12003-03-22 Ralph Siemsen <ralphs@netwinder.org> 2 * Reformat all but softfloat files to get a consistent coding style. 3 Used "indent -kr -i8 -ts8 -sob -l132 -ss" and a few manual fixups. 4 * Removed dead code and fixed function protypes to match definitions. 5 * Consolidated use of (opcode && MASK_ARITHMETIC_OPCODE) >> 20. 6 * Make 80-bit precision a compile-time option. (1%) 7 * Only initialize FPE state once in repeat-FP situations. (6%) 8 92002-01-19 Russell King <rmk@arm.linux.org.uk> 10 11 * fpa11.h - Add documentation 12 - remove userRegisters pointer from this structure. 13 - add new method to obtain integer register values. 14 * softfloat.c - Remove float128 15 * softfloat.h - Remove float128 16 * softfloat-specialize - Remove float128 17 18 * The FPA11 structure is not a kernel-specific data structure. 19 It is used by users of ptrace to examine the values of the 20 floating point registers. Therefore, any changes to the 21 FPA11 structure (size or position of elements contained 22 within) have to be well thought out. 23 24 * Since 128-bit float requires the FPA11 structure to change 25 size, it has been removed. 128-bit float is currently unused, 26 and needs various things to be re-worked so that we won't 27 overflow the available space in the task structure. 28 29 * The changes are designed to break any patch that goes on top 30 of this code, so that the authors properly review their changes. 31 321999-08-19 Scott Bambrough <scottb@netwinder.org> 33 34 * fpmodule.c - Changed version number to 0.95 35 * fpa11.h - modified FPA11, FPREG structures 36 * fpa11.c - Changes due to FPA11, FPREG structure alterations. 37 * fpa11_cpdo.c - Changes due to FPA11, FPREG structure alterations. 38 * fpa11_cpdt.c - Changes due to FPA11, FPREG structure alterations. 39 * fpa11_cprt.c - Changes due to FPA11, FPREG structure alterations. 40 * single_cpdo.c - Changes due to FPA11, FPREG structure alterations. 41 * double_cpdo.c - Changes due to FPA11, FPREG structure alterations. 42 * extended_cpdo.c - Changes due to FPA11, FPREG structure alterations. 43 44 * I discovered several bugs. First and worst is that the kernel 45 passes in a pointer to the FPE's state area. This is defined 46 as a struct user_fp (see user.h). This pointer was cast to a 47 FPA11*. Unfortunately FPA11 and user_fp are of different sizes; 48 user_fp is smaller. This meant that the FPE scribbled on things 49 below its area, which is bad, as the area is in the thread_struct 50 embedded in the process task structure. Thus we were scribbling 51 over one of the most important structures in the entire OS. 52 53 * user_fp and FPA11 have now been harmonized. Most of the changes 54 in the above code were dereferencing problems due to moving the 55 register type out of FPREG, and getting rid of the union variable 56 fpvalue. 57 58 * Second I noticed resetFPA11 was not always being called for a 59 task. This should happen on the first floating point exception 60 that occurs. It is controlled by init_flag in FPA11. The 61 comment in the code beside init_flag state the kernel guarantees 62 this to be zero. Not so. I found that the kernel recycles task 63 structures, and that recycled ones may not have init_flag zeroed. 64 I couldn't even find anything that guarantees it is zeroed when 65 when the task structure is initially allocated. In any case 66 I now initialize the entire FPE state in the thread structure to 67 zero when allocated and recycled. See alloc_task_struct() and 68 flush_thread() in arch/arm/process.c. The change to 69 alloc_task_struct() may not be necessary, but I left it in for 70 completeness (better safe than sorry). 71 721998-11-23 Scott Bambrough <scottb@netwinder.org> 73 74 * README.FPE - fix typo in description of lfm/sfm instructions 75 * NOTES - Added file to describe known bugs/problems 76 * fpmodule.c - Changed version number to 0.94 77 781998-11-20 Scott Bambrough <scottb@netwinder.org> 79 80 * README.FPE - fix description of URD, NRM instructions 81 * TODO - remove URD, NRM instructions from TODO list 82 * single_cpdo.c - implement URD, NRM 83 * double_cpdo.c - implement URD, NRM 84 * extended_cpdo.c - implement URD, NRM 85 861998-11-19 Scott Bambrough <scottb@netwinder.org> 87 88 * ChangeLog - Added this file to track changes made. 89 * fpa11.c - added code to initialize register types to typeNone 90 * fpa11_cpdt.c - fixed bug in storeExtended (typeExtended changed to 91 typeDouble in switch statement) 92