On Tue, Oct 08, 2019 at 08:00:37PM -0300, Ezequiel Garcia wrote:
> Add an optional CRTC gamma LUT support, and enable it on RK3288.
> This is currently enabled via a separate address resource,
> which needs to be specified in the devicetree.
>
> The address resource is required because on some SoCs, such as
> RK3288, the LUT address is after the MMU address, and the latter
> is supported by a different driver. This prevents the DRM driver
> from requesting an entire register space.
>
> The current implementation works for RGB 10-bit tables, as that
> is what seems to work on RK3288.
>
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
Hey Ezequiel,
Just a few comments on the actual content of the patch as opposed to my higher
level comments yesterday. I think we're almost there, thanks for sticking this
out!
> ---
> Changes from v3:
> * Move to atomic_enable and atomic_begin,
> as discussed with Sean Paul.
> * Dropped the Reviewed-bys.
> Changes from v2:
> * None.
> Changes from v1:
> * drop explicit linear LUT after finding a proper
> way to disable gamma correction.
> * avoid setting gamma is the CRTC is not active.
> * s/int/unsigned int as suggested by Jacopo.
> * only enable color management and set gamma size
> if gamma LUT is supported, suggested by Doug.
> * drop the reg-names usage, and instead just use indexed reg
> specifiers, suggested by Doug.
> Changes from RFC:
> * Request (an optional) address resource for the LUT.
> * Drop support for RK3399, which doesn't seem to work
> out of the box and needs more research.
> * Support pass-thru setting when GAMMA_LUT is NULL.
> * Add a check for the gamma size, as suggested by Ilia.
> * Move gamma setting to atomic_commit_tail, as pointed
> out by Jacopo/Laurent, is the correct way.
> ---
> drivers/gpu/drm/rockchip/rockchip_drm_fb.c | 1 +
> drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 125 ++++++++++++++++++++
> drivers/gpu/drm/rockchip/rockchip_drm_vop.h | 5 +
> drivers/gpu/drm/rockchip/rockchip_vop_reg.c | 2 +
> 4 files changed, 133 insertions(+)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
> index ca01234c037c..697ee04b85cf 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
> @@ -17,6 +17,7 @@
> #include "rockchip_drm_drv.h"
> #include "rockchip_drm_fb.h"
> #include "rockchip_drm_gem.h"
> +#include "rockchip_drm_vop.h"
Leftover from the previous version?
>
> static const struct drm_framebuffer_funcs rockchip_drm_fb_funcs = {
> .destroy = drm_gem_fb_destroy,
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
> index 613404f86668..85c1269a1218 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
> @@ -139,6 +139,7 @@ struct vop {
>
> uint32_t *regsbak;
> void __iomem *regs;
> + void __iomem *lut_regs;
>
> /* physical map length of vop register */
> uint32_t len;
> @@ -1048,6 +1049,84 @@ static bool vop_crtc_mode_fixup(struct drm_crtc *crtc,
> return true;
> }
>
> +static bool vop_dsp_lut_is_enable(struct vop *vop)
*enabled
> +{
> + return vop_read_reg(vop, 0, &vop->data->common->dsp_lut_en);
> +}
> +
> +static void vop_crtc_write_gamma_lut(struct vop *vop, struct drm_crtc *crtc)
> +{
> + struct drm_color_lut *lut = crtc->state->gamma_lut->data;
> + unsigned int i;
> +
> + for (i = 0; i < crtc->gamma_size; i++) {
> + u32 word;
> +
> + word = (drm_color_lut_extract(lut[i].red, 10) << 20) |
> + (drm_color_lut_extract(lut[i].green, 10) << 10) |
> + drm_color_lut_extract(lut[i].blue, 10);
> + writel(word, vop->lut_regs + i * 4);
> + }
> +}
> +
> +static void vop_crtc_gamma_set(struct vop *vop, struct drm_crtc *crtc,
> + struct drm_crtc_state *old_crtc_state)
> +{
> + unsigned int idle;
> + int ret;
> +
How about:
if (!vop->lut_regs)
return;
here and then you can remove that condition above the 2 callsites
> + /*
> + * In order to write the LUT to the internal memory,
> + * we need to first make sure the dsp_lut_en bit is cleared.
> + */
> + spin_lock(&vop->reg_lock);
> + VOP_REG_SET(vop, common, dsp_lut_en, 0);
> + vop_cfg_done(vop);
> + spin_unlock(&vop->reg_lock);
> +
> + /*
> + * If the CRTC is not active, dsp_lut_en will not get cleared.
> + * Apparently we still need to do the above step to for
> + * gamma correction to be disabled.
> + */
> + if (!crtc->state->active)
> + return;
> +
> + ret = readx_poll_timeout(vop_dsp_lut_is_enable, vop,
> + idle, !idle, 5, 30 * 1000);
> + if (ret) {
> + DRM_DEV_ERROR(vop->dev, "display LUT RAM enable timeout!\n");
> + return;
> + }
> +
> + if (crtc->state->gamma_lut &&
> + (!old_crtc_state->gamma_lut || (crtc->state->gamma_lut->base.id !=
> + old_crtc_state->gamma_lut->base.id))) {
Silly question, but isn't the second part of this check redundant since you need
color_mgmt_changed || active_changed to get into this function?
So maybe invert the conditional here and exit early (to save a level of
indentation in the block below):
if (!crtc->state->gamma_lut)
return;
spin_lock(&vop->reg_lock);
vop_crtc_write_gamma_lut(vop, crtc);
VOP_REG_SET(vop, common, dsp_lut_en, 1);
vop_cfg_done(vop);
spin_unlock(&vop->reg_lock);
> +
> + spin_lock(&vop->reg_lock);
> +
> + vop_crtc_write_gamma_lut(vop, crtc);
> + VOP_REG_SET(vop, common, dsp_lut_en, 1);
> + vop_cfg_done(vop);
> +
> + spin_unlock(&vop->reg_lock);
> + }
> +}
> +
> +static void vop_crtc_atomic_begin(struct drm_crtc *crtc,
> + struct drm_crtc_state *old_crtc_state)
> +{
> + struct vop *vop = to_vop(crtc);
> +
> + /*
> + * Only update GAMMA if the 'active' flag is not changed,
> + * otherwise it's updated by .atomic_enable.
> + */
> + if (vop->lut_regs && crtc->state->color_mgmt_changed &&
> + !crtc->state->active_changed)
> + vop_crtc_gamma_set(vop, crtc, old_crtc_state);
> +}
> +
> static void vop_crtc_atomic_enable(struct drm_crtc *crtc,
> struct drm_crtc_state *old_state)
> {
> @@ -1075,6 +1154,14 @@ static void vop_crtc_atomic_enable(struct drm_crtc *crtc,
> return;
> }
>
> + /*
> + * If we have a GAMMA LUT in the state, then let's make sure
> + * it's updated. We might be coming out of suspend,
> + * which means the LUT internal memory needs to be re-written.
> + */
> + if (vop->lut_regs && crtc->state->gamma_lut)
> + vop_crtc_gamma_set(vop, crtc, old_state);
> +
> mutex_lock(&vop->vop_lock);
>
> WARN_ON(vop->event);
> @@ -1191,6 +1278,26 @@ static void vop_wait_for_irq_handler(struct vop *vop)
> synchronize_irq(vop->irq);
> }
>
> +static int vop_crtc_atomic_check(struct drm_crtc *crtc,
> + struct drm_crtc_state *crtc_state)
> +{
> + struct vop *vop = to_vop(crtc);
> +
> + if (vop->lut_regs && crtc_state->color_mgmt_changed &&
> + crtc_state->gamma_lut) {
> + unsigned int len;
> +
> + len = drm_color_lut_size(crtc_state->gamma_lut);
> + if (len != crtc->gamma_size) {
> + DRM_DEBUG_KMS("Invalid LUT size; got %d, expected %d\n",
> + len, crtc->gamma_size);
> + return -EINVAL;
> + }
Overflow is avoided in drm_mode_gamma_set_ioctl(), so I don't think you need
this function.
Sean
> + }
> +
> + return 0;
> +}
> +
> static void vop_crtc_atomic_flush(struct drm_crtc *crtc,
> struct drm_crtc_state *old_crtc_state)
> {
> @@ -1243,6 +1350,8 @@ static void vop_crtc_atomic_flush(struct drm_crtc *crtc,
>
> static const struct drm_crtc_helper_funcs vop_crtc_helper_funcs = {
> .mode_fixup = vop_crtc_mode_fixup,
> + .atomic_check = vop_crtc_atomic_check,
> + .atomic_begin = vop_crtc_atomic_begin,
> .atomic_flush = vop_crtc_atomic_flush,
> .atomic_enable = vop_crtc_atomic_enable,
> .atomic_disable = vop_crtc_atomic_disable,
> @@ -1361,6 +1470,7 @@ static const struct drm_crtc_funcs vop_crtc_funcs = {
> .disable_vblank = vop_crtc_disable_vblank,
> .set_crc_source = vop_crtc_set_crc_source,
> .verify_crc_source = vop_crtc_verify_crc_source,
> + .gamma_set = drm_atomic_helper_legacy_gamma_set,
> };
>
> static void vop_fb_unref_worker(struct drm_flip_work *work, void *val)
> @@ -1518,6 +1628,10 @@ static int vop_create_crtc(struct vop *vop)
> goto err_cleanup_planes;
>
> drm_crtc_helper_add(crtc, &vop_crtc_helper_funcs);
> + if (vop->lut_regs) {
> + drm_mode_crtc_set_gamma_size(crtc, vop_data->lut_size);
> + drm_crtc_enable_color_mgmt(crtc, 0, false, vop_data->lut_size);
> + }
>
> /*
> * Create drm_planes for overlay windows with possible_crtcs restricted
> @@ -1822,6 +1936,17 @@ static int vop_bind(struct device *dev, struct device *master, void *data)
> if (IS_ERR(vop->regs))
> return PTR_ERR(vop->regs);
>
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + if (res) {
> + if (!vop_data->lut_size) {
> + DRM_DEV_ERROR(dev, "no gamma LUT size defined\n");
> + return -EINVAL;
> + }
> + vop->lut_regs = devm_ioremap_resource(dev, res);
> + if (IS_ERR(vop->lut_regs))
> + return PTR_ERR(vop->lut_regs);
> + }
> +
> vop->regsbak = devm_kzalloc(dev, vop->len, GFP_KERNEL);
> if (!vop->regsbak)
> return -ENOMEM;
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
> index 2149a889c29d..8192c90d48c4 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
> @@ -7,6 +7,8 @@
> #ifndef _ROCKCHIP_DRM_VOP_H
> #define _ROCKCHIP_DRM_VOP_H
>
> +#include <drm/drm_atomic.h>
> +
> /*
> * major: IP major version, used for IP structure
> * minor: big feature change under same structure
> @@ -67,6 +69,7 @@ struct vop_common {
> struct vop_reg dither_down_mode;
> struct vop_reg dither_down_en;
> struct vop_reg dither_up;
> + struct vop_reg dsp_lut_en;
> struct vop_reg gate_en;
> struct vop_reg mmu_en;
> struct vop_reg out_mode;
> @@ -170,6 +173,7 @@ struct vop_data {
> const struct vop_win_yuv2yuv_data *win_yuv2yuv;
> const struct vop_win_data *win;
> unsigned int win_size;
> + unsigned int lut_size;
>
> #define VOP_FEATURE_OUTPUT_RGB10 BIT(0)
> #define VOP_FEATURE_INTERNAL_RGB BIT(1)
> @@ -373,4 +377,5 @@ static inline int scl_vop_cal_lb_mode(int width, bool is_yuv)
> }
>
> extern const struct component_ops vop_component_ops;
> +
> #endif /* _ROCKCHIP_DRM_VOP_H */
> diff --git a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
> index d1494be14471..42ddcb698c82 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
> @@ -598,6 +598,7 @@ static const struct vop_common rk3288_common = {
> .dither_down_en = VOP_REG(RK3288_DSP_CTRL1, 0x1, 2),
> .pre_dither_down = VOP_REG(RK3288_DSP_CTRL1, 0x1, 1),
> .dither_up = VOP_REG(RK3288_DSP_CTRL1, 0x1, 6),
> + .dsp_lut_en = VOP_REG(RK3288_DSP_CTRL1, 0x1, 0),
> .data_blank = VOP_REG(RK3288_DSP_CTRL0, 0x1, 19),
> .dsp_blank = VOP_REG(RK3288_DSP_CTRL0, 0x3, 18),
> .out_mode = VOP_REG(RK3288_DSP_CTRL0, 0xf, 0),
> @@ -646,6 +647,7 @@ static const struct vop_data rk3288_vop = {
> .output = &rk3288_output,
> .win = rk3288_vop_win_data,
> .win_size = ARRAY_SIZE(rk3288_vop_win_data),
> + .lut_size = 1024,
> };
>
> static const int rk3368_vop_intrs[] = {
> --
> 2.22.0
>
--
Sean Paul, Software Engineer, Google / Chromium OS
