Re: [PATCH] coresight: etm4x: Fix accesses to TRCSEQRSTEVR and TRCSEQSTR

From: Anshuman Khandual
Date: Wed Jan 11 2023 - 22:49:04 EST




On 1/10/23 18:21, Junhao He wrote:
> The TRCSEQRSTEVR and TRCSEQSTR register is not implemented if the

s/register is/registers are/

> TRCIDR5.NUMSEQSTATE == 0. Skip accessing the register in such cases.

s/register/registers/

>
> Signed-off-by: Junhao He <hejunhao3@xxxxxxxxxx>

Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

> ---
> .../hwtracing/coresight/coresight-etm4x-core.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 80fefaba58ee..c7a65d1524fc 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -424,8 +424,10 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
> etm4x_relaxed_write32(csa, config->vipcssctlr, TRCVIPCSSCTLR);
> for (i = 0; i < drvdata->nrseqstate - 1; i++)
> etm4x_relaxed_write32(csa, config->seq_ctrl[i], TRCSEQEVRn(i));
> - etm4x_relaxed_write32(csa, config->seq_rst, TRCSEQRSTEVR);
> - etm4x_relaxed_write32(csa, config->seq_state, TRCSEQSTR);
> + if (drvdata->nrseqstate) {
> + etm4x_relaxed_write32(csa, config->seq_rst, TRCSEQRSTEVR);
> + etm4x_relaxed_write32(csa, config->seq_state, TRCSEQSTR);
> + }
> etm4x_relaxed_write32(csa, config->ext_inp, TRCEXTINSELR);
> for (i = 0; i < drvdata->nr_cntr; i++) {
> etm4x_relaxed_write32(csa, config->cntrldvr[i], TRCCNTRLDVRn(i));
> @@ -1631,8 +1633,10 @@ static int __etm4_cpu_save(struct etmv4_drvdata *drvdata)
> for (i = 0; i < drvdata->nrseqstate - 1; i++)
> state->trcseqevr[i] = etm4x_read32(csa, TRCSEQEVRn(i));
>
> - state->trcseqrstevr = etm4x_read32(csa, TRCSEQRSTEVR);
> - state->trcseqstr = etm4x_read32(csa, TRCSEQSTR);
> + if (drvdata->nrseqstate) {
> + state->trcseqrstevr = etm4x_read32(csa, TRCSEQRSTEVR);
> + state->trcseqstr = etm4x_read32(csa, TRCSEQSTR);
> + }
> state->trcextinselr = etm4x_read32(csa, TRCEXTINSELR);
>
> for (i = 0; i < drvdata->nr_cntr; i++) {
> @@ -1760,8 +1764,10 @@ static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata)
> for (i = 0; i < drvdata->nrseqstate - 1; i++)
> etm4x_relaxed_write32(csa, state->trcseqevr[i], TRCSEQEVRn(i));
>
> - etm4x_relaxed_write32(csa, state->trcseqrstevr, TRCSEQRSTEVR);
> - etm4x_relaxed_write32(csa, state->trcseqstr, TRCSEQSTR);
> + if (drvdata->nrseqstate) {
> + etm4x_relaxed_write32(csa, state->trcseqrstevr, TRCSEQRSTEVR);
> + etm4x_relaxed_write32(csa, state->trcseqstr, TRCSEQSTR);
> + }
> etm4x_relaxed_write32(csa, state->trcextinselr, TRCEXTINSELR);
>
> for (i = 0; i < drvdata->nr_cntr; i++) {