register
The strength value for sharpness is based on user input and
the winsize is based on resolution. Set the casf_enable flag
if there is a platform support and uapi strength is not zero.
Once the sharpness is enabled then just update the strength
bit of the register everytime whenever user changes the strength
as enable bit and winsize bit remains constant.
v2: Introduce get_config for casf[Ankit]
Signed-off-by: Nemesa Garg <nemesa.garg@xxxxxxxxx>
---
drivers/gpu/drm/i915/Makefile | 1 +
drivers/gpu/drm/i915/display/intel_casf.c | 99 +++++++++++++++++++
drivers/gpu/drm/i915/display/intel_casf.h | 17 ++++
.../gpu/drm/i915/display/intel_casf_regs.h | 22 +++++
.../drm/i915/display/intel_crtc_state_dump.c | 7 ++
.../drm/i915/display/intel_display_types.h | 7 ++
drivers/gpu/drm/i915/display/skl_scaler.c | 1 +
drivers/gpu/drm/xe/Makefile | 1 +
8 files changed, 155 insertions(+)
create mode 100644 drivers/gpu/drm/i915/display/intel_casf.c
create mode 100644 drivers/gpu/drm/i915/display/intel_casf.h
create mode 100644 drivers/gpu/drm/i915/display/intel_casf_regs.h
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index c8fc271b33b7..a955960d09ec 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -230,6 +230,7 @@ i915-y += \
display/intel_bios.o \
display/intel_bo.o \
display/intel_bw.o \
+ display/intel_casf.o \
display/intel_cdclk.o \
display/intel_cmtg.o \
display/intel_color.o \
diff --git a/drivers/gpu/drm/i915/display/intel_casf.c b/drivers/gpu/drm/i915/display/intel_casf.c
new file mode 100644
index 000000000000..28f76b06fd8f
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_casf.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2025 Intel Corporation
+ *
+ */
+#include "i915_reg.h"
+#include "intel_casf.h"
+#include "intel_casf_regs.h"
+#include "intel_de.h"
+#include "intel_display_types.h"
+
+#define MAX_PIXELS_FOR_3_TAP_FILTER (1920 * 1080)
+#define MAX_PIXELS_FOR_5_TAP_FILTER (3840 * 2160)
+
+/**
+ * DOC: Content Adaptive Sharpness Filter (CASF)
+ *
+ * From LNL onwards the display engine based adaptive
+ * sharpening filter is supported. This helps in
+ * improving the image quality. The display hardware
+ * uses one of the pipe scaler for implementing casf.
+ * It works on a region of pixels depending on the
+ * tap size. The coefficients are used to generate an
+ * alpha value which is used to blend the sharpened image
+ * to original image.
+ */
+
+void intel_casf_update_strength(struct intel_crtc_state *crtc_state)
+{
+ struct intel_display *display = to_intel_display(crtc_state);
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+
+ intel_de_rmw(display, SHARPNESS_CTL(crtc->pipe), 0,
+ FILTER_STRENGTH(crtc_state->hw.casf_params.strength));
+}
+
+static void intel_casf_compute_win_size(struct intel_crtc_state *crtc_state)
+{
+ const struct drm_display_mode *mode = &crtc_state->hw.adjusted_mode;
+ u16 total_pixels = mode->hdisplay * mode->vdisplay;
+
+ if (total_pixels <= MAX_PIXELS_FOR_3_TAP_FILTER)
+ crtc_state->hw.casf_params.win_size = SHARPNESS_FILTER_SIZE_3X3;
+ else if (total_pixels <= MAX_PIXELS_FOR_5_TAP_FILTER)
+ crtc_state->hw.casf_params.win_size = SHARPNESS_FILTER_SIZE_5X5;
+ else
+ crtc_state->hw.casf_params.win_size = SHARPNESS_FILTER_SIZE_7X7;
+}
+
+int intel_casf_compute_config(struct intel_crtc_state *crtc_state)
+{
+ struct intel_display *display = to_intel_display(crtc_state);
+
+ if (!HAS_CASF(display))
+ return 0;
+
+ if (crtc_state->uapi.sharpness_strength == 0) {
+ crtc_state->hw.casf_params.casf_enable = false;
+ crtc_state->hw.casf_params.strength = 0;
+ return 0;
+ }
+
+ crtc_state->hw.casf_params.casf_enable = true;
+
+ /*
+ * HW takes a value in form (1.0 + strength) in 4.4 fixed format.
+ * Strength is from 0.0-14.9375 ie from 0-239.
+ * User can give value from 0-255 but is clamped to 239.
+ * Ex. User gives 85 which is 5.3125 and adding 1.0 gives 6.3125.
+ * 6.3125 in 4.4 format is b01100101 which is equal to 101.
+ * Also 85 + 16 = 101.
+ */
+ crtc_state->hw.casf_params.strength =
+ min(crtc_state->uapi.sharpness_strength, 0xEF) + 0x10;
+
+ intel_casf_compute_win_size(crtc_state);
+
+ return 0;
+}
+
+void intel_casf_sharpness_get_config(struct intel_crtc_state *crtc_state)
+{
+ struct intel_display *display = to_intel_display(crtc_state);
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+ u32 sharp;
+
+ sharp = intel_de_read(display, SHARPNESS_CTL(crtc->pipe));
+ if (sharp & FILTER_EN) {
+ if (drm_WARN_ON(display->drm,
+ REG_FIELD_GET(FILTER_STRENGTH_MASK, sharp) < 16))
+ crtc_state->hw.casf_params.strength = 0;
+ else
+ crtc_state->hw.casf_params.strength =
+ REG_FIELD_GET(FILTER_STRENGTH_MASK, sharp);
+ crtc_state->hw.casf_params.casf_enable = true;
+ crtc_state->hw.casf_params.win_size =
+ REG_FIELD_GET(FILTER_SIZE_MASK, sharp);
+ }
+}
diff --git a/drivers/gpu/drm/i915/display/intel_casf.h b/drivers/gpu/drm/i915/display/intel_casf.h
new file mode 100644
index 000000000000..83523fe66c48
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_casf.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef __INTEL_CASF_H__
+#define __INTEL_CASF_H__
+
+#include <linux/types.h>
+
+struct intel_crtc_state;
+
+int intel_casf_compute_config(struct intel_crtc_state *crtc_state);
+void intel_casf_update_strength(struct intel_crtc_state *new_crtc_state);
+void intel_casf_sharpness_get_config(struct intel_crtc_state *crtc_state);
+
+#endif /* __INTEL_CASF_H__ */
diff --git a/drivers/gpu/drm/i915/display/intel_casf_regs.h b/drivers/gpu/drm/i915/display/intel_casf_regs.h
new file mode 100644
index 000000000000..c24ba281ae37
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_casf_regs.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2025 Intel Corporation
+ */
+
+#ifndef __INTEL_CASF_REGS_H__
+#define __INTEL_CASF_REGS_H__
+
+#include "intel_display_reg_defs.h"
+
+#define _SHARPNESS_CTL_A 0x682B0
+#define _SHARPNESS_CTL_B 0x68AB0
+#define SHARPNESS_CTL(pipe) _MMIO_PIPE(pipe, _SHARPNESS_CTL_A, _SHARPNESS_CTL_B)
+#define FILTER_EN REG_BIT(31)
+#define FILTER_STRENGTH_MASK REG_GENMASK(15, 8)
+#define FILTER_STRENGTH(x) REG_FIELD_PREP(FILTER_STRENGTH_MASK, (x))
+#define FILTER_SIZE_MASK REG_GENMASK(1, 0)
+#define SHARPNESS_FILTER_SIZE_3X3 REG_FIELD_PREP(FILTER_SIZE_MASK, 0)
+#define SHARPNESS_FILTER_SIZE_5X5 REG_FIELD_PREP(FILTER_SIZE_MASK, 1)
+#define SHARPNESS_FILTER_SIZE_7X7 REG_FIELD_PREP(FILTER_SIZE_MASK, 2)
+
+#endif /* __INTEL_CASF_REGS__ */
diff --git a/drivers/gpu/drm/i915/display/intel_crtc_state_dump.c b/drivers/gpu/drm/i915/display/intel_crtc_state_dump.c
index 599ddce96371..66b6fbae8294 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc_state_dump.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc_state_dump.c
@@ -372,6 +372,13 @@ void intel_crtc_state_dump(const struct intel_crtc_state *pipe_config,
intel_vdsc_state_dump(&p, 0, pipe_config);
+ if (HAS_CASF(i915)) {
+ drm_printf(&p, "sharpness strength: %d, sharpness tap size :%d\n sharpness enable :%d\n",
+ pipe_config->hw.casf_params.strength,
+ pipe_config->hw.casf_params.win_size,
+ pipe_config->hw.casf_params.casf_enable);
+ }
+
dump_planes:
if (!state)
return;
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 7d9cc430a6b8..2540a2a1a0e0 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -931,6 +931,12 @@ struct intel_csc_matrix {
u16 postoff[3];
};
+struct intel_casf {
+ u8 strength;
+ u8 win_size;
+ bool casf_enable;
+};
+
void intel_io_mmio_fw_write(void *ctx, i915_reg_t reg, u32 val);
typedef void (*intel_io_reg_write)(void *ctx, i915_reg_t reg, u32 val);
@@ -971,6 +977,7 @@ struct intel_crtc_state {
struct drm_property_blob *degamma_lut, *gamma_lut, *ctm;
struct drm_display_mode mode, pipe_mode, adjusted_mode;
enum drm_scaling_filter scaling_filter;
+ struct intel_casf casf_params;
} hw;
/* actual state of LUTs */
diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c
index ee81220a7c88..f0cf966211c9 100644
--- a/drivers/gpu/drm/i915/display/skl_scaler.c
+++ b/drivers/gpu/drm/i915/display/skl_scaler.c
@@ -5,6 +5,7 @@
#include "i915_drv.h"
#include "i915_reg.h"
+#include "intel_casf_regs.h"
#include "intel_de.h"
#include "intel_display_trace.h"
#include "intel_display_types.h"
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index cd464fe26eb8..785bda98973d 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -210,6 +210,7 @@ xe-$(CONFIG_DRM_XE_DISPLAY) += \
i915-display/intel_backlight.o \
i915-display/intel_bios.o \
i915-display/intel_bw.o \
+ i915-display/intel_casf.o \
i915-display/intel_cdclk.o \
i915-display/intel_cmtg.o \
i915-display/intel_color.o \
--
2.25.1
