Re: [PATCH] drm: mali-dp: Add CTM support
From: Brian Starkey
Date: Wed Feb 01 2017 - 08:46:46 EST
+Daniel to weigh in on the coefficient conversion.
On Wed, Feb 01, 2017 at 12:05:03PM +0000, Mihail Atanassov wrote:
All DPs have a COLORADJ matrix which is applied prior to output gamma.
Attach that to the CTM property. Also, ensure the input CTM's coefficients
can fit in the DP registers' Q3.12 format.
Signed-off-by: Mihail Atanassov <mihail.atanassov@xxxxxxx>
---
This patch depends on "[PATCH 2/2] drm: mali-dp: enable gamma support", sent
out earlier (https://lkml.org/lkml/2017/2/1/201).
drivers/gpu/drm/arm/malidp_crtc.c | 59 +++++++++++++++++++++++++++++++++++++--
drivers/gpu/drm/arm/malidp_drv.c | 35 +++++++++++++++++++++++
drivers/gpu/drm/arm/malidp_drv.h | 1 +
drivers/gpu/drm/arm/malidp_regs.h | 2 ++
4 files changed, 95 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/arm/malidp_crtc.c b/drivers/gpu/drm/arm/malidp_crtc.c
index 10f79b6..2f366e4 100644
--- a/drivers/gpu/drm/arm/malidp_crtc.c
+++ b/drivers/gpu/drm/arm/malidp_crtc.c
@@ -190,6 +190,55 @@ static int malidp_crtc_atomic_check_gamma(struct drm_crtc *crtc,
return 0;
}
+/*
+ * Check if there is a new CTM and if it contains valid input. Valid here means
+ * that the number is inside the representable range for a Q3.12 number,
+ * excluding truncating the fractional part of the input data.
+ *
+ * The COLORADJ registers can be changed atomically.
+ */
+static int malidp_crtc_atomic_check_ctm(struct drm_crtc *crtc,
+ struct drm_crtc_state *state)
+{
+ struct malidp_crtc_state *mc = to_malidp_crtc_state(state);
+ struct drm_color_ctm *ctm;
+ int i;
+
+ if (!state->color_mgmt_changed)
+ return 0;
+
+ if (!state->ctm)
+ return 0;
+
+ if (crtc->state->ctm && (crtc->state->ctm->base.id ==
+ state->ctm->base.id))
+ return 0;
+
+ /*
+ * The size of the ctm is checked in
+ * drm_atomic_replace_property_blob_from_id.
+ */
+ ctm = (struct drm_color_ctm *)state->ctm->data;
+ for (i = 0; i < ARRAY_SIZE(ctm->matrix); ++i) {
+ /* Convert from S31.32 to Q3.12. */
+ s64 val = ctm->matrix[i];
+ u64 mag = ((((u64)val) & ~BIT_ULL(63)) >> 20) &
+ GENMASK_ULL(14, 0);
nitpick: You don't need 64 bits for mag.
Daniel was suggesting implementing a helper to change the S31.32 into
something more useful (presumably Q32.32), as probably the
sign+magnitude format isn't really useful to most drivers.
I'm not sure what he had in mind exactly; whether we should convert
the whole matrix up-front into a new copy, or just provide a helper
for drivers to use when reading the matrix.
+
+ /* Check the destination's top bit for overflow. */
... and also convert to two's complement.
For the overflow check though I think it would be more obvious to look
at bit 34 in the original S31.32 value (or bit 14 before you mask it).
There's no trickiness around inverting then.
-Brian
+ if (val & BIT_ULL(63)) {
+ mag = ~mag + 1;
+ if (!(mag & BIT_ULL(14)))
+ return -EINVAL;
+ } else if (mag & BIT_ULL(14)) {
+ return -EINVAL;
+ }
+ mc->coloradj_coeffs[i] = mag;
+ }
+
+ return 0;
+}
+
static int malidp_crtc_atomic_check(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
@@ -270,6 +319,10 @@ static int malidp_crtc_atomic_check(struct drm_crtc *crtc,
if (ret)
return ret;
+ ret = malidp_crtc_atomic_check_ctm(crtc, state);
+ if (ret)
+ return ret;
+
return 0;
}
@@ -289,6 +342,8 @@ static struct drm_crtc_state *malidp_crtc_duplicate_state(struct drm_crtc *crtc)
__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
memcpy(state->gamma_coeffs, cs->gamma_coeffs,
sizeof(state->gamma_coeffs));
+ memcpy(state->coloradj_coeffs, cs->coloradj_coeffs,
+ sizeof(state->coloradj_coeffs));
return &state->base;
}
@@ -359,10 +414,10 @@ int malidp_crtc_init(struct drm_device *drm)
drm_crtc_helper_add(&malidp->crtc, &malidp_crtc_helper_funcs);
drm_mode_crtc_set_gamma_size(&malidp->crtc, 4096);
- /* No inverse-gamma and color adjustments yet. */
+ /* No inverse-gamma: it is per-plane. */
drm_crtc_enable_color_mgmt(&malidp->crtc,
0,
- false,
+ true,
4096);
return 0;
diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index a9f787d..682901a 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -78,6 +78,37 @@ static void malidp_atomic_commit_update_gamma(struct drm_crtc *crtc,
}
}
+static
+void malidp_atomic_commit_update_coloradj(struct drm_crtc *crtc,
+ struct drm_crtc_state *old_state)
+{
+ struct malidp_drm *malidp = crtc_to_malidp_device(crtc);
+ struct malidp_hw_device *hwdev = malidp->dev;
+ int i;
+
+ if (!crtc->state->color_mgmt_changed)
+ return;
+
+ if (!crtc->state->ctm) {
+ malidp_hw_clearbits(hwdev, MALIDP_DISP_FUNC_CADJ,
+ MALIDP_DE_DISPLAY_FUNC);
+ } else {
+ struct malidp_crtc_state *mc =
+ to_malidp_crtc_state(crtc->state);
+
+ if (!old_state->ctm || (crtc->state->ctm->base.id !=
+ old_state->ctm->base.id))
+ for (i = 0; i < MALIDP_COLORADJ_NUM_COEFFS; ++i)
+ malidp_hw_write(hwdev,
+ mc->coloradj_coeffs[i],
+ hwdev->map.coeffs_base +
+ MALIDP_COLOR_ADJ_COEF + 4 * i);
+
+ malidp_hw_setbits(hwdev, MALIDP_DISP_FUNC_CADJ,
+ MALIDP_DE_DISPLAY_FUNC);
+ }
+}
+
/*
* set the "config valid" bit and wait until the hardware acts on it
*/
@@ -144,6 +175,10 @@ static void malidp_atomic_commit_tail(struct drm_atomic_state *state)
malidp_atomic_commit_update_gamma(crtc, old_crtc_state);
drm_atomic_helper_commit_modeset_enables(drm, state);
+
+ for_each_crtc_in_state(state, crtc, old_crtc_state, i)
+ malidp_atomic_commit_update_coloradj(crtc, old_crtc_state);
+
drm_atomic_helper_commit_planes(drm, state, 0);
malidp_atomic_commit_hw_done(state);
diff --git a/drivers/gpu/drm/arm/malidp_drv.h b/drivers/gpu/drm/arm/malidp_drv.h
index 374d43e..55b0f8b 100644
--- a/drivers/gpu/drm/arm/malidp_drv.h
+++ b/drivers/gpu/drm/arm/malidp_drv.h
@@ -50,6 +50,7 @@ struct malidp_plane_state {
struct malidp_crtc_state {
struct drm_crtc_state base;
u32 gamma_coeffs[MALIDP_COEFFTAB_NUM_COEFFS];
+ u32 coloradj_coeffs[MALIDP_COLORADJ_NUM_COEFFS];
};
#define to_malidp_crtc_state(x) container_of(x, struct malidp_crtc_state, base)
diff --git a/drivers/gpu/drm/arm/malidp_regs.h b/drivers/gpu/drm/arm/malidp_regs.h
index 2e213c3..b15ef50 100644
--- a/drivers/gpu/drm/arm/malidp_regs.h
+++ b/drivers/gpu/drm/arm/malidp_regs.h
@@ -64,6 +64,7 @@
/* bit masks that are common between products */
#define MALIDP_CFG_VALID (1 << 0)
#define MALIDP_DISP_FUNC_GAM (1 << 0)
+#define MALIDP_DISP_FUNC_CADJ (1 << 4)
#define MALIDP_DISP_FUNC_ILACED (1 << 8)
/* register offsets for IRQ management */
@@ -93,6 +94,7 @@
#define MALIDP_DE_H_ACTIVE(x) (((x) & 0x1fff) << 0)
#define MALIDP_DE_V_ACTIVE(x) (((x) & 0x1fff) << 16)
+#define MALIDP_COLORADJ_NUM_COEFFS 12
#define MALIDP_COEFFTAB_NUM_COEFFS 64
/* register offsets relative to MALIDP5x0_COEFFS_BASE */
#define MALIDP_COLOR_ADJ_COEF 0x00000
--
1.9.1