From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from trager.us (trager.us [52.5.81.116]) (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 7ED423C3C14; Mon, 31 Aug 2026 23:07:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.5.81.116 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788217647; cv=none; b=OBpvnKDcWY4cXT9RyYlXFFCCEm1vA44EpKpdzq+Axhr7l5bUtE1wZquu4DnM4p92Mi8x4J3NhVLfAiI6bE85UvZaHQozRLo4AnNQR2Q/QObiITKVc18Kc4Xb1DQS1EfH6iW4Es7b+xnW70CXi0TvSp7P002S8XbicG9a4WeOkGY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788217647; c=relaxed/simple; bh=ZKYbvUdQsXtqMDbl6xBIcD7cB8uHANDdOsGfTYUXct8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=r2SSQqZX/K/wzmgdL+7CXox4FFEKQu40dRZG3L0YGBLfrQxFZ4VpwQiAzGPLCLZjehAnpoxKPoKicHnabo2oHKOZIe+9X/PSFLyg3gUMzuUtYK4asWRSMgM5RKaSt62Ik0n2+556zbTW1OhZYzor0xaqQA6yRWWdiwOsl9DEjFU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=trager.us; spf=pass smtp.mailfrom=trager.us; arc=none smtp.client-ip=52.5.81.116 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=trager.us Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=trager.us Received: from c-73-254-161-40.hsd1.wa.comcast.net ([73.254.161.40] helo=[192.168.1.225]) by trager.us with esmtpsa (TLSv1.3:TLS_AES_128_GCM_SHA256:128) (Exim 4.92.3) (envelope-from ) id 1x1AMJ-0007sZ-6G; Mon, 31 Aug 2026 22:20:07 +0000 Message-ID: <948381d2-8ba7-458b-b729-d5398e0a8559@trager.us> Date: Mon, 31 Aug 2026 15:19:59 -0700 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 10/12] arm_mpam: add MPAM-Fb MSC firmware access support To: Andre Przywara , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Ben Horgan , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , Srivathsa L Rao , Ganapatrao Kulkarni , Trilok Soni , Srinivas Ramana , Niyas Sait , Ritwick Sharma , Gavin Shan , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260807105451.3728284-1-andre.przywara@arm.com> <20260807105451.3728284-11-andre.przywara@arm.com> Content-Language: en-US From: Lee Trager In-Reply-To: <20260807105451.3728284-11-andre.przywara@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 8/7/26 3:54 AM, Andre Przywara wrote: > + > +static int mpam_fb_send_request(struct mpam_msc *msc, u32 msc_id, > + u16 reg, u32 *result, int mpam_fb_command) > +{ > + unsigned int token = atomic_inc_return(&mpam_fb_token); > + struct acpi_pcct_ext_pcc_shared_memory __iomem *pcc_shmem; > + struct mpam_pcc_chan *pcc_chan; > + struct pcc_mbox_chan *chan; > + void __iomem *payload_ofs; > + int mpam_fb_err = 0; > + u32 status; > + int ret; > + > + pcc_chan = msc->pcc_chan; > + if (!pcc_chan) > + return -ENODEV; > + > + chan = pcc_chan->pcc_chan; > + > + /* prune token to fit into the 10 bits inside the command register */ > + token = FIELD_GET(MPAM_MSC_TOKEN_MASK, > + FIELD_PREP(MPAM_MSC_TOKEN_MASK, token)); > + > + mutex_lock(&pcc_chan->pcc_chan_lock); > + > + switch (mpam_fb_command) { > + case MPAM_PROTOCOL_VERSION_CMD: > + mpam_fb_build_version_message(token, chan->shmem); > + break; > + case MPAM_MSC_READ_CMD: > + mpam_fb_build_read_message(msc_id, reg, token, chan->shmem); > + break; > + case MPAM_MSC_WRITE_CMD: > + mpam_fb_build_write_message(msc_id, reg, *result, > + token, chan->shmem); > + break; > + default: > + dev_err(&msc->pdev->dev, "unsupported MPAM-Fb command %d\n", > + mpam_fb_command); > + ret = -EINVAL; > + goto out_err; > + } > + > + ret = mbox_send_message(chan->mchan, NULL); > + if (ret < 0) > + goto out_err; > + While testing this series when building arm64 allnoconfig with CONFIG_ARM4_MPAM=y I got a link failure: drivers/resctrl/mpam_fb.o: undefined reference to `mbox_send_message` Since the ACPI MPAM-Fb transport also reqiures PCC, wold it make sense for ARM64_MPAM_DRIVER to select both dependencies?     select MAILBOX     select PCC if ACPI Lee