> -----Original Message-----
> From: Dixit, Ashutosh <ashutosh.dixit@xxxxxxxxx>
> Sent: Thursday, April 7, 2022 12:49 AM
> To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: Gupta, Anshuman <anshuman.gupta@xxxxxxxxx>
> Subject: [PATCH] drm/i915/rps: Centralize computation of freq caps
>
> Freq caps (i.e. RP0, RP1 and RPn frequencies) are read from HW. However the
> formats (bit positions, widths, registers and units) of these vary for different
> generations with even more variations arriving in the future. In order not to
> have to do identical computation for these caps in multiple places, here we
> centralize the computation of these caps. This makes the code cleaner and also
> more extensible for the future.
>
> v2: Clarify that caps are in "hw units" in comments (Lucas De Marchi)
> v3: Minor checkpatch fix
> v4: s/intel_rps_get_freq_caps/gen6_rps_get_freq_caps/ (Badal Nilawar)
> v5: Changes comments to kernel doc (Anshuman Gupta)
Acked-by: Anshuman Gupta <anshuman.gupta@xxxxxxxxx>
>
> Cc: Anshuman Gupta <anshuman.gupta@xxxxxxxxx>
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
> Reviewed-by: Badal Nilawar <badal.nilawar@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c | 24 +---
> drivers/gpu/drm/i915/gt/intel_rps.c | 108 +++++++++++-------
> drivers/gpu/drm/i915/gt/intel_rps.h | 2 +-
> drivers/gpu/drm/i915/gt/intel_rps_types.h | 15 +++
> drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c | 14 +--
> 5 files changed, 91 insertions(+), 72 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> b/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> index 003a53c49c86..0c6b9eb724ae 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> @@ -342,17 +342,16 @@ void intel_gt_pm_frequency_dump(struct intel_gt
> *gt, struct drm_printer *p)
> } else if (GRAPHICS_VER(i915) >= 6) {
> u32 rp_state_limits;
> u32 gt_perf_status;
> - u32 rp_state_cap;
> + struct intel_rps_freq_caps caps;
> u32 rpmodectl, rpinclimit, rpdeclimit;
> u32 rpstat, cagf, reqf;
> u32 rpcurupei, rpcurup, rpprevup;
> u32 rpcurdownei, rpcurdown, rpprevdown;
> u32 rpupei, rpupt, rpdownei, rpdownt;
> u32 pm_ier, pm_imr, pm_isr, pm_iir, pm_mask;
> - int max_freq;
>
> rp_state_limits = intel_uncore_read(uncore,
> GEN6_RP_STATE_LIMITS);
> - rp_state_cap = intel_rps_read_state_cap(rps);
> + gen6_rps_get_freq_caps(rps, &caps);
> if (IS_GEN9_LP(i915))
> gt_perf_status = intel_uncore_read(uncore,
> BXT_GT_PERF_STATUS);
> else
> @@ -474,25 +473,12 @@ void intel_gt_pm_frequency_dump(struct intel_gt
> *gt, struct drm_printer *p)
> drm_printf(p, "RP DOWN THRESHOLD: %d (%lldns)\n",
> rpdownt, intel_gt_pm_interval_to_ns(gt, rpdownt));
>
> - max_freq = (IS_GEN9_LP(i915) ? rp_state_cap >> 0 :
> - rp_state_cap >> 16) & 0xff;
> - max_freq *= (IS_GEN9_BC(i915) ||
> - GRAPHICS_VER(i915) >= 11 ? GEN9_FREQ_SCALER :
> 1);
> drm_printf(p, "Lowest (RPN) frequency: %dMHz\n",
> - intel_gpu_freq(rps, max_freq));
> -
> - max_freq = (rp_state_cap & 0xff00) >> 8;
> - max_freq *= (IS_GEN9_BC(i915) ||
> - GRAPHICS_VER(i915) >= 11 ? GEN9_FREQ_SCALER :
> 1);
> + intel_gpu_freq(rps, caps.min_freq));
> drm_printf(p, "Nominal (RP1) frequency: %dMHz\n",
> - intel_gpu_freq(rps, max_freq));
> -
> - max_freq = (IS_GEN9_LP(i915) ? rp_state_cap >> 16 :
> - rp_state_cap >> 0) & 0xff;
> - max_freq *= (IS_GEN9_BC(i915) ||
> - GRAPHICS_VER(i915) >= 11 ? GEN9_FREQ_SCALER :
> 1);
> + intel_gpu_freq(rps, caps.rp1_freq));
> drm_printf(p, "Max non-overclocked (RP0) frequency:
> %dMHz\n",
> - intel_gpu_freq(rps, max_freq));
> + intel_gpu_freq(rps, caps.rp0_freq));
> drm_printf(p, "Max overclocked frequency: %dMHz\n",
> intel_gpu_freq(rps, rps->max_freq));
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c
> b/drivers/gpu/drm/i915/gt/intel_rps.c
> index 6c9fdf7906c5..3476a11f294c 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
> @@ -1070,24 +1070,67 @@ int intel_rps_set(struct intel_rps *rps, u8 val)
> return 0;
> }
>
> -static void gen6_rps_init(struct intel_rps *rps)
> +static u32 intel_rps_read_state_cap(struct intel_rps *rps)
> {
> struct drm_i915_private *i915 = rps_to_i915(rps);
> - u32 rp_state_cap = intel_rps_read_state_cap(rps);
> + struct intel_uncore *uncore = rps_to_uncore(rps);
>
> - /* All of these values are in units of 50MHz */
> + if (IS_XEHPSDV(i915))
> + return intel_uncore_read(uncore, XEHPSDV_RP_STATE_CAP);
> + else if (IS_GEN9_LP(i915))
> + return intel_uncore_read(uncore, BXT_RP_STATE_CAP);
> + else
> + return intel_uncore_read(uncore, GEN6_RP_STATE_CAP); }
> +
> +/**
> + * gen6_rps_get_freq_caps - Get freq caps exposed by HW
> + * @rps: the intel_rps structure
> + * @caps: returned freq caps
> + *
> + * Returned "caps" frequencies should be converted to MHz using
> + * intel_gpu_freq()
> + */
> +void gen6_rps_get_freq_caps(struct intel_rps *rps, struct
> +intel_rps_freq_caps *caps) {
> + struct drm_i915_private *i915 = rps_to_i915(rps);
> + u32 rp_state_cap;
> +
> + rp_state_cap = intel_rps_read_state_cap(rps);
>
> /* static values from HW: RP0 > RP1 > RPn (min_freq) */
> if (IS_GEN9_LP(i915)) {
> - rps->rp0_freq = (rp_state_cap >> 16) & 0xff;
> - rps->rp1_freq = (rp_state_cap >> 8) & 0xff;
> - rps->min_freq = (rp_state_cap >> 0) & 0xff;
> + caps->rp0_freq = (rp_state_cap >> 16) & 0xff;
> + caps->rp1_freq = (rp_state_cap >> 8) & 0xff;
> + caps->min_freq = (rp_state_cap >> 0) & 0xff;
> } else {
> - rps->rp0_freq = (rp_state_cap >> 0) & 0xff;
> - rps->rp1_freq = (rp_state_cap >> 8) & 0xff;
> - rps->min_freq = (rp_state_cap >> 16) & 0xff;
> + caps->rp0_freq = (rp_state_cap >> 0) & 0xff;
> + caps->rp1_freq = (rp_state_cap >> 8) & 0xff;
> + caps->min_freq = (rp_state_cap >> 16) & 0xff;
> }
>
> + if (IS_GEN9_BC(i915) || GRAPHICS_VER(i915) >= 11) {
> + /*
> + * In this case rp_state_cap register reports frequencies in
> + * units of 50 MHz. Convert these to the actual "hw unit", i.e.
> + * units of 16.67 MHz
> + */
> + caps->rp0_freq *= GEN9_FREQ_SCALER;
> + caps->rp1_freq *= GEN9_FREQ_SCALER;
> + caps->min_freq *= GEN9_FREQ_SCALER;
> + }
> +}
> +
> +static void gen6_rps_init(struct intel_rps *rps) {
> + struct drm_i915_private *i915 = rps_to_i915(rps);
> + struct intel_rps_freq_caps caps;
> +
> + gen6_rps_get_freq_caps(rps, &caps);
> + rps->rp0_freq = caps.rp0_freq;
> + rps->rp1_freq = caps.rp1_freq;
> + rps->min_freq = caps.min_freq;
> +
> /* hw_max = RP0 until we check for overclocking */
> rps->max_freq = rps->rp0_freq;
>
> @@ -1095,26 +1138,18 @@ static void gen6_rps_init(struct intel_rps *rps)
> if (IS_HASWELL(i915) || IS_BROADWELL(i915) ||
> IS_GEN9_BC(i915) || GRAPHICS_VER(i915) >= 11) {
> u32 ddcc_status = 0;
> + u32 mult = 1;
>
> + if (IS_GEN9_BC(i915) || GRAPHICS_VER(i915) >= 11)
> + mult = GEN9_FREQ_SCALER;
> if (snb_pcode_read(i915,
> HSW_PCODE_DYNAMIC_DUTY_CYCLE_CONTROL,
> &ddcc_status, NULL) == 0)
> rps->efficient_freq =
> - clamp_t(u8,
> - (ddcc_status >> 8) & 0xff,
> + clamp_t(u32,
> + ((ddcc_status >> 8) & 0xff) * mult,
> rps->min_freq,
> rps->max_freq);
> }
> -
> - if (IS_GEN9_BC(i915) || GRAPHICS_VER(i915) >= 11) {
> - /* Store the frequency values in 16.66 MHZ units, which is
> - * the natural hardware unit for SKL
> - */
> - rps->rp0_freq *= GEN9_FREQ_SCALER;
> - rps->rp1_freq *= GEN9_FREQ_SCALER;
> - rps->min_freq *= GEN9_FREQ_SCALER;
> - rps->max_freq *= GEN9_FREQ_SCALER;
> - rps->efficient_freq *= GEN9_FREQ_SCALER;
> - }
> }
>
> static bool rps_reset(struct intel_rps *rps) @@ -2219,19 +2254,6 @@ int
> intel_rps_set_min_frequency(struct intel_rps *rps, u32 val)
> return set_min_freq(rps, val);
> }
>
> -u32 intel_rps_read_state_cap(struct intel_rps *rps) -{
> - struct drm_i915_private *i915 = rps_to_i915(rps);
> - struct intel_uncore *uncore = rps_to_uncore(rps);
> -
> - if (IS_XEHPSDV(i915))
> - return intel_uncore_read(uncore, XEHPSDV_RP_STATE_CAP);
> - else if (IS_GEN9_LP(i915))
> - return intel_uncore_read(uncore, BXT_RP_STATE_CAP);
> - else
> - return intel_uncore_read(uncore, GEN6_RP_STATE_CAP);
> -}
> -
> static void intel_rps_set_manual(struct intel_rps *rps, bool enable) {
> struct intel_uncore *uncore = rps_to_uncore(rps); @@ -2244,18
> +2266,18 @@ static void intel_rps_set_manual(struct intel_rps *rps, bool
> enable) void intel_rps_raise_unslice(struct intel_rps *rps) {
> struct intel_uncore *uncore = rps_to_uncore(rps);
> - u32 rp0_unslice_req;
>
> mutex_lock(&rps->lock);
>
> if (rps_uses_slpc(rps)) {
> /* RP limits have not been initialized yet for SLPC path */
> - rp0_unslice_req = ((intel_rps_read_state_cap(rps) >> 0)
> - & 0xff) * GEN9_FREQ_SCALER;
> + struct intel_rps_freq_caps caps;
> +
> + gen6_rps_get_freq_caps(rps, &caps);
>
> intel_rps_set_manual(rps, true);
> intel_uncore_write(uncore, GEN6_RPNSWREQ,
> - ((rp0_unslice_req <<
> + ((caps.rp0_freq <<
> GEN9_SW_REQ_UNSLICE_RATIO_SHIFT) |
> GEN9_IGNORE_SLICE_RATIO));
> intel_rps_set_manual(rps, false);
> @@ -2269,18 +2291,18 @@ void intel_rps_raise_unslice(struct intel_rps *rps)
> void intel_rps_lower_unslice(struct intel_rps *rps) {
> struct intel_uncore *uncore = rps_to_uncore(rps);
> - u32 rpn_unslice_req;
>
> mutex_lock(&rps->lock);
>
> if (rps_uses_slpc(rps)) {
> /* RP limits have not been initialized yet for SLPC path */
> - rpn_unslice_req = ((intel_rps_read_state_cap(rps) >> 16)
> - & 0xff) * GEN9_FREQ_SCALER;
> + struct intel_rps_freq_caps caps;
> +
> + gen6_rps_get_freq_caps(rps, &caps);
>
> intel_rps_set_manual(rps, true);
> intel_uncore_write(uncore, GEN6_RPNSWREQ,
> - ((rpn_unslice_req <<
> + ((caps.min_freq <<
> GEN9_SW_REQ_UNSLICE_RATIO_SHIFT) |
> GEN9_IGNORE_SLICE_RATIO));
> intel_rps_set_manual(rps, false);
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.h
> b/drivers/gpu/drm/i915/gt/intel_rps.h
> index ba1ed9f7ecda..1e8d56491308 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.h
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.h
> @@ -45,7 +45,7 @@ u32 intel_rps_get_rp1_frequency(struct intel_rps *rps);
> u32 intel_rps_get_rpn_frequency(struct intel_rps *rps);
> u32 intel_rps_read_punit_req(struct intel_rps *rps);
> u32 intel_rps_read_punit_req_frequency(struct intel_rps *rps);
> -u32 intel_rps_read_state_cap(struct intel_rps *rps);
> +void gen6_rps_get_freq_caps(struct intel_rps *rps, struct
> +intel_rps_freq_caps *caps);
> void intel_rps_raise_unslice(struct intel_rps *rps); void
> intel_rps_lower_unslice(struct intel_rps *rps);
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps_types.h
> b/drivers/gpu/drm/i915/gt/intel_rps_types.h
> index 3941d8551f52..9173ec75f2b8 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps_types.h
> +++ b/drivers/gpu/drm/i915/gt/intel_rps_types.h
> @@ -37,6 +37,21 @@ enum {
> INTEL_RPS_TIMER,
> };
>
> +/**
> + * struct intel_rps_freq_caps - rps freq capabilities
> + * @rp0_freq: non-overclocked max frequency
> + * @rp1_freq: "less than" RP0 power/freqency
> + * @min_freq: aka RPn, minimum frequency
> + *
> + * Freq caps exposed by HW, values are in "hw units" and
> +intel_gpu_freq()
> + * should be used to convert to MHz
> + */
> +struct intel_rps_freq_caps {
> + u8 rp0_freq;
> + u8 rp1_freq;
> + u8 min_freq;
> +};
> +
> struct intel_rps {
> struct mutex lock; /* protects enabling and the worker */
>
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> index 9f032c65a488..9e02355e44f1 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c
> @@ -582,16 +582,12 @@ static int slpc_use_fused_rp0(struct intel_guc_slpc
> *slpc) static void slpc_get_rp_values(struct intel_guc_slpc *slpc) {
> struct intel_rps *rps = &slpc_to_gt(slpc)->rps;
> - u32 rp_state_cap;
> + struct intel_rps_freq_caps caps;
>
> - rp_state_cap = intel_rps_read_state_cap(rps);
> -
> - slpc->rp0_freq = REG_FIELD_GET(RP0_CAP_MASK, rp_state_cap) *
> - GT_FREQUENCY_MULTIPLIER;
> - slpc->rp1_freq = REG_FIELD_GET(RP1_CAP_MASK, rp_state_cap) *
> - GT_FREQUENCY_MULTIPLIER;
> - slpc->min_freq = REG_FIELD_GET(RPN_CAP_MASK, rp_state_cap) *
> - GT_FREQUENCY_MULTIPLIER;
> + gen6_rps_get_freq_caps(rps, &caps);
> + slpc->rp0_freq = intel_gpu_freq(rps, caps.rp0_freq);
> + slpc->rp1_freq = intel_gpu_freq(rps, caps.rp1_freq);
> + slpc->min_freq = intel_gpu_freq(rps, caps.min_freq);
>
> if (!slpc->boost_freq)
> slpc->boost_freq = slpc->rp0_freq;
> --
> 2.34.1
