From: venkatesh.pallipadi@intel.com
To: ak@muc.de, ebiederm@xmission.com, rdreier@cisco.com,
torvalds@linux-foundation.org, gregkh@suse.de, airlied@skynet.ie,
davej@redhat.com, mingo@elte.hu, tglx@linutronix.de,
hpa@zytor.com, akpm@linux-foundation.org, arjan@infradead.org,
jesse.barnes@intel.com
Cc: linux-kernel@vger.kernel.org,
Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
Suresh Siddha <suresh.b.siddha@intel.com>
Subject: [patch 12/13] x86: PAT Add ioremap_wc() interface
Date: Tue, 18 Mar 2008 17:00:24 -0700 [thread overview]
Message-ID: <20080319000100.773690000@intel.com> (raw)
In-Reply-To: 20080319000012.439150000@intel.com
[-- Attachment #1: ioremap_wc.patch --]
[-- Type: text/plain, Size: 4942 bytes --]
Introduce ioremap_wc for wc remap. There is also a generic ioremap_wc
aliased to ioremap_uc so that drivers can use this interface transparently.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Index: linux-2.6-x86.git/arch/x86/mm/ioremap.c
===================================================================
--- linux-2.6-x86.git.orig/arch/x86/mm/ioremap.c 2008-03-18 03:21:25.000000000 -0700
+++ linux-2.6-x86.git/arch/x86/mm/ioremap.c 2008-03-18 09:20:21.000000000 -0700
@@ -98,6 +98,9 @@
default:
err = _set_memory_uc(vaddr, nrpages);
break;
+ case _PAGE_CACHE_WC:
+ err = _set_memory_wc(vaddr, nrpages);
+ break;
case _PAGE_CACHE_WB:
err = _set_memory_wb(vaddr, nrpages);
break;
@@ -168,8 +171,13 @@
* Do not fallback to certain memory types with certain
* requested type:
* - request is uncached, return cannot be write-back
+ * - request is uncached, return cannot be write-combine
+ * - request is write-combine, return cannot be write-back
*/
if ((prot_val == _PAGE_CACHE_UC &&
+ (new_prot_val == _PAGE_CACHE_WB ||
+ new_prot_val == _PAGE_CACHE_WC)) ||
+ (prot_val == _PAGE_CACHE_WC &&
new_prot_val == _PAGE_CACHE_WB)) {
free_memtype(phys_addr, phys_addr + size);
return NULL;
@@ -182,6 +190,9 @@
default:
prot = PAGE_KERNEL_NOCACHE;
break;
+ case _PAGE_CACHE_WC:
+ prot = PAGE_KERNEL_WC;
+ break;
case _PAGE_CACHE_WB:
prot = PAGE_KERNEL;
break;
@@ -240,6 +251,25 @@
}
EXPORT_SYMBOL(ioremap_nocache);
+/**
+ * ioremap_wc - map memory into CPU space write combined
+ * @offset: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * This version of ioremap ensures that the memory is marked write combining.
+ * Write combining allows faster writes to some hardware devices.
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_wc(unsigned long phys_addr, unsigned long size)
+{
+ if (pat_wc_enabled)
+ return __ioremap(phys_addr, size, _PAGE_CACHE_WC);
+ else
+ return ioremap_nocache(phys_addr, size);
+}
+EXPORT_SYMBOL(ioremap_wc);
+
void __iomem *ioremap_cache(unsigned long phys_addr, unsigned long size)
{
return __ioremap(phys_addr, size, _PAGE_CACHE_WB);
Index: linux-2.6-x86.git/include/asm-generic/iomap.h
===================================================================
--- linux-2.6-x86.git.orig/include/asm-generic/iomap.h 2008-03-18 02:16:03.000000000 -0700
+++ linux-2.6-x86.git/include/asm-generic/iomap.h 2008-03-18 03:54:39.000000000 -0700
@@ -60,6 +60,10 @@
extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
extern void ioport_unmap(void __iomem *);
+#ifndef ARCH_HAS_IOREMAP_WC
+#define ioremap_wc ioremap_nocache
+#endif
+
/* Create a virtual mapping cookie for a PCI BAR (memory or IO) */
struct pci_dev;
extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max);
Index: linux-2.6-x86.git/include/asm-x86/io.h
===================================================================
--- linux-2.6-x86.git.orig/include/asm-x86/io.h 2008-03-18 03:14:09.000000000 -0700
+++ linux-2.6-x86.git/include/asm-x86/io.h 2008-03-18 03:54:39.000000000 -0700
@@ -1,6 +1,8 @@
#ifndef _ASM_X86_IO_H
#define _ASM_X86_IO_H
+#define ARCH_HAS_IOREMAP_WC
+
#ifdef CONFIG_X86_32
# include "io_32.h"
#else
@@ -9,6 +11,7 @@
extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
unsigned long prot_val);
+extern void __iomem * ioremap_wc(unsigned long offset, unsigned long size);
extern void *xlate_dev_mem_ptr(unsigned long phys);
extern void unxlate_dev_mem_ptr(unsigned long phys, void *addr);
Index: linux-2.6-x86.git/include/asm-x86/pgtable.h
===================================================================
--- linux-2.6-x86.git.orig/include/asm-x86/pgtable.h 2008-03-18 03:33:01.000000000 -0700
+++ linux-2.6-x86.git/include/asm-x86/pgtable.h 2008-03-18 03:54:39.000000000 -0700
@@ -90,6 +90,7 @@
#define __PAGE_KERNEL_RO (__PAGE_KERNEL & ~_PAGE_RW)
#define __PAGE_KERNEL_RX (__PAGE_KERNEL_EXEC & ~_PAGE_RW)
#define __PAGE_KERNEL_EXEC_NOCACHE (__PAGE_KERNEL_EXEC | _PAGE_PCD | _PAGE_PWT)
+#define __PAGE_KERNEL_WC (__PAGE_KERNEL | _PAGE_CACHE_WC)
#define __PAGE_KERNEL_NOCACHE (__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
#define __PAGE_KERNEL_VSYSCALL (__PAGE_KERNEL_RX | _PAGE_USER)
#define __PAGE_KERNEL_VSYSCALL_NOCACHE (__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
@@ -106,6 +107,7 @@
#define PAGE_KERNEL_RO MAKE_GLOBAL(__PAGE_KERNEL_RO)
#define PAGE_KERNEL_EXEC MAKE_GLOBAL(__PAGE_KERNEL_EXEC)
#define PAGE_KERNEL_RX MAKE_GLOBAL(__PAGE_KERNEL_RX)
+#define PAGE_KERNEL_WC MAKE_GLOBAL(__PAGE_KERNEL_WC)
#define PAGE_KERNEL_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
#define PAGE_KERNEL_EXEC_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_EXEC_NOCACHE)
#define PAGE_KERNEL_LARGE MAKE_GLOBAL(__PAGE_KERNEL_LARGE)
--
next prev parent reply other threads:[~2008-03-19 20:28 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-19 0:00 [patch 00/13] x86: PAT support updated - v3 venkatesh.pallipadi
2008-03-19 0:00 ` [patch 01/13] x86: PAT documentation venkatesh.pallipadi
2008-03-19 0:00 ` [patch 02/13] x86: PAT infrastructure patch venkatesh.pallipadi
2008-03-19 20:06 ` Randy Dunlap
2008-03-24 21:22 ` Venki Pallipadi
2008-03-19 0:00 ` [patch 03/13] x86: PAT Avoid aliasing in /dev/mem read/write venkatesh.pallipadi
2008-03-19 0:00 ` [patch 04/13] x86: PAT make ioremap_change_attr non-static venkatesh.pallipadi
2008-03-19 0:00 ` [patch 05/13] x86: PAT use reserve free memtype in ioremap and iounmap venkatesh.pallipadi
2008-03-19 0:00 ` [patch 06/13] x86: PAT use reserve free memtype in set_memory_uc venkatesh.pallipadi
2008-03-19 0:00 ` [patch 07/13] x86: PAT use reserve free memtype in pci_mmap_page_range venkatesh.pallipadi
2008-03-19 0:00 ` [patch 08/13] x86: PAT phys_mem_access_prot_allowed for dev/mem mmap venkatesh.pallipadi
2008-03-19 0:00 ` [patch 09/13] x86: PAT use reserve free memtype in mmap of /dev/mem venkatesh.pallipadi
2008-03-19 0:00 ` [patch 10/13] x86: PAT export resource_wc in pci sysfs venkatesh.pallipadi
2008-03-19 0:00 ` [patch 11/13] x86: PAT Add set_memory_wc() interface venkatesh.pallipadi
2008-03-19 0:00 ` venkatesh.pallipadi [this message]
2008-03-19 0:00 ` [patch 13/13] x86: PAT Patch to add PAT related debug prints venkatesh.pallipadi
2008-03-21 13:24 ` [patch 00/13] x86: PAT support updated - v3 Ingo Molnar
2008-03-21 14:55 ` Ingo Molnar
2008-03-21 19:26 ` Venki Pallipadi
2008-03-21 13:29 ` H. Peter Anvin
2008-03-21 19:19 ` Venki Pallipadi
2008-03-21 19:59 ` H. Peter Anvin
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