[Intel-gfx] [PATCH v3 04/16] drm/i915/perf: Determine gen12 oa ctx offset at runtime

Umesh Nerlige Ramappa umesh.nerlige.ramappa at intel.com
Tue Oct 11 18:19:17 UTC 2022


On Tue, Oct 11, 2022 at 08:47:00PM +0300, Jani Nikula wrote:
>On Mon, 10 Oct 2022, Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com> wrote:
>> Some SKUs of same gen12 platform may have different oactxctrl
>> offsets. For gen12, determine oactxctrl offsets at runtime.
>>
>> v2: (Lionel)
>> - Move MI definitions to intel_gpu_commands.h
>> - Ensure __find_reg_in_lri does read past context image size
>>
>> v3: (Ashutosh)
>> - Drop unnecessary use of double underscores
>> - fix find_reg_in_lri
>> - Return error if oa context offset is U32_MAX
>> - Error out if oa_ctx_ctrl_offset does not find offset
>>
>> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
>> ---
>>  drivers/gpu/drm/i915/gt/intel_gpu_commands.h |   4 +
>>  drivers/gpu/drm/i915/i915_perf.c             | 154 +++++++++++++++----
>>  drivers/gpu/drm/i915/i915_perf_oa_regs.h     |   2 +-
>>  3 files changed, 129 insertions(+), 31 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/gt/intel_gpu_commands.h b/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
>> index d4e9702d3c8e..f50ea92910d9 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
>> +++ b/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
>> @@ -187,6 +187,10 @@
>>  #define   MI_BATCH_RESOURCE_STREAMER REG_BIT(10)
>>  #define   MI_BATCH_PREDICATE         REG_BIT(15) /* HSW+ on RCS only*/
>>
>> +#define MI_OPCODE(x)		(((x) >> 23) & 0x3f)
>> +#define IS_MI_LRI_CMD(x)	(MI_OPCODE(x) == MI_OPCODE(MI_INSTR(0x22, 0)))
>> +#define MI_LRI_LEN(x)		(((x) & 0xff) + 1)
>> +
>>  /*
>>   * 3D instructions used by the kernel
>>   */
>> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
>> index cd57b5836386..b292aa39633e 100644
>> --- a/drivers/gpu/drm/i915/i915_perf.c
>> +++ b/drivers/gpu/drm/i915/i915_perf.c
>> @@ -1358,6 +1358,68 @@ static int gen12_get_render_context_id(struct i915_perf_stream *stream)
>>  	return 0;
>>  }
>>
>> +#define valid_oactxctrl_offset(x) ((x) && (x) != U32_MAX)
>> +static bool oa_find_reg_in_lri(u32 *state, u32 reg, u32 *offset, u32 end)
>> +{
>> +	u32 idx = *offset;
>> +	u32 len = min(MI_LRI_LEN(state[idx]) + idx, end);
>
>I don't understand any of this stuff, but why are the offset, index and
>length u32 instead of just, say, int?

I can use int, but the ce->engine->context_size is u32 and we are 
parsing the context image here, so I have just used the same type for 
offset, index, length.

Any guideline/recommendation to choose int over u32?

>
>> +	bool found = false;
>> +
>> +	idx++;
>> +	for (; idx < len; idx += 2) {
>
>I find the initialization of idx and len confusing, and thereby the
>entire loop too.

Considering that the context image is a collection of MI_LRI commands 
with each command having this format:

dword 0: MI_LRI
dword 1: reg offset
dword 2: reg value
dword 3: reg offset
dword 4: reg value
...

oa_context_image_offset() and oa_find_reg_in_lri() are parsing this 
context image to look for a specific reg_offset. Once the offset is 
known, the OA code programs the reg_value for the context.

Thanks,
Umesh

>
>BR,
>Jani.
>
>
>> +		if (state[idx] == reg) {
>> +			found = true;
>> +			break;
>> +		}
>> +	}
>> +
>> +	*offset = idx;
>> +	return found;
>> +}
>> +
>> +static u32 oa_context_image_offset(struct intel_context *ce, u32 reg)
>> +{
>> +	u32 offset, len = (ce->engine->context_size - PAGE_SIZE) / 4;
>> +	u32 *state = ce->lrc_reg_state;
>> +
>> +	for (offset = 0; offset < len; ) {
>> +		if (IS_MI_LRI_CMD(state[offset])) {
>> +			if (oa_find_reg_in_lri(state, reg, &offset, len))
>> +				break;
>> +		} else {
>> +			offset++;
>> +		}
>> +	}
>> +
>> +	return offset < len ? offset : U32_MAX;
>> +}
>> +
>> +static int set_oa_ctx_ctrl_offset(struct intel_context *ce)
>> +{
>> +	i915_reg_t reg = GEN12_OACTXCONTROL(ce->engine->mmio_base);
>> +	struct i915_perf *perf = &ce->engine->i915->perf;
>> +	u32 offset = perf->ctx_oactxctrl_offset;
>> +
>> +	/* Do this only once. Failure is stored as offset of U32_MAX */
>> +	if (offset)
>> +		goto exit;
>> +
>> +	offset = oa_context_image_offset(ce, i915_mmio_reg_offset(reg));
>> +	perf->ctx_oactxctrl_offset = offset;
>> +
>> +	drm_dbg(&ce->engine->i915->drm,
>> +		"%s oa ctx control at 0x%08x dword offset\n",
>> +		ce->engine->name, offset);
>> +
>> +exit:
>> +	return valid_oactxctrl_offset(offset) ? 0 : -ENODEV;
>> +}
>> +
>> +static bool engine_supports_mi_query(struct intel_engine_cs *engine)
>> +{
>> +	return engine->class == RENDER_CLASS;
>> +}
>> +
>>  /**
>>   * oa_get_render_ctx_id - determine and hold ctx hw id
>>   * @stream: An i915-perf stream opened for OA metrics
>> @@ -1377,6 +1439,21 @@ static int oa_get_render_ctx_id(struct i915_perf_stream *stream)
>>  	if (IS_ERR(ce))
>>  		return PTR_ERR(ce);
>>
>> +	if (engine_supports_mi_query(stream->engine)) {
>> +		/*
>> +		 * We are enabling perf query here. If we don't find the context
>> +		 * offset here, just return an error.
>> +		 */
>> +		ret = set_oa_ctx_ctrl_offset(ce);
>> +		if (ret) {
>> +			intel_context_unpin(ce);
>> +			drm_err(&stream->perf->i915->drm,
>> +				"Enabling perf query failed for %s\n",
>> +				stream->engine->name);
>> +			return ret;
>> +		}
>> +	}
>> +
>>  	switch (GRAPHICS_VER(ce->engine->i915)) {
>>  	case 7: {
>>  		/*
>> @@ -2408,10 +2485,11 @@ static int gen12_configure_oar_context(struct i915_perf_stream *stream,
>>  	int err;
>>  	struct intel_context *ce = stream->pinned_ctx;
>>  	u32 format = stream->oa_buffer.format;
>> +	u32 offset = stream->perf->ctx_oactxctrl_offset;
>>  	struct flex regs_context[] = {
>>  		{
>>  			GEN8_OACTXCONTROL,
>> -			stream->perf->ctx_oactxctrl_offset + 1,
>> +			offset + 1,
>>  			active ? GEN8_OA_COUNTER_RESUME : 0,
>>  		},
>>  	};
>> @@ -2436,15 +2514,18 @@ static int gen12_configure_oar_context(struct i915_perf_stream *stream,
>>  		},
>>  	};
>>
>> -	/* Modify the context image of pinned context with regs_context*/
>> -	err = intel_context_lock_pinned(ce);
>> -	if (err)
>> -		return err;
>> +	/* Modify the context image of pinned context with regs_context */
>> +	if (valid_oactxctrl_offset(offset)) {
>> +		err = intel_context_lock_pinned(ce);
>> +		if (err)
>> +			return err;
>>
>> -	err = gen8_modify_context(ce, regs_context, ARRAY_SIZE(regs_context));
>> -	intel_context_unlock_pinned(ce);
>> -	if (err)
>> -		return err;
>> +		err = gen8_modify_context(ce, regs_context,
>> +					  ARRAY_SIZE(regs_context));
>> +		intel_context_unlock_pinned(ce);
>> +		if (err)
>> +			return err;
>> +	}
>>
>>  	/* Apply regs_lri using LRI with pinned context */
>>  	return gen8_modify_self(ce, regs_lri, ARRAY_SIZE(regs_lri), active);
>> @@ -2566,6 +2647,7 @@ lrc_configure_all_contexts(struct i915_perf_stream *stream,
>>  			   const struct i915_oa_config *oa_config,
>>  			   struct i915_active *active)
>>  {
>> +	u32 ctx_oactxctrl = stream->perf->ctx_oactxctrl_offset;
>>  	/* The MMIO offsets for Flex EU registers aren't contiguous */
>>  	const u32 ctx_flexeu0 = stream->perf->ctx_flexeu0_offset;
>>  #define ctx_flexeuN(N) (ctx_flexeu0 + 2 * (N) + 1)
>> @@ -2576,7 +2658,7 @@ lrc_configure_all_contexts(struct i915_perf_stream *stream,
>>  		},
>>  		{
>>  			GEN8_OACTXCONTROL,
>> -			stream->perf->ctx_oactxctrl_offset + 1,
>> +			ctx_oactxctrl + 1,
>>  		},
>>  		{ EU_PERF_CNTL0, ctx_flexeuN(0) },
>>  		{ EU_PERF_CNTL1, ctx_flexeuN(1) },
>> @@ -4545,6 +4627,37 @@ static void oa_init_supported_formats(struct i915_perf *perf)
>>  	}
>>  }
>>
>> +static void i915_perf_init_info(struct drm_i915_private *i915)
>> +{
>> +	struct i915_perf *perf = &i915->perf;
>> +
>> +	switch (GRAPHICS_VER(i915)) {
>> +	case 8:
>> +		perf->ctx_oactxctrl_offset = 0x120;
>> +		perf->ctx_flexeu0_offset = 0x2ce;
>> +		perf->gen8_valid_ctx_bit = BIT(25);
>> +		break;
>> +	case 9:
>> +		perf->ctx_oactxctrl_offset = 0x128;
>> +		perf->ctx_flexeu0_offset = 0x3de;
>> +		perf->gen8_valid_ctx_bit = BIT(16);
>> +		break;
>> +	case 11:
>> +		perf->ctx_oactxctrl_offset = 0x124;
>> +		perf->ctx_flexeu0_offset = 0x78e;
>> +		perf->gen8_valid_ctx_bit = BIT(16);
>> +		break;
>> +	case 12:
>> +		/*
>> +		 * Calculate offset at runtime in oa_pin_context for gen12 and
>> +		 * cache the value in perf->ctx_oactxctrl_offset.
>> +		 */
>> +		break;
>> +	default:
>> +		MISSING_CASE(GRAPHICS_VER(i915));
>> +	}
>> +}
>> +
>>  /**
>>   * i915_perf_init - initialize i915-perf state on module bind
>>   * @i915: i915 device instance
>> @@ -4583,6 +4696,7 @@ void i915_perf_init(struct drm_i915_private *i915)
>>  		 * execlist mode by default.
>>  		 */
>>  		perf->ops.read = gen8_oa_read;
>> +		i915_perf_init_info(i915);
>>
>>  		if (IS_GRAPHICS_VER(i915, 8, 9)) {
>>  			perf->ops.is_valid_b_counter_reg =
>> @@ -4602,18 +4716,6 @@ void i915_perf_init(struct drm_i915_private *i915)
>>  			perf->ops.enable_metric_set = gen8_enable_metric_set;
>>  			perf->ops.disable_metric_set = gen8_disable_metric_set;
>>  			perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>> -
>> -			if (GRAPHICS_VER(i915) == 8) {
>> -				perf->ctx_oactxctrl_offset = 0x120;
>> -				perf->ctx_flexeu0_offset = 0x2ce;
>> -
>> -				perf->gen8_valid_ctx_bit = BIT(25);
>> -			} else {
>> -				perf->ctx_oactxctrl_offset = 0x128;
>> -				perf->ctx_flexeu0_offset = 0x3de;
>> -
>> -				perf->gen8_valid_ctx_bit = BIT(16);
>> -			}
>>  		} else if (GRAPHICS_VER(i915) == 11) {
>>  			perf->ops.is_valid_b_counter_reg =
>>  				gen7_is_valid_b_counter_addr;
>> @@ -4627,11 +4729,6 @@ void i915_perf_init(struct drm_i915_private *i915)
>>  			perf->ops.enable_metric_set = gen8_enable_metric_set;
>>  			perf->ops.disable_metric_set = gen11_disable_metric_set;
>>  			perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>> -
>> -			perf->ctx_oactxctrl_offset = 0x124;
>> -			perf->ctx_flexeu0_offset = 0x78e;
>> -
>> -			perf->gen8_valid_ctx_bit = BIT(16);
>>  		} else if (GRAPHICS_VER(i915) == 12) {
>>  			perf->ops.is_valid_b_counter_reg =
>>  				gen12_is_valid_b_counter_addr;
>> @@ -4645,9 +4742,6 @@ void i915_perf_init(struct drm_i915_private *i915)
>>  			perf->ops.enable_metric_set = gen12_enable_metric_set;
>>  			perf->ops.disable_metric_set = gen12_disable_metric_set;
>>  			perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
>> -
>> -			perf->ctx_flexeu0_offset = 0;
>> -			perf->ctx_oactxctrl_offset = 0x144;
>>  		}
>>  	}
>>
>> diff --git a/drivers/gpu/drm/i915/i915_perf_oa_regs.h b/drivers/gpu/drm/i915/i915_perf_oa_regs.h
>> index f31c9f13a9fc..0ef3562ff4aa 100644
>> --- a/drivers/gpu/drm/i915/i915_perf_oa_regs.h
>> +++ b/drivers/gpu/drm/i915/i915_perf_oa_regs.h
>> @@ -97,7 +97,7 @@
>>  #define  GEN12_OAR_OACONTROL_COUNTER_FORMAT_SHIFT 1
>>  #define  GEN12_OAR_OACONTROL_COUNTER_ENABLE       (1 << 0)
>>
>> -#define GEN12_OACTXCONTROL _MMIO(0x2360)
>> +#define GEN12_OACTXCONTROL(base) _MMIO((base) + 0x360)
>>  #define GEN12_OAR_OASTATUS _MMIO(0x2968)
>>
>>  /* Gen12 OAG unit */
>
>-- 
>Jani Nikula, Intel Open Source Graphics Center


More information about the Intel-gfx mailing list