@ r2 = faulted PC+4
@ r9 = successful return
@ r10 = vfp_state union
+@ r11 = CPU number
@ lr = failure return
.globl vfp_support_entry
VFPFMRX r1, FPEXC @ Is the VFP enabled?
DBGSTR1 "fpexc %08x", r1
- tst r1, #FPEXC_ENABLE
+ tst r1, #FPEXC_EN
bne look_for_VFP_exceptions @ VFP is already enabled
DBGSTR1 "enable %x", r10
ldr r3, last_VFP_context_address
- orr r1, r1, #FPEXC_ENABLE @ user FPEXC has the enable bit set
- ldr r4, [r3] @ last_VFP_context pointer
- bic r5, r1, #FPEXC_EXCEPTION @ make sure exceptions are disabled
+ orr r1, r1, #FPEXC_EN @ user FPEXC has the enable bit set
+ ldr r4, [r3, r11, lsl #2] @ last_VFP_context pointer
+ bic r5, r1, #FPEXC_EX @ make sure exceptions are disabled
cmp r4, r10
beq check_for_exception @ we are returning to the same
@ process, so the registers are
@ exceptions, so we can get at the
@ rest of it
+#ifndef CONFIG_SMP
@ Save out the current registers to the old thread state
+ @ No need for SMP since this is not done lazily
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
+#endif
no_old_VFP_process:
DBGSTR1 "load state %p", r10
- str r10, [r3] @ update the last_VFP_context pointer
+ 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:
- tst r1, #FPEXC_EXCEPTION
+ tst r1, #FPEXC_EX
bne process_exception @ might as well handle the pending
@ exception before retrying branch
@ out before setting an FPEXC that
look_for_VFP_exceptions:
- tst r1, #FPEXC_EXCEPTION
+ @ 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_EXCEPTION !
+ tst r5, #FPSCR_IXE
bne process_exception
@ Fall into hand on to next handler - appropriate coproc instr
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.
@ 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
+#ifdef CONFIG_SMP
+ .globl vfp_save_state
+ .type vfp_save_state, %function
+vfp_save_state:
+ @ Save the current VFP state
+ @ r0 - save location
+ @ r1 - FPEXC
+ DBGSTR1 "save VFP state %p", r0
+ VFPFSTMIA r0, r2 @ save the working registers
+ VFPFMRX r2, FPSCR @ current status
+ 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
+
last_VFP_context_address:
.word last_VFP_context
.globl vfp_put_float
vfp_put_float:
- add pc, pc, r0, lsl #3
+ add pc, pc, r1, lsl #3
mov r0, r0
.irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
- mcr p10, 0, r1, c\dr, c0, 0 @ fmsr r0, s0
+ mcr p10, 0, r0, c\dr, c0, 0 @ fmsr r0, s0
mov pc, lr
- mcr p10, 0, r1, c\dr, c0, 4 @ fmsr r0, s1
+ mcr p10, 0, r0, c\dr, c0, 4 @ fmsr r0, s1
mov pc, lr
.endr
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
.globl vfp_put_double
vfp_put_double:
- add pc, pc, r0, lsl #3
+ add pc, pc, r2, lsl #3
mov r0, r0
.irp dr,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
- fmdrr d\dr, r1, r2
+ 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
projects / linux-2.6 / blobdiff