Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753209Ab3IQP3u (ORCPT ); Tue, 17 Sep 2013 11:29:50 -0400 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21]:52068 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752759Ab3IQP3t (ORCPT ); Tue, 17 Sep 2013 11:29:49 -0400 Date: Tue, 17 Sep 2013 16:28:30 +0100 From: Catalin Marinas To: Rob Herring Cc: "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , "grant.likely@linaro.org" , "rob.herring@calxeda.com" , Will Deacon , James Hogan , Michal Simek , Jonas Bonn , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "x86@kernel.org" , "linux-arm-kernel@lists.infradead.org" , "microblaze-uclinux@itee.uq.edu.au" , "linux@openrisc.net" Subject: Re: [PATCH 18/28] of: create default early_init_dt_add_memory_arch Message-ID: <20130917152829.GH16750@arm.com> References: <1379372965-22359-1-git-send-email-robherring2@gmail.com> <1379372965-22359-19-git-send-email-robherring2@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2626 Lines: 72 On Tue, Sep 17, 2013 at 02:01:36PM +0100, Rob Herring wrote: > On Tue, Sep 17, 2013 at 3:46 AM, Catalin Marinas > wrote: > > On 17 Sep 2013, at 00:09, Rob Herring wrote: > >> --- a/arch/arm64/kernel/setup.c > >> +++ b/arch/arm64/kernel/setup.c > >> @@ -147,24 +147,6 @@ static void __init setup_machine_fdt(phys_addr_t dt_phys) > >> pr_info("Machine: %s\n", machine_name); > >> } > >> > >> -void __init early_init_dt_add_memory_arch(u64 base, u64 size) > >> -{ > >> - base &= PAGE_MASK; > >> - size &= PAGE_MASK; > >> - if (base + size < PHYS_OFFSET) { > >> - pr_warning("Ignoring memory block 0x%llx - 0x%llx\n", > >> - base, base + size); > >> - return; > >> - } > >> - if (base < PHYS_OFFSET) { > >> - pr_warning("Ignoring memory range 0x%llx - 0x%llx\n", > >> - base, PHYS_OFFSET); > >> - size -= PHYS_OFFSET - base; > >> - base = PHYS_OFFSET; > >> - } > >> - memblock_add(base, size); > >> -} > >> - > >> /* > >> * Limit the memory size that was specified via FDT. > >> */ > > > > ... > > > >> --- a/drivers/of/fdt.c > >> +++ b/drivers/of/fdt.c > >> @@ -688,6 +688,17 @@ u64 __init dt_mem_next_cell(int s, __be32 **cellp) > >> return of_read_number(p, s); > >> } > >> > >> +void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) > >> +{ > >> +#ifdef CONFIG_HAVE_MEMBLOCK > >> + base &= PAGE_MASK; > >> + size &= PAGE_MASK; > >> + memblock_add(base, size); > >> +#else > >> + pr_err("%s: ignoring memory (%llx, %llx)\n", __func__, base, size); > >> +#endif > >> +} > > > > Are the arm64 changes equivalent here? There are some safety checks to > > cope with the kernel being loaded at a higher offset than the > > recommended one (PHYS_OFFSET calculated automatically). > > I tried to keep that, but PHYS_OFFSET is not universally defined. My > reasoning is this range checking is hardly specific to an > architecture. Perhaps if memory always starts at 0 you don't need it. > If arm64 really needs these checks, then all architectures do. > > Perhaps "__virt_to_phys(PAGE_OFFSET)" instead of PHYS_OFFSET would work for all? I think virt_to_phys() or __pa() should work, the __virt_to_phys() is only defined by a few architectures. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/