On Fri, Dec 13, 2019 at 04:12:30PM +0200, Stanislav Lisovskiy wrote:
> According to BSpec 53998, we should try to
> restrict qgv points, which can't provide
> enough bandwidth for desired display configuration.
>
> Currently we are just comparing against all of
> those and take minimum(worst case).
>
> v2: Fixed wrong PCode reply mask, removed hardcoded
> values.
>
> v3: Forbid simultaneous legacy SAGV PCode requests and
> restricting qgv points. Put the actual restriction
> to commit function, added serialization(thanks to Ville)
> to prevent commit being applied out of order in case of
> nonblocking and/or nomodeset commits.
>
> v4:
> - Minor code refactoring, fixed few typos(thanks to James Ausmus)
> - Change the naming of qgv point
> masking/unmasking functions(James Ausmus).
> - Simplify the masking/unmasking operation itself,
> as we don't need to mask only single point per request(James Ausmus)
> - Reject and stick to highest bandwidth point if SAGV
> can't be enabled(BSpec)
>
> v5:
> - Add new mailbox reply codes, which seems to happen during boot
> time for TGL and indicate that QGV setting is not yet available.
>
> v6:
> - Increase number of supported QGV points to be in sync with BSpec.
>
> v7: - Rebased and resolved conflict to fix build failure.
> - Fix NUM_QGV_POINTS to 8 and moved that to header file(James Ausmus)
>
> v8: - Don't report an error if we can't restrict qgv points, as SAGV
> can be disabled by BIOS, which is completely legal. So don't
> make CI panic. Instead if we detect that there is only 1 QGV
> point accessible just analyze if we can fit the required bandwidth
> requirements, but no need in restricting.
>
> v9: - Fix wrong QGV transition if we have 0 planes and no SAGV
> simultaneously.
>
> v10: - Fix CDCLK corruption, because of global state getting serialized
> without modeset, which caused copying of non-calculated cdclk
> to be copied to dev_priv(thanks to Ville for the hint).
>
> v11: - Remove unneeded headers and spaces(Matthew Roper)
> - Remove unneeded intel_qgv_info qi struct from bw check and zero
> out the needed one(Matthew Roper)
> - Changed QGV error message to have more clear meaning(Matthew Roper)
> - Use state->modeset_set instead of any_ms(Matthew Roper)
> - Moved NUM_SAGV_POINTS from i915_reg.h to i915_drv.h where it's used
> - Keep using crtc_state->hw.active instead of .enable(Matthew Roper)
> - Moved unrelated changes to other patch(using latency as parameter
> for plane wm calculation, moved to SAGV refactoring patch)
>
> v12: - Fix rebase conflict with own temporary SAGV/QGV fix.
> - Remove unnecessary mask being zero check when unmasking
> qgv points as this is completely legal(Matt Roper)
> - Check if we are setting the same mask as already being set
> in hardware to prevent error from PCode.
> - Fix error message when restricting/unrestricting qgv points
> to "mask/unmask" which sounds more accurate(Matt Roper)
> - Move sagv status setting to icl_get_bw_info from atomic check
> as this should be calculated only once.(Matt Roper)
> - Edited comments for the case when we can't enable SAGV and
> use only 1 QGV point with highest bandwidth to be more
> understandable.(Matt Roper)
>
> Reviewed-by: James Ausmus <james.aus...@intel.com>
> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovs...@intel.com>
> Cc: Ville Syrjälä <ville.syrj...@intel.com>
> Cc: James Ausmus <james.aus...@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_bw.c | 144 +++++++++++++-----
> drivers/gpu/drm/i915/display/intel_bw.h | 2 +
> drivers/gpu/drm/i915/display/intel_display.c | 87 ++++++++++-
> .../drm/i915/display/intel_display_types.h | 3 +
> drivers/gpu/drm/i915/i915_drv.h | 5 +
> drivers/gpu/drm/i915/i915_reg.h | 5 +
> drivers/gpu/drm/i915/intel_sideband.c | 27 +++-
> 7 files changed, 233 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bw.c
> b/drivers/gpu/drm/i915/display/intel_bw.c
> index dcb66a33be9b..95d8d7dfa769 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.c
> +++ b/drivers/gpu/drm/i915/display/intel_bw.c
> @@ -8,6 +8,9 @@
> #include "intel_bw.h"
> #include "intel_display_types.h"
> #include "intel_sideband.h"
> +#include "intel_atomic.h"
> +#include "intel_pm.h"
> +
>
> /* Parameters for Qclk Geyserville (QGV) */
> struct intel_qgv_point {
> @@ -113,6 +116,26 @@ static int icl_pcode_read_qgv_point_info(struct
> drm_i915_private *dev_priv,
> return 0;
> }
>
> +int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv,
> + u32 points_mask)
> +{
> + int ret;
> +
> + /* bspec says to keep retrying for at least 1 ms */
> + ret = skl_pcode_request(dev_priv, ICL_PCODE_SAGV_DE_MEM_SS_CONFIG,
> + points_mask,
> + GEN11_PCODE_POINTS_RESTRICTED_MASK,
> + GEN11_PCODE_POINTS_RESTRICTED,
> + 1);
> +
> + if (ret < 0) {
> + DRM_ERROR("Failed to disable qgv points (%d)\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
> struct intel_qgv_info *qi)
> {
> @@ -236,6 +259,16 @@ static int icl_get_bw_info(struct drm_i915_private
> *dev_priv, const struct intel
> break;
> }
>
> + /*
> + * In case if SAGV is disabled in BIOS, we always get 1
> + * SAGV point, but we can't send PCode commands to restrict it
> + * as it will fail and pointless anyway.
> + */
> + if (qi.num_points == 1)
> + dev_priv->sagv_status = I915_SAGV_NOT_CONTROLLED;
> + else
> + dev_priv->sagv_status = I915_SAGV_ENABLED;
> +
> return 0;
> }
>
> @@ -273,34 +306,6 @@ void intel_bw_init_hw(struct drm_i915_private *dev_priv)
> icl_get_bw_info(dev_priv, &icl_sa_info);
> }
>
> -static unsigned int intel_max_data_rate(struct drm_i915_private *dev_priv,
> - int num_planes)
> -{
> - if (INTEL_GEN(dev_priv) >= 11) {
> - /*
> - * Any bw group has same amount of QGV points
> - */
> - const struct intel_bw_info *bi =
> - &dev_priv->max_bw[0];
> - unsigned int min_bw = UINT_MAX;
> - int i;
> -
> - /*
> - * FIXME with SAGV disabled maybe we can assume
> - * point 1 will always be used? Seems to match
> - * the behaviour observed in the wild.
> - */
> - for (i = 0; i < bi->num_qgv_points; i++) {
> - unsigned int bw = icl_max_bw(dev_priv, num_planes, i);
> -
> - min_bw = min(bw, min_bw);
> - }
> - return min_bw;
> - } else {
> - return UINT_MAX;
> - }
> -}
> -
> static unsigned int intel_bw_crtc_num_active_planes(const struct
> intel_crtc_state *crtc_state)
> {
> /*
> @@ -392,7 +397,11 @@ int intel_bw_atomic_check(struct intel_atomic_state
> *state)
> unsigned int data_rate, max_data_rate;
> unsigned int num_active_planes;
> struct intel_crtc *crtc;
> - int i;
> + int i, ret;
> + u32 allowed_points = 0;
> + unsigned int max_bw_point = 0, max_bw = 0;
> + unsigned int num_qgv_points = dev_priv->max_bw[0].num_qgv_points;
> + u32 mask = (1 << num_qgv_points) - 1;
>
> /* FIXME earlier gens need some checks too */
> if (INTEL_GEN(dev_priv) < 11)
> @@ -436,16 +445,83 @@ int intel_bw_atomic_check(struct intel_atomic_state
> *state)
> data_rate = intel_bw_data_rate(dev_priv, bw_state);
> num_active_planes = intel_bw_num_active_planes(dev_priv, bw_state);
>
> - max_data_rate = intel_max_data_rate(dev_priv, num_active_planes);
> -
> data_rate = DIV_ROUND_UP(data_rate, 1000);
>
> - if (data_rate > max_data_rate) {
> - DRM_DEBUG_KMS("Bandwidth %u MB/s exceeds max available %d MB/s
> (%d active planes)\n",
> - data_rate, max_data_rate, num_active_planes);
> + for (i = 0; i < num_qgv_points; i++) {
> + max_data_rate = icl_max_bw(dev_priv, num_active_planes, i);
max_data_rate no longer needed outside the loop, so should move the
declaration in.
> + /*
> + * We need to know which qgv point gives us
> + * maximum bandwidth in order to disable SAGV
> + * if we find that we exceed SAGV block time
> + * with watermarks. By that moment we already
> + * have those, as it is calculated earlier in
> + * intel_atomic_check,
> + */
> + if (max_data_rate > max_bw) {
> + max_bw_point = i;
> + max_bw = max_data_rate;
> + }
> + if (max_data_rate >= data_rate)
> + allowed_points |= BIT(i);
Seems a bit redundant having both 'mask' and 'allowed_points'.
Could flip it around and just do:
allowed_points = (1<<num_points)-1;
for() {
if (data_rate > max)
allowed_points &= ~BIT(i)
}
> + DRM_DEBUG_KMS("QGV point %d: max bw %d required %d\n",
> + i, max_data_rate, data_rate);
> + }
> +
> + /*
> + * BSpec states that we always should have at least one allowed point
> + * left, so if we couldn't - simply reject the configuration for obvious
> + * reasons.
> + */
> + if (allowed_points == 0) {
> + DRM_DEBUG_KMS("No QGV points provide sufficient memory"
> + " bandwidth for display configuration.\n");
> return -EINVAL;
> }
>
> + /*
> + * Leave only single point with highest bandwidth, if
> + * we can't enable SAGV due to the increased memory latency it may
> + * cause.
> + */
> + if (!intel_can_enable_sagv(state)) {
> + /*
> + * This is a special case, when we have 0 planes
> + * and SAGV can't be enabled means that we should keep QGV with
> + * highest bandwidth, however algorithm returns wrong result
> + * for 0 planes and 0 data rate case, so just stick to last
> config
> + * then. Otherwise use the QGV point with highest BW according
> + * to BSpec.
> + */
> + if (!data_rate && !num_active_planes) {
Why would we need to special case this? AFAICS max_bw_point should be
valid regardless. We could also precompute it at init time and stuff
it into dev_priv alongside the res of the bw stuff.
> + DRM_DEBUG_KMS("No SAGV, using old QGV mask\n");
> + allowed_points = (~dev_priv->qgv_points_mask) & mask;
> + } else {
> + allowed_points = 1 << max_bw_point;
> + DRM_DEBUG_KMS("No SAGV, using single QGV point %d\n",
> + max_bw_point);
> + }
> + }
> + /*
> + * We store the ones which need to be masked as that is what PCode
> + * actually accepts as a parameter.
> + */
> + state->qgv_points_mask = (~allowed_points) & mask;
Ah we need to invert it. I guess we do need two variables then.
Though we could just compute it as inverted already and then check
if (qgv_points_mask == all_qgv_points)
return -EINVAL;
> +
> + DRM_DEBUG_KMS("New state %p qgv mask %x\n",
> + state, state->qgv_points_mask);
> +
> + /*
> + * If the actual mask had changed we need to make sure that
> + * the commits are serialized(in case this is a nomodeset, nonblocking)
> + */
> + if (state->qgv_points_mask != dev_priv->qgv_points_mask) {
> + ret = intel_atomic_serialize_global_state(state);
> + if (ret) {
> + DRM_DEBUG_KMS("Could not serialize global state\n");
> + return ret;
> + }
> + }
> +
> return 0;
> }
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bw.h
> b/drivers/gpu/drm/i915/display/intel_bw.h
> index 9db10af012f4..66bf9bc10b73 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.h
> +++ b/drivers/gpu/drm/i915/display/intel_bw.h
> @@ -28,5 +28,7 @@ int intel_bw_init(struct drm_i915_private *dev_priv);
> int intel_bw_atomic_check(struct intel_atomic_state *state);
> void intel_bw_crtc_update(struct intel_bw_state *bw_state,
> const struct intel_crtc_state *crtc_state);
> +int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv,
> + u32 points_mask);
>
> #endif /* __INTEL_BW_H__ */
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> b/drivers/gpu/drm/i915/display/intel_display.c
> index d58c70fbc08e..92f2db6358f3 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -14689,6 +14689,75 @@ static void intel_atomic_cleanup_work(struct
> work_struct *work)
> intel_atomic_helper_free_state(i915);
> }
>
> +static void intel_qgv_points_mask(struct intel_atomic_state *state)
> +{
> + struct drm_device *dev = state->base.dev;
> + struct drm_i915_private *dev_priv = to_i915(dev);
> + int ret;
> + u32 new_mask = dev_priv->qgv_points_mask | state->qgv_points_mask;
> + unsigned int num_qgv_points = dev_priv->max_bw[0].num_qgv_points;
> + unsigned int mask = (1 << num_qgv_points) - 1;
> +
> + /*
> + * As we don't know initial hardware state during initial commit
> + * we should not do anything, until we actually figure out,
> + * what are the qgv points to mask.
> + */
> + if (!new_mask)
> + return;
How can we get here with zero _new_ mask? We should have computed it
already.
> +
> + WARN_ON(new_mask == mask);
> +
> + /*
> + * Just return if we can't control SAGV or don't have it.
> + */
> + if (!intel_has_sagv(dev_priv))
> + return;
> +
> + /*
> + * Restrict required qgv points before updating the configuration.
> + * According to BSpec we can't mask and unmask qgv points at the same
> + * time. Also masking should be done before updating the configuration
> + * and unmasking afterwards.
> + */
> + ret = icl_pcode_restrict_qgv_points(dev_priv, new_mask);
> + if (ret < 0)
> + DRM_DEBUG_KMS("Could not mask required qgv points(%d)\n",
> + ret);
> + else
> + dev_priv->qgv_points_mask = new_mask;
We should not frob this here. It should only be changed at swap_state().
> +}
> +
> +static void intel_qgv_points_unmask(struct intel_atomic_state *state)
> +{
> + struct drm_device *dev = state->base.dev;
> + struct drm_i915_private *dev_priv = to_i915(dev);
> + int ret;
> + u32 new_mask = dev_priv->qgv_points_mask & state->qgv_points_mask;
Shouldn't that just be the new mask and not old&new?
> +
> + /*
> + * Just return if we can't control SAGV or don't have it.
> + */
> + if (!intel_has_sagv(dev_priv))
> + return;
> +
> + if (new_mask == dev_priv->qgv_points_mask)
> + return;
> +
> + /*
> + * Allow required qgv points after updating the configuration.
> + * According to BSpec we can't mask and unmask qgv points at the same
> + * time. Also masking should be done before updating the configuration
> + * and unmasking afterwards.
> + */
> + ret = icl_pcode_restrict_qgv_points(dev_priv, new_mask);
> + if (ret < 0)
> + DRM_DEBUG_KMS("Could not unmask required qgv points(%d)\n",
> + ret);
> + else
> + dev_priv->qgv_points_mask = new_mask;
> +}
> +
> static void intel_atomic_commit_tail(struct intel_atomic_state *state)
> {
> struct drm_device *dev = state->base.dev;
> @@ -14716,6 +14785,9 @@ static void intel_atomic_commit_tail(struct
> intel_atomic_state *state)
> }
> }
>
> + if ((INTEL_GEN(dev_priv) >= 11))
> + intel_qgv_points_mask(state);
Hmm. Why isn't this next to the sagv disable?
> +
> intel_commit_modeset_disables(state);
>
> /* FIXME: Eventually get rid of our crtc->config pointer */
> @@ -14734,8 +14806,9 @@ static void intel_atomic_commit_tail(struct
> intel_atomic_state *state)
> * SKL workaround: bspec recommends we disable the SAGV when we
> * have more then one pipe enabled
> */
> - if (!intel_can_enable_sagv(state))
> - intel_disable_sagv(dev_priv);
> + if (INTEL_GEN(dev_priv) < 11)
> + if (!intel_can_enable_sagv(state))
> + intel_disable_sagv(dev_priv);
>
> intel_modeset_verify_disabled(dev_priv, state);
> }
> @@ -14832,8 +14905,12 @@ static void intel_atomic_commit_tail(struct
> intel_atomic_state *state)
> if (state->modeset)
> intel_verify_planes(state);
>
> - if (state->modeset && intel_can_enable_sagv(state))
> - intel_enable_sagv(dev_priv);
> + if (INTEL_GEN(dev_priv) < 11) {
> + if (state->modeset && intel_can_enable_sagv(state))
> + intel_enable_sagv(dev_priv);
> + } else {
> + intel_qgv_points_unmask(state);
> + }
>
> drm_atomic_helper_commit_hw_done(&state->base);
>
> @@ -14980,7 +15057,7 @@ static int intel_atomic_commit(struct drm_device *dev,
> intel_shared_dpll_swap_state(state);
> intel_atomic_track_fbs(state);
>
> - if (state->global_state_changed) {
> + if (state->global_state_changed && state->modeset) {
> assert_global_state_locked(dev_priv);
>
> memcpy(dev_priv->min_cdclk, state->min_cdclk,
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 5301e1042b40..e1ac7c01bbda 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -528,6 +528,9 @@ struct intel_atomic_state {
> struct i915_sw_fence commit_ready;
>
> struct llist_node freed;
> +
> + /* Gen11+ only */
> + u32 qgv_points_mask;
u8 seems sufficient. Pls pack it next to some other u8 semi-related
stuff if possible so we can try to avoid extra holes.
> };
>
> struct intel_plane_state {
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index b877c42213c4..ac9690d98910 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -850,6 +850,9 @@ enum intel_pipe_crc_source {
> INTEL_PIPE_CRC_SOURCE_MAX,
> };
>
> +/* BSpec precisely defines this */
> +#define NUM_SAGV_POINTS 8
> +
> #define INTEL_PIPE_CRC_ENTRIES_NR 128
> struct intel_pipe_crc {
> spinlock_t lock;
> @@ -1244,6 +1247,8 @@ struct drm_i915_private {
> u8 num_planes;
> } max_bw[6];
>
> + u32 qgv_points_mask;
> +
> struct drm_private_obj bw_obj;
>
> struct intel_runtime_pm runtime_pm;
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 17f9dd3bda72..0a55bd529fbb 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -8999,6 +8999,8 @@ enum {
> #define GEN6_PCODE_UNIMPLEMENTED_CMD 0xFF
> #define GEN7_PCODE_TIMEOUT 0x2
> #define GEN7_PCODE_ILLEGAL_DATA 0x3
> +#define GEN11_PCODE_MAIL_BOX_LOCKED 0x6
> +#define GEN11_PCODE_REJECTED 0x11
> #define GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE 0x10
> #define GEN6_PCODE_WRITE_RC6VIDS 0x4
> #define GEN6_PCODE_READ_RC6VIDS 0x5
> @@ -9020,6 +9022,7 @@ enum {
> #define ICL_PCODE_MEM_SUBSYSYSTEM_INFO 0xd
> #define ICL_PCODE_MEM_SS_READ_GLOBAL_INFO (0x0 << 8)
> #define ICL_PCODE_MEM_SS_READ_QGV_POINT_INFO(point) (((point) <<
> 16) | (0x1 << 8))
> +#define ICL_PCODE_SAGV_DE_MEM_SS_CONFIG 0xe
> #define GEN6_PCODE_READ_D_COMP 0x10
> #define GEN6_PCODE_WRITE_D_COMP 0x11
> #define HSW_PCODE_DE_WRITE_FREQ_REQ 0x17
> @@ -9032,6 +9035,8 @@ enum {
> #define GEN9_SAGV_IS_DISABLED 0x1
> #define GEN9_SAGV_ENABLE 0x3
> #define GEN12_PCODE_READ_SAGV_BLOCK_TIME_US 0x23
> +#define GEN11_PCODE_POINTS_RESTRICTED 0x0
> +#define GEN11_PCODE_POINTS_RESTRICTED_MASK 0x1
> #define GEN6_PCODE_DATA _MMIO(0x138128)
> #define GEN6_PCODE_FREQ_IA_RATIO_SHIFT 8
> #define GEN6_PCODE_FREQ_RING_RATIO_SHIFT 16
> diff --git a/drivers/gpu/drm/i915/intel_sideband.c
> b/drivers/gpu/drm/i915/intel_sideband.c
> index e06b35b844a0..ff9dbed094d8 100644
> --- a/drivers/gpu/drm/i915/intel_sideband.c
> +++ b/drivers/gpu/drm/i915/intel_sideband.c
> @@ -371,6 +371,29 @@ static inline int gen7_check_mailbox_status(u32 mbox)
> }
> }
>
> +static inline int gen11_check_mailbox_status(u32 mbox)
> +{
> + switch (mbox & GEN6_PCODE_ERROR_MASK) {
> + case GEN6_PCODE_SUCCESS:
> + return 0;
> + case GEN6_PCODE_ILLEGAL_CMD:
> + return -ENXIO;
> + case GEN7_PCODE_TIMEOUT:
> + return -ETIMEDOUT;
> + case GEN7_PCODE_ILLEGAL_DATA:
> + return -EINVAL;
> + case GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE:
> + return -EOVERFLOW;
> + case GEN11_PCODE_MAIL_BOX_LOCKED:
> + return -EAGAIN;
Do we really expect it to work if we retry?
> + case GEN11_PCODE_REJECTED:
> + return -EACCES;
These things don't seem to conflict with the gen7 stuff so could
probably just stuff them into the gen7 function. In any case this
pcode change should be a separate patch.
> + default:
> + MISSING_CASE(mbox & GEN6_PCODE_ERROR_MASK);
> + return 0;
> + }
> +}
> +
> static int __sandybridge_pcode_rw(struct drm_i915_private *i915,
> u32 mbox, u32 *val, u32 *val1,
> int fast_timeout_us,
> @@ -408,7 +431,9 @@ static int __sandybridge_pcode_rw(struct drm_i915_private
> *i915,
> if (is_read && val1)
> *val1 = intel_uncore_read_fw(uncore, GEN6_PCODE_DATA1);
>
> - if (INTEL_GEN(i915) > 6)
> + if (INTEL_GEN(i915) >= 11)
> + return gen11_check_mailbox_status(mbox);
> + else if (INTEL_GEN(i915) > 6)
> return gen7_check_mailbox_status(mbox);
> else
> return gen6_check_mailbox_status(mbox);
> --
> 2.17.1
--
Ville Syrjälä
Intel
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
