Re: [PATCH 2/6] coresight: Fix holes in struct etmv4_config

Hi James

On Mon, 11 Aug 2025 at 10:32, James Clark james.clark@linaro.org wrote:

Lots of u8s are mixed with u64s and u32s so repack it to save a bit of space because there's one of these for each ETM.

Signed-off-by: James Clark james.clark@linaro.org

drivers/hwtracing/coresight/coresight-etm4x.h | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 746627476bd3..a355a1e9606d 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -832,28 +832,33 @@ struct etmv4_config { u32 vipcssctlr; u8 seq_idx; u8 syncfreq;

•   u8                              cntr_idx;
  

•   u8                              res_idx;
  

•   u8                              ss_idx;
  

•   u8                              addr_idx;
  

•   u8                              addr_type[ETM_MAX_SINGLE_ADDR_CMP];
  

•   u8                              ctxid_idx;
  

•   u8                              vmid_idx;
    u32                             seq_ctrl[ETM_MAX_SEQ_STATES];
    u32                             seq_rst;
    u32                             seq_state;
  

•   u8                              cntr_idx;
  

•   u32                             cntrldvr[ETMv4_MAX_CNTR];
    u32                             cntr_ctrl[ETMv4_MAX_CNTR];
    u32                             cntr_val[ETMv4_MAX_CNTR];
  

•   u8                              res_idx;
  

•   u32                             res_ctrl[ETM_MAX_RES_SEL];
  

•   u8                              ss_idx;
  

•   u32                             ss_ctrl[ETM_MAX_SS_CMP];
    u32                             ss_status[ETM_MAX_SS_CMP];
    u32                             ss_pe_cmp[ETM_MAX_SS_CMP];
  

•   u8                              addr_idx;
  

•   u64                             addr_val[ETM_MAX_SINGLE_ADDR_CMP];
    u64                             addr_acc[ETM_MAX_SINGLE_ADDR_CMP];
  

•   u8                              addr_type[ETM_MAX_SINGLE_ADDR_CMP];
  

this is 16 x u8 - could this not just stay here?

•   u8                              ctxid_idx;
  

•   u64                             ctxid_pid[ETMv4_MAX_CTXID_CMP];
    u32                             ctxid_mask0;
    u32                             ctxid_mask1;
  

•   u8                              vmid_idx;
    u64                             vmid_val[ETM_MAX_VMID_CMP];
    u32                             vmid_mask0;
    u32                             vmid_mask1;
  
  

-- 2.34.1

These attributes have been functionally grouped for ease of understanding. If we move the _idx values away from what they are indexing, we probably need comments cross referencing from where they where and where they have gone to.

Mike