From patchwork Wed Nov 30 22:47:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alison Schofield X-Patchwork-Id: 13060540 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6638C47088 for ; Wed, 30 Nov 2022 22:47:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229694AbiK3Wrj (ORCPT ); Wed, 30 Nov 2022 17:47:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54986 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229624AbiK3Wrh (ORCPT ); Wed, 30 Nov 2022 17:47:37 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66D98C5C for ; Wed, 30 Nov 2022 14:47:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1669848455; x=1701384455; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=VR2EM7y4qFxVXtySed340ALUw9Ek194gIh6mitn2riY=; b=Uk6d8AeVRBNFrbj0IfyBwbK0/AcFrHIdpBPJVZMROQe0rtdqUfuE5Gi/ dtJwH43Tg3AoMgNFhmHixmLbDZxXFlL5re57xN6oLyNl4EZC9jhIHbgBf /vmnVHZp5lm144GgQGvi315kf1Co8cjLeLJ27oHClIRKf4JnQjnm4w1vM WVHhFsYH7l5NUSKOA/VZws1dxdgLSq8bwVXRJfb/F0VV0DZ9CR0NlBgM5 jmq9Dy23u90kGoA1Zl2TO6AK5olckaFuhcQ8YpaFmtH1eJ4PSHK0LUXlG WRfqwq/ex9cF+No8gyvW1jippFeqaYvQRksD4hfJQ/V4l97WqJd+Geiw2 g==; X-IronPort-AV: E=McAfee;i="6500,9779,10547"; a="316682639" X-IronPort-AV: E=Sophos;i="5.96,207,1665471600"; d="scan'208";a="316682639" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2022 14:47:31 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10547"; a="769003143" X-IronPort-AV: E=Sophos;i="5.96,207,1665471600"; d="scan'208";a="769003143" Received: from aschofie-mobl2.amr.corp.intel.com (HELO localhost) ([10.209.3.88]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Nov 2022 14:47:31 -0800 From: alison.schofield@intel.com To: Dan Williams , Ira Weiny , Vishal Verma , Ben Widawsky , Dave Jiang Cc: Alison Schofield , linux-cxl@vger.kernel.org, Jonathan Cameron Subject: [PATCH v9 2/3] cxl/acpi: Support CXL XOR Interleave Math (CXIMS) Date: Wed, 30 Nov 2022 14:47:25 -0800 Message-Id: <5794813acdf7b67cfba3609c6aaff46932fa38d0.1669847017.git.alison.schofield@intel.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org From: Alison Schofield When the CFMWS is using XOR math, parse the corresponding CXIMS structure and store the xormaps in the root decoder structure. Use the xormaps in a new lookup, cxl_hb_xor(), to find a targets entry in the host bridge interleave target list. Defined in CXL Specfication 3.0 Section: 9.17.1 Signed-off-by: Alison Schofield Reviewed-by: Jonathan Cameron --- drivers/cxl/acpi.c | 136 +++++++++++++++++++++++++++++++++++++++- drivers/cxl/core/port.c | 9 ++- drivers/cxl/cxl.h | 11 +++- 3 files changed, 148 insertions(+), 8 deletions(-) diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c index fb649683dd3a..8eee0aa49a77 100644 --- a/drivers/cxl/acpi.c +++ b/drivers/cxl/acpi.c @@ -6,9 +6,117 @@ #include #include #include +#include #include "cxlpci.h" #include "cxl.h" +struct cxl_cxims_data { + int nr_maps; + u64 xormaps[]; +}; + +/* + * Find a targets entry (n) in the host bridge interleave list. + * CXL Specfication 3.0 Table 9-22 + */ +static int cxl_xor_calc_n(u64 hpa, struct cxl_cxims_data *cximsd, int iw, + int ig) +{ + int i = 0, n = 0; + u8 eiw; + + /* IW: 2,4,6,8,12,16 begin building 'n' using xormaps */ + if (iw != 3) { + for (i = 0; i < cximsd->nr_maps; i++) + n |= (hweight64(hpa & cximsd->xormaps[i]) & 1) << i; + } + /* IW: 3,6,12 add a modulo calculation to 'n' */ + if (!is_power_of_2(iw)) { + if (ways_to_cxl(iw, &eiw)) + return -1; + hpa &= GENMASK_ULL(51, eiw + ig); + n |= do_div(hpa, 3) << i; + } + return n; +} + +static struct cxl_dport *cxl_hb_xor(struct cxl_root_decoder *cxlrd, int pos) +{ + struct cxl_cxims_data *cximsd = cxlrd->platform_data; + struct cxl_switch_decoder *cxlsd = &cxlrd->cxlsd; + struct cxl_decoder *cxld = &cxlsd->cxld; + int ig = cxld->interleave_granularity; + int iw = cxld->interleave_ways; + int n = 0; + u64 hpa; + + if (dev_WARN_ONCE(&cxld->dev, + cxld->interleave_ways != cxlsd->nr_targets, + "misconfigured root decoder\n")) + return NULL; + + hpa = cxlrd->res->start + pos * ig; + + /* Entry (n) is 0 for no interleave (iw == 1) */ + if (iw != 1) + n = cxl_xor_calc_n(hpa, cximsd, iw, ig); + + if (n < 0) + return NULL; + + return cxlrd->cxlsd.target[n]; +} + +struct cxl_cxims_context { + struct device *dev; + struct cxl_root_decoder *cxlrd; +}; + +static int cxl_parse_cxims(union acpi_subtable_headers *header, void *arg, + const unsigned long end) +{ + struct acpi_cedt_cxims *cxims = (struct acpi_cedt_cxims *)header; + struct cxl_cxims_context *ctx = arg; + struct cxl_root_decoder *cxlrd = ctx->cxlrd; + struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; + struct device *dev = ctx->dev; + struct cxl_cxims_data *cximsd; + unsigned int hbig, nr_maps; + int rc; + + rc = cxl_to_granularity(cxims->hbig, &hbig); + if (rc) + return rc; + + if (hbig == cxld->interleave_granularity) { + /* IW 1,3 do not use xormaps and skip this parsing entirely */ + + if (is_power_of_2(cxld->interleave_ways)) + /* 2, 4, 8, 16 way */ + nr_maps = ilog2(cxld->interleave_ways); + else + /* 6, 12 way */ + nr_maps = ilog2(cxld->interleave_ways / 3); + + if (cxims->nr_xormaps < nr_maps) { + dev_dbg(dev, "CXIMS nr_xormaps[%d] expected[%d]\n", + cxims->nr_xormaps, nr_maps); + return -ENXIO; + } + + cximsd = devm_kzalloc(dev, + struct_size(cximsd, xormaps, nr_maps), + GFP_KERNEL); + if (!cximsd) + return -ENOMEM; + memcpy(cximsd->xormaps, cxims->xormap_list, + nr_maps * sizeof(*cximsd->xormaps)); + cximsd->nr_maps = nr_maps; + cxlrd->platform_data = cximsd; + } + return 0; +} + static unsigned long cfmws_to_decoder_flags(int restrictions) { unsigned long flags = CXL_DECODER_F_ENABLE; @@ -33,8 +141,10 @@ static int cxl_acpi_cfmws_verify(struct device *dev, int rc, expected_len; unsigned int ways; - if (cfmws->interleave_arithmetic != ACPI_CEDT_CFMWS_ARITHMETIC_MODULO) { - dev_err(dev, "CFMWS Unsupported Interleave Arithmetic\n"); + if (cfmws->interleave_arithmetic != ACPI_CEDT_CFMWS_ARITHMETIC_MODULO && + cfmws->interleave_arithmetic != ACPI_CEDT_CFMWS_ARITHMETIC_XOR) { + dev_err(dev, "CFMWS Unknown Interleave Arithmetic: %d\n", + cfmws->interleave_arithmetic); return -EINVAL; } @@ -84,9 +194,11 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, struct cxl_cfmws_context *ctx = arg; struct cxl_port *root_port = ctx->root_port; struct resource *cxl_res = ctx->cxl_res; + struct cxl_cxims_context cxims_ctx; struct cxl_root_decoder *cxlrd; struct device *dev = ctx->dev; struct acpi_cedt_cfmws *cfmws; + cxl_calc_hb_fn cxl_calc_hb; struct cxl_decoder *cxld; unsigned int ways, i, ig; struct resource *res; @@ -128,7 +240,12 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, if (rc) goto err_insert; - cxlrd = cxl_root_decoder_alloc(root_port, ways); + if (cfmws->interleave_arithmetic == ACPI_CEDT_CFMWS_ARITHMETIC_MODULO) + cxl_calc_hb = cxl_hb_modulo; + else + cxl_calc_hb = cxl_hb_xor; + + cxlrd = cxl_root_decoder_alloc(root_port, ways, cxl_calc_hb); if (IS_ERR(cxlrd)) return 0; @@ -148,7 +265,20 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, ig = CXL_DECODER_MIN_GRANULARITY; cxld->interleave_granularity = ig; + if (cfmws->interleave_arithmetic == ACPI_CEDT_CFMWS_ARITHMETIC_XOR) { + if (ways != 1 && ways != 3) { + cxims_ctx = (struct cxl_cxims_context) { + .dev = dev, + .cxlrd = cxlrd, + }; + rc = acpi_table_parse_cedt(ACPI_CEDT_TYPE_CXIMS, + cxl_parse_cxims, &cxims_ctx); + if (rc < 0) + goto err_xormap; + } + } rc = cxl_decoder_add(cxld, target_map); +err_xormap: if (rc) put_device(&cxld->dev); else diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index e7556864ea80..42cdf224a85d 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -1428,7 +1428,7 @@ static int decoder_populate_targets(struct cxl_switch_decoder *cxlsd, return rc; } -static struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos) +struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos) { struct cxl_switch_decoder *cxlsd = &cxlrd->cxlsd; struct cxl_decoder *cxld = &cxlsd->cxld; @@ -1441,6 +1441,7 @@ static struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos) return cxlrd->cxlsd.target[pos % iw]; } +EXPORT_SYMBOL_NS_GPL(cxl_hb_modulo, CXL); static struct lock_class_key cxl_decoder_key; @@ -1502,6 +1503,7 @@ static int cxl_switch_decoder_init(struct cxl_port *port, * cxl_root_decoder_alloc - Allocate a root level decoder * @port: owning CXL root of this decoder * @nr_targets: static number of downstream targets + * @calc_hb: which host bridge covers the n'th position by granularity * * Return: A new cxl decoder to be registered by cxl_decoder_add(). A * 'CXL root' decoder is one that decodes from a top-level / static platform @@ -1509,7 +1511,8 @@ static int cxl_switch_decoder_init(struct cxl_port *port, * topology. */ struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets) + unsigned int nr_targets, + cxl_calc_hb_fn calc_hb) { struct cxl_root_decoder *cxlrd; struct cxl_switch_decoder *cxlsd; @@ -1531,7 +1534,7 @@ struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port, return ERR_PTR(rc); } - cxlrd->calc_hb = cxl_hb_modulo; + cxlrd->calc_hb = calc_hb; cxld = &cxlsd->cxld; cxld->dev.type = &cxl_decoder_root_type; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index ac75554b5d76..5f611b8a37cf 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -324,18 +324,23 @@ struct cxl_switch_decoder { struct cxl_dport *target[]; }; +struct cxl_root_decoder; +typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd, + int pos); /** * struct cxl_root_decoder - Static platform CXL address decoder * @res: host / parent resource for region allocations * @region_id: region id for next region provisioning event * @calc_hb: which host bridge covers the n'th position by granularity + * @platform_data: platform specific configuration data * @cxlsd: base cxl switch decoder */ struct cxl_root_decoder { struct resource *res; atomic_t region_id; - struct cxl_dport *(*calc_hb)(struct cxl_root_decoder *cxlrd, int pos); + cxl_calc_hb_fn calc_hb; + void *platform_data; struct cxl_switch_decoder cxlsd; }; @@ -581,7 +586,9 @@ struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev); bool is_root_decoder(struct device *dev); bool is_endpoint_decoder(struct device *dev); struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets); + unsigned int nr_targets, + cxl_calc_hb_fn calc_hb); +struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos); struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, unsigned int nr_targets); int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);