summaryrefslogtreecommitdiff
path: root/plugins/ao/eng_dsf/arm7.c
diff options
context:
space:
mode:
Diffstat (limited to 'plugins/ao/eng_dsf/arm7.c')
-rw-r--r--plugins/ao/eng_dsf/arm7.c278
1 files changed, 0 insertions, 278 deletions
diff --git a/plugins/ao/eng_dsf/arm7.c b/plugins/ao/eng_dsf/arm7.c
deleted file mode 100644
index b4314948..00000000
--- a/plugins/ao/eng_dsf/arm7.c
+++ /dev/null
@@ -1,278 +0,0 @@
-//
-// ARM7 processor emulator
-// version 1.6 / 2008-02-16
-// (c) Radoslaw Balcewicz
-//
-
-#include "arm7.h"
-#include "arm7i.h"
-
-#ifdef ARM7_THUMB
-#include "arm7thumb.h"
-#endif
-
- //--------------------------------------------------------------------------
- // definitions and macros
-
- /** Macro for accessing banked registers. */
-#define RX_BANK(t,r) (cpu->Rx_bank [t][r - 8])
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- // private functions
-
- /** CPU Reset. */
-static void Reset (struct sARM7 *cpu);
- //--------------------------------------------------------------------------
-
- // private variables
-
- /** Table for decoding bit-coded mode to zero based index. */
-static const int s_tabTryb [32] = {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
- -1, -1, -1, -1, -1, -1, ARM7_MODE_usr, ARM7_MODE_fiq, ARM7_MODE_irq,
- ARM7_MODE_svc, -1, -1, -1, ARM7_MODE_abt, -1, -1, -1, ARM7_MODE_und,
- -1, -1, -1, ARM7_MODE_sys};
- //--------------------------------------------------------------------------
-
-
- // public functions
-
-struct sARM7* ARM7_Alloc ()
-{
- struct sARM7 *cpu = malloc (sizeof (struct sARM7));
- memset (cpu, 0, sizeof (struct sARM7));
- return cpu;
-}
-
-void ARM7_Free (struct sARM7 *cpu) {
- free (cpu);
-}
-
- //--------------------------------------------------------------------------
- /** ARM7 emulator init. */
-void ARM7_Init (struct sARM7 *cpu)
- {
- // sane startup values
- cpu->fiq = 0;
- cpu->irq = 0;
- cpu->carry = 0;
- cpu->overflow = 0;
- cpu->flagi = FALSE;
- cpu->cykle = 0;
-
- // reset will do the rest
- ARM7_HardReset (cpu);
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Power-ON reset. */
-void ARM7_HardReset (struct sARM7 *cpu)
- {
- // CPSR that makes sense
- cpu->Rx [ARM7_CPSR] = ARM7_CPSR_I | ARM7_CPSR_F | ARM7_CPSR_M_svc;
- Reset (cpu);
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Hardware reset via /RESET line. */
-void ARM7_SoftReset (struct sARM7 *cpu)
- {
- Reset (cpu);
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** CPSR update, possibly changing operating mode. */
-void ARM7_SetCPSR (struct sARM7 *cpu, ARM7_REG sr)
- {
- int stary, nowy;
-
- stary = s_tabTryb [ARM7_CPSR_M (cpu->Rx [ARM7_CPSR])];
- nowy = s_tabTryb [ARM7_CPSR_M (sr)];
- // do we have to change modes?
- if (nowy != stary)
- {
- // save this mode registers
- RX_BANK (stary, ARM7_SP) = cpu->Rx [ARM7_SP],
- RX_BANK (stary, ARM7_LR) = cpu->Rx [ARM7_LR],
- RX_BANK (stary, ARM7_SPSR) = cpu->Rx [ARM7_SPSR];
- if (stary == ARM7_MODE_fiq)
- {
- // copy R8-R12
- RX_BANK (ARM7_MODE_fiq, 8) = cpu->Rx [8],
- RX_BANK (ARM7_MODE_fiq, 9) = cpu->Rx [9],
- RX_BANK (ARM7_MODE_fiq, 10) = cpu->Rx [10],
- RX_BANK (ARM7_MODE_fiq, 11) = cpu->Rx [11],
- RX_BANK (ARM7_MODE_fiq, 12) = cpu->Rx [12];
- cpu->Rx [8] = RX_BANK (ARM7_MODE_usr, 8),
- cpu->Rx [9] = RX_BANK (ARM7_MODE_usr, 9),
- cpu->Rx [10] = RX_BANK (ARM7_MODE_usr, 10),
- cpu->Rx [11] = RX_BANK (ARM7_MODE_usr, 11),
- cpu->Rx [12] = RX_BANK (ARM7_MODE_usr, 12);
- }
-
- // fetch new mode registers
- cpu->Rx [ARM7_SP] = RX_BANK (nowy, ARM7_SP),
- cpu->Rx [ARM7_LR] = RX_BANK (nowy, ARM7_LR),
- cpu->Rx [ARM7_SPSR] = RX_BANK (nowy, ARM7_SPSR);
- if (nowy == ARM7_MODE_fiq)
- {
- // copy R8-R12
- RX_BANK (ARM7_MODE_usr, 8) = cpu->Rx [8],
- RX_BANK (ARM7_MODE_usr, 9) = cpu->Rx [9],
- RX_BANK (ARM7_MODE_usr, 10) = cpu->Rx [10],
- RX_BANK (ARM7_MODE_usr, 11) = cpu->Rx [11],
- RX_BANK (ARM7_MODE_usr, 12) = cpu->Rx [12];
- cpu->Rx [8] = RX_BANK (ARM7_MODE_fiq, 8),
- cpu->Rx [9] = RX_BANK (ARM7_MODE_fiq, 9),
- cpu->Rx [10] = RX_BANK (ARM7_MODE_fiq, 10),
- cpu->Rx [11] = RX_BANK (ARM7_MODE_fiq, 11),
- cpu->Rx [12] = RX_BANK (ARM7_MODE_fiq, 12);
- }
- }
-
- // new CPSR value
- cpu->Rx [ARM7_CPSR] = sr;
-
- // mode change could've enabled interrups, so we test for those and set
- // appropriate flag for the instruction loop to catch
- if (cpu->fiq)
- cpu->flagi |= ARM7_FL_FIQ;
-#ifndef ARM7_DREAMCAST
- if (cpu->irq)
- cpu->flagi |= ARM7_FL_IRQ;
-#endif
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Sets FIQ line state. */
-void ARM7_SetFIQ (struct sARM7 *cpu, int stan)
- {
- stan = stan ? TRUE : FALSE;
- // we catch changes only
- if (stan ^ cpu->fiq)
- {
- cpu->fiq = stan;
- if (cpu->fiq)
- cpu->flagi |= ARM7_FL_FIQ;
- }
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Sets IRQ line state. */
-void ARM7_SetIRQ (struct sARM7 *cpu, int stan)
- {
- stan = stan ? TRUE : FALSE;
- // we catch changes only
- if (stan ^ cpu->irq)
- {
- cpu->irq = stan;
- if (cpu->irq)
- cpu->flagi |= ARM7_FL_IRQ;
- }
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Tests for pending interrupts, switches to one if possible. */
-void ARM7_CheckIRQ (struct sARM7 *cpu)
- {
- UINT32 sr = cpu->Rx [ARM7_CPSR];
-
- // clear all interrupt flags
- cpu->flagi &= ~(ARM7_FL_FIQ | ARM7_FL_IRQ);
-
- // check for pending interrupts we can switch to
- // (FIQ can interrupt IRQ, but not the other way around)
- if (cpu->fiq)
- {
- if (!(sr & ARM7_CPSR_F))
- {
- // FIQ
- ARM7_SetCPSR (cpu, ARM7_CPSR_MX (sr, ARM7_CPSR_M_fiq) | ARM7_CPSR_F | ARM7_CPSR_I);
- cpu->Rx [ARM7_SPSR] = sr;
- // set new PC (return from interrupt will subtract 4)
- cpu->Rx [ARM7_LR] = cpu->Rx [ARM7_PC] + 4;
- cpu->Rx [ARM7_PC] = 0x0000001c;
- }
- }
-#ifndef ARM7_DREAMCAST
- if (cpu->irq)
- {
- if (!(sr & ARM7_CPSR_I))
- {
- // IRQ
- ARM7_SetCPSR (cpu, ARM7_CPSR_MX (sr, ARM7_CPSR_M_irq) | ARM7_CPSR_I);
- cpu->Rx [ARM7_SPSR] = sr;
- // set new PC (return from interrupt will subtract 4)
- cpu->Rx [ARM7_LR] = cpu->Rx [ARM7_PC] + 4;
- cpu->Rx [ARM7_PC] = 0x00000018;
- cpu->irq = 0;
- }
- }
-#endif
- }
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Single step. */
-void ARM7_Step (struct sARM7 *cpu)
-{
- // make a step
-#ifdef ARM7_THUMB
- if (cpu->Rx[ARM7_CPSR] & ARM7_CPSR_T)
- {
- ARM7i_Thumb_Step(cpu);
- }
- else
-#endif
- {
- ARM7i_Step (cpu);
- }
- // and test interrupts
- ARM7_CheckIRQ (cpu);
-}
- //--------------------------------------------------------------------------
-
- //--------------------------------------------------------------------------
- /** Runs emulation for at least n cycles, returns actual amount of cycles
- burned - normal interpreter. */
-int ARM7_Execute (struct sARM7 *cpu, int n)
- {
- cpu->cykle = 0;
- while (cpu->cykle < n)
- {
- ARM7_CheckIRQ (cpu);
- while (!cpu->flagi && cpu->cykle < n)
- // make one step, sum up cycles
- cpu->cykle += ARM7i_Step (cpu);
- }
- return cpu->cykle;
- }
- //--------------------------------------------------------------------------
-
-
- // private functions
-
-
- //--------------------------------------------------------------------------
- /** CPU Reset. */
-void Reset (struct sARM7 *cpu)
- {
- // clear ALU flags
- cpu->carry = 0;
- cpu->overflow = 0;
- // test CPSR mode and pick a valid one if necessary
- if (s_tabTryb [ARM7_CPSR_M (cpu->Rx [ARM7_CPSR])] < 0)
- cpu->Rx [ARM7_CPSR] = ARM7_CPSR_I | ARM7_CPSR_F | ARM7_CPSR_M_svc;
- // set up registers according to manual
- RX_BANK (ARM7_MODE_svc, ARM7_LR) = cpu->Rx [ARM7_PC];
- RX_BANK (ARM7_MODE_svc, ARM7_SPSR) = cpu->Rx [ARM7_CPSR];
- ARM7_SetCPSR (cpu, ARM7_CPSR_I | ARM7_CPSR_F | ARM7_CPSR_M_svc);
- cpu->Rx [ARM7_PC] = 0x00000000;
- }
- //--------------------------------------------------------------------------
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-07 18:16:04 +0000