From patchwork Wed Jun 27 11:38:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10491231 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 69948602B3 for ; Wed, 27 Jun 2018 11:39:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5856928C29 for ; Wed, 27 Jun 2018 11:39:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C95C28C9A; Wed, 27 Jun 2018 11:39:03 +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 A7F7028C29 for ; Wed, 27 Jun 2018 11:39:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6AF3E6E8C4; Wed, 27 Jun 2018 11:39:00 +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 5CF686E8C0 for ; Wed, 27 Jun 2018 11:38:58 +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 12174376-1500050 for multiple; Wed, 27 Jun 2018 12:38:51 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Wed, 27 Jun 2018 12:38:50 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Wed, 27 Jun 2018 12:38:41 +0100 Message-Id: <20180627113843.7257-4-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180627113843.7257-1-chris@chris-wilson.co.uk> References: <20180627113843.7257-1-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 4/6] 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 d3264bd6e9dc..7209c22798e6 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 91656eb2f2db..368a8c74d11d 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" @@ -953,44 +954,23 @@ 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; @@ -1016,12 +996,12 @@ 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, @@ -1103,16 +1083,11 @@ static void process_csb(struct intel_engine_cs *engine) } else { port_set(port, port_pack(rq, count)); } - } + } while (head != tail); - 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))); - } - - 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; } /* @@ -2430,28 +2405,11 @@ 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); @@ -2459,34 +2417,56 @@ 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 a0bc7a8222b4..5b92c5f03e1d 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