Re: [PATCH] drm/xe/debugfs: Expose per-engine idle status

["Anirban, Sk" <sk.anirban@intel.com>]

Hi,

On 29-08-2026 05:00 am, Belgaumkar, Vinay wrote:
>
> On 7/23/2026 12:43 PM, Sk Anirban wrote:
>> Extend the existing "hw_engines" debugfs to iterate over all hardware
>> engines and dump their idle state: whether the engine pipe is idle or
>> busy, whether C6 entry is allowed, and (where available) the forcewake
>> request status.
>>
>> v2: Use existing debugfs (Matt Brost)
>>
>> Signed-off-by: Sk Anirban <sk.anirban@intel.com>
>> ---
>>   drivers/gpu/drm/xe/regs/xe_gt_regs.h | 27 ++++++++++++++
>>   drivers/gpu/drm/xe/xe_devcoredump.c  |  4 ++-
>>   drivers/gpu/drm/xe/xe_gt_debugfs.c   | 54 +++++++++++++++++++++++++++-
>>   drivers/gpu/drm/xe/xe_guc_capture.c  |  2 --
>>   4 files changed, 83 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/regs/xe_gt_regs.h 
>> b/drivers/gpu/drm/xe/regs/xe_gt_regs.h
>> index 08251c7a1a4b..accf3012bad2 100644
>> --- a/drivers/gpu/drm/xe/regs/xe_gt_regs.h
>> +++ b/drivers/gpu/drm/xe/regs/xe_gt_regs.h
>> @@ -196,6 +196,33 @@
>>   #define   MSC_MSAA_REODER_BUF_BYPASS_DISABLE    REG_BIT(14)
>>   #define   FAST_CLEAR_VALIGN_FIX            REG_BIT(13)
>>   +#define MSG_IDLE_CS                XE_REG(0x8000)
>> +#define MSG_IDLE_VCS0                XE_REG(0x8004)
>> +#define MSG_IDLE_VCS1                XE_REG(0x8008)
>> +#define MSG_IDLE_VCS2                XE_REG(0x80C0)
>> +#define MSG_IDLE_VCS3                XE_REG(0x80C4)
>> +#define MSG_IDLE_VCS4                XE_REG(0x80C8)
>> +#define MSG_IDLE_VCS5                XE_REG(0x80CC)
>> +#define MSG_IDLE_VCS6                XE_REG(0x80D0)
>> +#define MSG_IDLE_VCS7                XE_REG(0x80D4)
>> +#define MSG_IDLE_VECS0                XE_REG(0x8010)
>> +#define MSG_IDLE_VECS1                XE_REG(0x80D8)
>> +#define MSG_IDLE_VECS2                XE_REG(0x80DC)
>> +#define MSG_IDLE_VECS3                XE_REG(0x80E0)
>> +#define MSG_IDLE_BCS0                XE_REG(0x800C)
>> +#define MSG_IDLE_BCS1                XE_REG(0x8680)
>> +#define MSG_IDLE_BCS2                XE_REG(0x8684)
>> +#define MSG_IDLE_BCS3                XE_REG(0x8688)
>> +#define MSG_IDLE_BCS4                XE_REG(0x868C)
>> +#define MSG_IDLE_BCS5                XE_REG(0x8690)
>> +#define MSG_IDLE_BCS6                XE_REG(0x8694)
>> +#define MSG_IDLE_BCS7                XE_REG(0x8698)
>> +#define MSG_IDLE_BCS8                XE_REG(0x869C)
>> +#define MSG_IDLE_GSCCS0                XE_REG(0xA62C)
>> +#define   MSG_IDLE_INDICATION            REG_BIT(0)
>> +#define   MSG_IDLE_C6_ALLOWED            REG_BIT(1)
>> +#define   MSG_IDLE_FW_STATUS            REG_GENMASK(13, 9)
> This field is called FW_REQ in bspec, we should stick to the same, so 
> MSG_IDLE_FW_REQ.
Sure, I will modify this.
>> +
>>   #define XE2LPM_CCCHKNREG1            XE_REG(0x82a8)
>>     #define VF_PREEMPTION                XE_REG(0x83a4, 
>> XE_REG_OPTION_MASKED)
>> diff --git a/drivers/gpu/drm/xe/xe_devcoredump.c 
>> b/drivers/gpu/drm/xe/xe_devcoredump.c
>> index 5f2b90b18f97..b918f046ae15 100644
>> --- a/drivers/gpu/drm/xe/xe_devcoredump.c
>> +++ b/drivers/gpu/drm/xe/xe_devcoredump.c
>> @@ -127,8 +127,10 @@ static ssize_t __xe_devcoredump_read(char 
>> *buffer, ssize_t count,
>>         drm_puts(&p, "\n**** HW Engines ****\n");
>>       for (i = 0; i < XE_NUM_HW_ENGINES; i++)
>> -        if (ss->hwe[i])
>> +        if (ss->hwe[i]) {
>>               xe_engine_snapshot_print(ss->hwe[i], &p);
>> +            drm_puts(&p, "\n");
>> +        }
>>         drm_puts(&p, "\n**** VM state ****\n");
>>       xe_vm_snapshot_print(ss->vm, &p);
>> diff --git a/drivers/gpu/drm/xe/xe_gt_debugfs.c 
>> b/drivers/gpu/drm/xe/xe_gt_debugfs.c
>> index c38bcacb27e4..621d1e57e997 100644
>> --- a/drivers/gpu/drm/xe/xe_gt_debugfs.c
>> +++ b/drivers/gpu/drm/xe/xe_gt_debugfs.c
>> @@ -10,6 +10,7 @@
>>   #include <drm/drm_debugfs.h>
>>   #include <drm/drm_managed.h>
>>   +#include "regs/xe_gt_regs.h"
>>   #include "xe_device.h"
>>   #include "xe_force_wake.h"
>>   #include "xe_gt.h"
>> @@ -22,6 +23,7 @@
>>   #include "xe_guc_hwconfig.h"
>>   #include "xe_hw_engine.h"
>>   #include "xe_lrc.h"
>> +#include "xe_mmio.h"
>>   #include "xe_mocs.h"
>>   #include "xe_pat.h"
>>   #include "xe_pm.h"
>> @@ -111,6 +113,38 @@ int xe_gt_debugfs_show_with_rpm(struct seq_file 
>> *m, void *data)
>>     static int hw_engines(struct xe_gt *gt, struct drm_printer *p)
>>   {
>> +    static const struct {
>> +        struct xe_reg reg;
>> +        bool has_fw;
>> +    } msg_idle_reg[XE_NUM_HW_ENGINES] = {
>> +        [XE_HW_ENGINE_RCS0] = { MSG_IDLE_CS, true },
>> +        [XE_HW_ENGINE_BCS0] = { MSG_IDLE_BCS0, true },
>> +        [XE_HW_ENGINE_BCS1] = { MSG_IDLE_BCS1, false },
>> +        [XE_HW_ENGINE_BCS2] = { MSG_IDLE_BCS2, false },
>> +        [XE_HW_ENGINE_BCS3] = { MSG_IDLE_BCS3, false },
>> +        [XE_HW_ENGINE_BCS4] = { MSG_IDLE_BCS4, false },
>> +        [XE_HW_ENGINE_BCS5] = { MSG_IDLE_BCS5, false },
>> +        [XE_HW_ENGINE_BCS6] = { MSG_IDLE_BCS6, false },
>> +        [XE_HW_ENGINE_BCS7] = { MSG_IDLE_BCS7, false },
>> +        [XE_HW_ENGINE_BCS8] = { MSG_IDLE_BCS8, false },
>> +        [XE_HW_ENGINE_VCS0] = { MSG_IDLE_VCS0, true },
>> +        [XE_HW_ENGINE_VCS1] = { MSG_IDLE_VCS1, true },
>> +        [XE_HW_ENGINE_VCS2] = { MSG_IDLE_VCS2, true },
>> +        [XE_HW_ENGINE_VCS3] = { MSG_IDLE_VCS3, true },
>> +        [XE_HW_ENGINE_VCS4] = { MSG_IDLE_VCS4, true },
>> +        [XE_HW_ENGINE_VCS5] = { MSG_IDLE_VCS5, true },
>> +        [XE_HW_ENGINE_VCS6] = { MSG_IDLE_VCS6, true },
>> +        [XE_HW_ENGINE_VCS7] = { MSG_IDLE_VCS7, true },
>> +        [XE_HW_ENGINE_VECS0] = { MSG_IDLE_VECS0, true },
>> +        [XE_HW_ENGINE_VECS1] = { MSG_IDLE_VECS1, true },
>> +        [XE_HW_ENGINE_VECS2] = { MSG_IDLE_VECS2, true },
>> +        [XE_HW_ENGINE_VECS3] = { MSG_IDLE_VECS3, true },
>> +        [XE_HW_ENGINE_CCS0] = { MSG_IDLE_CS, true },
>> +        [XE_HW_ENGINE_CCS1] = { MSG_IDLE_CS, true },
>> +        [XE_HW_ENGINE_CCS2] = { MSG_IDLE_CS, true },
>> +        [XE_HW_ENGINE_CCS3] = { MSG_IDLE_CS, true },
>> +        [XE_HW_ENGINE_GSCCS0] = { MSG_IDLE_GSCCS0, false },
> aren't the media related idle message registers only valid for media 
> GT and similarly those for render on render GT? Here we seem to be 
> reading all registers on both GTs? So some values are invalid.
for_each_hw_engine() only iterates engines present on that GT. So on 
each GT we only read its own engines' idle registers.
>> +    };
>>       struct xe_hw_engine *hwe;
>>       enum xe_hw_engine_id id;
>>   @@ -118,9 +152,27 @@ static int hw_engines(struct xe_gt *gt, struct 
>> drm_printer *p)
>>       if (!xe_force_wake_ref_has_domain(fw_ref.domains, 
>> XE_FORCEWAKE_ALL))
>>           return -ETIMEDOUT;
>>   -    for_each_hw_engine(hwe, gt, id)
>> +    for_each_hw_engine(hwe, gt, id) {
>> +        struct xe_reg reg = msg_idle_reg[id].reg;
>> +        u32 val;
>> +
>>           xe_hw_engine_print(hwe, p);
>>   +        val = xe_mmio_read32(&gt->mmio, reg);
>> +
>> +        if (msg_idle_reg[id].has_fw)
>> +            drm_printf(p, "\tpipe %s, C6 %s, fw_req 0x%02x\n",
>> +                   val & MSG_IDLE_INDICATION ? "idle" : "busy",
>> +                   val & MSG_IDLE_C6_ALLOWED ? "allowed" : "not 
>> allowed",
>> +                   REG_FIELD_GET(MSG_IDLE_FW_STATUS, val));
>
> should be FW_REQ here as well.
Sure, I will modify this.

Thanks,
Anirban

>
> Thanks,
>
> Vinay.
>
>> +        else
>> +            drm_printf(p, "\tpipe %s, C6 %s\n",
>> +                   val & MSG_IDLE_INDICATION ? "idle" : "busy",
>> +                   val & MSG_IDLE_C6_ALLOWED ? "allowed" : "not 
>> allowed");
>> +
>> +        drm_puts(p, "\n");
>> +    }
>> +
>>       return 0;
>>   }
>>   diff --git a/drivers/gpu/drm/xe/xe_guc_capture.c 
>> b/drivers/gpu/drm/xe/xe_guc_capture.c
>> index 82df19b304e1..5a4d085660a2 100644
>> --- a/drivers/gpu/drm/xe/xe_guc_capture.c
>> +++ b/drivers/gpu/drm/xe/xe_guc_capture.c
>> @@ -1868,8 +1868,6 @@ void xe_engine_snapshot_print(struct 
>> xe_hw_engine_snapshot *snapshot, struct drm
>>           snapshot_print_by_list_order(snapshot, p, 
>> GUC_STATE_CAPTURE_TYPE_ENGINE_CLASS,
>>                            list);
>>       }
>> -
>> -    drm_puts(p, "\n");
>>   }
>>     /**