This is used to get the address of a variable when the kernel is not
running at the linked or relocated address.
Signed-off-by: Kevin Hao <haoke...@gmail.com>
---
v4: A new patch in v4.
arch/powerpc/include/asm/ppc_asm.h | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/arch/powerpc/include/asm/ppc_asm.h
b/arch/powerpc/include/asm/ppc_asm.h
index f595b98079ee..1279c59624ed 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -295,6 +295,11 @@ n:
* you want to access various offsets within it). On ppc32 this is
* identical to LOAD_REG_IMMEDIATE.
*
+ * LOAD_REG_ADDR_PIC(rn, name)
+ * Loads the address of label 'name' into register 'run'. Use this when
+ * the kernel doesn't run at the linked or relocated address. Please
+ * note that this macro will clobber the lr register.
+ *
* LOAD_REG_ADDRBASE(rn, name)
* ADDROFF(name)
* LOAD_REG_ADDRBASE loads part of the address of label 'name' into
@@ -305,6 +310,14 @@ n:
* LOAD_REG_ADDRBASE(rX, name)
* ld rY,ADDROFF(name)(rX)
*/
+
+/* Be careful, this will clobber the lr register. */
+#define LOAD_REG_ADDR_PIC(reg, name) \
+ bl 0f; \
+0: mflr reg; \
+ addis reg,reg,(name - 0b)@ha; \
+ addi reg,reg,(name - 0b)@l;
+
#ifdef __powerpc64__
#define LOAD_REG_IMMEDIATE(reg,expr) \
lis reg,(expr)@highest; \
--
1.8.3.1
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