diff --git a/src/target/cortex_a.c b/src/target/cortex_a.c index 61a5df389..3f00511c2 100644 --- a/src/target/cortex_a.c +++ b/src/target/cortex_a.c @@ -132,35 +132,35 @@ static int cortex_a_mmu_modify(struct target *target, int enable) struct cortex_a_common *cortex_a = target_to_cortex_a(target); struct armv7a_common *armv7a = target_to_armv7a(target); int retval = ERROR_OK; + int need_write = 0; + if (enable) { /* if mmu enabled at target stop and mmu not enable */ if (!(cortex_a->cp15_control_reg & 0x1U)) { LOG_ERROR("trying to enable mmu on target stopped with mmu disable"); return ERROR_FAIL; } - if (!(cortex_a->cp15_control_reg_curr & 0x1U)) { + if ((cortex_a->cp15_control_reg_curr & 0x1U) == 0) { cortex_a->cp15_control_reg_curr |= 0x1U; - retval = armv7a->arm.mcr(target, 15, - 0, 0, /* op1, op2 */ - 1, 0, /* CRn, CRm */ - cortex_a->cp15_control_reg_curr); + need_write = 1; } } else { - if ((cortex_a->cp15_control_reg_curr & 0x1U)) { - if (cortex_a->cp15_control_reg_curr & 0x4U) { - /* data cache is active */ - cortex_a->cp15_control_reg_curr &= ~0x4U; - /* flush data cache armv7 function to be called */ - if (armv7a->armv7a_mmu.armv7a_cache.flush_all_data_cache) - armv7a->armv7a_mmu.armv7a_cache.flush_all_data_cache(target); - } + if ((cortex_a->cp15_control_reg_curr & 0x1U) == 0x1U) { cortex_a->cp15_control_reg_curr &= ~0x1U; - retval = armv7a->arm.mcr(target, 15, - 0, 0, /* op1, op2 */ - 1, 0, /* CRn, CRm */ - cortex_a->cp15_control_reg_curr); + need_write = 1; } } + + if (need_write) { + LOG_DEBUG("%s, writing cp15 ctrl: %" PRIx32, + enable ? "enable mmu" : "disable mmu", + cortex_a->cp15_control_reg_curr); + + retval = armv7a->arm.mcr(target, 15, + 0, 0, /* op1, op2 */ + 1, 0, /* CRn, CRm */ + cortex_a->cp15_control_reg_curr); + } return retval; }