Mixed updates:

- isa => nexus
- flags
- GPL_MATH_EMULATE
- document breakage of non-GPL emulator since we use new compiler.
- break lines in paragraohs I touched so that sentenses start on new
  lines.

1 files changed, 27 insertions, 11 deletions

diff --git a/share/man/man4/man4.i386/npx.4 b/share/man/man4/man4.i386/npx.4
index 0fbdafe..e742e7c 100644
--- a/share/man/man4/man4.i386/npx.4
+++ b/share/man/man4/man4.i386/npx.4
@@ -37,9 +37,11 @@
 .Nm npx
 .Nd Numeric Processing Extension coprocessor and emulator
 .Sh SYNOPSIS
+.Cd "device npx0 at nexus? port IO_NPX flags 0x0 irq 13"
 .Cd "options MATH_EMULATE"
+.Cd "options GPL_MATH_EMULATE"
 .\" XXX this is awful hackery to get it to work right... -- cgd
-.Cd "device npx0 at isa? port IO_NPX irq 13"
+.\" What the heck does he mean? - cracauer
 .Sh DESCRIPTION
 The
 .Nm npx
@@ -57,20 +59,34 @@ coprocessors.  The
 driver is required for proper system functioning regardless
 of whether or not a NPX is present.
 .Pp
-If there is no NPX present in the system, the "MATH_EMULATE"
-option must be defined in the kernel configuration file.
-It will provide support for the instructions normally executed
-by the NPX.  If there is no NPX in the system and the kernel
-is not built with math emulation, the system will not boot.
+If there is no NPX present in the system, the "MATH_EMULATE" or
+"GPL_MATH_EMULATE" option must be defined in the kernel configuration
+file. 
+It will provide support for the instructions normally executed by the
+NPX.
+If there is no NPX in the system and the kernel is not built with math
+emulation, the system will not boot.
+.Pp
+For a description of the possible "flags" values see the LINT kernel
+configuration file.
 .Sh CAVEATS
 The emulator is much slower than the NPX coprocessor.
 This will result in poor floating-point math performance
 if the emulator must be used.
+.Pp
+The non-GPL emulator does not support the whole set of npx
+instructions.
+It is sufficient for booting and configuring a system, but it cannot
+support a system with normal workload unless care is taken to compile
+the whole system (including third-party packages) with compiler
+options that avoid the use of the non-emulated instructions.
 .Sh BUGS
-There are lots of them, especially on cheap motherboards.  In particular,
-some motherboards do not have the interrupt lines from the NPX to
-the CPU wired properly.  If this is the case, the emulator must be used
-if consistent system operation is desired.
+There are lots of them, especially on old cheap motherboards. 
+In particular, some motherboards do not have the interrupt lines from
+the NPX to the CPU wired properly.
+If this is the case, the emulator must be used if consistent system
+operation is desired.
 .Pp
-Emulation of the transcendental functions instructions is incorrect.
+Emulation of the transcendental functions instructions in the non-GPL
+emulator is incorrect.
 Emulation of other instructions is suspect.