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Diffstat (limited to 'arch/arm/vfp/vfphw.S')
-rw-r--r--arch/arm/vfp/vfphw.S60
1 files changed, 37 insertions, 23 deletions
diff --git a/arch/arm/vfp/vfphw.S b/arch/arm/vfp/vfphw.S
index 0ac022f800a..353f9e5c791 100644
--- a/arch/arm/vfp/vfphw.S
+++ b/arch/arm/vfp/vfphw.S
@@ -99,12 +99,12 @@ vfp_support_entry:
DBGSTR1 "save old state %p", r4
cmp r4, #0
beq no_old_VFP_process
+ VFPFSTMIA r4, r5 @ save the working registers
VFPFMRX r5, FPSCR @ current status
- VFPFMRX r6, FPINST @ FPINST (always there, rev0 onwards)
- tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
- VFPFMRX r8, FPINST2, NE @ FPINST2 if needed - avoids reading
- @ nonexistant reg on rev0
- VFPFSTMIA r4 @ save the working registers
+ tst r1, #FPEXC_EX @ is there additional state to save?
+ VFPFMRX r6, FPINST, NE @ FPINST (only if FPEXC.EX is set)
+ tstne r1, #FPEXC_FP2V @ is there an FPINST2 to read?
+ VFPFMRX r8, FPINST2, NE @ FPINST2 if needed (and present)
stmia r4, {r1, r5, r6, r8} @ save FPEXC, FPSCR, FPINST, FPINST2
@ and point r4 at the word at the
@ start of the register dump
@@ -114,13 +114,13 @@ no_old_VFP_process:
DBGSTR1 "load state %p", r10
str r10, [r3, r11, lsl #2] @ update the last_VFP_context pointer
@ Load the saved state back into the VFP
- VFPFLDMIA r10 @ reload the working registers while
+ VFPFLDMIA r10, r5 @ reload the working registers while
@ FPEXC is in a safe state
ldmia r10, {r1, r5, r6, r8} @ load FPEXC, FPSCR, FPINST, FPINST2
- tst r1, #FPEXC_FPV2 @ is there an FPINST2 to write?
- VFPFMXR FPINST2, r8, NE @ FPINST2 if needed - avoids writing
- @ nonexistant reg on rev0
- VFPFMXR FPINST, r6
+ tst r1, #FPEXC_EX @ is there additional state to restore?
+ VFPFMXR FPINST, r6, NE @ restore FPINST (only if FPEXC.EX is set)
+ tstne r1, #FPEXC_FP2V @ is there an FPINST2 to write?
+ VFPFMXR FPINST2, r8, NE @ FPINST2 if needed (and present)
VFPFMXR FPSCR, r5 @ restore status
check_for_exception:
@@ -136,10 +136,14 @@ check_for_exception:
look_for_VFP_exceptions:
- tst r1, #FPEXC_EX
+ @ Check for synchronous or asynchronous exception
+ tst r1, #FPEXC_EX | FPEXC_DEX
bne process_exception
+ @ On some implementations of the VFP subarch 1, setting FPSCR.IXE
+ @ causes all the CDP instructions to be bounced synchronously without
+ @ setting the FPEXC.EX bit
VFPFMRX r5, FPSCR
- tst r5, #FPSCR_IXE @ IXE doesn't set FPEXC_EX !
+ tst r5, #FPSCR_IXE
bne process_exception
@ Fall into hand on to next handler - appropriate coproc instr
@@ -150,10 +154,6 @@ look_for_VFP_exceptions:
process_exception:
DBGSTR "bounce"
- sub r2, r2, #4
- str r2, [sp, #S_PC] @ retry the instruction on exit from
- @ the imprecise exception handling in
- @ the support code
mov r2, sp @ nothing stacked - regdump is at TOS
mov lr, r9 @ setup for a return to the user code.
@@ -161,7 +161,7 @@ process_exception:
@ r0 holds the trigger instruction
@ r1 holds the FPEXC value
@ r2 pointer to register dump
- b VFP9_bounce @ we have handled this - the support
+ b VFP_bounce @ we have handled this - the support
@ code will raise an exception if
@ required. If not, the user code will
@ retry the faulted instruction
@@ -174,12 +174,12 @@ vfp_save_state:
@ r0 - save location
@ r1 - FPEXC
DBGSTR1 "save VFP state %p", r0
+ VFPFSTMIA r0, r2 @ save the working registers
VFPFMRX r2, FPSCR @ current status
- VFPFMRX r3, FPINST @ FPINST (always there, rev0 onwards)
- tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
- VFPFMRX r12, FPINST2, NE @ FPINST2 if needed - avoids reading
- @ nonexistant reg on rev0
- VFPFSTMIA r0 @ save the working registers
+ tst r1, #FPEXC_EX @ is there additional state to save?
+ VFPFMRX r3, FPINST, NE @ FPINST (only if FPEXC.EX is set)
+ tstne r1, #FPEXC_FP2V @ is there an FPINST2 to read?
+ VFPFMRX r12, FPINST2, NE @ FPINST2 if needed (and present)
stmia r0, {r1, r2, r3, r12} @ save FPEXC, FPSCR, FPINST, FPINST2
mov pc, lr
#endif
@@ -217,8 +217,15 @@ vfp_get_double:
fmrrd r0, r1, d\dr
mov pc, lr
.endr
+#ifdef CONFIG_VFPv3
+ @ d16 - d31 registers
+ .irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+ mrrc p11, 3, r0, r1, c\dr @ fmrrd r0, r1, d\dr
+ mov pc, lr
+ .endr
+#endif
- @ virtual register 16 for compare with zero
+ @ virtual register 16 (or 32 if VFPv3) for compare with zero
mov r0, #0
mov r1, #0
mov pc, lr
@@ -231,3 +238,10 @@ vfp_put_double:
fmdrr d\dr, r0, r1
mov pc, lr
.endr
+#ifdef CONFIG_VFPv3
+ @ d16 - d31 registers
+ .irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+ mcrr p11, 3, r1, r2, c\dr @ fmdrr r1, r2, d\dr
+ mov pc, lr
+ .endr
+#endif