On 14 April 2016 at 11:11, Suzuki K Poulose <suzuki.poul...@arm.com> wrote:
> On 12/04/16 18:54, Mathieu Poirier wrote:
>>
>> In their current implementation the tmc_read_prepare/unprepare()
>> are a lump of if/else that is difficult to read. This patch is
>> alleviating that by using a switch statement. The latter also
>> allows for a better control on the error path.
>>
>> Signed-off-by: Mathieu Poirier <mathieu.poir...@linaro.org>
>> ---
>> drivers/hwtracing/coresight/coresight-tmc.c | 56
>> ++++++++++++++++++-----------
>> 1 file changed, 36 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-tmc.c
>> b/drivers/hwtracing/coresight/coresight-tmc.c
>> index 66fa7736d12f..d211aeec49f8 100644
>> --- a/drivers/hwtracing/coresight/coresight-tmc.c
>> +++ b/drivers/hwtracing/coresight/coresight-tmc.c
>> @@ -431,7 +431,7 @@ static const struct coresight_ops tmc_etf_cs_ops = {
>>
>> static int tmc_read_prepare(struct tmc_drvdata *drvdata)
>> {
>> - int ret;
>> + int ret = 0;
>> unsigned long flags;
>> enum tmc_mode mode;
>>
>> @@ -439,25 +439,31 @@ static int tmc_read_prepare(struct tmc_drvdata
>> *drvdata)
>> if (!drvdata->enable)
>> goto out;
>>
>> - if (drvdata->config_type == TMC_CONFIG_TYPE_ETB) {
>> + switch (drvdata->config_type) {
>> + case TMC_CONFIG_TYPE_ETB:
>> tmc_etb_disable_hw(drvdata);
>> - } else if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
>> - tmc_etr_disable_hw(drvdata);
>> - } else {
>> + break;
>> + case TMC_CONFIG_TYPE_ETF:
>> + /* There is no point in reading a TMC in HW FIFO mode */
>> mode = readl_relaxed(drvdata->base + TMC_MODE);
>> - if (mode == TMC_MODE_CIRCULAR_BUFFER) {
>> - tmc_etb_disable_hw(drvdata);
>> - } else {
>> - ret = -ENODEV;
>> + if (mode != TMC_MODE_CIRCULAR_BUFFER) {
>> + ret = -EINVAL;
>> goto err;
>> }
>
>
> Nit. If you move the TMC_CONFIG_TYPE_ETB here, you could fall through from
> TYPE_ETF: i.e,
Yes, that's what the end result look like [1]. I will refactor to
make the transition cleaner.
[1].
https://git.linaro.org/kernel/coresight.git/blob/refs/heads/next:/drivers/hwtracing/coresight/coresight-tmc.c#l76
> /* Fall through to ETB mode */
> case TMC_CONFIG_TYPE_ETB:
>>
>> +
>> + tmc_etb_disable_hw(drvdata);
>> + break;
>
>
>
>
>> + case TMC_CONFIG_TYPE_ETR:
>> + tmc_etr_disable_hw(drvdata);
>> + break;
>> + default:
>> + ret = -EINVAL;
>> + goto err;
>> }
>> +
>
>
>
>> return ret;
>> @@ -472,20 +478,30 @@ static void tmc_read_unprepare(struct tmc_drvdata
>> *drvdata)
>> if (!drvdata->enable)
>> goto out;
>>
>> - if (drvdata->config_type == TMC_CONFIG_TYPE_ETB) {
>> + switch (drvdata->config_type) {
>> + case TMC_CONFIG_TYPE_ETB:
>> tmc_etb_enable_hw(drvdata);
>> - } else if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
>> - tmc_etr_enable_hw(drvdata);
>> - } else {
>> + break;
>> + case TMC_CONFIG_TYPE_ETF:
>> + /* Make sure we don't re-enable a TMC in HW FIFO mode */
>> mode = readl_relaxed(drvdata->base + TMC_MODE);
>> - if (mode == TMC_MODE_CIRCULAR_BUFFER)
>> - tmc_etb_enable_hw(drvdata);
>> + if (mode != TMC_MODE_CIRCULAR_BUFFER)
>> + goto err;
>> +
>> + tmc_etb_enable_hw(drvdata);
>> + break;
>
>
> Same as above.
>
>> + case TMC_CONFIG_TYPE_ETR:
>> + tmc_etr_disable_hw(drvdata);
>> + break;
>> + default:
>> + goto err;
>> }
>> +
>
>
> Otherwise,
>
> Reviewed-by: Suzuki K Poulose <suzuki.poul...@arm.com>
>
>
