diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2021-10-19 17:31:46 +0100 |
|---|---|---|
| committer | Mathieu Poirier <mathieu.poirier@linaro.org> | 2021-10-27 11:45:52 -0600 |
| commit | e4bc8829a748c61ab07617b41da5d071b060126e (patch) | |
| tree | e662c24a60cb962d8ef8bd84eb049bfee7ef674a /drivers/hwtracing | |
| parent | 2336a7b29b5826a9cd15c39818ded665f88d2e5b (diff) | |
| download | linux-e4bc8829a748c61ab07617b41da5d071b060126e.tar.bz2 | |
coresight: trbe: Allow driver to choose a different alignment
The TRBE hardware mandates a minimum alignment for the TRBPTR_EL1,
advertised via the TRBIDR_EL1. This is used by the driver to
align the buffer write head. This patch allows the driver to
choose a different alignment from that of the hardware, by
decoupling the alignment tracking. This will be useful for
working around errata.
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-9-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Diffstat (limited to 'drivers/hwtracing')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-trbe.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c index ae0bde9630f6..cdbb134892f6 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.c +++ b/drivers/hwtracing/coresight/coresight-trbe.c @@ -67,8 +67,18 @@ struct trbe_buf { struct trbe_cpudata *cpudata; }; +/* + * struct trbe_cpudata: TRBE instance specific data + * @trbe_flag - TRBE dirty/access flag support + * @trbe_hw_align - Actual TRBE alignment required for TRBPTR_EL1. + * @trbe_align - Software alignment used for the TRBPTR_EL1. + * @cpu - CPU this TRBE belongs to. + * @mode - Mode of current operation. (perf/disabled) + * @drvdata - TRBE specific drvdata + */ struct trbe_cpudata { bool trbe_flag; + u64 trbe_hw_align; u64 trbe_align; int cpu; enum cs_mode mode; @@ -875,7 +885,7 @@ static ssize_t align_show(struct device *dev, struct device_attribute *attr, cha { struct trbe_cpudata *cpudata = dev_get_drvdata(dev); - return sprintf(buf, "%llx\n", cpudata->trbe_align); + return sprintf(buf, "%llx\n", cpudata->trbe_hw_align); } static DEVICE_ATTR_RO(align); @@ -967,11 +977,13 @@ static void arm_trbe_probe_cpu(void *info) goto cpu_clear; } - cpudata->trbe_align = 1ULL << get_trbe_address_align(trbidr); - if (cpudata->trbe_align > SZ_2K) { + cpudata->trbe_hw_align = 1ULL << get_trbe_address_align(trbidr); + if (cpudata->trbe_hw_align > SZ_2K) { pr_err("Unsupported alignment on cpu %d\n", cpu); goto cpu_clear; } + + cpudata->trbe_align = cpudata->trbe_hw_align; cpudata->trbe_flag = get_trbe_flag_update(trbidr); cpudata->cpu = cpu; cpudata->drvdata = drvdata; |