From 33ab8f735d0979ef68d7202d3adbf28f1ae2aceb Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Mon, 22 Apr 2013 13:20:32 -0400 Subject: [PATCH] kvm: Add support for pseudo-ops on ARM This changeset adds support for m5 pseudo-ops when running in kvm-mode. Unfortunately, we can't trap the normal gem5 co-processor entry in KVM (it doesn't seem to be possible to trap accesses to non-existing co-processors). We therefore use BZJ instructions to cause a trap from virtualized mode into gem5. The BZJ instruction is becomes a normal branch to the gem5 fallback code when running in simulated mode, which means that this patch does not need to change the ARM ISA-specific code. Note: This requires a patched host kernel. --- src/cpu/kvm/arm_cpu.cc | 21 ++++++ src/cpu/kvm/arm_cpu.hh | 2 + util/m5/m5op_arm.S | 166 +++++++++++++++-------------------------- 3 files changed, 85 insertions(+), 104 deletions(-) diff --git a/src/cpu/kvm/arm_cpu.cc b/src/cpu/kvm/arm_cpu.cc index d1082c53e..e131202a4 100644 --- a/src/cpu/kvm/arm_cpu.cc +++ b/src/cpu/kvm/arm_cpu.cc @@ -49,6 +49,7 @@ #include "debug/Kvm.hh" #include "debug/KvmContext.hh" #include "debug/KvmInt.hh" +#include "sim/pseudo_inst.hh" using namespace ArmISA; @@ -310,6 +311,26 @@ ArmKvmCPU::updateThreadContext() updateTCStateMisc(); } +Tick +ArmKvmCPU::onKvmExitHypercall() +{ + ThreadContext *tc(getContext(0)); + const uint32_t reg_ip(tc->readIntRegFlat(INTREG_R12)); + const uint8_t func((reg_ip >> 8) & 0xFF); + const uint8_t subfunc(reg_ip & 0xFF); + + DPRINTF(Kvm, "KVM Hypercall: 0x%x/0x%x\n", func, subfunc); + const uint64_t ret(PseudoInst::pseudoInst(getContext(0), func, subfunc)); + + // Just set the return value using the KVM API instead of messing + // with the context. We could have used the context, but that + // would have required us to request a full context sync. + setOneReg(REG_CORE32(usr_regs.ARM_r0), ret & 0xFFFFFFFF); + setOneReg(REG_CORE32(usr_regs.ARM_r1), (ret >> 32) & 0xFFFFFFFF); + + return 0; +} + const ArmKvmCPU::RegIndexVector & ArmKvmCPU::getRegList() const { diff --git a/src/cpu/kvm/arm_cpu.hh b/src/cpu/kvm/arm_cpu.hh index 687cb48b1..786320cfd 100644 --- a/src/cpu/kvm/arm_cpu.hh +++ b/src/cpu/kvm/arm_cpu.hh @@ -94,6 +94,8 @@ class ArmKvmCPU : public BaseKvmCPU void updateKvmState(); void updateThreadContext(); + Tick onKvmExitHypercall(); + /** * Get a list of registers supported by getOneReg() and setOneReg(). */ diff --git a/util/m5/m5op_arm.S b/util/m5/m5op_arm.S index 7f43ef508..83bef6a84 100644 --- a/util/m5/m5op_arm.S +++ b/util/m5/m5op_arm.S @@ -40,122 +40,80 @@ * Authors: Nathan Binkert * Ali Saidi * Chander Sudanthi + * Andreas Sandberg */ .syntax unified #ifdef __thumb__ .thumb #endif -#define m5_op 0xEE - #include "m5ops.h" +.text + +.macro simple_op name, func, subfunc + .globl \name +\name: + /* First, try to trap into m5 using the m5-kvm hypercall + * hack. The bxj will become a branch to the fallback code + * if it is executed in the normal m5 environment. + */ + push {lr} + ldr lr, =1f + ldr ip, =((((\func) & 0xFF) << 8) | ((\subfunc) & 0xFF)) + bxj lr + pop {pc} + + /* Old-style m5 pseudo instruction using CP1 accesses */ +1: #ifdef __thumb__ -#define INST(op, ra, rb, func) \ - .short (((op) << 8) | (func)); \ - .short (((ra) << 12) | (0x1 << 8) | (0x1 << 4) | (rb)) -/* m5ops m5func */ -/* ra coproc 1 op=1 rb */ + .short 0xEE00 | \func + .short 0x0110 | (\subfunc << 12) #else #define INST(op, ra, rb, func) \ - .long (((op) << 24) | ((func) << 16) | ((ra) << 12) | (0x1 << 8) | (0x1 << 4) | (rb)) -/* m5ops m5func ra coproc 1 op=1 rb */ + .long (0xEE000110 | (\func << 16) | (\subfunc << 12) #endif + pop {pc} +.endm -#define LEAF(func) \ - .globl func; \ -func: - -#define RET \ - mov pc,lr - -#define END(func) \ - -#define SIMPLE_OP(_f, _o) \ - LEAF(_f) \ - _o; \ - RET; \ - END(_f) - -#define ARM INST(m5_op, 0, 0, arm_func) -#define QUIESCE INST(m5_op, 0, 0, quiesce_func) -#define QUIESCENS INST(m5_op, 0, 0, quiescens_func) -#define QUIESCECYC INST(m5_op, 0, 0, quiescecycle_func) -#define QUIESCETIME INST(m5_op, 0, 0, quiescetime_func) -#define RPNS INST(m5_op, 0, 0, rpns_func) -#define WAKE_CPU INST(m5_op, 0, 0, wakecpu_func) -#define M5EXIT INST(m5_op, 0, 0, exit_func) -#define INITPARAM INST(m5_op, 0, 0, initparam_func) -#define LOADSYMBOL INST(m5_op, 0, 0, loadsymbol_func) -#define RESET_STATS INST(m5_op, 0, 0, resetstats_func) -#define DUMP_STATS INST(m5_op, 0, 0, dumpstats_func) -#define DUMPRST_STATS INST(m5_op, 0, 0, dumprststats_func) -#define CHECKPOINT INST(m5_op, 0, 0, ckpt_func) -#define READFILE INST(m5_op, 0, 0, readfile_func) -#define WRITEFILE INST(m5_op, 0, 0, writefile_func) -#define DEBUGBREAK INST(m5_op, 0, 0, debugbreak_func) -#define SWITCHCPU INST(m5_op, 0, 0, switchcpu_func) -#define ADDSYMBOL INST(m5_op, 0, 0, addsymbol_func) -#define PANIC INST(m5_op, 0, 0, panic_func) -#define WORK_BEGIN INST(m5_op, 0, 0, work_begin_func) -#define WORK_END INST(m5_op, 0, 0, work_end_func) - -#define AN_BSM INST(m5_op, an_bsm, 0, annotate_func) -#define AN_ESM INST(m5_op, an_esm, 0, annotate_func) -#define AN_BEGIN INST(m5_op, an_begin, 0, annotate_func) -#define AN_END INST(m5_op, an_end, 0, annotate_func) -#define AN_Q INST(m5_op, an_q, 0, annotate_func) -#define AN_RQ INST(m5_op, an_rq, 0, annotate_func) -#define AN_DQ INST(m5_op, an_dq, 0, annotate_func) -#define AN_WF INST(m5_op, an_wf, 0, annotate_func) -#define AN_WE INST(m5_op, an_we, 0, annotate_func) -#define AN_WS INST(m5_op, an_ws, 0, annotate_func) -#define AN_SQ INST(m5_op, an_sq, 0, annotate_func) -#define AN_AQ INST(m5_op, an_aq, 0, annotate_func) -#define AN_PQ INST(m5_op, an_pq, 0, annotate_func) -#define AN_L INST(m5_op, an_l, 0, annotate_func) -#define AN_IDENTIFY INST(m5_op, an_identify, 0, annotate_func) -#define AN_GETID INST(m5_op, an_getid, 0, annotate_func) - -.text - -SIMPLE_OP(arm, ARM) -SIMPLE_OP(quiesce, QUIESCE) -SIMPLE_OP(quiesceNs, QUIESCENS) -SIMPLE_OP(quiesceCycle, QUIESCECYC) -SIMPLE_OP(quiesceTime, QUIESCETIME) -SIMPLE_OP(rpns, RPNS) -SIMPLE_OP(wakeCPU, WAKE_CPU) -SIMPLE_OP(m5_exit, M5EXIT) -SIMPLE_OP(m5_initparam, INITPARAM) -SIMPLE_OP(m5_loadsymbol, LOADSYMBOL) -SIMPLE_OP(m5_reset_stats, RESET_STATS) -SIMPLE_OP(m5_dump_stats, DUMP_STATS) -SIMPLE_OP(m5_dumpreset_stats, DUMPRST_STATS) -SIMPLE_OP(m5_checkpoint, CHECKPOINT) -SIMPLE_OP(m5_readfile, READFILE) -SIMPLE_OP(m5_writefile, WRITEFILE) -SIMPLE_OP(m5_debugbreak, DEBUGBREAK) -SIMPLE_OP(m5_switchcpu, SWITCHCPU) -SIMPLE_OP(m5_addsymbol, ADDSYMBOL) -SIMPLE_OP(m5_panic, PANIC) -SIMPLE_OP(m5_work_begin, WORK_BEGIN) -SIMPLE_OP(m5_work_end, WORK_END) +#define SIMPLE_OP(name, func, subfunc) simple_op name, func, subfunc -SIMPLE_OP(m5a_bsm, AN_BSM) -SIMPLE_OP(m5a_esm, AN_ESM) -SIMPLE_OP(m5a_begin, AN_BEGIN) -SIMPLE_OP(m5a_end, AN_END) -SIMPLE_OP(m5a_q, AN_Q) -SIMPLE_OP(m5a_rq, AN_RQ) -SIMPLE_OP(m5a_dq, AN_DQ) -SIMPLE_OP(m5a_wf, AN_WF) -SIMPLE_OP(m5a_we, AN_WE) -SIMPLE_OP(m5a_ws, AN_WS) -SIMPLE_OP(m5a_sq, AN_SQ) -SIMPLE_OP(m5a_aq, AN_AQ) -SIMPLE_OP(m5a_pq, AN_PQ) -SIMPLE_OP(m5a_l, AN_L) -SIMPLE_OP(m5a_identify, AN_IDENTIFY) -SIMPLE_OP(m5a_getid, AN_GETID) +SIMPLE_OP(arm, arm_func, 0) +SIMPLE_OP(quiesce, quiesce_func, 0) +SIMPLE_OP(quiesceNs, quiescens_func, 0) +SIMPLE_OP(quiesceCycle, quiescecycle_func, 0) +SIMPLE_OP(quiesceTime, quiescetime_func, 0) +SIMPLE_OP(rpns, rpns_func, 0) +SIMPLE_OP(wakeCPU, wakecpu_func, 0) +SIMPLE_OP(m5_exit, exit_func, 0) +SIMPLE_OP(m5_initparam, initparam_func, 0) +SIMPLE_OP(m5_loadsymbol, loadsymbol_func, 0) +SIMPLE_OP(m5_reset_stats, resetstats_func, 0) +SIMPLE_OP(m5_dump_stats, dumpstats_func, 0) +SIMPLE_OP(m5_dumpreset_stats, dumprststats_func, 0) +SIMPLE_OP(m5_checkpoint, ckpt_func, 0) +SIMPLE_OP(m5_readfile, readfile_func, 0) +SIMPLE_OP(m5_writefile, writefile_func, 0) +SIMPLE_OP(m5_debugbreak, debugbreak_func, 0) +SIMPLE_OP(m5_switchcpu, switchcpu_func, 0) +SIMPLE_OP(m5_addsymbol, addsymbol_func, 0) +SIMPLE_OP(m5_panic, panic_func, 0) +SIMPLE_OP(m5_work_begin, work_begin_func, 0) +SIMPLE_OP(m5_work_end, work_end_func, 0) +SIMPLE_OP(m5a_bsm, annotate_func, an_bsm) +SIMPLE_OP(m5a_esm, annotate_func, an_esm) +SIMPLE_OP(m5a_begin, annotate_func, an_begin) +SIMPLE_OP(m5a_end, annotate_func, an_end) +SIMPLE_OP(m5a_q, annotate_func, an_q) +SIMPLE_OP(m5a_rq, annotate_func, an_rq) +SIMPLE_OP(m5a_dq, annotate_func, an_dq) +SIMPLE_OP(m5a_wf, annotate_func, an_wf) +SIMPLE_OP(m5a_we, annotate_func, an_we) +SIMPLE_OP(m5a_ws, annotate_func, an_ws) +SIMPLE_OP(m5a_sq, annotate_func, an_sq) +SIMPLE_OP(m5a_aq, annotate_func, an_aq) +SIMPLE_OP(m5a_pq, annotate_func, an_pq) +SIMPLE_OP(m5a_l, annotate_func, an_l) +SIMPLE_OP(m5a_identify, annotate_func, an_identify) +SIMPLE_OP(m5a_getid, annotate_func, an_getid) -- 2.30.2