[PATCH v3 08/32] cris: include default ioremap_nopost() implementation

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From	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Newsgroups	linux.kernel
Subject	[PATCH v3 08/32] cris: include default ioremap_nopost() implementation
Date	Tue, 11 Apr 2017 14:40:03 +0200
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The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and Posting")
mandate non-posted configuration transactions. As further highlighted in
the PCIe specifications (4.0 - Rev0.3, "Ordering Considerations for the
Enhanced Configuration Access Mechanism"), through ECAM and
ECAM-derivative configuration mechanism, the memory mapped transactions
from the host CPU into Configuration Requests on the PCI express fabric
may create ordering problems for software because writes to memory
address are typically posted transactions (unless the architecture can
enforce through virtual address mapping non-posted write transactions
behaviour) but writes to Configuration Space are not posted on the PCI
express fabric.

Include the asm-generic ioremap_nopost() implementation (currently
falling back to ioremap_nocache()) to provide a non-posted writes
ioremap interface to kernel subsystems.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Niklas Cassel <nks@flawful.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <starvik@axis.com>
---
 arch/cris/include/asm/io.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/cris/include/asm/io.h b/arch/cris/include/asm/io.h
index fe0b2a0..b9c9397 100644
--- a/arch/cris/include/asm/io.h
+++ b/arch/cris/include/asm/io.h
@@ -21,5 +21,6 @@ extern void iounmap(volatile void * __iomem addr);
 extern void __iomem * ioremap_nocache(unsigned long offset, unsigned long size);
 
 #include <asm-generic/io.h>
+#include <asm-generic/ioremap-nopost.h>
 
 #endif
-- 
2.10.0

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[PATCH v3 08/32] cris: include default ioremap_nopost() implementation Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2017-04-11 14:40 +0200
  Re: [PATCH v3 08/32] cris: include default ioremap_nopost()  implementation Jesper Nilsson <jesper.nilsson@axis.com> - 2017-04-11 15:20 +0200

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