LlifbPhYbE6pr8TGPstQIyx0NuUkMeoSjHC1Uh1+UfL9TGbb3xbqCK95XiVMukSX RiNn83gOJePq6gy9zrt9pKtHkLLI4aiF9tONwFdk= From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, arm-scmi@vger.kernel.org, linux-clk@vger.kernel.org, linux-renesas-soc@vger.kernel.org Cc: sudeep.holla@arm.com, philip.radford@arm.com, james.quinlan@broadcom.com, f.fainelli@gmail.com, vincent.guittot@linaro.org, etienne.carriere@foss.st.com, peng.fan@oss.nxp.com, michal.simek@amd.com, geert+renesas@glider.be, kuninori.morimoto.gx@renesas.com, marek.vasut+renesas@gmail.com, Cristian Marussi Subject: [PATCH v3 10/15] firmware: arm_scmi: Add bound iterators support Date: Tue, 28 Apr 2026 21:15:17 +0100 Message-ID: <20260428201522.903875-11-cristian.marussi@arm.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260428201522.903875-1-cristian.marussi@arm.com> References: <20260428201522.903875-1-cristian.marussi@arm.com> Precedence: bulk X-Mailing-List: linux-clk@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit SCMI core stack provides some common helpers to handle in a unified way multipart message replies: such iterator-helpers, when run, currently process by default the whole set of discovered resources. Introduce an alternative way to run the initialized iterator on a limited range of resources. Note that the subset of resources that can be chosen is anyway limited by the SCMI protocol specification, since you are only allowed to choose the start-index on a multi-part enumeration NOT the end-index, so that the effective number of returned items by a bound iterators depends really on platform side decisions. Suggested-by: Etienne Carriere Signed-off-by: Cristian Marussi --- v2 --> v3 - fixed typos in commit message --- drivers/firmware/arm_scmi/clock.c | 3 +- drivers/firmware/arm_scmi/driver.c | 58 +++++++++++++++++++-------- drivers/firmware/arm_scmi/protocols.h | 13 +++++- 3 files changed, 55 insertions(+), 19 deletions(-) diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c index d07cfef243fd..8ce889dfc87b 100644 --- a/drivers/firmware/arm_scmi/clock.c +++ b/drivers/firmware/arm_scmi/clock.c @@ -505,8 +505,7 @@ iter_clk_describe_process_response(const struct scmi_protocol_handle *ph, struct scmi_clk_ipriv *p = priv; const struct scmi_msg_resp_clock_describe_rates *r = response; - p->clkd->rates[st->desc_index + st->loop_idx] = - RATE_TO_U64(r->rate[st->loop_idx]); + p->clkd->rates[p->clkd->num_rates] = RATE_TO_U64(r->rate[st->loop_idx]); /* Count only effectively discovered rates */ p->clkd->num_rates++; diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 66cb64c8ed3d..cb4865fd8af2 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -1813,48 +1813,50 @@ static void *scmi_iterator_init(const struct scmi_protocol_handle *ph, return no_free_ptr(i); } -static int scmi_iterator_run(void *iter) +static int __scmi_iterator_run(void *iter, unsigned int *start, unsigned int *end) { int ret; struct scmi_iterator_ops *iops; const struct scmi_protocol_handle *ph; struct scmi_iterator_state *st; + struct scmi_iterator *i; if (!iter) return -EINVAL; - /* Take ownership of the iterator */ - struct scmi_iterator *i __free(kfree) = iter; - + i = iter; iops = i->ops; ph = i->ph; st = &i->state; + /* Reinitialize state for next run */ + st->num_returned = 0; + st->num_remaining = 0; + st->desc_index = start ? *start : 0; + do { iops->prepare_message(i->msg, st->desc_index, i->priv); ret = ph->xops->do_xfer(ph, i->t); if (ret) - break; + return ret; st->rx_len = i->t->rx.len; ret = iops->update_state(st, i->resp, i->priv); if (ret) - break; + return ret; if (st->num_returned > st->max_resources - st->desc_index) { dev_err(ph->dev, "No. of resources can't exceed %d\n", st->max_resources); - ret = -EINVAL; - break; + return -EINVAL; } - for (st->loop_idx = 0; !ret && st->loop_idx < st->num_returned; - st->loop_idx++) + for (st->loop_idx = 0; st->loop_idx < st->num_returned; st->loop_idx++) { ret = iops->process_response(ph, i->resp, st, i->priv); - - if (ret) - break; + if (ret) + return ret; + } st->desc_index += st->num_returned; ph->xops->reset_rx_to_maxsz(ph, i->t); @@ -1862,14 +1864,36 @@ static int scmi_iterator_run(void *iter) * check for both returned and remaining to avoid infinite * loop due to buggy firmware */ - } while (st->num_returned && st->num_remaining); + } while (st->num_returned && st->num_remaining && + (!end || (st->desc_index <= min(*end, st->max_resources - 1)))); - /* Finalize and destroy iterator */ - ph->xops->xfer_put(ph, i->t); + return 0; +} + +static void scmi_iterator_cleanup(void *iter) +{ + struct scmi_iterator *i = iter; + + i->ph->xops->xfer_put(i->ph, i->t); + kfree(i); +} + +static int scmi_iterator_run(void *iter) +{ + int ret; + + ret = __scmi_iterator_run(iter, NULL, NULL); + scmi_iterator_cleanup(iter); return ret; } +static int scmi_iterator_run_bound(void *iter, unsigned int *start, + unsigned int *end) +{ + return __scmi_iterator_run(iter, start, end); +} + struct scmi_msg_get_fc_info { __le32 domain; __le32 message_id; @@ -2048,6 +2072,8 @@ static const struct scmi_proto_helpers_ops helpers_ops = { .get_max_msg_size = scmi_common_get_max_msg_size, .iter_response_init = scmi_iterator_init, .iter_response_run = scmi_iterator_run, + .iter_response_run_bound = scmi_iterator_run_bound, + .iter_response_cleanup = scmi_iterator_cleanup, .protocol_msg_check = scmi_protocol_msg_check, .fastchannel_init = scmi_common_fastchannel_init, .fastchannel_db_ring = scmi_common_fastchannel_db_ring, diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h index f51245aca259..e2ef604c16ef 100644 --- a/drivers/firmware/arm_scmi/protocols.h +++ b/drivers/firmware/arm_scmi/protocols.h @@ -259,7 +259,15 @@ struct scmi_fc_info { * multi-part responses using the custom operations * provided in @ops. * @iter_response_run: A common helper to trigger the run of a previously - * initialized iterator. + * initialized iterator. Note that unbound iterators are + * automatically cleaned up. + * @iter_response_run_bound: A common helper to trigger the run of a previously + * initialized iterator, but only within the + * specified, optional, @start and @end resource + * indexes. Note that these bound-iterators need + * explicit cleanup via @iter_response_bound_cleanup. + * @iter_response_bound_cleanup: A common helper to finally release the iterator + * for bound iterators. * @protocol_msg_check: A common helper to check is a specific protocol message * is supported. * @fastchannel_init: A common helper used to initialize FC descriptors by @@ -276,6 +284,9 @@ struct scmi_proto_helpers_ops { unsigned int max_resources, u8 msg_id, size_t tx_size, void *priv); int (*iter_response_run)(void *iter); + int (*iter_response_run_bound)(void *iter, + unsigned int *start, unsigned int *end); + void (*iter_response_cleanup)(void *iter); int (*protocol_msg_check)(const struct scmi_protocol_handle *ph, u32 message_id, u32 *attributes); void (*fastchannel_init)(const struct scmi_protocol_handle *ph, -- 2.53.0