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| author | Nicholas Piggin <npiggin@gmail.com> | 2024-12-19 13:40:35 +1000 |
|---|---|---|
| committer | Nicholas Piggin <npiggin@gmail.com> | 2025-03-11 22:43:32 +1000 |
| commit | d8a624515a9773cb9d7afd47926bd64ae8fa0fc6 (patch) | |
| tree | e27039aa23d07a702ccb504b91285cec21fbbf18 | |
| parent | e8291ec16da80566c121c68d9112be458954d90b (diff) | |
| download | focaccia-qemu-d8a624515a9773cb9d7afd47926bd64ae8fa0fc6.tar.gz focaccia-qemu-d8a624515a9773cb9d7afd47926bd64ae8fa0fc6.zip | |
target/ppc: Wire up BookE ATB registers for e500 family
From the Freescale PowerPC Architecture Primer: Alternate time base APU. This APU, implemented on the e500v2, defines a 64-bit time base counter that differs from the PowerPC defined time base in that it is not writable and counts at a different, and typically much higher, frequency. The alternate time base always counts up, wrapping when the 64-bit count overflows. This implementation of ATB uses the same frequency as the TB. The existing spr_read_atbu/l functions are unused without this patch to wire them into the SPR. RTEMS uses this SPR on the e6500, though this hasn't been tested. Message-ID: <20241219034035.1826173-6-npiggin@gmail.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
| -rw-r--r-- | target/ppc/cpu_init.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c index 9dc5ace828..8b590e7f17 100644 --- a/target/ppc/cpu_init.c +++ b/target/ppc/cpu_init.c @@ -922,6 +922,18 @@ static void register_BookE206_sprs(CPUPPCState *env, uint32_t mas_mask, #endif } +static void register_atb_sprs(CPUPPCState *env) +{ + spr_register(env, SPR_ATBL, "ATBL", + &spr_read_atbl, SPR_NOACCESS, + &spr_read_atbl, SPR_NOACCESS, + 0x00000000); + spr_register(env, SPR_ATBU, "ATBU", + &spr_read_atbu, SPR_NOACCESS, + &spr_read_atbu, SPR_NOACCESS, + 0x00000000); +} + /* SPR specific to PowerPC 440 implementation */ static void register_440_sprs(CPUPPCState *env) { @@ -2911,6 +2923,11 @@ static void init_proc_e500(CPUPPCState *env, int version) register_BookE206_sprs(env, 0x000000DF, tlbncfg, mmucfg); register_usprgh_sprs(env); + if (version != fsl_e500v1) { + /* e500v1 has no support for alternate timebase */ + register_atb_sprs(env); + } + spr_register(env, SPR_HID0, "HID0", SPR_NOACCESS, SPR_NOACCESS, &spr_read_generic, &spr_write_generic, |