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dsp: enable integrated DSP in SR at startup

This commit is contained in:
Lephe 2020-07-28 18:11:02 +02:00
parent bc575f1599
commit e63ff8351b
Signed by: Lephenixnoir
GPG Key ID: 1BBA026E13FC0495
3 changed files with 76 additions and 12 deletions
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27
src/kernel/cpu.h
View File

@ -36,4 +36,31 @@ void cpu_setCPUOPM(uint32_t CPUOPM);
/* cpu_getCPUOPM(): Get the CPU OperatioN Mode register */
uint32_t cpu_getCPUOPM(void);
//---
// Status Register
//---
/* Status Register bits */
typedef lword_union(sr_t,
uint32_t :1;
uint32_t MD :1;
uint32_t RB :1;
uint32_t BL :1;
uint32_t RC :12;
uint32_t :3;
uint32_t DSP :1;
uint32_t DMY :1;
uint32_t DMX :1;
uint32_t M :1;
uint32_t Q :1;
uint32_t IMASK :4;
uint32_t RF :2;
uint32_t S :1;
uint32_t T :1;
);
/* Get and set sr through the sr_t type */
sr_t cpu_getSR(void);
void cpu_setSR(sr_t sr);
#endif /* GINT_CORE_CPU */

38
src/kernel/cpu.s
View File

@ -5,21 +5,23 @@
.global _cpu_setVBR
.global _cpu_setCPUOPM
.global _cpu_getCPUOPM
.global _cpu_getSR
.global _cpu_setSR
/* cpu_setVBR(): Change VBR address */
.section .gint.mapped, "ax"
_cpu_setVBR_reloc:
mov.l r8, @-r15
mov.l r9, @-r15
sts.l pr, @-r15
stc.l sr, @-r15
/* Block all interrupts by setting IMASK=15 */
mov #0xf, r1
shll2 r1
shll2 r1
mov #0xf, r9
shll2 r9
shll2 r9
stc sr, r0
or r1, r0
or r9, r0
ldc r0, sr
/* Set the new VBR address */
@ -30,10 +32,17 @@ _cpu_setVBR_reloc:
jsr @r5
mov r6, r4
/* Enable interrupts again by restoring the status register */
ldc.l @r15+, sr
lds.l @r15+, pr
/* Enable interrupts again */
stc sr, r0
not r9, r9
and r9, r0
ldc r0, sr
/* Return the previous VBR address */
mov r8, r0
lds.l @r15+, pr
mov.l @r15+, r9
rts
mov.l @r15+, r8
@ -68,5 +77,16 @@ _cpu_getCPUOPM:
mov.l @r0, r0
.align 4
1: .long 0xff2f0000
/* cpu_getSR(): Get status register */
_cpu_getSR:
stc sr, r0
rts
nop
/* cpu_setSR(): Set status register */
_cpu_setSR:
ldc r4, sr
rts
nop

23
src/kernel/kernel.c
View File

@ -22,6 +22,7 @@ static void kinit_cpu(void);
typedef struct
{
sr_t SR;
uint32_t VBR;
uint32_t CPUOPM;
} ctx_t;
@ -31,11 +32,19 @@ GBSS static ctx_t sys_ctx, gint_ctx;
static void ctx_save(ctx_t *ctx)
{
if(isSH4()) ctx->CPUOPM = cpu_getCPUOPM();
if(isSH4())
{
ctx->CPUOPM = cpu_getCPUOPM();
ctx->SR = cpu_getSR();
}
}
static void ctx_restore(ctx_t *ctx)
{
if(isSH4()) cpu_setCPUOPM(ctx->CPUOPM);
if(isSH4())
{
cpu_setCPUOPM(ctx->CPUOPM);
cpu_setSR(ctx->SR);
}
}
//---
@ -99,7 +108,15 @@ static void drivers_switch(int who)
static void kinit_cpu(void)
{
if(isSH4()) cpu_setCPUOPM(cpu_getCPUOPM() | 0x00000008);
if(isSH4())
{
cpu_setCPUOPM(cpu_getCPUOPM() | 0x00000008);
/* Enable DSP mode on the CPU */
sr_t SR = cpu_getSR();
SR.DSP = 1;
cpu_setSR(SR);
}
}
/* kinit(): Install and start gint */