[PATCH 04/19] coresight: trbe: Remove set_trbe_disabled() from the enable flow
Anshuman Khandual
anshuman.khandual at arm.com
Thu Dec 4 04:43:56 PST 2025
On 01/12/25 4:51 PM, Leo Yan wrote:
> set_trbe_disabled() should never appear in the enable flow, otherwise,
> it may potentially hide bugs in the disable flow.
>
> Remove set_trbe_disabled() from the enable path.
IIRC without first disabling TRBLIMITR_EL1_E - TRBE registers or their
fields should not be fetched or interpreted. Without that none of the
subsequent HW operations should be performed inside trbe_enable_hw()
leading upto enabling it.
>
> Signed-off-by: Leo Yan <leo.yan at arm.com>
> ---
> drivers/hwtracing/coresight/coresight-trbe.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
> index f5597bd9b5fba9a8f5053d5823b03380fd468b5c..e426991e2c2c398a9d3982e9d0f7f542e404cbab 100644
> --- a/drivers/hwtracing/coresight/coresight-trbe.c
> +++ b/drivers/hwtracing/coresight/coresight-trbe.c
> @@ -629,7 +629,6 @@ static void trbe_enable_hw(struct trbe_buf *buf)
> WARN_ON(buf->trbe_hw_base < buf->trbe_base);
> WARN_ON(buf->trbe_write < buf->trbe_hw_base);
> WARN_ON(buf->trbe_write >= buf->trbe_limit);
> - set_trbe_disabled(buf->cpudata);
> clr_trbe_status();
> set_trbe_base_pointer(buf->trbe_hw_base);
> set_trbe_write_pointer(buf->trbe_write);
>
More information about the linux-arm-kernel
mailing list