[RFC,03/11] misc: SRAM: Add option to map SRAM to allow code execution

Commit Message

Russ Dill Sept. 17, 2013, 12:43 p.m. UTC

This is necessary for platforms that use SRAM to execute suspend/resume stubs.

Signed-off-by: Russ Dill <[e-mail]>
---
 Documentation/devicetree/bindings/misc/sram.txt |  4 ++++
 drivers/misc/sram.c                             | 13 ++++++++++++-
 include/linux/platform_data/sram.h              |  8 ++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 include/linux/platform_data/sram.h

Patch

diff --git a/Documentation/devicetree/bindings/misc/sram.txt b/Documentation/devicetree/bindings/misc/sram.txt
index 4d0a00e..4fa9af3 100644
--- a/Documentation/devicetree/bindings/misc/sram.txt
+++ b/Documentation/devicetree/bindings/misc/sram.txt
@@ -8,6 +8,10 @@  Required properties:
 
 - reg : SRAM iomem address range
 
+Optional properties:
+
+- map-exec: Map range to allow code execution
+
 Example:
 
 sram: sram@5c000000 {
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
index d87cc91..baa5008 100644
--- a/drivers/misc/sram.c
+++ b/drivers/misc/sram.c
@@ -28,6 +28,7 @@ 
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/genalloc.h>
+#include <linux/platform_data/sram.h>
 
 #define SRAM_GRANULARITY	32
 
@@ -38,14 +39,24 @@  struct sram_dev {
 
 static int sram_probe(struct platform_device *pdev)
 {
+	struct sram_platform_data *pdata = pdev->dev.platform_data;
 	void __iomem *virt_base;
 	struct sram_dev *sram;
 	struct resource *res;
 	unsigned long size;
+	bool map_exec = false;
 	int ret;
 
+	if (of_get_property(pdev->dev.of_node, "map-exec", NULL))
+		map_exec = true;
+	if (pdata && pdata->map_exec)
+		map_exec |= true;
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	virt_base = devm_ioremap_resource(&pdev->dev, res);
+	if (map_exec)
+		virt_base = devm_ioremap_exec_resource(&pdev->dev, res);
+	else
+		virt_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(virt_base))
 		return PTR_ERR(virt_base);
 
diff --git a/include/linux/platform_data/sram.h b/include/linux/platform_data/sram.h
new file mode 100644
index 0000000..8f5c4ba
--- /dev/null
+++ b/include/linux/platform_data/sram.h
@@ -0,0 +1,8 @@ 
+#ifndef _LINUX_SRAM_H
+#define _LINUX_SRAM_H
+
+struct sram_platform_data {
+	bool map_exec;
+};
+
+#endif