From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> commit 6288b4ceca868eac4bf729532f8d845e3ecbed98 upstream. TRCPROCSELR is not implemented if the TRCIDR3.NUMPROC == 0. Skip accessing the register in such cases. Cc: stable@xxxxxxxxxxxxxxx Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Cc: Mike Leach <mike.leach@xxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Link: https://lore.kernel.org/r/20201127175256.1092685-7-mathieu.poirier@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hwtracing/coresight/coresight-etm4x-core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -124,8 +124,8 @@ static int etm4_enable_hw(struct etmv4_d if (coresight_timeout(drvdata->base, TRCSTATR, TRCSTATR_IDLE_BIT, 1)) dev_err(etm_dev, "timeout while waiting for Idle Trace Status\n"); - - writel_relaxed(config->pe_sel, drvdata->base + TRCPROCSELR); + if (drvdata->nr_pe) + writel_relaxed(config->pe_sel, drvdata->base + TRCPROCSELR); writel_relaxed(config->cfg, drvdata->base + TRCCONFIGR); /* nothing specific implemented */ writel_relaxed(0x0, drvdata->base + TRCAUXCTLR); @@ -1180,7 +1180,8 @@ static int etm4_cpu_save(struct etmv4_dr state = drvdata->save_state; state->trcprgctlr = readl(drvdata->base + TRCPRGCTLR); - state->trcprocselr = readl(drvdata->base + TRCPROCSELR); + if (drvdata->nr_pe) + state->trcprocselr = readl(drvdata->base + TRCPROCSELR); state->trcconfigr = readl(drvdata->base + TRCCONFIGR); state->trcauxctlr = readl(drvdata->base + TRCAUXCTLR); state->trceventctl0r = readl(drvdata->base + TRCEVENTCTL0R); @@ -1287,7 +1288,8 @@ static void etm4_cpu_restore(struct etmv writel_relaxed(state->trcclaimset, drvdata->base + TRCCLAIMSET); writel_relaxed(state->trcprgctlr, drvdata->base + TRCPRGCTLR); - writel_relaxed(state->trcprocselr, drvdata->base + TRCPROCSELR); + if (drvdata->nr_pe) + writel_relaxed(state->trcprocselr, drvdata->base + TRCPROCSELR); writel_relaxed(state->trcconfigr, drvdata->base + TRCCONFIGR); writel_relaxed(state->trcauxctlr, drvdata->base + TRCAUXCTLR); writel_relaxed(state->trceventctl0r, drvdata->base + TRCEVENTCTL0R);