STRUCT TMC_DRVDATA(9)

🎀 struct tmc_drvdata 🎀

Okay bestie, welcome to the Kernel API Manual page for struct tmc_drvdata(9). This is the struct that holds the specifics associated to an TMC component — literally the little data homebase for a TMC component. 💅

💖 NAME 💖

struct tmc_drvdata — specifics associated to an TMC component. ✨

🦋 SYNOPSIS 🦋

       struct tmc_drvdata {
           struct clk              *atclk;
           struct clk              *pclk;
           void __iomem            *base;
           struct coresight_device *csdev;
           struct miscdevice       miscdev;
           struct miscdevice       crashdev;
           raw_spinlock_t spinlock;
           pid_t pid;
           bool reading;
           bool stop_on_flush;
           union {
             char *buf;
             struct etr_buf  *etr_buf;
           };
           u32 len;
           u32 size;
           u32 max_burst_size;
           enum tmc_config_type    config_type;
           enum tmc_mem_intf_width memwidth;
           u32 trigger_cntr;
           u32 etr_caps;
           enum etr_mode           etr_mode;
           struct idr              idr;
           struct mutex            idr_mutex;
           struct etr_buf          *sysfs_buf;
           struct etr_buf          *perf_buf;
           struct tmc_resrv_buf    resrv_buf;
           struct tmc_resrv_buf    crash_mdata;
        };

🫶 Members 🫶

• atclk — optional clock for the core parts of the TMC. 🕰️
• pclk — APB clock if present, otherwise NULL. 🫧
• base — memory mapped base address for this component. 📍
• csdev — component vitals needed by the framework. 🫀
• miscdev — specifics to handle the /dev/xyz.tmc entry. 🎟️
• crashdev — specifics to handle the /dev/crash_tmc_xyz entry for reading crash tracedata. 💥
• spinlock — only one at a time pls. 🙅‍♀️
• pid — process ID of the process that owns the session that is using this component. For example, this would be the pid of the Perf process. 🧠
• reading — says the buffer's in the reading-through-/dev/xyz.tmc entry state. 👀
• stop_on_flush — stop on flush trigger user configuration. 🛑
• {unnamed_union} — anonymous. 🫥
  • buf — snapshot of the trace data for ETF/ETB. 📸
  • etr_buf — details of the buffer used in TMC-ETR. 🧾
• len — size of the available trace for ETF/ETB. 📏
• size — trace buffer size for this TMC (common for all modes). 📦
• max_burst_size — the maximum burst size that can be initiated by TMC-ETR on the AXI bus. 🚀
• config_type — TMC variant, must be of type tmc_config_type. 🏷️
• memwidth — width of the memory interface databus, in bytes. 📐
• trigger_cntr — amount of words to store after a trigger. 🎯
• etr_caps — bitmask of capabilities of the TMC ETR, inferred from the device configuration register (DEVID). 🧬
• etr_mode — user preferred mode of the ETR device, default auto mode. 🎛️
• idr — holds etr_bufs allocated for this ETR. 🗂️
• idr_mutex — access serialisation for idr. 🔐
• sysfs_buf — SYSFS buffer for ETR. 🗃️
• perf_buf — PERF buffer for ETR. 📊
• resrv_buf — used by ETR as hardware trace buffer and for trace data retention (after crash) only when ETR_MODE_RESRV buffer mode is enabled. Used by ETF for trace data retention (after crash) by default. 🛟
• crash_mdata — reserved memory for storing tmc crash metadata. Used by ETR/ETF. 🧷

🔎 SEE ALSO 🔎

Kernel file ./drivers/hwtracing/coresight/coresight-tmc.h, plus struct etr_buf(9) and struct tmc_pages(9). Go read those too, bestie. 📚

Mwah 💋 this page comes from the Kernel API Manual, source ./drivers/hwtracing/coresight, dated October 2026, and it's all about struct tmc_drvdata(9). periodt. 🫶