[libcpu] remove nds32 porting

libcpu/nds32/context_gcc.S

@@ -1,188 +0,0 @@
-#include "nds32.h"
-#include "os_cpu_common.h"
-#include "config.h"
-
-	.align 4
-! void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
-! R0 --> from
-! R1 --> to
-    .section .text
-    .global rt_hw_context_switch_interrupt
-    .global rt_hw_context_switch
-rt_hw_context_switch_interrupt:
-rt_hw_context_switch:
-	push25 $r6,#8    ! {$r6, $fp, $gp, $lp}
-
-    la     $r2, rt_thread_switch_interrupt_flag
-    lw     $r3, [$r2]
-    movi   $r4, #1
-    beq    $r3, $r4, _reswitch
-    sw     $r4, [$r2]                           ! set rt_thread_switch_interrupt_flag to 1
-
-    la     $r2, rt_interrupt_from_thread
-    sw     $r0, [$r2]                           ! set rt_interrupt_from_thread
-_reswitch:
-	la     $r2, rt_interrupt_to_thread
-    sw     $r1, [$r2]                           ! set rt_interrupt_to_thread
-    bal    hal_intc_swi_trigger                 ! trigger the swi exception (causes context switch)
-
-	pop25  $r6,#8    ! {$r6, $fp, $gp, $lp}
-
-! R0 --> switch from thread stack
-! R1 --> switch to thread stack
-! psr, pc, LR, R12, R3, R2, R1, R0 are pushed into [from] stack
-
-	.align 4
-	.global OS_Trap_Interrupt_SWI
-OS_Trap_Interrupt_SWI:
-!	pushm $r0, $r5
-    setgie.d                                     ! disable interrupt to protect context switch
-	dsb
-
-    IntlDescend                                  ! Descend interrupt level
-
-	movi	$r0, 0x0
-	mtsr	$r0, $INT_PEND                       ! clean SWI pending
-
-	la      $r0, rt_thread_switch_interrupt_flag ! get rt_thread_switch_interrupt_flag
-	lw      $r1, [$r0]
-	beqz    $r1, pendsv_exit                     ! swi has already been handled
-
-	movi    $r1, #0
-	sw      $r1, [$r0]                           ! clear rt_thread_switch_interrupt_flag to 0
-
-	la      $r0, rt_interrupt_from_thread
-	lw      $r1, [$r0]
-	beqz    $r1, switch_to_thread                ! skip register save at the first time(os startup phase)
-
-	SAVE_ALL
-
-	move    $r1, $sp
-	la      $r0, rt_interrupt_from_thread
-	lw      $r0, [$r0]
-	sw      $r1, [$r0]
-
-switch_to_thread:
-    la     $r1, rt_interrupt_to_thread
-    lw     $r1, [$r1]
-    lw     $r1, [$r1]                            ! load thread stack pointer
-	move   $sp, $r1                              ! update stack pointer
-	RESTORE_ALL                                  ! pop registers
-
-pendsv_exit:
-	setgie.e
-	iret
-
-	.align 4
-! void rt_hw_context_switch_to(rt_uint32 to);
-! R0 --> to
-    .global rt_hw_context_switch_to
-rt_hw_context_switch_to:
-    la     $r1, rt_interrupt_to_thread
-    sw     $r0, [$r1]
-
-    ! set from thread to 0
-    la     $r1, rt_interrupt_from_thread
-    movi   $r0, #0
-    sw     $r0, [$r1]
-
-    ! set interrupt flag to 1
-    la     $r1, rt_thread_switch_interrupt_flag
-    movi   $r0, #1
-    sw     $r0, [$r1]
-
-    ! set the SWI exception priority(must be the lowest level)
-	! todo
-
-    ! trigger the SWI exception (causes context switch)
-    jal    hal_intc_swi_trigger
-
-    setgie.e            ! enable interrupts at processor level
-
-1:
-	b   1b              ! never reach here
-
-#ifndef VECTOR_NUMINTRS
-#define VECTOR_NUMINTRS		32
-#endif
-
-	.global OS_Trap_Int_Common
-
-	! Set up Interrupt vector ISR
-	! HW#IRQ_SWI_VECTOR : OS_Trap_Interrupt_SWI (SWI)
-	! HW#n : OS_Trap_Int_Common
-
-	.macro	SET_HWISR num
-	.global OS_Trap_Interrupt_HW\num
-	.if	\num == IRQ_SWI_VECTOR
-	.set	OS_Trap_Interrupt_HW\num, OS_Trap_Interrupt_SWI
-	.else
-	.set	OS_Trap_Interrupt_HW\num, OS_Trap_Int_Common
-	.endif
-	.endm
-
-	.altmacro
-	.set	irqno, 0
-	.rept	VECTOR_NUMINTRS
-	SET_HWISR %irqno
-	.set	irqno, irqno+1
-	.endr
-	.noaltmacro
-
-!	.global OS_Trap_Int_Common
-OS_Trap_Int_Common:
-#ifdef MPU_SUPPORT
-	mfsr	$p1, $PSW
-	ori	$p1, $p1, (PSW_mskIT | PSW_mskDT)
-	mtsr	$p1, $PSW                       ! enable IT/DT
-	dsb
-	pushm	$r0, $r5
-	move	$r0, $p0                        ! IRQ number
-#endif
-	! $r0 : HW Interrupt vector number
-	SAVE_CALLER
-
-	IntlDescend                             ! Descend interrupt level
-
-	mfsr	$r1, $IPSW                      ! Use IPSW.CPL to check come from thread or ISR
-	srli45	$r1, #PSW_offCPL
-	fexti33	$r1, #0x2                       ! IPSW.CPL
-	bnec	$r1, #0x7, 2f                   ! IPSW.CPL != 7, come form ISR, reentrant
-
-	move	$fp, $sp                        ! save old stack pointer
-	la	    $sp, __OS_Int_Stack             ! switch to interrupt stack
-2:
-	setgie.e                                ! allow nested now
-
-	! The entire CPU state is now stashed on the stack,
-	! and the stack is also 8-byte alignment.
-	! We can call C program based interrupt handler now.
-	la	    $r1, OS_CPU_Vector_Table
-	lw	    $r1, [$r1+($r0<<2)]             ! ISR function pointer
-	jral	$r1                             ! Call ISR
-
-	la	    $r1, __OS_Int_Stack             ! Check for nested interruption return
-	bne	    $r1, $sp, 3f                    ! $sp != __OS_Int_Stack?
-
-	move	$sp, $fp                        ! Move back to the thread stack
-3:
-	RESTORE_CALLER
-
-	iret
-
-!	.set	OS_Trap_Interrupt_HW9, OS_Trap_Interrupt_SWI
-!	.set	OS_Trap_Interrupt_HW19, OS_Trap_Int_Common
-
-!*********************************************
-! POINTERS TO VARIABLES
-!*********************************************
-#ifdef MPU_SUPPORT
-	.section privileged_data
-#else
-	.section .bss
-#endif
-	.skip IRQ_STACK_SIZE
-	.align 3
-__OS_Int_Stack:
-
-	.end

libcpu/nds32/cpuport.c

@@ -1,202 +0,0 @@
-/*
- * File      : cpuport.c
- *  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
- * 2017-08-25   Archer      first version
- */
-
-#include <rtthread.h>
-
-#include "nds32.h"
-
-/*
- * Initialise the stack of a task to look exactly as if a call to
- * SAVE_CONTEXT had been called.
- *
- * See header file for description.
- *
- *
- * Stack Layout:
- *                High  |-----------------|
- *                      |       $R5       |
- *                      |-----------------|
- *                      |        .        |
- *                      |        .        |
- *                      |-----------------|
- *                      |       $R0       |
- *                      |-----------------|
- *                      |       $R30 (LP) |
- *                      |-----------------|
- *                      |       $R29 (GP) |
- *                      |-----------------|
- *                      |       $R28 (FP) |
- *                      |-----------------|
- *                      |   $R15   $R27   |
- *                      |-----------------|
- *                      |   $R10   $R26   |
- *                      |-----------------|
- *                      |        .        |
- *                      |        .        |
- *                      |-----------------|
- *                      |       $R6       |
- *                      |-----------------|
- *                      |       $IFC_LP   | (Option)
- *                      |-----------------|
- *                      |   $LC/$LE/$LB   | (Option)
- *                      |       (ZOL)     |
- *                      |-----------------|
- *                      |       $IPSW     |
- *                      |-----------------|
- *                      |       $IPC      |
- *                      |-----------------|
- *                      |    Dummy word   | (Option, only exist when IFC & ZOL both configured)
- *                      |-----------------|
- *                      |       $FPU      | (Option)
- *                      |-----------------|
- *                Low
- *
- */
-
-struct stack_frame
-{
-    rt_uint32_t topOfStack[34];
-};
-
-/* flag in interrupt handling */
-rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread;
-rt_uint32_t rt_thread_switch_interrupt_flag;
-/* exception hook */
-static rt_err_t (*rt_exception_hook)(void *context) = RT_NULL;
-
-rt_base_t rt_hw_interrupt_disable(void)
-{
-    rt_base_t level = __nds32__mfsr(NDS32_SR_PSW);
-
-    GIE_DISABLE();
-
-    return level;
-}
-
-void rt_hw_interrupt_enable(rt_base_t level)
-{
-    if (level & PSW_mskGIE)
-        GIE_ENABLE();
-}
-
-/* For relax support, must initial $gp at task init*/
-extern uint32_t _SDA_BASE_ __attribute__ ((weak));
-
-/**************************************************************
- * This function will initialize thread stack
- *
- * @param tentry the entry of thread
- * @param parameter the parameter of entry
- * @param stack_addr the beginning stack address
- * @param texit the function will be called when thread exit
- *
- * @return stack address
- **************************************************************/
-rt_uint8_t *rt_hw_stack_init(void       *tentry,
-                             void       *parameter,
-                             rt_uint8_t *stack_addr,
-                             void       *texit)
-{
-    rt_int32_t i;
-    rt_uint32_t *pxTopOfStack;
-
-    pxTopOfStack = (rt_uint32_t *)RT_ALIGN_DOWN((rt_uint32_t)stack_addr, 4);
-
-    /* Simulate the stack frame as it would be created by a context switch */
-    /* R0 ~ R5 registers */
-    for (i = 5; i >= 1; i--)                         /* R5, R4, R3, R2 and R1. */
-        *--pxTopOfStack = (rt_uint32_t)0x01010101UL * i;
-    *--pxTopOfStack = (rt_uint32_t)parameter;        /* R0 : Argument */
-
-    /* R6 ~ R30 registers */
-    *--pxTopOfStack = (rt_uint32_t)texit;   /* R30: $LP */
-    *--pxTopOfStack = (rt_uint32_t)&_SDA_BASE_;         /* R29: $GP */
-    *--pxTopOfStack = (rt_uint32_t)0x2828282828;        /* R28: $FP */
-#ifdef __NDS32_REDUCE_REGS__
-    *--pxTopOfStack = (rt_uint32_t)0x1515151515;        /* R15 */
-    for (i = 10; i >= 6; i--)                           /* R10 ~ R6 */
-        *--pxTopOfStack = (rt_uint32_t)0x01010101UL * i;
-#else
-    for (i = 27; i >= 6; i--)                           /* R27 ~ R6 */
-        *--pxTopOfStack = (rt_uint32_t)0x01010101UL * i;
-#endif
-
-    /* IFC system register */
-#ifdef __TARGET_IFC_EXT
-    *--pxTopOfStack = (rt_uint32_t)0x0;                 /* $IFC_LP */
-#endif
-
-    /* ZOL system registers */
-#ifdef __TARGET_ZOL_EXT
-    *--pxTopOfStack = (rt_uint32_t)0x0;                 /* $LC */
-    *--pxTopOfStack = (rt_uint32_t)0x0;                 /* $LE */
-    *--pxTopOfStack = (rt_uint32_t)0x0;                 /* $LB */
-#endif
-
-    /* IPSW and IPC system registers */
-    /* Default IPSW: enable GIE, set CPL to 7, clear IFCON */
-    i = (__nds32__mfsr(NDS32_SR_PSW) | PSW_mskGIE | PSW_mskCPL) & ~PSW_mskIFCON;
-    *--pxTopOfStack = (rt_uint32_t)i;                /* $IPSW */
-    *--pxTopOfStack = (rt_uint32_t)tentry;           /* $IPC */
-
-    /* Dummy word for 8-byte stack alignment */
-#if defined(__TARGET_IFC_EXT) && defined(__TARGET_ZOL_EXT)
-    *--pxTopOfStack = (rt_uint32_t)0xFFFFFFFF;          /* Dummy */
-#endif
-
-    /* FPU registers */
-#ifdef __TARGET_FPU_EXT
-    for (i = 0; i < FPU_REGS; i++)
-        *--pxTopOfStack = (rt_uint32_t)0x0;         /* FPU */
-#endif
-
-    return (rt_uint8_t *)pxTopOfStack;
-}
-
-/**
- * This function set the hook, which is invoked on fault exception handling.
- *
- * @param exception_handle the exception handling hook function.
- */
-void rt_hw_exception_install(rt_err_t (*exception_handle)(void* context))
-{
-    rt_exception_hook = exception_handle;
-}
-
-#ifdef RT_USING_CPU_FFS
-/**
- * This function finds the first bit set (beginning with the least significant bit)
- * in value and return the index of that bit.
- *
- * Bits are numbered starting at 1 (the least significant bit).  A return value of
- * zero from any of these functions means that the argument was zero.
- *
- * @return return the index of the first bit set. If value is 0, then this function
- * shall return 0.
- */
-#if defined(__GNUC__)
-int __rt_ffs(int value)
-{
-    return __builtin_ffs(value);
-}
-#endif
-
-#endif