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authorMaciej W. Rozycki <macro@linux-mips.org>2015-04-03 23:27:33 +0100
committerRalf Baechle <ralf@linux-mips.org>2015-04-08 01:10:28 +0200
commitc491cfa2ca804e58f4e88386736c1608c82da08a (patch)
tree4563578a985b1ceb09e067c76936510eeac6d4e8 /arch/mips/math-emu
parentf684362689ddc4a4e055be438d6416cc280a1372 (diff)
MIPS: math-emu: Implement the FCCR, FEXR and FENR registers
Implement the FCCR, FEXR and FENR "shadow" FPU registers for the architecture levels that include them, for the CFC1 and CTC1 instructions in the full emulation mode. For completeness add macros for the CP1 UFR and UNFR registers too, no actual implementation though. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9708/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/math-emu')
-rw-r--r--arch/mips/math-emu/cp1emu.c106
1 files changed, 91 insertions, 15 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index 7aa42b2caf89..8034ee4c3341 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -64,11 +64,14 @@ static int fpux_emu(struct pt_regs *,
/* Control registers */
#define FPCREG_RID 0 /* $0 = revision id */
+#define FPCREG_FCCR 25 /* $25 = fccr */
+#define FPCREG_FEXR 26 /* $26 = fexr */
+#define FPCREG_FENR 28 /* $28 = fenr */
#define FPCREG_CSR 31 /* $31 = csr */
/* convert condition code register number to csr bit */
const unsigned int fpucondbit[8] = {
- FPU_CSR_COND0,
+ FPU_CSR_COND,
FPU_CSR_COND1,
FPU_CSR_COND2,
FPU_CSR_COND3,
@@ -846,17 +849,53 @@ do { \
static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
mips_instruction ir)
{
- u32 value;
+ u32 fcr31 = ctx->fcr31;
+ u32 value = 0;
- if (MIPSInst_RD(ir) == FPCREG_CSR) {
- value = ctx->fcr31;
+ switch (MIPSInst_RD(ir)) {
+ case FPCREG_CSR:
+ value = fcr31;
pr_debug("%p gpr[%d]<-csr=%08x\n",
- (void *)xcp->cp0_epc,
- MIPSInst_RT(ir), value);
- } else if (MIPSInst_RD(ir) == FPCREG_RID)
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FENR:
+ if (!cpu_has_mips_r)
+ break;
+ value = (fcr31 >> (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
+ MIPS_FENR_FS;
+ value |= fcr31 & (FPU_CSR_ALL_E | FPU_CSR_RM);
+ pr_debug("%p gpr[%d]<-enr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FEXR:
+ if (!cpu_has_mips_r)
+ break;
+ value = fcr31 & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ pr_debug("%p gpr[%d]<-exr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FCCR:
+ if (!cpu_has_mips_r)
+ break;
+ value = (fcr31 >> (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
+ MIPS_FCCR_COND0;
+ value |= (fcr31 >> (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
+ (MIPS_FCCR_CONDX & ~MIPS_FCCR_COND0);
+ pr_debug("%p gpr[%d]<-ccr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_RID:
value = current_cpu_data.fpu_id;
- else
- value = 0;
+ break;
+
+ default:
+ break;
+ }
+
if (MIPSInst_RT(ir))
xcp->regs[MIPSInst_RT(ir)] = value;
}
@@ -867,6 +906,7 @@ static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
mips_instruction ir)
{
+ u32 fcr31 = ctx->fcr31;
u32 value;
if (MIPSInst_RT(ir) == 0)
@@ -874,16 +914,52 @@ static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
else
value = xcp->regs[MIPSInst_RT(ir)];
- /* we only have one writable control reg
- */
- if (MIPSInst_RD(ir) == FPCREG_CSR) {
+ switch (MIPSInst_RD(ir)) {
+ case FPCREG_CSR:
pr_debug("%p gpr[%d]->csr=%08x\n",
- (void *)xcp->cp0_epc,
- MIPSInst_RT(ir), value);
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
/* Don't write reserved bits. */
- ctx->fcr31 = value & ~FPU_CSR_RSVD;
+ fcr31 = value & ~FPU_CSR_RSVD;
+ break;
+
+ case FPCREG_FENR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->enr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_FS | FPU_CSR_ALL_E | FPU_CSR_RM);
+ fcr31 |= (value << (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
+ FPU_CSR_FS;
+ fcr31 |= value & (FPU_CSR_ALL_E | FPU_CSR_RM);
+ break;
+
+ case FPCREG_FEXR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->exr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ fcr31 |= value & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ break;
+
+ case FPCREG_FCCR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->ccr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_CONDX | FPU_CSR_COND);
+ fcr31 |= (value << (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
+ FPU_CSR_COND;
+ fcr31 |= (value << (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
+ FPU_CSR_CONDX;
+ break;
+
+ default:
+ break;
}
+
+ ctx->fcr31 = fcr31;
}
/*