From: Toshi Kani <toshi.kani@hp.com>
To: bp@alien8.de, hpa@zytor.com, tglx@linutronix.de,
mingo@redhat.com, akpm@linux-foundation.org, arnd@arndb.de
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, x86@kernel.org,
linux-nvdimm@lists.01.org, jgross@suse.com,
stefan.bader@canonical.com, luto@amacapital.net, hmh@hmh.eng.br,
yigal@plexistor.com, konrad.wilk@oracle.com, Elliott@hp.com,
mcgrof@suse.com, hch@lst.de, Toshi Kani <toshi.kani@hp.com>
Subject: [PATCH v11 6/12] x86, mm, asm-gen: Add ioremap_wt() for WT
Date: Fri, 29 May 2015 16:59:04 -0600 [thread overview]
Message-ID: <1432940350-1802-7-git-send-email-toshi.kani@hp.com> (raw)
In-Reply-To: <1432940350-1802-1-git-send-email-toshi.kani@hp.com>
From: Toshi Kani <toshi.kani@hp.com>
This patch adds ioremap_wt() for creating WT mapping on x86.
It follows the same model as ioremap_wc() for multi-architecture
support. ARCH_HAS_IOREMAP_WT is defined in the x86 version of
io.h to indicate that ioremap_wt() is implemented on x86.
Also update the PAT documentation file to cover ioremap_wt().
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/x86/pat.txt | 4 +++-
arch/x86/include/asm/io.h | 2 ++
arch/x86/mm/ioremap.c | 21 +++++++++++++++++++++
include/asm-generic/io.h | 9 +++++++++
include/asm-generic/iomap.h | 4 ++++
5 files changed, 39 insertions(+), 1 deletion(-)
diff --git a/Documentation/x86/pat.txt b/Documentation/x86/pat.txt
index 521bd8a..db0de6c 100644
--- a/Documentation/x86/pat.txt
+++ b/Documentation/x86/pat.txt
@@ -12,7 +12,7 @@ virtual addresses.
PAT allows for different types of memory attributes. The most commonly used
ones that will be supported at this time are Write-back, Uncached,
-Write-combined and Uncached Minus.
+Write-combined, Write-through and Uncached Minus.
PAT APIs
@@ -40,6 +40,8 @@ ioremap_nocache | -- | UC- | UC- |
| | | |
ioremap_wc | -- | -- | WC |
| | | |
+ioremap_wt | -- | -- | WT |
+ | | | |
set_memory_uc | UC- | -- | -- |
set_memory_wb | | | |
| | | |
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index a2b9740..6c3a130 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -35,6 +35,7 @@
*/
#define ARCH_HAS_IOREMAP_WC
+#define ARCH_HAS_IOREMAP_WT
#include <linux/string.h>
#include <linux/compiler.h>
@@ -321,6 +322,7 @@ extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
enum page_cache_mode pcm);
extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
+extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
extern bool is_early_ioremap_ptep(pte_t *ptep);
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 078c270..779b1a2 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -172,6 +172,10 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
prot = __pgprot(pgprot_val(prot) |
cachemode2protval(_PAGE_CACHE_MODE_WC));
break;
+ case _PAGE_CACHE_MODE_WT:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WT));
+ break;
case _PAGE_CACHE_MODE_WB:
break;
}
@@ -297,6 +301,23 @@ void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
}
EXPORT_SYMBOL(ioremap_wc);
+/**
+ * ioremap_wt - map memory into CPU space write through
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * This version of ioremap ensures that the memory is marked write through.
+ * Write through stores data into memory while keeping the cache up-to-date.
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wt);
+
void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
{
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 90ccba7..f56094c 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -785,8 +785,17 @@ static inline void __iomem *ioremap_wc(phys_addr_t offset, size_t size)
}
#endif
+#ifndef ioremap_wt
+#define ioremap_wt ioremap_wt
+static inline void __iomem *ioremap_wt(phys_addr_t offset, size_t size)
+{
+ return ioremap_nocache(offset, size);
+}
+#endif
+
#ifndef iounmap
#define iounmap iounmap
+
static inline void iounmap(void __iomem *addr)
{
}
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index 1b41011..d8f8622 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -66,6 +66,10 @@ extern void ioport_unmap(void __iomem *);
#define ioremap_wc ioremap_nocache
#endif
+#ifndef ARCH_HAS_IOREMAP_WT
+#define ioremap_wt ioremap_nocache
+#endif
+
#ifdef CONFIG_PCI
/* Destroy a virtual mapping cookie for a PCI BAR (memory or IO) */
struct pci_dev;
--
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next prev parent reply other threads:[~2015-05-29 23:19 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-29 22:58 [PATCH v11 0/12] Support Write-Through mapping on x86 Toshi Kani
2015-05-29 22:58 ` [PATCH v11 1/12] x86, mm, pat: Cleanup init flags in pat_init() Toshi Kani
2015-05-29 22:59 ` [PATCH v11 2/12] x86, mm, pat: Refactor !pat_enabled handling Toshi Kani
2015-05-31 9:46 ` Borislav Petkov
2015-05-31 9:48 ` [PATCH 1/4] x86/pat: Untangle pat_init() Borislav Petkov
2015-05-31 9:48 ` [PATCH 2/4] x86/pat: Merge pat_init_cache_modes() into its caller Borislav Petkov
2015-05-31 10:15 ` Juergen Gross
2015-05-31 10:24 ` Borislav Petkov
2015-05-31 10:23 ` Borislav Petkov
2015-05-31 11:02 ` Juergen Gross
2015-06-01 18:15 ` Toshi Kani
2015-05-31 9:48 ` [PATCH 3/4] x86/pat: Emulate PAT when it is disabled Borislav Petkov
2015-05-31 9:48 ` [PATCH 4/4] x86/pat: Remove pat_enabled() checks Borislav Petkov
2015-06-01 18:26 ` Toshi Kani
2015-06-01 18:51 ` Borislav Petkov
2015-06-01 16:17 ` [PATCH 1/4] x86/pat: Untangle pat_init() Toshi Kani
2015-06-01 15:50 ` [PATCH v11 2/12] x86, mm, pat: Refactor !pat_enabled handling Toshi Kani
2015-05-29 22:59 ` [PATCH v11 3/12] x86, mm, pat: Set WT to PA7 slot of PAT MSR Toshi Kani
2015-05-29 22:59 ` [PATCH v11 4/12] x86, mm, pat: Change reserve_memtype() for WT Toshi Kani
2015-05-29 22:59 ` [PATCH v11 5/12] x86, asm: Change is_new_memtype_allowed() " Toshi Kani
2015-05-29 22:59 ` Toshi Kani [this message]
2015-05-30 9:18 ` [PATCH v11 6/12] x86, mm, asm-gen: Add ioremap_wt() " Geert Uytterhoeven
2015-05-31 0:58 ` Toshi Kani
2015-05-29 22:59 ` [PATCH v11 7/12] arch/*/asm/io.h: Add ioremap_wt() to all architectures Toshi Kani
2015-05-29 22:59 ` [PATCH v11 8/12] video/fbdev, asm/io.h: Remove ioremap_writethrough() Toshi Kani
2015-05-29 22:59 ` [PATCH v11 9/12] x86, mm, pat: Add pgprot_writethrough() for WT Toshi Kani
2015-05-29 22:59 ` [PATCH v11 10/12] x86, mm, asm: Add WT support to set_page_memtype() Toshi Kani
2015-05-29 22:59 ` [PATCH v11 11/12] x86, mm: Add set_memory_wt() for WT Toshi Kani
2015-05-29 22:59 ` [PATCH v11 12/12] drivers/block/pmem: Map NVDIMM with ioremap_wt() Toshi Kani
2015-05-30 1:18 ` Dan Williams
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