From 8132c01830c9e71e75e6bc1e365326cf07c5b00f Mon Sep 17 00:00:00 2001 From: Kevin Hartman Date: Mon, 5 Jan 2015 02:17:00 -0500 Subject: Added exclusive reservation granule from ARMv7 spec to dyncom to protect LDR/STREX. --- src/core/arm/dyncom/arm_dyncom_interpreter.cpp | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'src/core/arm/dyncom/arm_dyncom_interpreter.cpp') diff --git a/src/core/arm/dyncom/arm_dyncom_interpreter.cpp b/src/core/arm/dyncom/arm_dyncom_interpreter.cpp index 64335b9c..ba23ef38 100644 --- a/src/core/arm/dyncom/arm_dyncom_interpreter.cpp +++ b/src/core/arm/dyncom/arm_dyncom_interpreter.cpp @@ -63,16 +63,21 @@ extern void switch_mode(arm_core_t *core, uint32_t mode); typedef arm_core_t arm_processor; typedef unsigned int (*shtop_fp_t)(arm_processor *cpu, unsigned int sht_oper); +// Defines a reservation granule of 2 words, which protects the first 2 words starting at the tag. +// This is the smallest granule allowed by the v7 spec, and is coincidentally just large enough to +// support LDR/STREXD. +static const ARMword RESERVATION_GRANULE_MASK = 0xFFFFFFF8; + // Exclusive memory access static int exclusive_detect(ARMul_State* state, ARMword addr){ - if(state->exclusive_tag == addr) + if(state->exclusive_tag == (addr & RESERVATION_GRANULE_MASK)) return 0; else return -1; } static void add_exclusive_addr(ARMul_State* state, ARMword addr){ - state->exclusive_tag = addr; + state->exclusive_tag = addr & RESERVATION_GRANULE_MASK; return; } @@ -80,7 +85,6 @@ static void remove_exclusive(ARMul_State* state, ARMword addr){ state->exclusive_tag = 0xFFFFFFFF; } - unsigned int DPO(Immediate)(arm_processor *cpu, unsigned int sht_oper) { unsigned int immed_8 = BITS(sht_oper, 0, 7); unsigned int rotate_imm = BITS(sht_oper, 8, 11); @@ -4551,7 +4555,6 @@ unsigned InterpreterMainLoop(ARMul_State* state) { add_exclusive_addr(cpu, read_addr); cpu->exclusive_state = 1; - // TODO(bunnei): Do we need to also make [read_addr + 4] exclusive? RD = Memory::Read32(read_addr); RD2 = Memory::Read32(read_addr + 4); @@ -5978,7 +5981,6 @@ unsigned InterpreterMainLoop(ARMul_State* state) { if ((exclusive_detect(cpu, write_addr) == 0) && (cpu->exclusive_state == 1)) { remove_exclusive(cpu, write_addr); cpu->exclusive_state = 0; - // TODO(bunnei): Remove exclusive from [write_addr + 4] if we implement this in LDREXD Memory::Write32(write_addr, cpu->Reg[inst_cream->Rm]); Memory::Write32(write_addr + 4, cpu->Reg[inst_cream->Rm + 1]); -- cgit v1.2.3