[PATCH v6 net-next 01/10] misc: sram: add optional ioremap without write combining
From: Gregory CLEMENT <hidden>
Date: 2016-03-14 08:39:31
Also in:
lkml, netdev
Subsystem:
char and misc drivers, open firmware and flattened device tree bindings, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
From: Marcin Wojtas <redacted> Some SRAM users may require non-bufferable access to the memory, which is impossible, because devm_ioremap_wc() is used for setting sram->virt_base. This commit adds optional flag 'no-memory-wc', which allow to choose remap method, using DT property. Documentation is updated accordingly. Signed-off-by: Marcin Wojtas <redacted> --- Documentation/devicetree/bindings/sram/sram.txt | 5 +++++ drivers/misc/sram.c | 5 ++++- 2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/sram/sram.txt b/Documentation/devicetree/bindings/sram/sram.txt
index 42ee9438b771..227e3a341af1 100644
--- a/Documentation/devicetree/bindings/sram/sram.txt
+++ b/Documentation/devicetree/bindings/sram/sram.txt@@ -25,6 +25,11 @@ Required properties in the sram node: - ranges : standard definition, should translate from local addresses within the sram to bus addresses +Optional properties in the sram node: + +- no-memory-wc : the flag indicating, that SRAM memory region has not to + be remapped as write combining. WC is used by default. + Required properties in the area nodes: - reg : iomem address range, relative to the SRAM range
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
index 736dae715dbf..69cdabea9c03 100644
--- a/drivers/misc/sram.c
+++ b/drivers/misc/sram.c@@ -360,7 +360,10 @@ static int sram_probe(struct platform_device *pdev) return -EBUSY; } - sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size); + if (of_property_read_bool(pdev->dev.of_node, "no-memory-wc")) + sram->virt_base = devm_ioremap(sram->dev, res->start, size); + else + sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size); if (IS_ERR(sram->virt_base)) return PTR_ERR(sram->virt_base);
--
2.5.0