On 15 June 2017 at 04:13, Suzuki K Poulose [off-list ref] wrote:

On 14/06/17 18:49, Mathieu Poirier wrote:

quoted

On Mon, Jun 12, 2017 at 03:36:44PM +0100, Suzuki K Poulose wrote:

quoted

Coresight TMC splits 64bit registers into a pair of 32bit registers
(e.g DBA, RRP, RWP). Provide helpers to read/write to these registers.

I'm good with this patch but please specify these changes are to support
the
SoC-600 suite.  That way when we look back at this set in a couple of
years we
don't loose hair thinking we've been carrying bugs all this time.

To be honest, these are not necessarily just for the support of SoC-600.
It is applies to the current driver with SoC-400, as you could see below,
where we have always assumed that the RRP/RWP/DBA HI bits are always
0. Technically, the TMC supports upto 40bits and hence we have been doing
it wrong.

I just had another look at the documentation and you are correct -
disregard my comment for this patch.

quoted

quoted

-       read_ptr = readl_relaxed(drvdata->base + TMC_RRP);
-       write_ptr = readl_relaxed(drvdata->base + TMC_RWP);
+       read_ptr = tmc_read_rrp(drvdata);
+       write_ptr = tmc_read_rwp(drvdata);

quoted

quoted

-               writel_relaxed(read_ptr, drvdata->base + TMC_RRP);
+               tmc_write_rrp(drvdata, read_ptr);
                perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);

quoted

quoted

        writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
+       tmc_write_dba(drvdata, drvdata->paddr);

-       writel_relaxed(drvdata->paddr, drvdata->base + TMC_DBALO);
-       writel_relaxed(0x0, drvdata->base + TMC_DBAHI);

quoted

quoted

-       rwp = readl_relaxed(drvdata->base + TMC_RWP);
+       rwp = tmc_read_rwp(drvdata);
        val = readl_relaxed(drvdata->base + TMC_STS);

Suzuki