From c2794437091a4fda72c4a4f3567dd728dcc0c3c9 Mon Sep 17 00:00:00 2001
From: Rob Herring <rob.herring@calxeda.com>
Date: Wed, 29 Feb 2012 18:10:58 -0600
Subject: ARM: Add fixed PCI i/o mapping
This adds a fixed virtual mapping for PCI i/o addresses. The mapping is
located at the last 2MB of vmalloc region (0xfee00000-0xff000000). 2MB
is used to align with PMD size, but IO_SPACE_LIMIT is 1MB. The space
is reserved after .map_io and can be mapped at any time later with
pci_ioremap_io. Platforms which need early i/o mapping (e.g. for vga
console) can call pci_map_io_early in their .map_io function.
This has changed completely from the 1st implementation which only
supported creating the static mapping at .map_io.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
---
arch/arm/include/asm/io.h | 8 ++++++
arch/arm/include/asm/mach/map.h | 8 ++++++
arch/arm/include/asm/mach/pci.h | 10 ++++++++
arch/arm/kernel/bios32.c | 13 ++++++++++
arch/arm/mm/ioremap.c | 14 +++++++++++
arch/arm/mm/mmu.c | 54 ++++++++++++++++++++++++++++++++---------
6 files changed, 96 insertions(+), 11 deletions(-)
(limited to 'arch')
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 815c669fec0a..8f4db67533e5 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -113,11 +113,19 @@ static inline void __iomem *__typesafe_io(unsigned long addr)
#define __iowmb() do { } while (0)
#endif
+/* PCI fixed i/o mapping */
+#define PCI_IO_VIRT_BASE 0xfee00000
+
+extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
+
/*
* Now, pick up the machine-defined IO definitions
*/
#ifdef CONFIG_NEED_MACH_IO_H
#include <mach/io.h>
+#elif defined(CONFIG_PCI)
+#define IO_SPACE_LIMIT ((resource_size_t)0xfffff)
+#define __io(a) __typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
#else
#define __io(a) __typesafe_io((a) & IO_SPACE_LIMIT)
#endif
diff --git a/arch/arm/include/asm/mach/map.h b/arch/arm/include/asm/mach/map.h
index a6efcdd6fd25..195ac2f9d3d3 100644
--- a/arch/arm/include/asm/mach/map.h
+++ b/arch/arm/include/asm/mach/map.h
@@ -9,6 +9,9 @@
*
* Page table mapping constructs and function prototypes
*/
+#ifndef __ASM_MACH_MAP_H
+#define __ASM_MACH_MAP_H
+
#include <asm/io.h>
struct map_desc {
@@ -34,6 +37,8 @@ struct map_desc {
#ifdef CONFIG_MMU
extern void iotable_init(struct map_desc *, int);
+extern void vm_reserve_area_early(unsigned long addr, unsigned long size,
+ void *caller);
struct mem_type;
extern const struct mem_type *get_mem_type(unsigned int type);
@@ -44,4 +49,7 @@ extern int ioremap_page(unsigned long virt, unsigned long phys,
const struct mem_type *mtype);
#else
#define iotable_init(map,num) do { } while (0)
+#define vm_reserve_area_early(a,s,c) do { } while (0)
+#endif
+
#endif
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 26c511fddf8f..df818876fa31 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h
@@ -11,6 +11,7 @@
#ifndef __ASM_MACH_PCI_H
#define __ASM_MACH_PCI_H
+
struct pci_sys_data;
struct pci_ops;
struct pci_bus;
@@ -54,6 +55,15 @@ struct pci_sys_data {
*/
void pci_common_init(struct hw_pci *);
+/*
+ * Setup early fixed I/O mapping.
+ */
+#if defined(CONFIG_PCI)
+extern void pci_map_io_early(unsigned long pfn);
+#else
+static inline void pci_map_io_early(unsigned long pfn) {}
+#endif
+
/*
* PCI controllers
*/
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 25552508c3fd..c3165f0fef63 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -13,6 +13,7 @@
#include <linux/io.h>
#include <asm/mach-types.h>
+#include <asm/mach/map.h>
#include <asm/mach/pci.h>
static int debug_pci;
@@ -627,3 +628,15 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
return 0;
}
+
+void __init pci_map_io_early(unsigned long pfn)
+{
+ struct map_desc pci_io_desc = {
+ .virtual = PCI_IO_VIRT_BASE,
+ .type = MT_DEVICE,
+ .length = SZ_64K,
+ };
+
+ pci_io_desc.pfn = pfn;
+ iotable_init(&pci_io_desc, 1);
+}
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 4f55f5062ab7..8727802f8661 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -36,6 +36,7 @@
#include <asm/system_info.h>
#include <asm/mach/map.h>
+#include <asm/mach/pci.h>
#include "mm.h"
int ioremap_page(unsigned long virt, unsigned long phys,
@@ -383,3 +384,16 @@ void __arm_iounmap(volatile void __iomem *io_addr)
arch_iounmap(io_addr);
}
EXPORT_SYMBOL(__arm_iounmap);
+
+#ifdef CONFIG_PCI
+int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr)
+{
+ BUG_ON(offset + SZ_64K > IO_SPACE_LIMIT);
+
+ return ioremap_page_range(PCI_IO_VIRT_BASE + offset,
+ PCI_IO_VIRT_BASE + offset + SZ_64K,
+ phys_addr,
+ __pgprot(get_mem_type(MT_DEVICE)->prot_pte));
+}
+EXPORT_SYMBOL_GPL(pci_ioremap_io);
+#endif
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index cf4528d51774..714a7fd99ca3 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -31,6 +31,7 @@
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
+#include <asm/mach/pci.h>
#include "mm.h"
@@ -216,7 +217,7 @@ static struct mem_type mem_types[] = {
.prot_l1 = PMD_TYPE_TABLE,
.prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
.domain = DOMAIN_IO,
- },
+ },
[MT_DEVICE_WC] = { /* ioremap_wc */
.prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
.prot_l1 = PMD_TYPE_TABLE,
@@ -783,14 +784,27 @@ void __init iotable_init(struct map_desc *io_desc, int nr)
create_mapping(md);
vm->addr = (void *)(md->virtual & PAGE_MASK);
vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
- vm->phys_addr = __pfn_to_phys(md->pfn);
- vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
+ vm->phys_addr = __pfn_to_phys(md->pfn);
+ vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
vm->flags |= VM_ARM_MTYPE(md->type);
vm->caller = iotable_init;
vm_area_add_early(vm++);
}
}
+void __init vm_reserve_area_early(unsigned long addr, unsigned long size,
+ void *caller)
+{
+ struct vm_struct *vm;
+
+ vm = early_alloc_aligned(sizeof(*vm), __alignof__(*vm));
+ vm->addr = (void *)addr;
+ vm->size = size;
+ vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
+ vm->caller = caller;
+ vm_area_add_early(vm);
+}
+
#ifndef CONFIG_ARM_LPAE
/*
@@ -808,14 +822,7 @@ void __init iotable_init(struct map_desc *io_desc, int nr)
static void __init pmd_empty_section_gap(unsigned long addr)
{
- struct vm_struct *vm;
-
- vm = early_alloc_aligned(sizeof(*vm), __alignof__(*vm));
- vm->addr = (void *)addr;
- vm->size = SECTION_SIZE;
- vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
- vm->caller = pmd_empty_section_gap;
- vm_area_add_early(vm);
+ vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap);
}
static void __init fill_pmd_gaps(void)
@@ -864,6 +871,28 @@ static void __init fill_pmd_gaps(void)
#define fill_pmd_gaps() do { } while (0)
#endif
+#if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H)
+static void __init pci_reserve_io(void)
+{
+ struct vm_struct *vm;
+ unsigned long addr;
+
+ /* we're still single threaded hence no lock needed here */
+ for (vm = vmlist; vm; vm = vm->next) {
+ if (!(vm->flags & VM_ARM_STATIC_MAPPING))
+ continue;
+ addr = (unsigned long)vm->addr;
+ addr &= ~(SZ_2M - 1);
+ if (addr == PCI_IO_VIRT_BASE)
+ return;
+
+ }
+ vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io);
+}
+#else
+#define pci_reserve_io() do { } while (0)
+#endif
+
static void * __initdata vmalloc_min =
(void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
@@ -1147,6 +1176,9 @@ static void __init devicemaps_init(struct machine_desc *mdesc)
mdesc->map_io();
fill_pmd_gaps();
+ /* Reserve fixed i/o space in VMALLOC region */
+ pci_reserve_io();
+
/*
* Finally flush the caches and tlb to ensure that we're in a
* consistent state wrt the writebuffer. This also ensures that
--
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