msm: 8974: Add function to reserve memory from device tree
Memory reservations for memory pools or using memblock remove
must happen early at bootup. Add a function at early boot to
walk the flattened device tree and extract memory reservation
information from appropriate bindings in device tree. To ensure
that the memory is only reserved when a driver is enabled,
drivers must put EXPORT_COMPAT(<compat string>) in the driver
as well as adding the binding to the device tree. More
documentation is available in
Documentation/devicetree/bindings/arm/msm/memory-reserve.txt
Change-Id: I28fa71d7a30cea9af5447acb5d2dde562fa0f6de
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
diff --git a/arch/arm/mach-msm/include/mach/memory.h b/arch/arm/mach-msm/include/mach/memory.h
index 2596364..bf92f7d 100644
--- a/arch/arm/mach-msm/include/mach/memory.h
+++ b/arch/arm/mach-msm/include/mach/memory.h
@@ -118,6 +118,23 @@
(virt) - MEMBANK0_PAGE_OFFSET + MEMBANK0_PHYS_OFFSET)
#endif
+/*
+ * Need a temporary unique variable that no one will ever see to
+ * hold the compat string. Line number gives this easily.
+ * Need another layer of indirection to get __LINE__ to expand
+ * properly as opposed to appending and ending up with
+ * __compat___LINE__
+ */
+#define __CONCAT(a, b) ___CONCAT(a, b)
+#define ___CONCAT(a, b) a ## b
+
+#define EXPORT_COMPAT(com) \
+static char *__CONCAT(__compat_, __LINE__) __used \
+ __attribute((__section__(".exportcompat.init"))) = com
+
+extern char *__compat_exports_start[];
+extern char *__compat_exports_end[];
+
#endif
#if defined CONFIG_ARCH_MSM_SCORPION || defined CONFIG_ARCH_MSM_KRAIT
@@ -135,4 +152,5 @@
#ifndef CONFIG_ARCH_MSM7X27
#define CONSISTENT_DMA_SIZE (SZ_1M * 14)
+
#endif