ia64: Preserve f11-f15 around calls into firmware. Patch by John Marvin.

arch/ia64/kernel/ia64_ksyms.c

@@ -127,6 +127,8 @@ EXPORT_SYMBOL(ia64_pal_call_phys_stacked);
 EXPORT_SYMBOL(ia64_pal_call_phys_static);
 EXPORT_SYMBOL(ia64_pal_call_stacked);
 EXPORT_SYMBOL(ia64_pal_call_static);
+EXPORT_SYMBOL(ia64_load_scratch_fpregs);
+EXPORT_SYMBOL(ia64_save_scratch_fpregs);
 
 extern struct efi efi;
 EXPORT_SYMBOL(efi);

arch/ia64/kernel/pal.S

@@ -245,3 +245,48 @@ GLOBAL_ENTRY(ia64_pal_call_phys_stacked)
 	br.ret.sptk.many b0
 END(ia64_pal_call_phys_stacked)
 
+/*
+ * Save scratch fp scratch regs which aren't saved in pt_regs already (fp10-fp15).
+ *
+ * NOTE: We need to do this since firmware (SAL and PAL) may use any of the scratch
+ * regs fp-low partition.
+ *
+ * Inputs:
+ *      in0	Address of stack storage for fp regs
+ */
+GLOBAL_ENTRY(ia64_save_scratch_fpregs)
+	alloc r3=ar.pfs,1,0,0,0
+	add r2=16,in0
+	;;
+	stf.spill [in0] = f10,32
+	stf.spill [r2]  = f11,32
+	;;
+	stf.spill [in0] = f12,32
+	stf.spill [r2]  = f13,32
+	;;
+	stf.spill [in0] = f14,32
+	stf.spill [r2]  = f15,32
+	br.ret.sptk.many rp
+END(ia64_save_scratch_fpregs)
+
+/*
+ * Load scratch fp scratch regs (fp10-fp15)
+ *
+ * Inputs:
+ *      in0	Address of stack storage for fp regs
+ */
+
+GLOBAL_ENTRY(ia64_load_scratch_fpregs)
+	alloc r3=ar.pfs,1,0,0,0
+	add r2=16,in0
+	;;
+	ldf.fill  f10 = [in0],32
+	ldf.fill  f11 = [r2],32
+	;;
+	ldf.fill  f12 = [in0],32
+	ldf.fill  f13 = [r2],32
+	;;
+	ldf.fill  f14 = [in0],32
+	ldf.fill  f15 = [r2],32
+	br.ret.sptk.many rp
+END(ia64_load_scratch_fpregs)

include/asm-ia64/pal.h

@@ -78,6 +78,7 @@
 #ifndef __ASSEMBLY__
 
 #include <linux/types.h>
+#include <asm/fpu.h>
 
 /*
  * Data types needed to pass information into PAL procedures and
@@ -649,12 +650,43 @@ extern struct ia64_pal_retval ia64_pal_call_static (u64, u64, u64, u64, u64);
 extern struct ia64_pal_retval ia64_pal_call_stacked (u64, u64, u64, u64);
 extern struct ia64_pal_retval ia64_pal_call_phys_static (u64, u64, u64, u64);
 extern struct ia64_pal_retval ia64_pal_call_phys_stacked (u64, u64, u64, u64);
-
-#define PAL_CALL(iprv,a0,a1,a2,a3)		iprv = ia64_pal_call_static(a0, a1, a2, a3, 0)
-#define PAL_CALL_IC_OFF(iprv,a0,a1,a2,a3)	iprv = ia64_pal_call_static(a0, a1, a2, a3, 1)
-#define PAL_CALL_STK(iprv,a0,a1,a2,a3)		iprv = ia64_pal_call_stacked(a0, a1, a2, a3)
-#define PAL_CALL_PHYS(iprv,a0,a1,a2,a3)		iprv = ia64_pal_call_phys_static(a0, a1, a2, a3)
-#define PAL_CALL_PHYS_STK(iprv,a0,a1,a2,a3)	iprv = ia64_pal_call_phys_stacked(a0, a1, a2, a3)
+extern void ia64_save_scratch_fpregs (struct ia64_fpreg *);
+extern void ia64_load_scratch_fpregs (struct ia64_fpreg *);
+
+#define PAL_CALL(iprv,a0,a1,a2,a3) do {			\
+	struct ia64_fpreg fr[6];			\
+	ia64_save_scratch_fpregs(fr);			\
+	iprv = ia64_pal_call_static(a0, a1, a2, a3, 0);	\
+	ia64_load_scratch_fpregs(fr);			\
+} while (0)
+
+#define PAL_CALL_IC_OFF(iprv,a0,a1,a2,a3) do {		\
+	struct ia64_fpreg fr[6];			\
+	ia64_save_scratch_fpregs(fr);			\
+	iprv = ia64_pal_call_static(a0, a1, a2, a3, 1);	\
+	ia64_load_scratch_fpregs(fr);			\
+} while (0)
+
+#define PAL_CALL_STK(iprv,a0,a1,a2,a3) do {		\
+	struct ia64_fpreg fr[6];			\
+	ia64_save_scratch_fpregs(fr);			\
+	iprv = ia64_pal_call_stacked(a0, a1, a2, a3);	\
+	ia64_load_scratch_fpregs(fr);			\
+} while (0)
+
+#define PAL_CALL_PHYS(iprv,a0,a1,a2,a3) do {			\
+	struct ia64_fpreg fr[6];				\
+	ia64_save_scratch_fpregs(fr);				\
+	iprv = ia64_pal_call_phys_static(a0, a1, a2, a3);	\
+	ia64_load_scratch_fpregs(fr);				\
+} while (0)
+
+#define PAL_CALL_PHYS_STK(iprv,a0,a1,a2,a3) do {		\
+	struct ia64_fpreg fr[6];				\
+	ia64_save_scratch_fpregs(fr);				\
+	iprv = ia64_pal_call_phys_stacked(a0, a1, a2, a3);	\
+	ia64_load_scratch_fpregs(fr);				\
+} while (0)
 
 typedef int (*ia64_pal_handler) (u64, ...);
 extern ia64_pal_handler ia64_pal;

include/asm-ia64/sal.h

@@ -38,9 +38,12 @@ extern spinlock_t sal_lock;
 
 # define SAL_CALL(result,args...) do {			\
 	unsigned long flags;				\
+	struct ia64_fpreg fr[6];                        \
+	ia64_save_scratch_fpregs(fr);                   \
 	spin_lock_irqsave(&sal_lock, flags);		\
 	__SAL_CALL(result,args);			\
 	spin_unlock_irqrestore(&sal_lock, flags);	\
+	ia64_load_scratch_fpregs(fr);                   \
 } while (0)
 
 #define SAL_SET_VECTORS			0x01000000