diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index cd8b6e657b94f1da63e88237b1a6690a9fbbb272..2f45877a539d2694021770781ee137de9d882ab7 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -309,6 +309,7 @@ IOMAP
devm_ioremap()
devm_ioremap_uc()
devm_ioremap_wc()
+ devm_ioremap_np()
devm_ioremap_resource() : checks resource, requests memory region, ioremaps
devm_ioremap_resource_wc()
devm_platform_ioremap_resource() : calls devm_ioremap_resource() for platform device
diff --git a/arch/sparc/include/asm/io_64.h b/arch/sparc/include/asm/io_64.h
index 9bb27e5c22f159c97fed8410d59dd92c91084e0e..9fbfc9574432aadace3149cd6fafea8eeaedd5a8 100644
--- a/arch/sparc/include/asm/io_64.h
+++ b/arch/sparc/include/asm/io_64.h
@@ -409,6 +409,10 @@ static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
#define ioremap_uc(X,Y) ioremap((X),(Y))
#define ioremap_wc(X,Y) ioremap((X),(Y))
#define ioremap_wt(X,Y) ioremap((X),(Y))
+static inline void __iomem *ioremap_np(unsigned long offset, unsigned long size)
+{
+ return NULL;
+}
static inline void iounmap(volatile void __iomem *addr)
{
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index c6af40ce03befec1740fd9ab705648e1eba2bf81..082e0c96db6e1b12788f3521d7c84acc04f3bffc 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -942,7 +942,9 @@ static inline void *phys_to_virt(unsigned long address)
*
* ioremap_wc() and ioremap_wt() can provide more relaxed caching attributes
* for specific drivers if the architecture choses to implement them. If they
- * are not implemented we fall back to plain ioremap.
+ * are not implemented we fall back to plain ioremap. Conversely, ioremap_np()
+ * can provide stricter non-posted write semantics if the architecture
+ * implements them.
*/
#ifndef CONFIG_MMU
#ifndef ioremap
@@ -993,6 +995,24 @@ static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size)
{
return NULL;
}
+
+/*
+ * ioremap_np needs an explicit architecture implementation, as it
+ * requests stronger semantics than regular ioremap(). Portable drivers
+ * should instead use one of the higher-level abstractions, like
+ * devm_ioremap_resource(), to choose the correct variant for any given
+ * device and bus. Portable drivers with a good reason to want non-posted
+ * write semantics should always provide an ioremap() fallback in case
+ * ioremap_np() is not available.
+ */
+#ifndef ioremap_np
+#define ioremap_np ioremap_np
+static inline void __iomem *ioremap_np(phys_addr_t offset, size_t size)
+{
+ return NULL;
+}
+#endif
+
#endif
#ifdef CONFIG_HAS_IOPORT_MAP
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index 6492246649693bdfce927be48bdf700890588121..9b3eb6d86200180d1fe6ff40687c807bb6107bc4 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -101,6 +101,15 @@ extern void ioport_unmap(void __iomem *);
#define ioremap_wt ioremap
#endif
+#ifndef ARCH_HAS_IOREMAP_NP
+/* See the comment in asm-generic/io.h about ioremap_np(). */
+#define ioremap_np ioremap_np
+static inline void __iomem *ioremap_np(phys_addr_t offset, size_t size)
+{
+ return NULL;
+}
+#endif
+
#ifdef CONFIG_PCI
/* Destroy a virtual mapping cookie for a PCI BAR (memory or IO) */
struct pci_dev;
diff --git a/include/linux/io.h b/include/linux/io.h
index 8394c56babc26fa1a4d99cd75126cf6ca2a26b42..d718354ed3e16d33e1d7cac56e7bbac49f07e438 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -68,6 +68,8 @@ void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
resource_size_t size);
void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
resource_size_t size);
+void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset,
+ resource_size_t size);
void devm_iounmap(struct device *dev, void __iomem *addr);
int check_signature(const volatile void __iomem *io_addr,
const unsigned char *signature, int length);
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 55de385c839cf5648bffc689b2b1aa4253c74f08..1de6c2e40c3248a0cee3e239b4178012b9b21a7b 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -108,6 +108,7 @@ struct resource {
#define IORESOURCE_MEM_32BIT (3<<3)
#define IORESOURCE_MEM_SHADOWABLE (1<<5) /* dup: IORESOURCE_SHADOWABLE */
#define IORESOURCE_MEM_EXPANSIONROM (1<<6)
+#define IORESOURCE_MEM_NONPOSTED (1<<7)
/* PnP I/O specific bits (IORESOURCE_BITS) */
#define IORESOURCE_IO_16BIT_ADDR (1<<0)
diff --git a/lib/devres.c b/lib/devres.c
index 2a4ff5d6428860b79ed04001acb87137b6dbc651..4679dbb1bf5f8a82ce3773ad14a5f0e0343aaf8b 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -10,6 +10,7 @@ enum devm_ioremap_type {
DEVM_IOREMAP = 0,
DEVM_IOREMAP_UC,
DEVM_IOREMAP_WC,
+ DEVM_IOREMAP_NP,
};
void devm_ioremap_release(struct device *dev, void *res)
@@ -42,6 +43,9 @@ static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
case DEVM_IOREMAP_WC:
addr = ioremap_wc(offset, size);
break;
+ case DEVM_IOREMAP_NP:
+ addr = ioremap_np(offset, size);
+ break;
}
if (addr) {
@@ -98,6 +102,21 @@ void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
}
EXPORT_SYMBOL(devm_ioremap_wc);
+/**
+ * devm_ioremap_np - Managed ioremap_np()
+ * @dev: Generic device to remap IO address for
+ * @offset: Resource address to map
+ * @size: Size of map
+ *
+ * Managed ioremap_np(). Map is automatically unmapped on driver detach.
+ */
+void __iomem *devm_ioremap_np(struct device *dev, resource_size_t offset,
+ resource_size_t size)
+{
+ return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_NP);
+}
+EXPORT_SYMBOL(devm_ioremap_np);
+
/**
* devm_iounmap - Managed iounmap()
* @dev: Generic device to unmap for
@@ -128,6 +147,9 @@ __devm_ioremap_resource(struct device *dev, const struct resource *res,
return IOMEM_ERR_PTR(-EINVAL);
}
+ if (type == DEVM_IOREMAP && res->flags & IORESOURCE_MEM_NONPOSTED)
+ type = DEVM_IOREMAP_NP;
+
size = resource_size(res);
if (res->name)