From patchwork Sat Nov 7 10:55:55 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matt Fleming X-Patchwork-Id: 58312 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id nA7AsK46001651 for ; Sat, 7 Nov 2009 10:56:05 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751135AbZKGKz7 (ORCPT ); Sat, 7 Nov 2009 05:55:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751176AbZKGKz7 (ORCPT ); Sat, 7 Nov 2009 05:55:59 -0500 Received: from 124x34x33x190.ap124.ftth.ucom.ne.jp ([124.34.33.190]:52517 "EHLO master.linux-sh.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751135AbZKGKz5 (ORCPT ); Sat, 7 Nov 2009 05:55:57 -0500 Received: from localhost (unknown [127.0.0.1]) by master.linux-sh.org (Postfix) with ESMTP id BDA2163777; Sat, 7 Nov 2009 10:55:38 +0000 (UTC) X-Quarantine-ID: X-Virus-Scanned: amavisd-new at linux-sh.org X-Amavis-Alert: BAD HEADER, Duplicate header field: "In-Reply-To" Received: from master.linux-sh.org ([127.0.0.1]) by localhost (master.linux-sh.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qlx5j00PWazy; Sat, 7 Nov 2009 19:55:37 +0900 (JST) Received: from localhost (82-38-64-26.cable.ubr06.brad.blueyonder.co.uk [82.38.64.26]) by master.linux-sh.org (Postfix) with ESMTP id 9C64A63758; Sat, 7 Nov 2009 19:55:36 +0900 (JST) From: Matt Fleming To: Paul Mundt Cc: linux-sh@vger.kernel.org Subject: [PATCH 1/3] sh: Add fixed ioremap support Date: Sat, 7 Nov 2009 10:55:55 +0000 Message-Id: X-Mailer: git-send-email 1.6.2.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org diff --git a/arch/sh/include/asm/fixmap.h b/arch/sh/include/asm/fixmap.h index 76c5a30..e2da609 100644 --- a/arch/sh/include/asm/fixmap.h +++ b/arch/sh/include/asm/fixmap.h @@ -54,6 +54,14 @@ enum fixed_addresses { FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, #endif + /* + * FIX_IOREMAP entries are useful for mapping physical address + * space before ioremap() is useable, e.g. really early in boot + * before kmalloc() is working. + */ +#define FIX_N_IOREMAPS 32 + FIX_IOREMAP_BEGIN, + FIX_IOREMAP_END = FIX_IOREMAP_BEGIN + FIX_N_IOREMAPS, __end_of_fixed_addresses }; diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h index 0cf2a57..1f11da7 100644 --- a/arch/sh/include/asm/io.h +++ b/arch/sh/include/asm/io.h @@ -294,6 +294,10 @@ __ioremap_mode(unsigned long offset, unsigned long size, unsigned long flags) #define iounmap(addr) \ __iounmap((addr)) +extern void __iomem *ioremap_fixed(resource_size_t, unsigned long, pgprot_t); +extern void iounmap_fixed(void __iomem *); +extern void ioremap_fixed_init(void); + #define maybebadio(port) \ printk(KERN_ERR "bad PC-like io %s:%u for port 0x%lx at 0x%08x\n", \ __func__, __LINE__, (port), (u32)__builtin_return_address(0)) diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c index 5a947a2..c84a525 100644 --- a/arch/sh/kernel/setup.c +++ b/arch/sh/kernel/setup.c @@ -443,6 +443,8 @@ void __init setup_arch(char **cmdline_p) setup_memory(); sparse_init(); + ioremap_fixed_init(); + #ifdef CONFIG_DUMMY_CONSOLE conswitchp = &dummy_con; #endif diff --git a/arch/sh/mm/Makefile b/arch/sh/mm/Makefile index 8a70535..f554730 100644 --- a/arch/sh/mm/Makefile +++ b/arch/sh/mm/Makefile @@ -15,7 +15,8 @@ obj-y += $(cacheops-y) mmu-y := nommu.o extable_32.o mmu-$(CONFIG_MMU) := extable_$(BITS).o fault_$(BITS).o \ - ioremap_$(BITS).o kmap.o tlbflush_$(BITS).o + ioremap_$(BITS).o ioremap_fixed.o kmap.o \ + tlbflush_$(BITS).o obj-y += $(mmu-y) obj-$(CONFIG_DEBUG_FS) += asids-debugfs.o diff --git a/arch/sh/mm/ioremap_fixed.c b/arch/sh/mm/ioremap_fixed.c new file mode 100644 index 0000000..235aeef --- /dev/null +++ b/arch/sh/mm/ioremap_fixed.c @@ -0,0 +1,209 @@ +/* + * Re-map IO memory to kernel address space so that we can access it. + * + * These functions should only be used when it is necessary to map a + * physical address space into the kernel address space before ioremap() + * can be used, e.g. early in boot before paging_init(). + * + * Copyright (C) 2009 Matt Fleming + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct ioremap_map { + void __iomem *addr; + unsigned long size; + unsigned long fixmap_addr; +}; + +static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS]; +static pte_t *fixed_pte; + +static inline pmd_t *__ioremap_fixed_pmd(unsigned long addr) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset_k(addr); + if (pgd_none(*pgd)) { + pgd_ERROR(*pgd); + return NULL; + } + + pud = pud_offset(pgd, addr); + if (pud_none(*pud) || pud_bad(*pud)) + return NULL; + + /* + * We expected 'pmd' to be empty because we're going to hook up + * 'fixed_pte' into this pmd. + */ + pmd = pmd_offset(pud, addr); + if (!pmd_none(*pmd) || pmd_bad(*pmd)) + return NULL; + + return pmd; +} + +static void +__ioremap_set_fixmap(enum fixed_addresses idx, unsigned long phys, + pgprot_t prot, int load) +{ + unsigned long addr; + pte_t *pte; + + if (idx < FIX_IOREMAP_BEGIN || idx >= FIX_IOREMAP_END) + return; + + addr = __fix_to_virt(idx); + pte = &fixed_pte[pte_index(addr)]; + + set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot)); + local_flush_tlb_one(get_asid(), addr); + + if (load) { + /* + * per_cpu_trap_init() hasn't been called yet so we + * haven't initialised VBR and can't fixup a data TLB + * miss in software. We have to preload the TLB with the + * mapping. + */ + __update_tlb(NULL, addr, *pte); + } +} + +void __init ioremap_fixed_init(void) +{ + struct ioremap_map *map; + unsigned long addr; + pmd_t *pmd; + int i; + + addr = __fix_to_virt(FIX_IOREMAP_BEGIN); + pmd = __ioremap_fixed_pmd(addr); + + if (!pmd) { + printk(KERN_ERR "%s: Page tables in unexpected state\n", + __func__); + return; + } + + fixed_pte = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE); + pmd_populate_kernel(&init_mm, pmd, fixed_pte); + + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i); + } +} + +void __init __iomem * +ioremap_fixed(resource_size_t phys_addr, unsigned long size, pgprot_t prot) +{ + enum fixed_addresses idx0, idx; + resource_size_t last_addr; + struct ioremap_map *map; + unsigned long offset; + unsigned int nrpages; + int i, slot; + + slot = -1; + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + if (!map->addr) { + map->size = size; + slot = i; + break; + } + } + + if (slot < 0) + return NULL; + + /* Don't allow wraparound or zero size */ + last_addr = phys_addr + size - 1; + if (!size || last_addr < phys_addr) + return NULL; + + /* + * Fixmap mappings have to be page-aligned + */ + offset = phys_addr & ~PAGE_MASK; + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(last_addr + 1) - phys_addr; + + /* + * Mappings have to fit in the FIX_IOREMAP area. + */ + nrpages = size >> PAGE_SHIFT; + if (nrpages > FIX_N_IOREMAPS) + return NULL; + + /* + * Ok, go for it.. + */ + idx0 = FIX_IOREMAP_BEGIN + slot; + idx = idx0; + while (nrpages > 0) { + __ioremap_set_fixmap(idx, phys_addr, prot, 1); + phys_addr += PAGE_SIZE; + idx++; + --nrpages; + } + + map->addr = (void __iomem *)(offset + map->fixmap_addr); + return map->addr; +} + +void __init iounmap_fixed(void __iomem *addr) +{ + enum fixed_addresses idx; + unsigned long virt_addr; + struct ioremap_map *map; + unsigned long offset; + unsigned int nrpages; + int i, slot; + + slot = -1; + for (i = 0; i < FIX_N_IOREMAPS; i++) { + map = &ioremap_maps[i]; + if (map->addr == addr) { + slot = i; + break; + } + } + + if (slot < 0) + return; + + virt_addr = (unsigned long)addr; + + offset = virt_addr & ~PAGE_MASK; + nrpages = PAGE_ALIGN(offset + map->size - 1) >> PAGE_SHIFT; + + idx = FIX_IOREMAP_BEGIN + slot; + while (nrpages > 0) { + __ioremap_set_fixmap(idx, 0, __pgprot(0), 0); + idx++; + --nrpages; + } + + map->size = 0; + map->addr = NULL; +}