From patchwork Wed Jul 31 16:44:42 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Santosh Shilimkar X-Patchwork-Id: 2836480 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 85AABC0319 for ; Wed, 31 Jul 2013 16:47:50 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4B6852039D for ; Wed, 31 Jul 2013 16:47:49 +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 DE6972037E for ; Wed, 31 Jul 2013 16:47:47 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4ZY3-0002E0-HL; Wed, 31 Jul 2013 16:46:52 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4ZXg-0004a7-H9; Wed, 31 Jul 2013 16:46:28 +0000 Received: from comal.ext.ti.com ([198.47.26.152]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4ZWl-0004Ui-GQ for linux-arm-kernel@lists.infradead.org; Wed, 31 Jul 2013 16:45:37 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6VGj6DD020634; Wed, 31 Jul 2013 11:45:06 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6VGj64K024686; Wed, 31 Jul 2013 11:45:06 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.2.342.3; Wed, 31 Jul 2013 11:45:06 -0500 Received: from ula0393909.am.dhcp.ti.com (ula0393909.am.dhcp.ti.com [158.218.103.117]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6VGinbF018451; Wed, 31 Jul 2013 11:45:06 -0500 From: Santosh Shilimkar To: Subject: [PATCH v2 2/6] ARM: mm: Introduce virt_to_idmap() with an arch hook Date: Wed, 31 Jul 2013 12:44:42 -0400 Message-ID: <1375289086-5315-3-git-send-email-santosh.shilimkar@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1375289086-5315-1-git-send-email-santosh.shilimkar@ti.com> References: <1375289086-5315-1-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-20130731_124531_870775_2A1DC749 X-CRM114-Status: GOOD ( 12.68 ) X-Spam-Score: -8.4 (--------) Cc: Russell King , Santosh Shilimkar , Nicolas Pitre 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=-5.7 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: Nicolas Pitre Cc: Russell King Signed-off-by: Santosh Shilimkar Acked-by: Nicolas Pitre --- 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 c2b4f8f..d36523d 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -81,7 +81,7 @@ 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;