From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754635Ab0JYJAz (ORCPT ); Mon, 25 Oct 2010 05:00:55 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:46504 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754544Ab0JYJAs (ORCPT ); Mon, 25 Oct 2010 05:00:48 -0400 Subject: [RFC PATCH 11/18] ARM: LPAE: Add SMP support for the 3-level page table format To: linux-arm-kernel@lists.infradead.org From: Catalin Marinas Cc: linux-kernel@vger.kernel.org Date: Mon, 25 Oct 2010 10:00:35 +0100 Message-ID: <20101025090035.25275.80484.stgit@e102109-lin.cambridge.arm.com> In-Reply-To: <20101025085812.25275.55757.stgit@e102109-lin.cambridge.arm.com> References: <20101025085812.25275.55757.stgit@e102109-lin.cambridge.arm.com> User-Agent: StGit/0.15-103-g0e84 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Oct 2010 09:00:35.0893 (UTC) FILETIME=[166A3E50:01CB7423] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With 3-level page tables, starting secondary CPUs required allocating the pgd as well. Since LPAE Linux uses TTBR1 for the kernel page tables, this patch reorders the CPU setup call in the head.S file so that the swapper_pg_dir is used. TTBR0 is set to the value generated by the primary CPU. Signed-off-by: Catalin Marinas --- arch/arm/kernel/head.S | 10 +++++----- arch/arm/kernel/smp.c | 34 +++++++++++++++++++++++++++++++--- 2 files changed, 36 insertions(+), 8 deletions(-) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index eb59839..ff0aff9 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -126,6 +126,10 @@ ENTRY(secondary_startup) moveq r0, #'p' @ yes, error 'p' beq __error + pgtbl r4 + add r12, r10, #BSYM(PROCINFO_INITFUNC) + blx r12 @ initialise processor + @ (return control reg) /* * Use the page tables supplied from __cpu_up. */ @@ -133,12 +137,8 @@ ENTRY(secondary_startup) ldmia r4, {r5, r7, r12} @ address to jump to after sub r4, r4, r5 @ mmu has been enabled ldr r4, [r7, r4] @ get secondary_data.pgdir - adr lr, BSYM(__enable_mmu) @ return address mov r13, r12 @ __secondary_switched address - ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor - @ (return control reg) - THUMB( add r12, r10, #PROCINFO_INITFUNC ) - THUMB( mov pc, r12 ) + b __enable_mmu ENDPROC(secondary_startup) /* diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index fde5497..2189ca6 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -71,7 +71,7 @@ int __cpuinit __cpu_up(unsigned int cpu) { struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu); struct task_struct *idle = ci->idle; - pgd_t *pgd; + pgd_t *pgd, *pgd_phys; pmd_t *pmd; int ret; @@ -101,9 +101,32 @@ int __cpuinit __cpu_up(unsigned int cpu) * a 1:1 mapping for the physical address of the kernel. */ pgd = pgd_alloc(&init_mm); - pmd = pmd_offset(pgd + pgd_index(PHYS_OFFSET), PHYS_OFFSET); + if (!pgd) { + ret = -ENOMEM; + goto out; + } + pgd_phys = pgd + pgd_index(PHYS_OFFSET); +#ifdef CONFIG_ARM_LPAE + /* + * Check for overlapping between PHYS_OFFSET and PAGE_OFFSET and + * duplicate the pmd to avoid overriding valid kernel mappings in the + * init_mm page tables. + */ + pmd = pmd_alloc_one(NULL, PHYS_OFFSET); + if (!pmd) { + ret = -ENOMEM; + goto nopmd; + } + if (pgd_present(*pgd_phys)) + memcpy(pmd, pmd_offset(pgd_phys, 0), + PTRS_PER_PMD * sizeof(pmd_t)); + pgd_populate(NULL, pgd_phys, pmd); +#endif + pmd = pmd_offset(pgd_phys, PHYS_OFFSET); *pmd = __pmd((PHYS_OFFSET & PMD_MASK) | - PMD_TYPE_SECT | PMD_SECT_AP_WRITE); + PMD_TYPE_SECT | PMD_SECT_AP_WRITE | + PMD_SECT_AP_READ | PMD_SECT_AF | + PMD_SECT_WBWA | PMD_SECT_S); flush_pmd_entry(pmd); outer_clean_range(__pa(pmd), __pa(pmd + 1)); @@ -145,8 +168,13 @@ int __cpuinit __cpu_up(unsigned int cpu) *pmd = __pmd(0); clean_pmd_entry(pmd); +#ifdef CONFIG_ARM_LPAE + pmd_free(&init_mm, pmd_offset(pgd_phys, 0)); +nopmd: +#endif pgd_free(&init_mm, pgd); +out: if (ret) { printk(KERN_CRIT "CPU%u: processor failed to boot\n", cpu);