1. 05 Aug, 2015 1 commit
    • Ankit Gupta's avatar
      spmi: add command tracepoints for SPMI · a9fce374
      Ankit Gupta authored
      Add tracepoints to retrieve information about read, write
      and non-data commands. For performance measurement support
      tracepoints are added at the beginning and at the end of
      transfers. Following is a list showing the new tracepoint
      events. The "cmd" parameter here represents the opcode, SID,
      and full 16-bit address.
      
      spmi_write_begin: cmd and data buffer.
      spmi_write_end  : cmd and return value.
      spmi_read_begin : cmd.
      spmi_read_end   : cmd, return value and data buffer.
      spmi_cmd        : cmd.
      
      The reason that cmd appears at both the beginning and at
      the end event is that SPMI drivers can request commands
      concurrently. cmd helps in matching the corresponding
      events.
      
      SPMI tracepoints can be enabled like:
      
      echo 1 >/sys/kernel/debug/tracing/events/spmi/enable
      
      and will dump messages that can be viewed in
      /sys/kernel/debug/tracing/trace that look like:
      
      ... spmi_read_begin: opc=56 sid=00 addr=0x0000
      ... spmi_read_end: opc=56 sid=00 addr=0x0000 ret=0 len=02 buf=0x[01-40]
      ... spmi_write_begin: opc=48 sid=00 addr=0x0000 len=3 buf=0x[ff-ff-ff]
      Suggested-by: default avatarSagar Dharia <sdharia@codeaurora.org>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Reviewed-by: default avatarStephen Boyd <sboyd@codeaurora.org>
      Signed-off-by: default avatarGilad Avidov <gavidov@codeaurora.org>
      Signed-off-by: default avatarAnkit Gupta <ankgupta@codeaurora.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a9fce374