From patchwork Fri Aug 8 23:40:42 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Scott Wood X-Patchwork-Id: 378701 X-Patchwork-Delegate: scottwood@freescale.com Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C7EBE14011D for ; Sat, 9 Aug 2014 09:41:46 +1000 (EST) Received: from ozlabs.org (ozlabs.org [103.22.144.67]) by lists.ozlabs.org (Postfix) with ESMTP id 647FD1A0AC6 for ; Sat, 9 Aug 2014 09:41:46 +1000 (EST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from na01-by2-obe.outbound.protection.outlook.com (mail-by2lp0239.outbound.protection.outlook.com [207.46.163.239]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 7085B1A0A6A for ; Sat, 9 Aug 2014 09:41:09 +1000 (EST) Received: from snotra.am.freescale.net (192.88.168.49) by BN1PR0301MB0723.namprd03.prod.outlook.com (25.160.78.142) with Microsoft SMTP Server (TLS) id 15.0.1005.10; Fri, 8 Aug 2014 23:40:54 +0000 From: Scott Wood To: Benjamin Herrenschmidt Subject: [PATCH 1/4] powerpc: Dynamic DMA zone limits Date: Fri, 8 Aug 2014 18:40:42 -0500 Message-ID: <1407541245-27617-1-git-send-email-scottwood@freescale.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 X-Originating-IP: [192.88.168.49] X-ClientProxiedBy: BLUPR05CA0049.namprd05.prod.outlook.com (10.141.20.19) To BN1PR0301MB0723.namprd03.prod.outlook.com (25.160.78.142) X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:;UriScan:; X-Forefront-PRVS: 02973C87BC X-Forefront-Antispam-Report: SFV:NSPM; SFS:(6009001)(199002)(189002)(50986999)(19580395003)(19580405001)(87286001)(83322001)(110136001)(66066001)(62966002)(74662001)(33646002)(31966008)(74502001)(99396002)(85306004)(88136002)(89996001)(102836001)(46102001)(101416001)(104166001)(87976001)(76482001)(36756003)(79102001)(77982001)(77156001)(42186005)(86362001)(575784001)(83072002)(92566001)(92726001)(85852003)(50466002)(48376002)(106356001)(81342001)(20776003)(81542001)(21056001)(4396001)(95666004)(64706001)(229853001)(47776003)(107046002)(80022001)(50226001)(105586002)(77096002)(93916002); DIR:OUT; SFP:; SCL:1; SRVR:BN1PR0301MB0723; H:snotra.am.freescale.net; FPR:; MLV:sfv; PTR:InfoNoRecords; MX:1; LANG:en; X-OriginatorOrg: freescale.com Cc: Scott Wood , linuxppc-dev@lists.ozlabs.org, Shaohui Xie X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Platform code can call limit_zone_pfn() to set appropriate limits for ZONE_DMA and ZONE_DMA32, and dma_direct_alloc_coherent() will select a suitable zone based on a device's mask and the pfn limits that platform code has configured. Signed-off-by: Scott Wood Cc: Shaohui Xie --- arch/powerpc/Kconfig | 4 +++ arch/powerpc/include/asm/pgtable.h | 3 ++ arch/powerpc/kernel/dma.c | 20 +++++++++++++ arch/powerpc/mm/mem.c | 61 ++++++++++++++++++++++++++++++++++---- 4 files changed, 83 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 80b94b0..56dc47a 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -286,6 +286,10 @@ config PPC_EMULATE_SSTEP bool default y if KPROBES || UPROBES || XMON || HAVE_HW_BREAKPOINT +config ZONE_DMA32 + bool + default y if PPC64 + source "init/Kconfig" source "kernel/Kconfig.freezer" diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index d98c1ec..6d74167 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -4,6 +4,7 @@ #ifndef __ASSEMBLY__ #include +#include #include /* For TASK_SIZE */ #include #include @@ -281,6 +282,8 @@ extern unsigned long empty_zero_page[]; extern pgd_t swapper_pg_dir[]; +void limit_zone_pfn(enum zone_type zone, unsigned long max_pfn); +int dma_pfn_limit_to_zone(u64 pfn_limit); extern void paging_init(void); /* diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c index ee78f6e..dfd99ef 100644 --- a/arch/powerpc/kernel/dma.c +++ b/arch/powerpc/kernel/dma.c @@ -40,6 +40,26 @@ void *dma_direct_alloc_coherent(struct device *dev, size_t size, #else struct page *page; int node = dev_to_node(dev); + u64 pfn = (dev->coherent_dma_mask >> PAGE_SHIFT) + 1; + int zone; + + zone = dma_pfn_limit_to_zone(pfn); + if (zone < 0) { + dev_err(dev, "%s: No suitable zone for pfn %#llx\n", + __func__, pfn); + return NULL; + } + + switch (zone) { + case ZONE_DMA: + flag |= GFP_DMA; + break; +#ifdef CONFIG_ZONE_DMA32 + case ZONE_DMA32: + flag |= GFP_DMA32; + break; +#endif + }; /* ignore region specifiers */ flag &= ~(__GFP_HIGHMEM); diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index e0f7a18..3b23e17 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -261,6 +261,54 @@ static int __init mark_nonram_nosave(void) return 0; } +static bool zone_limits_final; + +static unsigned long max_zone_pfns[MAX_NR_ZONES] = { + [0 ... MAX_NR_ZONES - 1] = ~0UL +}; + +/* + * Restrict the specified zone and all more restrictive zones + * to be below the specified pfn. May not be called after + * paging_init(). + */ +void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit) +{ + int i; + + if (WARN_ON(zone_limits_final)) + return; + + for (i = zone; i >= 0; i--) { + if (max_zone_pfns[i] > pfn_limit) + max_zone_pfns[i] = pfn_limit; + } +} + +/* + * Find the least restrictive zone that is entirely below the + * specified pfn limit. Returns < 0 if no suitable zone is found. + * + * pfn_limit must be u64 because it can exceed 32 bits even on 32-bit + * systems -- the DMA limit can be higher than any possible real pfn. + */ +int dma_pfn_limit_to_zone(u64 pfn_limit) +{ + enum zone_type top_zone = ZONE_NORMAL; + int i; + +#ifdef CONFIG_HIGHMEM + top_zone = ZONE_HIGHMEM; +#endif + + for (i = top_zone; i >= 0; i--) { + if (max_zone_pfns[i] <= pfn_limit) + return i; + } + + return -EPERM; +} + /* * paging_init() sets up the page tables - in fact we've already done this. */ @@ -268,7 +316,7 @@ void __init paging_init(void) { unsigned long long total_ram = memblock_phys_mem_size(); phys_addr_t top_of_ram = memblock_end_of_DRAM(); - unsigned long max_zone_pfns[MAX_NR_ZONES]; + enum zone_type top_zone; #ifdef CONFIG_PPC32 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); @@ -290,13 +338,16 @@ void __init paging_init(void) (unsigned long long)top_of_ram, total_ram); printk(KERN_DEBUG "Memory hole size: %ldMB\n", (long int)((top_of_ram - total_ram) >> 20)); - memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); + #ifdef CONFIG_HIGHMEM - max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT; - max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT; + top_zone = ZONE_HIGHMEM; + limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT); #else - max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; + top_zone = ZONE_NORMAL; #endif + + limit_zone_pfn(top_zone, top_of_ram >> PAGE_SHIFT); + zone_limits_final = true; free_area_init_nodes(max_zone_pfns); mark_nonram_nosave();