From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BA36F40B380; Thu, 9 Jul 2026 10:03:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783591424; cv=none; b=FECLXT7mB3EM2J0AE+1ikf1F1I3CNsAjTe64V2MC8IPF+bY6Gelg1XWIbkRob6ZBaHbxAS2iubqUoBHB92L9gnMYJNgLkTF/mxVCH5I12sEqvLTjyXl1Ypmx7cas8o/piK+vLaDeIFRYrzHx0Wcqv2WNVy8WAF2AIZWS9IkPcys= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783591424; c=relaxed/simple; bh=h731grFN6jIeLvs57QpZSFRZj5B14hzfQdgwJ6NTPkI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hk7EMi3vI0gHNp9gP7L0g146lzHhggzLHkXNsQBGGRJubAGYr2DrXgjeKi4glAVDoZJ/edSyk5LTpl/cq3MLN1GwTZQyiIy8mS/eoicmAVwrfDYfYsyhjTwGYoVBFZ/DHjPfq4QNj3m5T1L1QAcXRUHP91mERhjIISlSwTL+6y4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=on8J6TC7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="on8J6TC7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1650B1F000E9; Thu, 9 Jul 2026 10:03:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783591423; bh=X8up9YknUH72DuNpBb/fmTdhl5fIKBCdLdnO90H4hqE=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=on8J6TC7rSi/uQfDu+aIqT4su/uxGM4PLRIHnX7nxWGIdUzXhwcZIopti+Kcv7djP 2ANk38puMfrlnaFW89fzkZWWx1soSqy6BaKnHA4IGS9ACPkeogpMeJ+OE5YQta9vZr gb0uOxMN6dVW46PVhPtpTwtSrzufB2E7WYlLYvgjSnvgP/XioqZYQHhC9nHzw3p1Wz 8riTw9MvVrfIC++2WkGCqK2vWWXqzI1QmA2ZIxcMQEKinNX8+qjIsnISXMTcKljr3i 0RrodIUXI8vZtu1ZepcZ52lfixGPpVXNMvb6OZeNcUb5T4x9zUOEb980pomfrJpdTR Khz4uLqXRF5ig== Message-ID: Date: Thu, 9 Jul 2026 12:03:36 +0200 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] firmware: samsung: acpm: add fire-and-forget xfer support To: Alexey Klimov , Tudor Ambarus , Sam Protsenko , Peter Griffin , Alim Akhtar , "Rafael J. Wysocki" , Viresh Kumar Cc: Sudeep Holla , linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org References: <20260612-acpm-fast-xfer-v1-0-1aa6cd2268ba@linaro.org> <20260612-acpm-fast-xfer-v1-1-1aa6cd2268ba@linaro.org> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGPBBMBCgA5AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJp2mE8AAoJEBuTQ307QWKbeaIP /ihHTkTW4KsN/DQ945JJbyu5tI0J80Wue7QyyLPglyKfhgb5cLLNPpOC8cCIJsc7+W3i2P38 s2c1cOH6CYGE7E9ur3Vfme8NW2S2I/Z8VC7bZnzyS23wT17LrsdS/qCpx4o8U+pt/xdXDKph EGRYrIEmMpUWvyYzyYKGIe25FtaayIIKpq8eZYyFcp2f/sG5IkOW5uZzHPMPdcm87jU7fyuQ rAU2vx9r+ulUfQ/q9Z2roC/ode3l7t2pN7BCBCsUDp6JCrUyZrtT1e7EbA0ZRP3aOBNk2P2E DQOgJGjGdO5Yx2Y9LFtltu6JbsBJHi1syGRX3AtQYOMc4Y1WGoeZJmMlvKj2ZqqXNkcWi2DS IQEWB0uW6CqFsBBIMGDa+6OzdaVO/uAVXWDWml02Men3CILdI1MbVjoh8ECqYUY7OQ+JJvNN vnliuq5WM3Ghd3jg/LZZrxXjdIginRHFQCjIJYLKpLZWm1/iDFedcfzqRNYmTtqscdCNHW41 oT3Z7BmO9xwdjuwBS6nmS6JJwkbf5Ot2QR4pB/DRU7ZwjT1qHe+9r9gF32wXVQatHNGK/VVu sfwOnkdxCWkp/qb2gdQRmZh+SedStWshigH6sNfuHBloF/q+hjMRc8b2m326OZdrbSHwY1Sz vti8Hn7n8NjdHO9LKB7BIdjkA9DA5WsqOuVCzsFNBFVDXDQBEADNkrQYSREUL4D3Gws46JEo Z9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLueMNsWLJBv BaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6eiOMheesVS 5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wAGldWsRxb f3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA6z6lBZn0 WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9YegxWKvX XHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt91pFzBSO IpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gUBLHFTg2h YnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/JoFzZ4B0 p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu4vXVFBYI GmpyNPYzRm0QPwARAQABwsF2BBgBCgAgAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtBYpsFAmna YUkACgkQG5NDfTtBYptX+BAApg32CkxwNucNEi8WfWA8oKkW0y8YDuY6ORMo9FWNGiT/OTy0 vyJrLocrpn86zwfjVp+eCrssPYh8eqJfnWqmYv6ACQtHPYzPZQ3mSo8H97Z01oUxITzCxpXm ZkLgPIqtDPcC2E3dPM/fVxcyowM8XsaMA9wcsaUYrta8toOq2b9tKcjleKMfMrm0gQ9u7wUc QbLkwj6TCLOwucb07GXzLTNF9PZmaDUpKAZjMjmrW+le+SFvQbhamx0rxLWPR0NWntXpbCn+ +ACch03p/JyTBVktxFsFyCt7pTPE1kEaeuXBTe/a2D9iQvRxRW19LvuO2e59/u1wYUiH/orz wbIC2S4dBsPAPihL3ztOU1yE86GPyQtSE0kU+/7snnLt4QGi6PChf3t5gnNjAzjUUovO8rgI c+5yN5heq5loYHgK6OQ9OlHzsPHO9e9MOQcKlFycs1pyijFGzDwdNUm/SchK8iWT2QApTx4A K9bCVaboTA2T77QYkRcRJYSsO1alGX0ome/hMLD1daXlkrNUp1HWa3K4iytLRXjCSIorWiGs n+q3krnpXu3TFkA8qtOFZMdnIiFuiq1yLT8hptsV5xh1TA2nsVvSYiaCr3q4s4BKjS/KrLDb qoxzw8ISjdUp4pA85vb6YLCmb39NgidD+7PmAr65lBNveIFynTgsja1rRQ4= In-Reply-To: <20260612-acpm-fast-xfer-v1-1-1aa6cd2268ba@linaro.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/06/2026 06:34, Alexey Klimov wrote: > > +int acpm_dvfs_set_rate_fast(struct acpm_handle *handle, > + unsigned int acpm_chan_id, unsigned int clk_id, > + unsigned long rate) > +{ > + struct acpm_xfer xfer = {0}; > + u32 cmd[4]; > + > + acpm_dvfs_init_set_rate_cmd(cmd, clk_id, rate); > + acpm_set_xfer(&xfer, cmd, ARRAY_SIZE(cmd), acpm_chan_id, false); > + > + return acpm_do_xfer_fast(handle, &xfer); > +} > + > + Just one blank line > static void acpm_dvfs_init_get_rate_cmd(u32 cmd[4], unsigned int clk_id) > { > cmd[0] = FIELD_PREP(ACPM_DVFS_ID, clk_id); > diff --git a/drivers/firmware/samsung/exynos-acpm-dvfs.h b/drivers/firmware/samsung/exynos-acpm-dvfs.h > index b37b15426102..107d9aa27690 100644 > --- a/drivers/firmware/samsung/exynos-acpm-dvfs.h > +++ b/drivers/firmware/samsung/exynos-acpm-dvfs.h > @@ -14,6 +14,9 @@ struct acpm_handle; > int acpm_dvfs_set_rate(struct acpm_handle *handle, > unsigned int acpm_chan_id, unsigned int id, > unsigned long rate); > +int acpm_dvfs_set_rate_fast(struct acpm_handle *handle, > + unsigned int acpm_chan_id, unsigned int id, > + unsigned long rate); > unsigned long acpm_dvfs_get_rate(struct acpm_handle *handle, > unsigned int acpm_chan_id, ... > + do { > + val = readl(base + mlen * i); > + rx_seqnum = FIELD_GET(ACPM_PROTOCOL_SEQNUM, val); > + > + if (rx_seqnum) { > + seqnum = rx_seqnum - 1; > + rx_data = &achan->rx_data[seqnum]; > + > + if (rx_data->rxcnt) > + __ioread32_copy(rx_data->cmd, base + mlen * i, rx_data->rxcnt); > + > + /* Signal the waiting thread (if any). If it hasn't started Please use Linux style comments. > + * spinning yet, it will see this instantly when it does. */ > + smp_store_release(&rx_data->completed, true); > + > + /* Only free the sequence number if it belongs to an > + * async request. Senders who use regular acpm_do_xfer() > + * will free their own sequence numbers in > + * acpm_dequeue_by_polling(). > + */ > + if (rx_data->is_async) > + clear_bit_unlock(seqnum, achan->bitmap_seqnum); > + } > + > + i = (i + 1) % achan->qlen; > + } while (i != rx_front); > + > + writel(rx_front, achan->rx.rear); > + > + spin_unlock(&achan->rx_lock); > +} > + > /** > * acpm_dequeue_by_polling() - RX dequeue by polling. > * @achan: ACPM channel info. > @@ -388,15 +446,15 @@ static int acpm_wait_for_queue_slots(struct acpm_chan *achan, u32 next_tx_front) > } > ... > + > /** > * acpm_do_xfer() - do one transfer. > * @handle: pointer to the acpm handle. > @@ -485,7 +606,7 @@ int acpm_do_xfer(struct acpm_handle *handle, const struct acpm_xfer *xfer) > msg.chan_id = xfer->acpm_chan_id; > msg.chan_type = EXYNOS_MBOX_CHAN_TYPE_DOORBELL; > > - scoped_guard(mutex, &achan->tx_lock) { > + scoped_guard(spinlock, &achan->tx_lock) { This blind replacement just feels completely wrong. Not only you made huge part of code non-sleepable but actually put spinlock over readl_poll_timeout with 2*500 ms timeout. > tx_front = readl(achan->tx.front); > idx = (tx_front + 1) % achan->qlen; > > @@ -654,8 +775,8 @@ static int acpm_channels_init(struct acpm_info *acpm) > if (ret) > return ret; > Best regards, Krzysztof