4 media and vfp feature registers, mvfr0 and mvfr1, Table 12-5, Floating-point exception register bit functions -8 – ARM Cortex R4F User Manual

Page 349: Table 12-6, Mvfr0 register bit functions -8, Figure 12-5, Mvfr0 register format -8

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FPU Programmer’s Model

ARM DDI 0363E

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Table 12-5 shows how the bit values correspond with the FPEXC Register functions.

12.3.4

Media and VFP Feature Registers, MVFR0 and MVFR1

The VFP Feature Registers, MVFR0 and MVFR1, are read-only registers which describe the
features supported by the FPU. These registers are accessible in Privileged modes only.

Figure 12-5 shows the bit arrangement of the MVFR0 Register.

Figure 12-5 MVFR0 Register format

Table 12-6 shows how the bit values correspond with the MVFR0 Register functions.

Figure 12-6 on page 12-9 shows the bit arrangement of the MVFR1 Register.

Table 12-5 Floating-Point Exception Register bit functions

Bits

Field

Function

[31]

Reserved

RAZ.

[30]

EN

VFP enable bit. Setting EN enables VFP functionality. Reset clears EN.

[29]

DEX

Set when an Undefined exception is taken because of a vector instruction that would have been
executed if the processor supported vectors. This field is cleared when an Undefined exception is
taken for any other reason. Resets to zero.

[28:0]

Reserved

RAZ.

RB

SV

RM

TE

SP

SR

D

DP

31

28 27

24 23

20 19

16 15

12 11

8 7

4 3

0

Table 12-6 MVFR0 Register bit functions

Bits

Field

Function

[31:28]

RM

All VFP rounding modes supported:

0x1

[27:24]

SV

VFP short vector unsupported:

0x0

[23:20]

SR

VFP hardware square root supported:

0x1

[19:16]

D

VFP hardware divide supported:

0x1

[15:12]

TE

Only untrapped exception handling can be selected:

0x0

[11:8]

DP

Double precision supported in VFPv3:

0x2

[7:4]

SP

Single precision supported in VFPv3:

0x2

[3:0]

RB

16x64-bit media register bank supported:

0x1

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