From patchwork Fri Jun 15 19:10:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10467417 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5FA0F60384 for ; Fri, 15 Jun 2018 19:11:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4F38B28E41 for ; Fri, 15 Jun 2018 19:11:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 43BF028E46; Fri, 15 Jun 2018 19:11:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A5B0028E41 for ; Fri, 15 Jun 2018 19:11:26 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7CAA76EC23; Fri, 15 Jun 2018 19:11:25 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0CD3E6EBEF for ; Fri, 15 Jun 2018 19:11:18 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 12062428-1500050 for multiple; Fri, 15 Jun 2018 20:11:12 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Fri, 15 Jun 2018 20:11:13 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Fri, 15 Jun 2018 20:10:48 +0100 Message-Id: <20180615191105.17009-4-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180615191105.17009-1-chris@chris-wilson.co.uk> References: <20180615191105.17009-1-chris@chris-wilson.co.uk> X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [PATCH 04/21] drm/i915/execlists: Unify CSB access pointers X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Following the removal of the last workarounds, the only CSB mmio access is for the old vGPU interface. The mmio registers presented by vGPU do not require forcewake and can be treated as ordinary volatile memory, i.e. they behave just like the HWSP access just at a different location. We can reduce the CSB access to a set of read/write/buffer pointers and treat the various paths identically and not worry about forcewake. (Forcewake is nightmare for worstcase latency, and we want to process this all with irqsoff -- no latency allowed!) Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/intel_engine_cs.c | 12 --- drivers/gpu/drm/i915/intel_lrc.c | 116 ++++++++++-------------- drivers/gpu/drm/i915/intel_ringbuffer.h | 23 +++-- 3 files changed, 65 insertions(+), 86 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c index 13bb8c7d2621..db0121f8d423 100644 --- a/drivers/gpu/drm/i915/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/intel_engine_cs.c @@ -25,7 +25,6 @@ #include #include "i915_drv.h" -#include "i915_vgpu.h" #include "intel_ringbuffer.h" #include "intel_lrc.h" @@ -456,21 +455,10 @@ static void intel_engine_init_batch_pool(struct intel_engine_cs *engine) i915_gem_batch_pool_init(&engine->batch_pool, engine); } -static bool csb_force_mmio(struct drm_i915_private *i915) -{ - /* Older GVT emulation depends upon intercepting CSB mmio */ - if (intel_vgpu_active(i915) && !intel_vgpu_has_hwsp_emulation(i915)) - return true; - - return false; -} - static void intel_engine_init_execlist(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; - execlists->csb_use_mmio = csb_force_mmio(engine->i915); - execlists->port_mask = 1; BUILD_BUG_ON_NOT_POWER_OF_2(execlists_num_ports(execlists)); GEM_BUG_ON(execlists_num_ports(execlists) > EXECLIST_MAX_PORTS); diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 80b5df92f8de..0b584b87e13e 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -137,6 +137,7 @@ #include #include "i915_drv.h" #include "i915_gem_render_state.h" +#include "i915_vgpu.h" #include "intel_lrc_reg.h" #include "intel_mocs.h" #include "intel_workarounds.h" @@ -959,44 +960,23 @@ static void process_csb(struct intel_engine_cs *engine) { struct intel_engine_execlists * const execlists = &engine->execlists; struct execlist_port *port = execlists->port; - struct drm_i915_private *i915 = engine->i915; - - /* The HWSP contains a (cacheable) mirror of the CSB */ - const u32 *buf = - &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX]; - unsigned int head, tail; - bool fw = false; + const u32 * const buf = execlists->csb_status; + u8 head, tail; /* Clear before reading to catch new interrupts */ clear_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted); smp_mb__after_atomic(); - if (unlikely(execlists->csb_use_mmio)) { - intel_uncore_forcewake_get(i915, execlists->fw_domains); - fw = true; - - buf = (u32 * __force) - (i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_BUF_LO(engine, 0))); + /* Note that csb_write, csb_status may be either in HWSP or mmio */ + head = execlists->csb_head; + tail = READ_ONCE(*execlists->csb_write); + GEM_TRACE("%s cs-irq head=%d, tail=%d\n", engine->name, head, tail); + if (unlikely(head == tail)) + return; - head = readl(i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine))); - tail = GEN8_CSB_WRITE_PTR(head); - head = GEN8_CSB_READ_PTR(head); - execlists->csb_head = head; - } else { - const int write_idx = - intel_hws_csb_write_index(i915) - - I915_HWS_CSB_BUF0_INDEX; + rmb(); /* Hopefully paired with a wmb() in HW */ - head = execlists->csb_head; - tail = READ_ONCE(buf[write_idx]); - rmb(); /* Hopefully paired with a wmb() in HW */ - } - GEM_TRACE("%s cs-irq head=%d [%d%s], tail=%d [%d%s]\n", - engine->name, - head, GEN8_CSB_READ_PTR(readl(i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine)))), fw ? "" : "?", - tail, GEN8_CSB_WRITE_PTR(readl(i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine)))), fw ? "" : "?"); - - while (head != tail) { + do { struct i915_request *rq; unsigned int status; unsigned int count; @@ -1022,12 +1002,12 @@ static void process_csb(struct intel_engine_cs *engine) * status notifier. */ - status = READ_ONCE(buf[2 * head]); /* maybe mmio! */ GEM_TRACE("%s csb[%d]: status=0x%08x:0x%08x, active=0x%x\n", engine->name, head, - status, buf[2*head + 1], + buf[2 * head + 0], buf[2 * head + 1], execlists->active); + status = buf[2 * head]; if (status & (GEN8_CTX_STATUS_IDLE_ACTIVE | GEN8_CTX_STATUS_PREEMPTED)) execlists_set_active(execlists, @@ -1109,16 +1089,11 @@ static void process_csb(struct intel_engine_cs *engine) } else { port_set(port, port_pack(rq, count)); } - } - - if (head != execlists->csb_head) { - execlists->csb_head = head; - writel(_MASKED_FIELD(GEN8_CSB_READ_PTR_MASK, head << 8), - i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine))); - } + } while (head != tail); - if (unlikely(fw)) - intel_uncore_forcewake_put(i915, execlists->fw_domains); + writel(_MASKED_FIELD(GEN8_CSB_READ_PTR_MASK, head << 8), + execlists->csb_read); + execlists->csb_head = head; } /* @@ -2396,28 +2371,11 @@ logical_ring_default_irqs(struct intel_engine_cs *engine) static void logical_ring_setup(struct intel_engine_cs *engine) { - struct drm_i915_private *dev_priv = engine->i915; - enum forcewake_domains fw_domains; - intel_engine_setup_common(engine); /* Intentionally left blank. */ engine->buffer = NULL; - fw_domains = intel_uncore_forcewake_for_reg(dev_priv, - RING_ELSP(engine), - FW_REG_WRITE); - - fw_domains |= intel_uncore_forcewake_for_reg(dev_priv, - RING_CONTEXT_STATUS_PTR(engine), - FW_REG_READ | FW_REG_WRITE); - - fw_domains |= intel_uncore_forcewake_for_reg(dev_priv, - RING_CONTEXT_STATUS_BUF_BASE(engine), - FW_REG_READ); - - engine->execlists.fw_domains = fw_domains; - tasklet_init(&engine->execlists.tasklet, execlists_submission_tasklet, (unsigned long)engine); @@ -2425,34 +2383,56 @@ logical_ring_setup(struct intel_engine_cs *engine) logical_ring_default_irqs(engine); } +static bool csb_force_mmio(struct drm_i915_private *i915) +{ + /* Older GVT emulation depends upon intercepting CSB mmio */ + return intel_vgpu_active(i915) && !intel_vgpu_has_hwsp_emulation(i915); +} + static int logical_ring_init(struct intel_engine_cs *engine) { + struct drm_i915_private *i915 = engine->i915; + struct intel_engine_execlists * const execlists = &engine->execlists; int ret; ret = intel_engine_init_common(engine); if (ret) goto error; - if (HAS_LOGICAL_RING_ELSQ(engine->i915)) { - engine->execlists.submit_reg = engine->i915->regs + + if (HAS_LOGICAL_RING_ELSQ(i915)) { + execlists->submit_reg = i915->regs + i915_mmio_reg_offset(RING_EXECLIST_SQ_CONTENTS(engine)); - engine->execlists.ctrl_reg = engine->i915->regs + + execlists->ctrl_reg = i915->regs + i915_mmio_reg_offset(RING_EXECLIST_CONTROL(engine)); } else { - engine->execlists.submit_reg = engine->i915->regs + + execlists->submit_reg = i915->regs + i915_mmio_reg_offset(RING_ELSP(engine)); } - engine->execlists.preempt_complete_status = ~0u; - if (engine->i915->preempt_context) { + execlists->preempt_complete_status = ~0u; + if (i915->preempt_context) { struct intel_context *ce = - to_intel_context(engine->i915->preempt_context, engine); + to_intel_context(i915->preempt_context, engine); - engine->execlists.preempt_complete_status = + execlists->preempt_complete_status = upper_32_bits(ce->lrc_desc); } - engine->execlists.csb_head = GEN8_CSB_ENTRIES - 1; + execlists->csb_head = GEN8_CSB_ENTRIES - 1; + execlists->csb_read = + i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine)); + if (csb_force_mmio(i915)) { + execlists->csb_status = (u32 __force *) + (i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_BUF_LO(engine, 0))); + + execlists->csb_write = (u32 __force *)execlists->csb_read; + } else { + execlists->csb_status = + &engine->status_page.page_addr[I915_HWS_CSB_BUF0_INDEX]; + + execlists->csb_write = + &engine->status_page.page_addr[intel_hws_csb_write_index(i915)]; + } return 0; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index 4003f3ebe3d1..2e0f0d33f339 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -300,19 +300,30 @@ struct intel_engine_execlists { struct rb_node *first; /** - * @fw_domains: forcewake domains for irq tasklet + * @csb_head: context status buffer head */ - unsigned int fw_domains; + unsigned int csb_head; /** - * @csb_head: context status buffer head + * @csb_read: control register for Context Switch buffer + * + * Note this register is always in mmio. */ - unsigned int csb_head; + u32 __iomem *csb_read; /** - * @csb_use_mmio: access csb through mmio, instead of hwsp + * @csb_write: control register for Context Switch buffer + * + * Note this register may be either mmio or HWSP shadow. + */ + u32 *csb_write; + + /** + * @csb_status: status array for Context Switch buffer + * + * Note these register may be either mmio or HWSP shadow. */ - bool csb_use_mmio; + u32 *csb_status; /** * @preempt_complete_status: expected CSB upon completing preemption