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| author | Gabe Black <gblack@eecs.umich.edu> | 2009-06-09 23:41:03 -0700 |
|---|---|---|
| committer | Gabe Black <gblack@eecs.umich.edu> | 2009-06-09 23:41:03 -0700 |
| commit | 3ff1e922c22dcc68274b16fcce080cd69b69b47b (patch) | |
| tree | 07342655b1b6418f950fa9edffe8ca64a90e8091 | |
| parent | 37ac2871d5a65dfa19b63c3bed9c6622d6b8b6c9 (diff) | |
| download | gem5-3ff1e922c22dcc68274b16fcce080cd69b69b47b.tar.xz | |
ARM: Add a cmpxchg implementation to the "comm page".
This implementation does what it's supposed to (I think), but it's not atomic
and doesn't have memory barriers like the kernel's version.
| -rw-r--r-- | src/arch/arm/linux/process.cc | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/src/arch/arm/linux/process.cc b/src/arch/arm/linux/process.cc index 620bcf116..bc6388b73 100644 --- a/src/arch/arm/linux/process.cc +++ b/src/arch/arm/linux/process.cc @@ -482,6 +482,18 @@ ArmLinuxProcess::startup() swiNeg1, sizeof(swiNeg1)); } + // This -should- be atomic, but I don't think all the support that we'd + // need is implemented. There should also be memory barriers around it. + uint8_t cmpxchg[] = + { + 0x00, 0x30, 0x92, 0xe5, //ldr r3, [r2] + 0x00, 0x30, 0x53, 0xe0, //subs r3, r3, r0 + 0x00, 0x10, 0x92, 0x05, //streq r1, [r2] + 0x03, 0x00, 0xa0, 0xe1, //mov r0, r3 + 0x0e, 0xf0, 0xa0, 0xe1 //usr_ret lr + }; + tc->getMemPort()->writeBlob(commPage + 0x0fc0, cmpxchg, sizeof(cmpxchg)); + uint8_t get_tls[] = { 0x08, 0x00, 0x9f, 0xe5, //ldr r0, [pc, #(16 - 8)] |