From patchwork Thu Oct 3 21:17:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Santosh Shilimkar X-Patchwork-Id: 2986091 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 080D39F288 for ; Thu, 3 Oct 2013 21:25:12 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 33A12203A8 for ; Thu, 3 Oct 2013 21:25:11 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1844E20395 for ; Thu, 3 Oct 2013 21:25:10 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VRqNW-0007uX-Ut; Thu, 03 Oct 2013 21:24:11 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VRqId-0000vw-J6; Thu, 03 Oct 2013 21:19:07 +0000 Received: from arroyo.ext.ti.com ([192.94.94.40]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VRqIY-0000sW-IW for linux-arm-kernel@lists.infradead.org; Thu, 03 Oct 2013 21:19:04 +0000 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id r93LIYNJ026305; Thu, 3 Oct 2013 16:18:34 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id r93LIYgq008711; Thu, 3 Oct 2013 16:18:34 -0500 Received: from dflp33.itg.ti.com (10.64.6.16) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.2.342.3; Thu, 3 Oct 2013 16:18:34 -0500 Received: from ula0393909.am.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id r93LI3Bk024025; Thu, 3 Oct 2013 16:18:33 -0500 From: Santosh Shilimkar To: Subject: [PATCH v3 2/6] ARM: mm: Introduce virt_to_idmap() with an arch hook Date: Thu, 3 Oct 2013 17:17:56 -0400 Message-ID: <1380835081-12129-3-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1380835081-12129-1-git-send-email-santosh.shilimkar@ti.com> References: <1380835081-12129-1-git-send-email-santosh.shilimkar@ti.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131003_171902_747750_7E6BC21C X-CRM114-Status: GOOD ( 13.07 ) X-Spam-Score: -7.6 (-------) Cc: nicolas.pitre@linaro.org, Santosh Shilimkar , arm@kernel.org, linux@arm.linux.org.uk X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On some PAE systems (e.g. TI Keystone), memory is above the 32-bit addressable limit, and the interconnect provides an aliased view of parts of physical memory in the 32-bit addressable space. This alias is strictly for boot time usage, and is not otherwise usable because of coherency limitations. On such systems, the idmap mechanism needs to take this aliased mapping into account. This patch introduces virt_to_idmap() and a arch function pointer which can be populated by platform which needs it. Also populate necessary idmap spots with now available virt_to_idmap(). Avoided #ifdef approach to be compatible with multi-platform builds. Most architecture won't touch it and in that case virt_to_idmap() fall-back to existing virt_to_phys() macro. Cc: Russell King Acked-by: Nicolas Pitre Signed-off-by: Santosh Shilimkar --- arch/arm/include/asm/memory.h | 16 ++++++++++++++++ arch/arm/kernel/smp.c | 2 +- arch/arm/mm/idmap.c | 5 +++-- 3 files changed, 20 insertions(+), 3 deletions(-) diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index c133bd9..d9b96c65 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -173,6 +173,7 @@ */ #define __PV_BITS_31_24 0x81000000 +extern phys_addr_t (*arch_virt_to_idmap) (unsigned long x); extern unsigned long __pv_phys_offset; #define PHYS_OFFSET __pv_phys_offset @@ -259,6 +260,21 @@ static inline void *phys_to_virt(phys_addr_t x) #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) /* + * These are for systems that have a hardware interconnect supported alias of + * physical memory for idmap purposes. Most cases should leave these + * untouched. + */ +static inline phys_addr_t __virt_to_idmap(unsigned long x) +{ + if (arch_virt_to_idmap) + return arch_virt_to_idmap(x); + else + return __virt_to_phys(x); +} + +#define virt_to_idmap(x) __virt_to_idmap((unsigned long)(x)) + +/* * Virtual <-> DMA view memory address translations * Again, these are *only* valid on the kernel direct mapped RAM * memory. Use of these is *deprecated* (and that doesn't mean diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 72024ea..a0eb830 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -80,7 +80,7 @@ void __init smp_set_ops(struct smp_operations *ops) static unsigned long get_arch_pgd(pgd_t *pgd) { - phys_addr_t pgdir = virt_to_phys(pgd); + phys_addr_t pgdir = virt_to_idmap(pgd); BUG_ON(pgdir & ARCH_PGD_MASK); return pgdir >> ARCH_PGD_SHIFT; } diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c index 83cb3ac..c0a1e48 100644 --- a/arch/arm/mm/idmap.c +++ b/arch/arm/mm/idmap.c @@ -10,6 +10,7 @@ #include pgd_t *idmap_pgd; +phys_addr_t (*arch_virt_to_idmap) (unsigned long x); #ifdef CONFIG_ARM_LPAE static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end, @@ -67,8 +68,8 @@ static void identity_mapping_add(pgd_t *pgd, const char *text_start, unsigned long addr, end; unsigned long next; - addr = virt_to_phys(text_start); - end = virt_to_phys(text_end); + addr = virt_to_idmap(text_start); + end = virt_to_idmap(text_end); prot |= PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;