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 8FB5A2DAFA9; Fri, 8 May 2026 10:21:30 +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=1778235692; cv=none; b=gQjXCx0wk9bAMmySHPh3vdWbC3eCmmASsd1g8zUNwmj62RPtdv5F9bEwIcrziAczX14JcJRGL7Sj5wunpjgRXl4wI/urbTQrPu6+UpTaovQCryvl8b3U6EmdFQJPXbOFOyed+iR1fui1+4jrHwn6TRIhgHr8xHs6yj56CzeLVJM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778235692; c=relaxed/simple; bh=oPupvqWJ0GwO+YvPgf2njzvz2yfMTQZ//f9TQ35sTbA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=CO7RomeuuW77od1aE/OEtA/EIkm5y/KXthjJ1VWtP/b2g835uDiAfEPQ0LtDUhzO/ZnxvUOaXnSiK2G4CQRaw3syQJQg1OovpVMnlsFI//ETH1C5+ye9MiE7XfBJIMDRNR9kApaX5L8CbWsJZRARIgle/2Qgajbf2mHjT9diz3k= 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=YcRoMlN7; 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="YcRoMlN7" 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 9341A1BCA; Fri, 8 May 2026 03:21:18 -0700 (PDT) Received: from [10.1.196.46] (e134344.arm.com [10.1.196.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 418F33F763; Fri, 8 May 2026 03:21:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778235683; bh=oPupvqWJ0GwO+YvPgf2njzvz2yfMTQZ//f9TQ35sTbA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=YcRoMlN79/DrdWDeyLFfoAkfFsj1WHMMbEWwzocwegPHBw9FyPKM32HFo6+gelmoO 76O60oA8qy7ANB5qf53lmolVVelSPwCChegFwYpiKWA9em36eaqXzTgPy7wo5Ek08J ya5YkCQzl4t9z26+WDqymc3oKqqib0FnB5HGv4O0= Message-ID: Date: Fri, 8 May 2026 11:21:20 +0100 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Thunderbird Daily Subject: Re: [PATCH 1/5] arm_mpam: Parse the rest of the ACPI table To: Andre Przywara , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260429141339.3171205-1-andre.przywara@arm.com> <20260429141339.3171205-2-andre.przywara@arm.com> Content-Language: en-US From: Ben Horgan In-Reply-To: <20260429141339.3171205-2-andre.przywara@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Andre, On 4/29/26 15:13, Andre Przywara wrote: > From: James Morse > > The MPAM ACPI table lists the MPAM MSCs and indicates which resources > in the system they control. Not everything this table can describe is > supported by resctrl, e.g. memory-side-caches. > > Add the additional table parsing to avoid reporting these as 'unknown' > to the MPAM driver. This allows class+component hierarchys to be built. > > Until resctrl has support for any of these resources, users would be > in-kernel managers of a resource/PARTID or perf to query bandwidth > counters on a resource resctrl is unaware of. Does this patch give us anything needed for MPAM-Fb? It seems to just add parsing for things we don't support in the MPAM driver. Thanks, Ben > > Signed-off-by: James Morse > Signed-off-by: Andre Przywara > --- > drivers/acpi/arm64/mpam.c | 91 +++++++++++++++++++++++++++++++++++++-- > 1 file changed, 88 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/arm64/mpam.c b/drivers/acpi/arm64/mpam.c > index 84963a20c3e7..99c2bdbb3314 100644 > --- a/drivers/acpi/arm64/mpam.c > +++ b/drivers/acpi/arm64/mpam.c > @@ -95,17 +95,51 @@ static void acpi_mpam_parse_irqs(struct platform_device *pdev, > res[(*res_idx)++] = DEFINE_RES_IRQ_NAMED(irq, "error"); > } > > -static int acpi_mpam_parse_resource(struct mpam_msc *msc, > +#define UUID_MPAM_INTERCONNECT_TABLE "fe2bd645-033b-49e6-9479-2e0b8b21d1cd" > + > +struct acpi_mpam_interconnect_descriptor_table { > + u8 type_uuid[16]; > + u32 num_descriptors; > +}; > + > +struct acpi_mpam_interconnect_descriptor { > + u32 source_id; > + u32 destination_id; > + u8 link_type; > + u8 reserved[3]; > +}; > + > +static int acpi_mpam_parse_resource(struct acpi_mpam_msc_node *tbl_msc, > + struct mpam_msc *msc, > struct acpi_mpam_resource_node *res) > { > + struct acpi_mpam_interconnect_descriptor_table *tbl_int_tbl; > + struct acpi_mpam_interconnect_descriptor *tbl_int; > + guid_t int_tbl_uuid, spec_uuid; > int level, nid; > u32 cache_id; > + off_t offset; > > + /* > + * Class IDs are somewhat arbitrary, but need to be co-ordinated. > + * 0-N are caches, > + * 64, 65: Interconnect, but ideally these would appear between the > + * classes the controls are adjacent to. > + * 128: SMMU, > + * 192-192+level: Memory Side Caches, nothing checks that N is a > + * small number. > + * 255: Memory Controllers > + * > + * ACPI devices would need a class id allocated based on the _HID. > + * > + * Classes that the mpam driver can't currently plumb into resctrl > + * are registered as UNKNOWN. > + */ > switch (res->locator_type) { > case ACPI_MPAM_LOCATION_TYPE_PROCESSOR_CACHE: > cache_id = res->locator.cache_locator.cache_reference; > level = find_acpi_cache_level_from_id(cache_id); > - if (level <= 0) { > + if (level <= 0 || level >= 64) { > pr_err_once("Bad level (%d) for cache with id %u\n", level, cache_id); > return -EINVAL; > } > @@ -120,6 +154,57 @@ static int acpi_mpam_parse_resource(struct mpam_msc *msc, > } > return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_MEMORY, > MPAM_CLASS_ID_DEFAULT, nid); > + case ACPI_MPAM_LOCATION_TYPE_SMMU: > + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_UNKNOWN, > + 128, res->locator.smmu_locator.smmu_interface); > + case ACPI_MPAM_LOCATION_TYPE_MEMORY_CACHE: > + cache_id = res->locator.mem_cache_locator.reference; > + level = res->locator.mem_cache_locator.level; > + if (192 + level >= 255) { > + pr_err_once("Bad level for memory side cache with reference %u\n", > + cache_id); > + return -EINVAL; > + } > + > + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_CACHE, > + 192 + level, cache_id); > + > + case ACPI_MPAM_LOCATION_TYPE_INTERCONNECT: > + /* Find the descriptor table, and check it lands in the parent msc */ > + offset = res->locator.interconnect_ifc_locator.inter_connect_desc_tbl_off; > + if (offset >= tbl_msc->length) { > + pr_err_once("Bad offset for interconnect descriptor on msc %u\n", > + tbl_msc->identifier); > + return -EINVAL; > + } > + tbl_int_tbl = ACPI_ADD_PTR(struct acpi_mpam_interconnect_descriptor_table, > + tbl_msc, offset); > + guid_parse(UUID_MPAM_INTERCONNECT_TABLE, &spec_uuid); > + import_guid(&int_tbl_uuid, tbl_int_tbl->type_uuid); > + if (guid_equal(&spec_uuid, &int_tbl_uuid)) { > + pr_err_once("Bad UUID for interconnect descriptor on msc %u\n", > + tbl_msc->identifier); > + return -EINVAL; > + } > + > + offset += sizeof(*tbl_int_tbl); > + offset += tbl_int_tbl->num_descriptors * sizeof(*tbl_int); > + if (offset >= tbl_msc->length) { > + pr_err_once("Bad num_descriptors for interconnect descriptor on msc %u\n", > + tbl_msc->identifier); > + return -EINVAL; > + } > + > + tbl_int = ACPI_ADD_PTR(struct acpi_mpam_interconnect_descriptor, > + tbl_int_tbl, sizeof(*tbl_int_tbl)); > + cache_id = tbl_int->source_id; > + > + /* Unknown link type? */ > + if (tbl_int->link_type != 0 && tbl_int->link_type == 1) > + return 0; > + > + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_UNKNOWN, > + 64 + tbl_int->link_type, cache_id); > default: > /* These get discovered later and are treated as unknown */ > return 0; > @@ -150,7 +235,7 @@ int acpi_mpam_parse_resources(struct mpam_msc *msc, > return -EINVAL; > } > > - err = acpi_mpam_parse_resource(msc, resource); > + err = acpi_mpam_parse_resource(tbl_msc, msc, resource); > if (err) > return err; >