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rm48x50: VFP lazy stacking 

You need to turn on RT_VFP_LAZY_STACKING in rtconfig.h. By default, RTT
will turn on VFP for all threads and stack all the VFP registers. When
doing lazy stacking, VFP will only be turned on for the thread who
issued VFP instructions.

Currently, if a thread turned on VFP, it cannot be turned off. RTT will
never know what time the thread doesn't need VFP any more. The thread
might could turn off the VFP for it self in proper time.
This commit is contained in:
Grissiom 2013-05-31 20:25:44 +08:00
parent 8bbfd45ce3
commit 24fc6e6ebb
5 changed files with 27 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
bsp/rm48x50/HALCoGen/source/sys_core.asm
View File

@ -72,8 +72,8 @@ _coreInitRegisters_
orr r2, r2, #0xF00000
mcr p15, #0x00, r2, c1, c0, #0x02
; Enable FPV
fmrx R2, fpexc
.if (RT_VFP_LAZY_STACKING) = 0
fmrx r2, fpexc
orr r2, r2, #0x40000000
fmxr fpexc, r2
@ -93,6 +93,7 @@ _coreInitRegisters_
fmdrr d13, r1, r1
fmdrr d14, r1, r1
fmdrr d15, r1, r1
.endif
bl next1
next1
bl next2

13
bsp/rm48x50/HALCoGen/source/sys_intvecs.asm
View File

@ -21,8 +21,7 @@
resetEntry
b _c_int00
undefEntry
b undefEntry
b turnon_VFP
svcEntry
b svcEntry
prefetchEntry
@ -33,5 +32,13 @@ reservedEntry
b IRQ_Handler
ldr pc,[pc,#-0x1b0]
.sect ".text"
turnon_VFP
; Enable FPV
STMDB sp!, {r0}
fmrx r0, fpexc
orr r0, r0, #0x40000000
fmxr fpexc, r0
LDMIA sp!, {r0}
subs pc, lr, #4
;-------------------------------------------------------------------------------

1
bsp/rm48x50/rtconfig.h
View File

@ -211,6 +211,7 @@
// #define RTGUI_USING_MOUSE_CURSOR
// </section>
#define RT_VFP_LAZY_STACKING
// </RDTConfigurator>
#endif

12
libcpu/arm/rm48x50/context_ccs.asm
View File

@ -75,13 +75,13 @@ __no_vfp_frame1
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0 ; restore fpexc
TST r0, #0x40000000
BEQ __no_vfp_frame2
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame2
VMSR fpexc, r0
.endif
LDMIA sp!, {r4} ; pop new task cpsr to spsr
@ -99,13 +99,13 @@ rt_hw_context_switch_to
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_to
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_to
VMSR fpexc, r0
.endif
LDMIA sp!, {r4} ; pop new task cpsr to spsr
@ -162,13 +162,13 @@ __no_vfp_frame_str_irq
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_ldr_irq
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_ldr_irq
VMSR fpexc, r0
.endif
LDMIA sp!, {r0-r12,lr}
@ -184,13 +184,13 @@ rt_hw_context_switch_interrupt_do
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_do1
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_do1
VMSR fpexc, r0
.endif
LDMIA sp!, {r0-r12,lr} ; reload saved registers
@ -216,7 +216,7 @@ __no_vfp_frame_do1
VMRS r0, fpexc
TST r0, #0x40000000
BEQ __no_vfp_frame_do2
VSTMDB sp!, {d0-d15}
VSTMDB sp!, {d0-d15}
VMRS r1, fpscr
; TODO: add support for Common VFPv3.
; Save registers like FPINST, FPINST2
@ -235,13 +235,13 @@ __no_vfp_frame_do2
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_do3
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_do3
VMSR fpexc, r0
.endif
LDMIA sp!, {r4} ; pop new task's cpsr to spsr

9
libcpu/arm/rm48x50/stack.c
View File

@ -58,8 +58,9 @@ rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter,
*(--stk) = SVCMODE; /* arm mode */
#ifdef __TI_VFP_SUPPORT__
#define VFP_DATA_NR 32
#ifndef RT_VFP_LAZY_STACKING
{
#define VFP_DATA_NR 32
int i;
for (i = 0; i < VFP_DATA_NR; i++)
@ -68,9 +69,13 @@ rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter,
}
/* FPSCR TODO: do we need to set the values other than 0? */
*(--stk) = 0;
/* FPEXC. Enable the FVP by default. */
/* FPEXC. Enable the FVP if no lazy stacking. */
*(--stk) = 0x40000000;
}
#else
/* FPEXC. Disable the FVP by default. */
*(--stk) = 0x00000000;
#endif
#endif
/* return task's current stack address */