[PATCH 1/2] drm/i915/watermark: Refactor dpkgc code
Govindapillai, Vinod
vinod.govindapillai at intel.com
Thu Nov 14 12:41:46 UTC 2024
Hi,
I guess this is mostly ok. But some minor comments...
On Thu, 2024-11-14 at 10:00 +0530, Suraj Kandpal wrote:
> We move our dpkgc function for the below reasons:
> - We want to make sure we have all the required values specially
> linetime which is computed after intel_wm_compute, this will also
> help implement some WA's which require linetime.
> -We do not want to write into any registers during compute_config phase
> While we are at it do some more refactors in the function like:
> -Use intel_display wherever possible
> -Move away from using enable_dpkgc bool and call it fixed_refresh_rate
> -Optimize value prepration
>
> --v2
> -No need to save anything in intel_display structure [Vinod]
> -Move computation and writing into register to intel_atomic_commit_tail
> [Vinod]
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>
Probably some better clarity on the subject Something like
drm/i915/display: Refactor handling of dpkgc latency programming
Btw, i didn't find any patches with "drm/i915/watermark" on git log.
> ---
> drivers/gpu/drm/i915/display/intel_display.c | 2 +
> drivers/gpu/drm/i915/display/intel_wm.c | 57 ++++++++++++++++++++
> drivers/gpu/drm/i915/display/intel_wm.h | 2 +
> drivers/gpu/drm/i915/display/skl_watermark.c | 52 ------------------
> 4 files changed, 61 insertions(+), 52 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> b/drivers/gpu/drm/i915/display/intel_display.c
> index e790a2de5b3d..4f8e45a794bb 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -7826,6 +7826,8 @@ static void intel_atomic_commit_tail(struct intel_atomic_state *state)
> /* Now enable the clocks, plane, pipe, and connectors that we set up. */
> dev_priv->display.funcs.display->commit_modeset_enables(state);
>
> + intel_program_dpkgc_latency(state, dev_priv);
"dev_priv" is redundant here as we are supposed to use intel_display and you can get display from
to_intel_display(state) in intel_program_dpkgc_latency
> if (state->modeset)
> intel_set_cdclk_post_plane_update(state);
>
> diff --git a/drivers/gpu/drm/i915/display/intel_wm.c b/drivers/gpu/drm/i915/display/intel_wm.c
> index d7dc49aecd27..620873d1244f 100644
> --- a/drivers/gpu/drm/i915/display/intel_wm.c
> +++ b/drivers/gpu/drm/i915/display/intel_wm.c
> @@ -7,9 +7,18 @@
>
> #include "i915_drv.h"
> #include "i9xx_wm.h"
> +#include "intel_de.h"
> #include "intel_display_types.h"
> #include "intel_wm.h"
> #include "skl_watermark.h"
> +#include "skl_watermark_regs.h"
> +
> +/*
> + * It is expected that DSB can do posted writes to every register in
> + * the pipe and planes within 100us. For flip queue use case, the
> + * recommended DSB execution time is 100us + one SAGV block time.
> + */
> +#define DSB_EXE_TIME 100
>
> /**
> * intel_update_watermarks - update FIFO watermark values based on current modes
> @@ -131,6 +140,54 @@ bool intel_wm_plane_visible(const struct intel_crtc_state *crtc_state,
> return plane_state->uapi.visible;
> }
>
> +/*
> + * If Fixed Refresh Rate or For VRR case Vmin = Vmax = Flipline:
> + * Program DEEP PKG_C_LATENCY Pkg C with highest valid latency from
> + * watermark level1 and up and above. If watermark level 1 is
> + * invalid program it with all 1's.
> + * Program PKG_C_LATENCY Added Wake Time = DSB execution time
> + * If Variable Refresh Rate where Vmin != Vmax != Flipline:
> + * Program DEEP PKG_C_LATENCY Pkg C with all 1's.
> + * Program PKG_C_LATENCY Added Wake Time = 0
> + */
> +void
> +intel_program_dpkgc_latency(struct intel_atomic_state *state,
> + struct drm_i915_private *i915)
> +{
> + struct intel_display *display = to_intel_display(state);
> + struct intel_crtc *crtc;
> + struct intel_crtc_state *new_crtc_state;
> + u32 max_latency = LNL_PKG_C_LATENCY_MASK;
> + u32 clear = 0, val = 0;
No need to init these.
> + u32 added_waketime = 0;
> + int i;
> + bool fixed_refresh_rate = false;
Also pls place those variable declarations with initializations first and then the rest.
> +
> + if (DISPLAY_VER(display) < 20)
> + return;
> +
> + for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
> + if ((new_crtc_state->vrr.vmin == new_crtc_state->vrr.vmax &&
> + new_crtc_state->vrr.vmin == new_crtc_state->vrr.flipline) ||
> + !new_crtc_state->vrr.enable)
I assume new_crtc_state->vrr.vmin/vmax/flipline etc are valid only if new_crtc_state->vrr.enable is
true. I guess then it is better to keep the !new_crtc_state->vrr.enable as first condition
if (!new_crtc_state->vrr.enable || (new_crtc_state->vrr.vmin == new_crtc_state->vrr.vmax &&
new_crtc_state->vrr.vmin == new_crtc_state->vrr.flipline)) )
> + fixed_refresh_rate = true;
> + }
> +
> + if (fixed_refresh_rate) {
> + max_latency = skl_watermark_max_latency(i915, 1);
> + if (max_latency == 0)
> + max_latency = LNL_PKG_C_LATENCY_MASK;
> + added_waketime = DSB_EXE_TIME +
> + display->sagv.block_time_us;
> + }
> +
> + clear |= LNL_ADDED_WAKE_TIME_MASK | LNL_PKG_C_LATENCY_MASK;
> + val |= REG_FIELD_PREP(LNL_PKG_C_LATENCY_MASK, max_latency) |
> + REG_FIELD_PREP(LNL_ADDED_WAKE_TIME_MASK, added_waketime);
As mentioned before you don't need |= in these above statements
> +
> + intel_de_rmw(display, LNL_PKG_C_LATENCY, clear, val);
> +}
> +
> void intel_print_wm_latency(struct drm_i915_private *dev_priv,
> const char *name, const u16 wm[])
> {
> diff --git a/drivers/gpu/drm/i915/display/intel_wm.h b/drivers/gpu/drm/i915/display/intel_wm.h
> index e97cdca89a5c..f47e1354605d 100644
> --- a/drivers/gpu/drm/i915/display/intel_wm.h
> +++ b/drivers/gpu/drm/i915/display/intel_wm.h
> @@ -31,5 +31,7 @@ void intel_print_wm_latency(struct drm_i915_private *i915,
> const char *name, const u16 wm[]);
> void intel_wm_init(struct drm_i915_private *i915);
> void intel_wm_debugfs_register(struct drm_i915_private *i915);
> +void intel_program_dpkgc_latency(struct intel_atomic_state *state,
> + struct drm_i915_private *i915);
>
> #endif /* __INTEL_WM_H__ */
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c
> b/drivers/gpu/drm/i915/display/skl_watermark.c
> index 1a4c1fa24820..d419edb196c6 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -28,12 +28,6 @@
> #include "skl_watermark.h"
> #include "skl_watermark_regs.h"
>
> -/*It is expected that DSB can do posted writes to every register in
> - * the pipe and planes within 100us. For flip queue use case, the
> - * recommended DSB execution time is 100us + one SAGV block time.
> - */
> -#define DSB_EXE_TIME 100
> -
> static void skl_sagv_disable(struct drm_i915_private *i915);
>
> /* Stores plane specific WM parameters */
> @@ -2844,51 +2838,12 @@ static int skl_wm_add_affected_planes(struct intel_atomic_state *state,
> return 0;
> }
>
> -/*
> - * If Fixed Refresh Rate or For VRR case Vmin = Vmax = Flipline:
> - * Program DEEP PKG_C_LATENCY Pkg C with highest valid latency from
> - * watermark level1 and up and above. If watermark level 1 is
> - * invalid program it with all 1's.
> - * Program PKG_C_LATENCY Added Wake Time = DSB execution time
> - * If Variable Refresh Rate where Vmin != Vmax != Flipline:
> - * Program DEEP PKG_C_LATENCY Pkg C with all 1's.
> - * Program PKG_C_LATENCY Added Wake Time = 0
> - */
> -static void
> -skl_program_dpkgc_latency(struct drm_i915_private *i915, bool enable_dpkgc)
> -{
> - u32 max_latency = 0;
> - u32 clear = 0, val = 0;
> - u32 added_wake_time = 0;
> -
> - if (DISPLAY_VER(i915) < 20)
> - return;
> -
> - if (enable_dpkgc) {
> - max_latency = skl_watermark_max_latency(i915, 1);
> - if (max_latency == 0)
> - max_latency = LNL_PKG_C_LATENCY_MASK;
> - added_wake_time = DSB_EXE_TIME +
> - i915->display.sagv.block_time_us;
> - } else {
> - max_latency = LNL_PKG_C_LATENCY_MASK;
> - added_wake_time = 0;
> - }
> -
> - clear |= LNL_ADDED_WAKE_TIME_MASK | LNL_PKG_C_LATENCY_MASK;
> - val |= REG_FIELD_PREP(LNL_PKG_C_LATENCY_MASK, max_latency);
> - val |= REG_FIELD_PREP(LNL_ADDED_WAKE_TIME_MASK, added_wake_time);
> -
> - intel_uncore_rmw(&i915->uncore, LNL_PKG_C_LATENCY, clear, val);
> -}
> -
> static int
> skl_compute_wm(struct intel_atomic_state *state)
> {
> struct intel_crtc *crtc;
> struct intel_crtc_state __maybe_unused *new_crtc_state;
> int ret, i;
> - bool enable_dpkgc = false;
>
> for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
> ret = skl_build_pipe_wm(state, crtc);
> @@ -2913,15 +2868,8 @@ skl_compute_wm(struct intel_atomic_state *state)
> ret = skl_wm_add_affected_planes(state, crtc);
> if (ret)
> return ret;
> -
> - if ((new_crtc_state->vrr.vmin == new_crtc_state->vrr.vmax &&
> - new_crtc_state->vrr.vmin == new_crtc_state->vrr.flipline) ||
> - !new_crtc_state->vrr.enable)
> - enable_dpkgc = true;
> }
>
> - skl_program_dpkgc_latency(to_i915(state->base.dev), enable_dpkgc);
> -
> skl_print_wm_changes(state);
>
> return 0;
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