powerpc: Add denormalisation exception handling for POWER6/7
On POWER6 and POWER7 if the input operand to an instruction is a denormalised single precision binary floating point value we can take a denormalisation exception where it's expected that the hypervisor (HV=1) will fix up the inputs before the instruction is run. This adds code to handle this denormalisation exception for POWER6 and POWER7. It also add a CONFIG_PPC_DENORMALISATION option and sets it in pseries/ppc64_defconfig. This is useful on bare metal systems only. Based on patch from Milton Miller. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Neuling
committed by
Benjamin Herrenschmidt
Benjamin Herrenschmidt
parent
eda485f06d
commit
b92a66a65c
@@ -275,6 +275,31 @@ vsx_unavailable_pSeries_1:
|
||||
STD_EXCEPTION_PSERIES(0x1300, 0x1300, instruction_breakpoint)
|
||||
KVM_HANDLER_PR_SKIP(PACA_EXGEN, EXC_STD, 0x1300)
|
||||
|
||||
. = 0x1500
|
||||
.global denorm_Hypervisor
|
||||
denorm_exception_hv:
|
||||
HMT_MEDIUM
|
||||
mtspr SPRN_SPRG_HSCRATCH0,r13
|
||||
mfspr r13,SPRN_SPRG_HPACA
|
||||
std r9,PACA_EXGEN+EX_R9(r13)
|
||||
std r10,PACA_EXGEN+EX_R10(r13)
|
||||
std r11,PACA_EXGEN+EX_R11(r13)
|
||||
std r12,PACA_EXGEN+EX_R12(r13)
|
||||
mfspr r9,SPRN_SPRG_HSCRATCH0
|
||||
std r9,PACA_EXGEN+EX_R13(r13)
|
||||
mfcr r9
|
||||
|
||||
#ifdef CONFIG_PPC_DENORMALISATION
|
||||
mfspr r10,SPRN_HSRR1
|
||||
mfspr r11,SPRN_HSRR0 /* save HSRR0 */
|
||||
andis. r10,r10,(HSRR1_DENORM)@h /* denorm? */
|
||||
addi r11,r11,-4 /* HSRR0 is next instruction */
|
||||
bne+ denorm_assist
|
||||
#endif
|
||||
|
||||
EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
|
||||
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x1500)
|
||||
|
||||
#ifdef CONFIG_CBE_RAS
|
||||
STD_EXCEPTION_HV(0x1600, 0x1602, cbe_maintenance)
|
||||
KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0x1602)
|
||||
@@ -336,6 +361,103 @@ do_stab_bolted_pSeries:
|
||||
KVM_HANDLER_PR(PACA_EXGEN, EXC_STD, 0x900)
|
||||
KVM_HANDLER(PACA_EXGEN, EXC_HV, 0x982)
|
||||
|
||||
#ifdef CONFIG_PPC_DENORMALISATION
|
||||
denorm_assist:
|
||||
BEGIN_FTR_SECTION
|
||||
/*
|
||||
* To denormalise we need to move a copy of the register to itself.
|
||||
* For POWER6 do that here for all FP regs.
|
||||
*/
|
||||
mfmsr r10
|
||||
ori r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
|
||||
xori r10,r10,(MSR_FE0|MSR_FE1)
|
||||
mtmsrd r10
|
||||
sync
|
||||
fmr 0,0
|
||||
fmr 1,1
|
||||
fmr 2,2
|
||||
fmr 3,3
|
||||
fmr 4,4
|
||||
fmr 5,5
|
||||
fmr 6,6
|
||||
fmr 7,7
|
||||
fmr 8,8
|
||||
fmr 9,9
|
||||
fmr 10,10
|
||||
fmr 11,11
|
||||
fmr 12,12
|
||||
fmr 13,13
|
||||
fmr 14,14
|
||||
fmr 15,15
|
||||
fmr 16,16
|
||||
fmr 17,17
|
||||
fmr 18,18
|
||||
fmr 19,19
|
||||
fmr 20,20
|
||||
fmr 21,21
|
||||
fmr 22,22
|
||||
fmr 23,23
|
||||
fmr 24,24
|
||||
fmr 25,25
|
||||
fmr 26,26
|
||||
fmr 27,27
|
||||
fmr 28,28
|
||||
fmr 29,29
|
||||
fmr 30,30
|
||||
fmr 31,31
|
||||
FTR_SECTION_ELSE
|
||||
/*
|
||||
* To denormalise we need to move a copy of the register to itself.
|
||||
* For POWER7 do that here for the first 32 VSX registers only.
|
||||
*/
|
||||
mfmsr r10
|
||||
oris r10,r10,MSR_VSX@h
|
||||
mtmsrd r10
|
||||
sync
|
||||
XVCPSGNDP(0,0,0)
|
||||
XVCPSGNDP(1,1,1)
|
||||
XVCPSGNDP(2,2,2)
|
||||
XVCPSGNDP(3,3,3)
|
||||
XVCPSGNDP(4,4,4)
|
||||
XVCPSGNDP(5,5,5)
|
||||
XVCPSGNDP(6,6,6)
|
||||
XVCPSGNDP(7,7,7)
|
||||
XVCPSGNDP(8,8,8)
|
||||
XVCPSGNDP(9,9,9)
|
||||
XVCPSGNDP(10,10,10)
|
||||
XVCPSGNDP(11,11,11)
|
||||
XVCPSGNDP(12,12,12)
|
||||
XVCPSGNDP(13,13,13)
|
||||
XVCPSGNDP(14,14,14)
|
||||
XVCPSGNDP(15,15,15)
|
||||
XVCPSGNDP(16,16,16)
|
||||
XVCPSGNDP(17,17,17)
|
||||
XVCPSGNDP(18,18,18)
|
||||
XVCPSGNDP(19,19,19)
|
||||
XVCPSGNDP(20,20,20)
|
||||
XVCPSGNDP(21,21,21)
|
||||
XVCPSGNDP(22,22,22)
|
||||
XVCPSGNDP(23,23,23)
|
||||
XVCPSGNDP(24,24,24)
|
||||
XVCPSGNDP(25,25,25)
|
||||
XVCPSGNDP(26,26,26)
|
||||
XVCPSGNDP(27,27,27)
|
||||
XVCPSGNDP(28,28,28)
|
||||
XVCPSGNDP(29,29,29)
|
||||
XVCPSGNDP(30,30,30)
|
||||
XVCPSGNDP(31,31,31)
|
||||
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
|
||||
mtspr SPRN_HSRR0,r11
|
||||
mtcrf 0x80,r9
|
||||
ld r9,PACA_EXGEN+EX_R9(r13)
|
||||
ld r10,PACA_EXGEN+EX_R10(r13)
|
||||
ld r11,PACA_EXGEN+EX_R11(r13)
|
||||
ld r12,PACA_EXGEN+EX_R12(r13)
|
||||
ld r13,PACA_EXGEN+EX_R13(r13)
|
||||
HRFID
|
||||
b .
|
||||
#endif
|
||||
|
||||
.align 7
|
||||
/* moved from 0xe00 */
|
||||
STD_EXCEPTION_HV(., 0xe02, h_data_storage)
|
||||
@@ -495,6 +617,7 @@ machine_check_common:
|
||||
STD_EXCEPTION_COMMON(0xe60, hmi_exception, .unknown_exception)
|
||||
STD_EXCEPTION_COMMON_ASYNC(0xf00, performance_monitor, .performance_monitor_exception)
|
||||
STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception)
|
||||
STD_EXCEPTION_COMMON(0x1502, denorm, .unknown_exception)
|
||||
#ifdef CONFIG_ALTIVEC
|
||||
STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception)
|
||||
#else
|
||||
|
||||
Reference in New Issue
Block a user