aboutsummaryrefslogtreecommitdiff
path: root/target/m68k/cpu.h
diff options
context:
space:
mode:
authorLucien Murray-Pitts <lucienmp.qemu@gmail.com>2021-02-01 01:01:52 +0100
committerLaurent Vivier <laurent@vivier.eu>2021-02-11 21:10:01 +0100
commitee2fc6c6da8b2d6f961c8559d62e990c65f67736 (patch)
tree55000e420b2249ed59891546d7ddc316e7b063d0 /target/m68k/cpu.h
parent5b19cb63d9dfda41b412373b8c9fe14641bcab60 (diff)
downloadqemu-arm-ee2fc6c6da8b2d6f961c8559d62e990c65f67736.tar.gz
m68k: improve cpu instantiation comments
Improvement in comments for the instantiation functions. This is to highlight what each cpu class, in the 68000 series, contains in terms of instructions/features. Signed-off-by: Lucien Murray-Pitts <lucienmp.qemu@gmail.com> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu> Message-Id: <2dfe32672ee6ddce4b54c6bcfce579d35abeaf51.1612137712.git.balaton@eik.bme.hu> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'target/m68k/cpu.h')
-rw-r--r--target/m68k/cpu.h49
1 files changed, 29 insertions, 20 deletions
diff --git a/target/m68k/cpu.h b/target/m68k/cpu.h
index de5b9875fe..1d59cbb3f4 100644
--- a/target/m68k/cpu.h
+++ b/target/m68k/cpu.h
@@ -450,39 +450,48 @@ void m68k_switch_sp(CPUM68KState *env);
void do_m68k_semihosting(CPUM68KState *env, int nr);
/*
+ * The 68000 family is defined in six main CPU classes, the 680[012346]0.
+ * Generally each successive CPU adds enhanced data/stack/instructions.
+ * However, some features are only common to one, or a few classes.
+ * The features covers those subsets of instructons.
+ *
+ * CPU32/32+ are basically 680010 compatible with some 68020 class instructons,
+ * and some additional CPU32 instructions. Mostly Supervisor state differences.
+ *
+ * The ColdFire core ISA is a RISC-style reduction of the 68000 series cpu.
* There are 4 ColdFire core ISA revisions: A, A+, B and C.
* Each feature covers the subset of instructions common to the
* ISA revisions mentioned.
*/
enum m68k_features {
- M68K_FEATURE_M68000,
+ M68K_FEATURE_M68000, /* Base m68k instruction set */
M68K_FEATURE_M68020,
M68K_FEATURE_M68030,
M68K_FEATURE_M68040,
M68K_FEATURE_M68060,
- M68K_FEATURE_CF_ISA_A,
- M68K_FEATURE_CF_ISA_B, /* (ISA B or C). */
- M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C). */
- M68K_FEATURE_BRAL, /* Long unconditional branch. (ISA A+ or B). */
+ M68K_FEATURE_CF_ISA_A, /* Base Coldfire set Rev A. */
+ M68K_FEATURE_CF_ISA_B, /* (ISA B or C). */
+ M68K_FEATURE_CF_ISA_APLUSC, /* BIT/BITREV, FF1, STRLDSR (ISA A+ or C). */
+ M68K_FEATURE_BRAL, /* BRA with Long branch. (680[2346]0, ISA A+ or B). */
M68K_FEATURE_CF_FPU,
M68K_FEATURE_CF_MAC,
M68K_FEATURE_CF_EMAC,
- M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate). */
- M68K_FEATURE_USP, /* User Stack Pointer. (ISA A+, B or C). */
- M68K_FEATURE_EXT_FULL, /* 68020+ full extension word. */
- M68K_FEATURE_WORD_INDEX, /* word sized address index registers. */
- M68K_FEATURE_SCALED_INDEX, /* scaled address index registers. */
- M68K_FEATURE_LONG_MULDIV, /* 32 bit multiply/divide. */
- M68K_FEATURE_QUAD_MULDIV, /* 64 bit multiply/divide. */
- M68K_FEATURE_BCCL, /* Long conditional branches. */
- M68K_FEATURE_BITFIELD, /* Bit field insns. */
- M68K_FEATURE_FPU,
- M68K_FEATURE_CAS,
- M68K_FEATURE_BKPT,
- M68K_FEATURE_RTD,
- M68K_FEATURE_CHK2,
- M68K_FEATURE_MOVEP,
+ M68K_FEATURE_CF_EMAC_B, /* Revision B EMAC (dual accumulate). */
+ M68K_FEATURE_USP, /* User Stack Pointer. (680[012346]0, ISA A+, B or C).*/
+ M68K_FEATURE_EXT_FULL, /* 68020+ full extension word. */
+ M68K_FEATURE_WORD_INDEX, /* word sized address index registers. */
+ M68K_FEATURE_SCALED_INDEX, /* scaled address index registers. */
+ M68K_FEATURE_LONG_MULDIV, /* 32 bit mul/div. (680[2346]0, and CPU32) */
+ M68K_FEATURE_QUAD_MULDIV, /* 64 bit mul/div. (680[2346]0, and CPU32) */
+ M68K_FEATURE_BCCL, /* Bcc with Long branches. (680[2346]0, and CPU32) */
+ M68K_FEATURE_BITFIELD, /* BFxxx Bit field insns. (680[2346]0) */
+ M68K_FEATURE_FPU, /* fpu insn. (680[46]0) */
+ M68K_FEATURE_CAS, /* CAS/CAS2[WL] insns. (680[2346]0) */
+ M68K_FEATURE_BKPT, /* BKPT insn. (680[12346]0, and CPU32) */
+ M68K_FEATURE_RTD, /* RTD insn. (680[12346]0, and CPU32) */
+ M68K_FEATURE_CHK2, /* CHK2 insn. (680[2346]0, and CPU32) */
+ M68K_FEATURE_MOVEP, /* MOVEP insn. (680[01234]0, and CPU32) */
};
static inline int m68k_feature(CPUM68KState *env, int feature)