Peter Maydell | a3494d4 | 2020-08-03 12:18:47 +0100 | [diff] [blame] | 1 | # M-profile UserFault.NOCP exception handling |
| 2 | # |
| 3 | # Copyright (c) 2020 Linaro, Ltd |
| 4 | # |
| 5 | # This library is free software; you can redistribute it and/or |
| 6 | # modify it under the terms of the GNU Lesser General Public |
| 7 | # License as published by the Free Software Foundation; either |
| 8 | # version 2.1 of the License, or (at your option) any later version. |
| 9 | # |
| 10 | # This library is distributed in the hope that it will be useful, |
| 11 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | # Lesser General Public License for more details. |
| 14 | # |
| 15 | # You should have received a copy of the GNU Lesser General Public |
| 16 | # License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| 17 | |
| 18 | # |
| 19 | # This file is processed by scripts/decodetree.py |
| 20 | # |
| 21 | # For M-profile, the architecture specifies that NOCP UsageFaults |
| 22 | # should take precedence over UNDEF faults over the whole wide |
| 23 | # range of coprocessor-space encodings, with the exception of |
| 24 | # VLLDM and VLSTM. (Compare v8.1M IsCPInstruction() pseudocode and |
| 25 | # v8M Arm ARM rule R_QLGM.) This isn't mandatory for v8.0M but we choose |
| 26 | # to behave the same as v8.1M. |
| 27 | # This decode is handled before any others (and in particular before |
| 28 | # decoding FP instructions which are in the coprocessor space). |
| 29 | # If the coprocessor is not present or disabled then we will generate |
| 30 | # the NOCP exception; otherwise we let the insn through to the main decode. |
| 31 | |
Peter Maydell | 83ff3d6 | 2020-11-19 21:55:53 +0000 | [diff] [blame] | 32 | %vd_dp 22:1 12:4 |
| 33 | %vd_sp 12:4 22:1 |
| 34 | |
Peter Maydell | 5d2555a | 2020-10-19 16:12:53 +0100 | [diff] [blame] | 35 | &nocp cp |
| 36 | |
Peter Maydell | fa85673 | 2021-06-18 15:10:15 +0100 | [diff] [blame] | 37 | # M-profile VLDR/VSTR to sysreg |
| 38 | %vldr_sysreg 22:1 13:3 |
| 39 | %imm7_0x4 0:7 !function=times_4 |
| 40 | |
| 41 | &vldr_sysreg rn reg imm a w p |
| 42 | @vldr_sysreg .... ... . a:1 . . . rn:4 ... . ... .. ....... \ |
| 43 | reg=%vldr_sysreg imm=%imm7_0x4 &vldr_sysreg |
| 44 | |
Peter Maydell | a3494d4 | 2020-08-03 12:18:47 +0100 | [diff] [blame] | 45 | { |
| 46 | # Special cases which do not take an early NOCP: VLLDM and VLSTM |
Peter Maydell | fe6fa22 | 2020-11-19 21:56:09 +0000 | [diff] [blame] | 47 | VLLDM_VLSTM 1110 1100 001 l:1 rn:4 0000 1010 op:1 000 0000 |
Peter Maydell | 83ff3d6 | 2020-11-19 21:55:53 +0000 | [diff] [blame] | 48 | # VSCCLRM (new in v8.1M) is similar: |
| 49 | VSCCLRM 1110 1100 1.01 1111 .... 1011 imm:7 0 vd=%vd_dp size=3 |
| 50 | VSCCLRM 1110 1100 1.01 1111 .... 1010 imm:8 vd=%vd_sp size=2 |
Peter Maydell | a3494d4 | 2020-08-03 12:18:47 +0100 | [diff] [blame] | 51 | |
Peter Maydell | fa85673 | 2021-06-18 15:10:15 +0100 | [diff] [blame] | 52 | # FP system register accesses: these are a special case because accesses |
| 53 | # to FPCXT_NS succeed even if the FPU is disabled. We therefore need |
| 54 | # to handle them before the big NOCP blocks. Note that within these |
| 55 | # insns NOCP still has higher priority than UNDEFs; this is implemented |
| 56 | # by their returning 'false' for UNDEF so as to fall through into the |
| 57 | # NOCP check (in contrast to VLLDM etc, which call unallocated_encoding() |
| 58 | # for the UNDEFs there that must take precedence over NOCP.) |
| 59 | |
| 60 | VMSR_VMRS ---- 1110 111 l:1 reg:4 rt:4 1010 0001 0000 |
| 61 | |
| 62 | # P=0 W=0 is SEE "Related encodings", so split into two patterns |
| 63 | VLDR_sysreg ---- 110 1 . . w:1 1 .... ... 0 111 11 ....... @vldr_sysreg p=1 |
| 64 | VLDR_sysreg ---- 110 0 . . 1 1 .... ... 0 111 11 ....... @vldr_sysreg p=0 w=1 |
| 65 | VSTR_sysreg ---- 110 1 . . w:1 0 .... ... 0 111 11 ....... @vldr_sysreg p=1 |
| 66 | VSTR_sysreg ---- 110 0 . . 1 0 .... ... 0 111 11 ....... @vldr_sysreg p=0 w=1 |
| 67 | |
Peter Maydell | 5d2555a | 2020-10-19 16:12:53 +0100 | [diff] [blame] | 68 | NOCP 111- 1110 ---- ---- ---- cp:4 ---- ---- &nocp |
| 69 | NOCP 111- 110- ---- ---- ---- cp:4 ---- ---- &nocp |
| 70 | # From v8.1M onwards this range will also NOCP: |
| 71 | NOCP_8_1 111- 1111 ---- ---- ---- ---- ---- ---- &nocp cp=10 |
Peter Maydell | a3494d4 | 2020-08-03 12:18:47 +0100 | [diff] [blame] | 72 | } |