From patchwork Fri Oct 12 01:06:12 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Ramirez Luna X-Patchwork-Id: 1584731 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id 07F08DFABE for ; Fri, 12 Oct 2012 01:10:33 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TMTjf-0000zg-Lf; Fri, 12 Oct 2012 01:08:20 +0000 Received: from mail-oa0-f49.google.com ([209.85.219.49]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TMTi5-0000O7-R9 for linux-arm-kernel@lists.infradead.org; Fri, 12 Oct 2012 01:06:43 +0000 Received: by mail-oa0-f49.google.com with SMTP id l10so2513381oag.36 for ; Thu, 11 Oct 2012 18:06:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :x-gm-message-state; bh=aSS4GwdAedvIDukZQifAd1uOugA2BoJJvWTRu5DyAZc=; b=DfsioYfQjKqJ6I3mT1dAbngeNDe0aoxJpVHFdzfi2+WKVVrWza59TFJQX/8oQEeq++ vWn/AD8xAq+y01WEvAWqRpNYlV4PZhDy19qpvLdJTS/momGtVx0UWa4QCOtvazxK+AfZ iT7wFpVSX5S7I1VjcJ+uE1ANGlAyYE+BsATwyqZZdbNdiZTsUDGE33fngT+cK47av0jp bWCwGp/1GMUZYzbhsFqjJ7ixYUHV+zPUIFpkl8aH+Gi97HKwAsywUrLBaOU4SJ2YoJkf fWyRg2Gbz5KPw0pYA44mgp22vUbVwxjN5KQbr/xRy0NNdcw7ToxFRDWLgnUEFv0Xc/Q+ 0Baw== Received: by 10.60.32.135 with SMTP id j7mr2149254oei.132.1350004001549; Thu, 11 Oct 2012 18:06:41 -0700 (PDT) Received: from uda0273944.am.dhcp.ti.com (dragon.ti.com. [192.94.94.33]) by mx.google.com with ESMTPS id b7sm4291259oef.12.2012.10.11.18.06.40 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 11 Oct 2012 18:06:41 -0700 (PDT) From: Omar Ramirez Luna To: Tony Lindgren , Joerg Roedel Subject: [PATCH v3 4/6] ARM: OMAP: iommu: optimize save and restore routines Date: Thu, 11 Oct 2012 20:06:12 -0500 Message-Id: <1350003977-32744-8-git-send-email-omar.luna@linaro.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1350003977-32744-1-git-send-email-omar.luna@linaro.org> References: <1350003977-32744-1-git-send-email-omar.luna@linaro.org> X-Gm-Message-State: ALoCoQnvE5id3D8LryPKaZbD1CTaunGRvqtkOPcdn+V+m9q13FSTlS0V7TTtOiDlLi+rHyNs/39g X-Spam-Note: CRM114 invocation failed X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.219.49 listed in list.dnswl.org] -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Ohad Ben-Cohen , Paul Walmsley , Russell King , Benoit Cousson , linux-doc@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, iommu@lists.linux-foundation.org, Laurent Pinchart , Omar Ramirez Luna , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org These functions save and restore registers irrespectively of their read or write permissions, this ends up in registers being saved that can't be restored because of read only attributes. OTOH, so far only 3 of them need to be saved. In future GP_REG (which is present only on OMAP4 ipu) needs to be saved but right now there is no API that can alter its value. Also, protected TLB entries must be saved but this can be in a separate patch as the original code didn't implement the loop to traverse protected TLB entries. Signed-off-by: Omar Ramirez Luna --- arch/arm/mach-omap2/iommu2.c | 38 ++++++++++++++---------------- arch/arm/plat-omap/include/plat/iommu.h | 10 +++++++- arch/arm/plat-omap/include/plat/iommu2.h | 2 -- drivers/iommu/omap-iommu.c | 3 +-- 4 files changed, 28 insertions(+), 25 deletions(-) diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c index 3e47786..cd77abb 100644 --- a/arch/arm/mach-omap2/iommu2.c +++ b/arch/arm/mach-omap2/iommu2.c @@ -19,6 +19,7 @@ #include #include +#include /* * omap2 architecture specific register bit definitions @@ -55,20 +56,26 @@ static void __iommu_set_twl(struct omap_iommu *obj, bool on) { - u32 l = iommu_read_reg(obj, MMU_CNTL); + u32 l; if (on) - iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE); + l = MMU_IRQ_TWL_MASK; else - iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE); + l = MMU_IRQ_TLB_MISS_MASK; + + iommu_write_reg(obj, l, MMU_IRQENABLE); + obj->context.irqen = l; + l = iommu_read_reg(obj, MMU_CNTL); l &= ~MMU_CNTL_MASK; + if (on) l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN); else l |= (MMU_CNTL_MMU_EN); iommu_write_reg(obj, l, MMU_CNTL); + obj->context.cntl = l; } @@ -88,6 +95,7 @@ static int omap2_iommu_enable(struct omap_iommu *obj) (l >> 4) & 0xf, l & 0xf); iommu_write_reg(obj, pa, MMU_TTB); + obj->context.ttb = pa; __iommu_set_twl(obj, true); @@ -100,6 +108,7 @@ static void omap2_iommu_disable(struct omap_iommu *obj) l &= ~MMU_CNTL_MASK; iommu_write_reg(obj, l, MMU_CNTL); + obj->context.cntl = l; dev_dbg(obj->dev, "%s is shutting down\n", obj->name); } @@ -249,28 +258,17 @@ out: static void omap2_iommu_save_ctx(struct omap_iommu *obj) { - int i; - u32 *p = obj->ctx; - - for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) { - p[i] = iommu_read_reg(obj, i * sizeof(u32)); - dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]); - } - - BUG_ON(p[0] != IOMMU_ARCH_VERSION); + obj->ctx_loss_cnt = omap_pm_get_dev_context_loss_count(obj->dev); } static void omap2_iommu_restore_ctx(struct omap_iommu *obj) { - int i; - u32 *p = obj->ctx; - - for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) { - iommu_write_reg(obj, p[i], i * sizeof(u32)); - dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]); - } + if (omap_pm_get_dev_context_loss_count(obj->dev) == obj->ctx_loss_cnt) + return; - BUG_ON(p[0] != IOMMU_ARCH_VERSION); + iommu_write_reg(obj, obj->context.ttb, MMU_TTB); + iommu_write_reg(obj, obj->context.irqen, MMU_IRQENABLE); + iommu_write_reg(obj, obj->context.cntl, MMU_CNTL); } static void omap2_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e) diff --git a/arch/arm/plat-omap/include/plat/iommu.h b/arch/arm/plat-omap/include/plat/iommu.h index 902d193..af14486 100644 --- a/arch/arm/plat-omap/include/plat/iommu.h +++ b/arch/arm/plat-omap/include/plat/iommu.h @@ -27,6 +27,13 @@ struct iotlb_entry { }; }; +/* context registers */ +struct iommu_regs { + u32 irqen; + u32 cntl; + u32 ttb; +}; + struct omap_iommu { const char *name; struct module *owner; @@ -50,7 +57,8 @@ struct omap_iommu { struct list_head mmap; struct mutex mmap_lock; /* protect mmap */ - void *ctx; /* iommu context: registres saved area */ + struct iommu_regs context; + int ctx_loss_cnt; u32 da_start; u32 da_end; }; diff --git a/arch/arm/plat-omap/include/plat/iommu2.h b/arch/arm/plat-omap/include/plat/iommu2.h index 1579694..bc43d41 100644 --- a/arch/arm/plat-omap/include/plat/iommu2.h +++ b/arch/arm/plat-omap/include/plat/iommu2.h @@ -35,8 +35,6 @@ #define MMU_READ_RAM 0x6c #define MMU_EMU_FAULT_AD 0x70 -#define MMU_REG_SIZE 256 - /* * MMU Register bit definitions */ diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c index 875e894..e266ad7 100644 --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -924,14 +924,13 @@ static int __devinit omap_iommu_probe(struct platform_device *pdev) struct resource *res; struct iommu_platform_data *pdata = pdev->dev.platform_data; - obj = kzalloc(sizeof(*obj) + MMU_REG_SIZE, GFP_KERNEL); + obj = kzalloc(sizeof(*obj), GFP_KERNEL); if (!obj) return -ENOMEM; obj->nr_tlb_entries = pdata->nr_tlb_entries; obj->name = pdata->name; obj->dev = &pdev->dev; - obj->ctx = (void *)obj + sizeof(*obj); obj->da_start = pdata->da_start; obj->da_end = pdata->da_end;