From patchwork Fri Jan 7 00:37:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Widawsky X-Patchwork-Id: 12706041 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 8FB7DC3526C for ; Fri, 7 Jan 2022 00:38:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344404AbiAGAiP (ORCPT ); Thu, 6 Jan 2022 19:38:15 -0500 Received: from mga18.intel.com ([134.134.136.126]:59449 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344398AbiAGAiO (ORCPT ); Thu, 6 Jan 2022 19:38:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1641515894; x=1673051894; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=s3YJ4k9WX1H2z3+76n68boGXnNFzvP0oVlTvKxnedTA=; b=cRlkBNSh7xqagjKPfVWGDcgbdQhVhyJ4ogTew0SXJx902PxIZHsxMT1m 7NYj2aWLtDWAVtQgC+btwAUFn3qThAgYtVSRXRAxe1fk/3I0cPZwQ7x0Z 57PQdHZ9/tOokARgkSm9ifLkrqgAjlOdqCM8MO0OVU8g3RgRH7ECi4CeU L54V/pt5XL0Qlhj6Rexk7Gr6zUvR/Br0uO+M+BNkq3008KbY7P8RqRcrt P8za9+HVKRbEfYLdCI7TPIFeT/90+Qe5XbR0bJvGeyezg33zVgrTQHM56 vwK3WgGJyW003Wje3bWsVJJj59G+6azafgISPyrX+kNk6P8GNF8haxLzA Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10217"; a="229582046" X-IronPort-AV: E=Sophos;i="5.88,268,1635231600"; d="scan'208";a="229582046" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2022 16:38:14 -0800 X-IronPort-AV: E=Sophos;i="5.88,268,1635231600"; d="scan'208";a="471123252" Received: from elenawei-mobl2.amr.corp.intel.com (HELO localhost.localdomain) ([10.252.138.104]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2022 16:38:14 -0800 From: Ben Widawsky To: linux-cxl@vger.kernel.org, linux-nvdimm@lists.01.org, linux-pci@vger.kernel.org Cc: patches@lists.linux.dev, Bjorn Helgaas , Ben Widawsky , Alison Schofield , Dan Williams , Ira Weiny , Jonathan Cameron , Vishal Verma Subject: [PATCH 13/13] cxl: Program decoders for regions Date: Thu, 6 Jan 2022 16:37:56 -0800 Message-Id: <20220107003756.806582-14-ben.widawsky@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220107003756.806582-1-ben.widawsky@intel.com> References: <20220107003756.806582-1-ben.widawsky@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org Do the HDM decoder programming for all endpoints and host bridges in a region. Switches are currently unimplemented. Signed-off-by: Ben Widawsky --- drivers/cxl/core/hdm.c | 198 +++++++++++++++++++++++++++++++++++++++++ drivers/cxl/cxl.h | 3 + drivers/cxl/region.c | 39 +++++++- 3 files changed, 237 insertions(+), 3 deletions(-) diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c index 44e48cea8cd4..c7293cbd8547 100644 --- a/drivers/cxl/core/hdm.c +++ b/drivers/cxl/core/hdm.c @@ -242,3 +242,201 @@ int devm_cxl_enumerate_switch_decoders(struct cxl_port *port) return 0; } EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_switch_decoders, CXL); + +#define COMMIT_TIMEOUT_MS 10 +static int wait_for_commit(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + const unsigned long start = jiffies; + struct cxl_port_state *cxlps; + void __iomem *hdm_decoder; + unsigned long end = start; + u32 ctrl; + + cxlps = dev_get_drvdata(&port->dev); + hdm_decoder = cxlps->regs.hdm_decoder; + + do { + end = jiffies; + ctrl = readl(hdm_decoder + + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) + break; + + if (time_after(end, start + COMMIT_TIMEOUT_MS)) { + dev_err(&cxld->dev, "HDM decoder commit timeout %x\n", ctrl); + return -ETIMEDOUT; + } + if ((ctrl & CXL_HDM_DECODER0_CTRL_COMMIT_ERROR) != 0) { + dev_err(&cxld->dev, "HDM decoder commit error %x\n", ctrl); + return -ENXIO; + } + } while (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)); + + return 0; +} + +/** + * cxl_commit_decoder() - Program a configured cxl_decoder + * @cxld: The preconfigured cxl decoder. + * + * A cxl decoder that is to be committed should have been earmarked as enabled. + * This mechanism acts as a soft reservation on the decoder. + * + * Returns 0 if commit was successful, negative error code otherwise. + */ +int cxl_commit_decoder(struct cxl_decoder *cxld) +{ + u32 ctrl, tl_lo, tl_hi, base_lo, base_hi, size_lo, size_hi; + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + struct cxl_port_state *cxlps; + void __iomem *hdm_decoder; + int rc; + + /* + * Decoder flags are entirely software controlled and therefore this + * case is purely a driver bug. + */ + if (dev_WARN_ONCE(&port->dev, (cxld->flags & CXL_DECODER_F_ENABLE) != 0, + "Invalid %s enable state\n", dev_name(&cxld->dev))) + return -ENXIO; + + cxlps = dev_get_drvdata(&port->dev); + hdm_decoder = cxlps->regs.hdm_decoder; + ctrl = readl(hdm_decoder + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + + /* + * A decoder that's currently active cannot be changed without the + * system being quiesced. While the driver should prevent against this, + * for a variety of reasons the hardware might not be in sync with the + * hardware and so, do not splat on error. + */ + size_hi = readl(hdm_decoder + + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(cxld->id)); + size_lo = + readl(hdm_decoder + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(cxld->id)); + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl) && + (size_lo + size_hi)) { + dev_err(&port->dev, "Tried to change an active decoder (%s)\n", + dev_name(&cxld->dev)); + return -EBUSY; + } + + u32p_replace_bits(&ctrl, 8 - ilog2(cxld->interleave_granularity), + CXL_HDM_DECODER0_CTRL_IG_MASK); + u32p_replace_bits(&ctrl, ilog2(cxld->interleave_ways), + CXL_HDM_DECODER0_CTRL_IW_MASK); + u32p_replace_bits(&ctrl, 1, CXL_HDM_DECODER0_CTRL_COMMIT); + + /* TODO: set based on type */ + u32p_replace_bits(&ctrl, 1, CXL_HDM_DECODER0_CTRL_TYPE); + + base_lo = FIELD_PREP(GENMASK(31, 28), + (u32)(cxld->decoder_range.start & 0xffffffff)); + base_hi = FIELD_PREP(~0, (u32)(cxld->decoder_range.start >> 32)); + + size_lo = (u32)(range_len(&cxld->decoder_range)) & GENMASK(31, 28); + size_hi = (u32)((range_len(&cxld->decoder_range) >> 32)); + + if (cxld->nr_targets > 0) { + tl_lo |= FIELD_PREP(GENMASK(7, 0), cxld->target[0]->port_id); + if (cxld->interleave_ways > 1) + tl_lo |= FIELD_PREP(GENMASK(15, 8), + cxld->target[1]->port_id); + if (cxld->interleave_ways > 2) + tl_lo |= FIELD_PREP(GENMASK(23, 16), + cxld->target[2]->port_id); + if (cxld->interleave_ways > 3) + tl_lo |= FIELD_PREP(GENMASK(31, 24), + cxld->target[3]->port_id); + if (cxld->interleave_ways > 4) + tl_hi |= FIELD_PREP(GENMASK(7, 0), + cxld->target[4]->port_id); + if (cxld->interleave_ways > 5) + tl_hi |= FIELD_PREP(GENMASK(15, 8), + cxld->target[5]->port_id); + if (cxld->interleave_ways > 6) + tl_hi |= FIELD_PREP(GENMASK(23, 16), + cxld->target[6]->port_id); + if (cxld->interleave_ways > 7) + tl_hi |= FIELD_PREP(GENMASK(31, 24), + cxld->target[7]->port_id); + + writel(tl_hi, hdm_decoder + CXL_HDM_DECODER0_TL_HIGH(cxld->id)); + writel(tl_lo, hdm_decoder + CXL_HDM_DECODER0_TL_LOW(cxld->id)); + } + + writel(size_hi, + hdm_decoder + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(cxld->id)); + writel(size_lo, + hdm_decoder + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(cxld->id)); + writel(base_hi, + hdm_decoder + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(cxld->id)); + writel(base_lo, + hdm_decoder + CXL_HDM_DECODER0_BASE_LOW_OFFSET(cxld->id)); + writel(ctrl, hdm_decoder + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + + rc = wait_for_commit(cxld); + if (rc) + return rc; + + cxld->flags |= CXL_DECODER_F_ENABLE; + +#define DPORT_TL_STR "%d %d %d %d %d %d %d %d" +#define DPORT(i) \ + (cxld->nr_targets && cxld->interleave_ways > (i)) ? \ + cxld->target[(i)]->port_id : \ + -1 +#define DPORT_TL \ + DPORT(0), DPORT(1), DPORT(2), DPORT(3), DPORT(4), DPORT(5), DPORT(6), \ + DPORT(7) + + dev_dbg(&port->dev, + "%s\n\tBase %pa\n\tSize %llu\n\tIG %u\n\tIW %u\n\tTargetList: " DPORT_TL_STR, + dev_name(&cxld->dev), &cxld->decoder_range.start, + range_len(&cxld->decoder_range), cxld->interleave_granularity, + cxld->interleave_ways, DPORT_TL); +#undef DPORT_TL +#undef DPORT +#undef DPORT_TL_STR + return 0; +} +EXPORT_SYMBOL_GPL(cxl_commit_decoder); + +/** + * cxl_disable_decoder() - Disables a decoder + * @cxld: The active cxl decoder. + * + * CXL decoders (as of 2.0 spec) have no way to deactivate them other than to + * set the size of the HDM to 0. This function will clear all registers, and if + * the decoder is active, commit the 0'd out registers. + */ +void cxl_disable_decoder(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + struct cxl_port_state *cxlps; + void __iomem *hdm_decoder; + u32 ctrl; + + cxlps = dev_get_drvdata(&port->dev); + hdm_decoder = cxlps->regs.hdm_decoder; + ctrl = readl(hdm_decoder + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + + if (dev_WARN_ONCE(&port->dev, (cxld->flags & CXL_DECODER_F_ENABLE) == 0, + "Invalid decoder enable state\n")) + return; + + /* There's no way to "uncommit" a committed decoder, only 0 size it */ + writel(0, hdm_decoder + CXL_HDM_DECODER0_TL_HIGH(cxld->id)); + writel(0, hdm_decoder + CXL_HDM_DECODER0_TL_LOW(cxld->id)); + writel(0, hdm_decoder + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(cxld->id)); + writel(0, hdm_decoder + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(cxld->id)); + writel(0, hdm_decoder + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(cxld->id)); + writel(0, hdm_decoder + CXL_HDM_DECODER0_BASE_LOW_OFFSET(cxld->id)); + + /* If the device isn't actually active, just zero out all the fields */ + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) + writel(CXL_HDM_DECODER0_CTRL_COMMIT, + hdm_decoder + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); +} +EXPORT_SYMBOL_GPL(cxl_disable_decoder); diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 79bca9a8246c..587b75f7fa53 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -54,6 +54,7 @@ #define CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4) #define CXL_HDM_DECODER0_CTRL_COMMIT BIT(9) #define CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10) +#define CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11) #define CXL_HDM_DECODER0_CTRL_TYPE BIT(12) #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24) #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28) @@ -364,6 +365,8 @@ int devm_cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id, struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dev); struct cxl_port *ep_find_cxl_port(struct cxl_memdev *cxlmd, unsigned int depth); +int cxl_commit_decoder(struct cxl_decoder *cxld); +void cxl_disable_decoder(struct cxl_decoder *cxld); struct cxl_decoder *to_cxl_decoder(struct device *dev); bool is_cxl_decoder(struct device *dev); diff --git a/drivers/cxl/region.c b/drivers/cxl/region.c index 3120b65b0bc5..fd82d37ba573 100644 --- a/drivers/cxl/region.c +++ b/drivers/cxl/region.c @@ -580,10 +580,30 @@ static void cleanup_staged_decoders(struct cxl_region *region) } } -static int bind_region(const struct cxl_region *region) +static int bind_region(struct cxl_region *region) { - /* TODO: */ - return 0; + struct cxl_decoder *cxld, *d; + int rc; + + list_for_each_entry_safe(cxld, d, ®ion->staged_list, region_link) { + rc = cxl_commit_decoder(cxld); + if (!rc) + list_move_tail(&cxld->region_link, ®ion->commit_list); + else + break; + } + + list_for_each_entry_safe(cxld, d, ®ion->commit_list, region_link) { + if (rc) + cxl_disable_decoder(cxld); + list_del(&cxld->region_link); + } + + if (rc) + cleanup_staged_decoders((struct cxl_region *)region); + + BUG_ON(!list_empty(®ion->staged_list)); + return rc; } static int cxl_region_probe(struct device *dev) @@ -650,9 +670,22 @@ static int cxl_region_probe(struct device *dev) return ret; } +static void cxl_region_remove(struct device *dev) +{ + struct cxl_region *region = to_cxl_region(dev); + struct cxl_decoder *cxld, *d; + + list_for_each_entry_safe(cxld, d, ®ion->commit_list, region_link) { + cxl_disable_decoder(cxld); + list_del(&cxld->region_link); + cxl_put_decoder(cxld); + } +} + static struct cxl_driver cxl_region_driver = { .name = "cxl_region", .probe = cxl_region_probe, + .remove = cxl_region_remove, .id = CXL_DEVICE_REGION, }; module_cxl_driver(cxl_region_driver);