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| author | Tommy Murphy <tommy_murphy@hotmail.com> | 2020-05-26 18:33:30 +0100 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-05-26 10:33:30 -0700 |
| commit | 95a8cd9b5d07501ac2243c61f331b092b1ea9894 (patch) | |
| tree | 2a20460816534b185ae6f91f3ba1b2ae2c91fe12 /src | |
| parent | 4f9e2d7171f3cad8d1a99dff3eee5ec5e6d8ea2b (diff) | |
| download | riscv-openocd-95a8cd9b5d07501ac2243c61f331b092b1ea9894.zip riscv-openocd-95a8cd9b5d07501ac2243c61f331b092b1ea9894.tar.gz riscv-openocd-95a8cd9b5d07501ac2243c61f331b092b1ea9894.tar.bz2 | |
Don't use MMU in M mode - https://github.com/riscv/riscv-openocd/issu… (#479)
* Don't use MMU in M mode - https://github.com/riscv/riscv-openocd/issues/474
* Updated code based on feedback from @timsifive
Diffstat (limited to 'src')
| -rw-r--r-- | src/target/riscv/riscv.c | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/src/target/riscv/riscv.c b/src/target/riscv/riscv.c index 4c3f8fd..192b8c5 100644 --- a/src/target/riscv/riscv.c +++ b/src/target/riscv/riscv.c @@ -1383,15 +1383,34 @@ static int riscv_mmu(struct target *target, int *enabled) if (riscv_rtos_enabled(target)) riscv_set_current_hartid(target, target->rtos->current_thread - 1); - riscv_reg_t value; - if (riscv_get_register(target, &value, GDB_REGNO_SATP) != ERROR_OK) { + /* Don't use MMU in explicit or effective M (machine) mode */ + riscv_reg_t priv; + if (riscv_get_register(target, &priv, GDB_REGNO_PRIV) != ERROR_OK) { + LOG_ERROR("Failed to read priv register."); + return ERROR_FAIL; + } + + riscv_reg_t mstatus; + if (riscv_get_register(target, &mstatus, GDB_REGNO_MSTATUS) != ERROR_OK) { + LOG_ERROR("Failed to read mstatus register."); + return ERROR_FAIL; + } + + if ((get_field(mstatus, MSTATUS_MPRV) ? get_field(mstatus, MSTATUS_MPP) : priv) == PRV_M) { + LOG_DEBUG("SATP/MMU ignored in Machine mode (mstatus=0x%" PRIx64 ").", mstatus); + *enabled = 0; + return ERROR_OK; + } + + riscv_reg_t satp; + if (riscv_get_register(target, &satp, GDB_REGNO_SATP) != ERROR_OK) { LOG_DEBUG("Couldn't read SATP."); /* If we can't read SATP, then there must not be an MMU. */ *enabled = 0; return ERROR_OK; } - if (get_field(value, RISCV_SATP_MODE(riscv_xlen(target))) == SATP_MODE_OFF) { + if (get_field(satp, RISCV_SATP_MODE(riscv_xlen(target))) == SATP_MODE_OFF) { LOG_DEBUG("MMU is disabled."); *enabled = 0; } else { |