[BSP] Update VFP code in armv6.

committed by FH.

libcpu/arm/armv6/vfp.c

+/*
+ * File      : vfp.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006, RT-Thread Develop Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2014-11-07     weety      first version
+ */
+
+#include <rthw.h>
+#include <rtthread.h>
+#include "vfp.h"
+
+#ifdef RT_USING_VFP
+
+void vfp_init(void)
+{
+    int ret = 0;
+    unsigned int value;
+    asm  volatile ("mrc p15, 0, %0, c1, c0, 2"
+            :"=r"(value)
+            :);
+    value |= 0xf00000;/*enable CP10, CP11 user access*/
+    asm volatile("mcr p15, 0, %0, c1, c0, 2"
+            :
+            :"r"(value));
+
+    asm volatile("fmrx %0, fpexc"
+            :"=r"(value));
+    value |=(1<<30);
+    asm volatile("fmxr fpexc, %0"
+            :
+            :"r"(value));
+
+}
+
+#endif

libcpu/arm/armv6/vfp_entry_gcc.S

-/*
- * File      : vfp_entry_gcc.S
- * This file is part of RT-Thread RTOS
- * COPYRIGHT (C) 2006, RT-Thread Development Team
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License along
- *  with this program; if not, write to the Free Software Foundation, Inc.,
- *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Change Logs:
- * Date           Author       Notes
- * 2014-11-07     weety    first version
- */
-
-#include <rtconfig.h>
-
-#ifdef RT_USING_VFP
-
-#include "armv6.h"
-#include "vfp.h"
-
-//#define DEBUG
-
-.macro	PRINT, str
-#ifdef DEBUG
-    stmfd sp!, {r0-r3, ip, lr}
-    add   r0, pc, #4
-    bl    rt_kprintf
-    b     1f
-    .asciz  "VFP: \str\n"
-    .balign 4
-1: ldmfd    sp!, {r0-r3, ip, lr}
-#endif
-    .endm
-
-.macro  PRINT1, str, arg
-#ifdef DEBUG
-    stmfd sp!, {r0-r3, ip, lr}
-    mov   r1, \arg
-    add   r0, pc, #4
-    bl    rt_kprintf
-    b     1f
-    .asciz  "VFP: \str\n"
-    .balign 4
-1:  ldmfd    sp!, {r0-r3, ip, lr}
-#endif
-    .endm
-
-.macro  PRINT3, str, arg1, arg2, arg3
-#ifdef DEBUG
-    stmfd sp!, {r0-r3, ip, lr}
-    mov   r3, \arg3
-    mov   r2, \arg2
-    mov   r1, \arg1
-    add   r0, pc, #4
-    bl    rt_kprintf
-    b     1f
-    .asciz  "VFP: \str\n"
-    .balign 4
-1:  ldmfd  sp!, {r0-r3, ip, lr}
-#endif
-    .endm
-
-.macro get_vfpregs_offset, rd
-    ldr \rd, .vfp_offset
-    ldr \rd, [\rd]
-    .endm
-
-.vfp_offset:
-    .word  vfpregs_offset
-
-.macro vfp_restore_working_reg, base, rd0
-    vldmia \base!, {d0-d15}
-#ifdef RT_USING_VFPv3
-    vmrs \rd0, mvfr0
-    and  \rd0, \rd0, #MVFR0_A_SIMD_MASK @ A_SIMD registers
-    cmp  \rd0, #2                       @ 0b0000  Not supported.
-                                        @ 0b0001  Supported, 16 64-bit registers.
-                                        @ 0b0010  Supported, 32 64-bit registers.
-    vldmiaeq \base!, {d16-d31}
-    addne    \base, \base, #32*4        @ skip unused registers
-#endif
-    .endm
-
-.macro vfp_save_working_reg, base, rd0
-    vstmia \base!, {d0-d15}             @ save the working registers
-#ifdef RT_USING_VFPv3
-    vmrs \rd0, mvfr0
-    and  \rd0, \rd0, #MVFR0_A_SIMD_MASK @ A_SIMD registers
-    cmp  \rd0, #2                       @ 0b0000  Not supported.
-                                        @ 0b0001  Supported, 16 64-bit registers.
-                                        @ 0b0010  Supported, 32 64-bit registers.
-    vstmiaeq \base!, {d16-d31}
-    addne    \base, \base, #32*4        @ skip unused registers
-#endif
-    .endm
-
-.macro vfp_restore_state, base, fpexc_rd, rd0, rd1, rd2
-    ldmia    \base, {\fpexc_rd, \rd0, \rd1, \rd2} @ load FPEXC, FPSCR, FPINST, FPINST2
-    tst      \fpexc_rd, #FPEXC_EX                 @ vfp is in the exceptional state?
-    beq      1f
-    vmsr     fpinst, \rd1                         @ restore fpinst
-    tst      \fpexc_rd, #FPEXC_FP2V               @ FPINST2 instruction valid
-    beq      1f
-    vmsr     fpinst2, \rd2                        @ restore fpinst2
-1:
-    vmsr     fpscr, \rd0                          @ restore fpscr
-    .endm
-
-.macro vfp_save_state, base, fpexc_rd, rd0, rd1, rd2
-    vmrs  \rd0, fpscr                          @ current status
-    tst   \fpexc_rd, #FPEXC_EX                 @ vfp is in the exceptional state?
-    beq   1f
-    vmrs  \rd1, fpinst                         @ get fpinst
-    tst   \fpexc_rd, #FPEXC_FP2V               @ FPINST2 instruction valid
-    beq   1f
-    vmrs  \rd2, fpinst2                        @ get fpinst2
-1:
-    stmia \base, {\fpexc_rd, \rd0, \rd1, \rd2} @ save FPEXC, FPSCR, FPINST, FPINST2
-    .endm
-
-
-/*
- *  VFP hardware support entry point.
- *  r0  = faulted instruction
- *  r2  = faulted PC+4
- *  r9  = successful return
- *  r10 = rt_thread structure
- *  lr  = failure return
- */
-
-.globl vfp_entry
-vfp_entry:
-    ldr  r1, =rt_interrupt_nest
-    ldr  r1, [r1]                     @ get rt_interrupt_nest
-    cmp  r1, #0                       @ rt_interrupt_nest == 0?
-    bne  irq_vfp_entry                @ irq handler used VFP
-
-    get_vfpregs_offset r11
-    add  r10, r10, r11  @ r10 = vfpregs
-
-    vmrs r1, fpexc
-    tst  r1, #FPEXC_EN
-    bne  __lookup_vfp_exceptions      @ if the VFP already enabled, now checking vfp exceptions
-
-    ldr  r3, last_vfp_context_address
-    orr  r1, r1, #FPEXC_EN            @ set VFP enable bit
-    ldr  r4, [r3]                     @ get last_vfp_context pointer
-    bic  r5, r1, #FPEXC_EX            @ clear exceptions status
-    cmp  r4, r10
-    beq  __switch_to_the_same_thread  @ switch to the same thread, checking pending exception.
-
-    vmsr fpexc, r5                    @ enable VFP, clear any pending exceptions
-
-    /* Save the current VFP registers to the old thread context */
-    cmp  r4, #0
-    beq  __no_last_vfp_context
-    vfp_save_working_reg r4, r5       @ save the working registers
-    vfp_save_state r4, r1, r5, r6, r8 @ save vfp state registers
-
-__no_last_vfp_context:
-    str    r10, [r3]                    @ update the last_vfp_context pointer
-
-    vfp_restore_working_reg r10, r5     @ restore the working registers
-    vfp_restore_state r10, r1, r5, r6, r8 @ restore vfp state registers
-
-__switch_to_the_same_thread:
-    tst      r1, #FPEXC_EX
-    bne      __do_exception
-    vmsr     fpexc, r1                  @ restore fpexc last
-    sub      r2, r2, #4
-    str      r2, [sp, #S_PC]            @ retry the faulted instruction
-    PRINT1 "return instr=0x%08x", r2
-    mov      pc, r9
-
-
-__lookup_vfp_exceptions:
-    tst   r1, #FPEXC_EX | FPEXC_DEX     @ Check for synchronous or asynchronous exception
-    bne   __do_exception
-    vmrs  r5, fpscr
-    tst   r5, #FPSCR_IXE
-    bne   __do_exception
-
-    PRINT "__lookup_vfp_exceptions"
-    mov   pc, lr
-
-__do_exception:
-    PRINT "__do_exception"
-    push  {lr}
-    mov   r5, r1
-    bic   r5, #FPEXC_EX                 @ clear exception
-    vmsr  fpexc, r5
-    bl    vfp_exception                 @ r0 = faulted instruction, r1 = fpexc
-    pop   {pc}
-    @mov   pc, lr
-
-
-irq_vfp_entry:
-    vmrs r1, fpexc
-    tst  r1, #FPEXC_EN
-    bne  __lookup_vfp_exceptions        @ if the VFP already enabled, now checking vfp exceptions
-
-    ldr  r3, last_vfp_context_address
-    orr  r1, r1, #FPEXC_EN              @ set VFP enable bit
-    ldr  r4, [r3]                       @ get last_vfp_context pointer
-    bic  r5, r1, #FPEXC_EX              @ clear exceptions status
-
-    vmsr fpexc, r5                      @ enable VFP, clear any pending exceptions
-
-    /* Save the current VFP registers to the old thread context */
-    cmp  r4, #0                         @ last_vfp_context != NULL ?
-    beq  __no_save_vfp_context
-    vfp_save_working_reg r4, r5         @ save the working registers
-    vfp_save_state r4, r1, r5, r6, r8   @ save vfp state registers
-
-    mov   r4, #0
-    str   r4, [r3]                      @ update the last_vfp_context pointer
-                                        @ last_vfp_context = NULL
-__no_save_vfp_context:
-    sub   r2, r2, #4
-    str   r2, [sp, #S_PC]               @ retry the faulted instruction
-    PRINT1 "return instr=0x%08x", r2
-    mov   pc, r9
-
-    .align
-last_vfp_context_address:
-    .word  last_vfp_context
-
-#endif