Hi Jacopo,
Thank you for the patch.
On Sun, Aug 25, 2019 at 03:51:48PM +0200, Jacopo Mondi wrote:
Add a driver for the R-Car Display Unit Color Correction Module.
In most of Gen3 SoCs, each DU output channel is provided with a CMM unit to perform image enhancement and color correction.
Add support for CMM through a driver that supports configuration of the 1-dimensional LUT table. More advanced CMM feature will be implemented on top of this basic one.
Signed-off-by: Jacopo Mondi jacopo+renesas@jmondi.org
drivers/gpu/drm/rcar-du/Kconfig | 7 + drivers/gpu/drm/rcar-du/Makefile | 1 + drivers/gpu/drm/rcar-du/rcar_cmm.c | 262 +++++++++++++++++++++++++++++ drivers/gpu/drm/rcar-du/rcar_cmm.h | 38 +++++ 4 files changed, 308 insertions(+) create mode 100644 drivers/gpu/drm/rcar-du/rcar_cmm.c create mode 100644 drivers/gpu/drm/rcar-du/rcar_cmm.h
diff --git a/drivers/gpu/drm/rcar-du/Kconfig b/drivers/gpu/drm/rcar-du/Kconfig index 1529849e217e..539d232790d1 100644 --- a/drivers/gpu/drm/rcar-du/Kconfig +++ b/drivers/gpu/drm/rcar-du/Kconfig @@ -13,6 +13,13 @@ config DRM_RCAR_DU Choose this option if you have an R-Car chipset. If M is selected the module will be called rcar-du-drm.
+config DRM_RCAR_CMM
- bool "R-Car DU Color Management Module (CMM) Support"
- depends on DRM && OF
- depends on DRM_RCAR_DU
- help
Enable support for R-Car Color Management Module (CMM).config DRM_RCAR_DW_HDMI tristate "R-Car DU Gen3 HDMI Encoder Support" depends on DRM && OF diff --git a/drivers/gpu/drm/rcar-du/Makefile b/drivers/gpu/drm/rcar-du/Makefile index 6c2ed9c46467..4d1187ccc3e5 100644 --- a/drivers/gpu/drm/rcar-du/Makefile +++ b/drivers/gpu/drm/rcar-du/Makefile @@ -15,6 +15,7 @@ rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS) += rcar_du_of.o \ rcar-du-drm-$(CONFIG_DRM_RCAR_VSP) += rcar_du_vsp.o rcar-du-drm-$(CONFIG_DRM_RCAR_WRITEBACK) += rcar_du_writeback.o
+obj-$(CONFIG_DRM_RCAR_CMM) += rcar_cmm.o obj-$(CONFIG_DRM_RCAR_DU) += rcar-du-drm.o obj-$(CONFIG_DRM_RCAR_DW_HDMI) += rcar_dw_hdmi.o obj-$(CONFIG_DRM_RCAR_LVDS) += rcar_lvds.o diff --git a/drivers/gpu/drm/rcar-du/rcar_cmm.c b/drivers/gpu/drm/rcar-du/rcar_cmm.c new file mode 100644 index 000000000000..55361f5701e8 --- /dev/null +++ b/drivers/gpu/drm/rcar-du/rcar_cmm.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- rcar_cmm.c -- R-Car Display Unit Color Management Module
- Copyright (C) 2019 Jacopo Mondi jacopo+renesas@jmondi.org
- */
+#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h>
+#include <drm/drm_color_mgmt.h>
+#include "rcar_cmm.h"
+#define CM2_LUT_CTRL 0x0000 +#define CM2_LUT_CTRL_LUT_EN BIT(0) +#define CM2_LUT_TBL_BASE 0x0600 +#define CM2_LUT_TBL(__i) (CM2_LUT_TBL_BASE + (__i) * 4)
+struct rcar_cmm {
- void __iomem *base;
- bool enabled;
- /*
* @lut: 1D-LUT status* @lut.enabled: 1D-LUT enabled flag* @lut.size: Number of entries in the LUT table
Please see my review of patch 13/14, I wonder if we could drop this field.
* @lut.table: Table of 1D-LUT entries scaled to HW support* precision (8-bits per color component)*/- struct {
bool enabled;unsigned int size;u32 table[CMM_GAMMA_LUT_SIZE];- } lut;
+};
+static inline int rcar_cmm_read(struct rcar_cmm *rcmm, u32 reg) +{
- return ioread32(rcmm->base + reg);
+}
+static inline void rcar_cmm_write(struct rcar_cmm *rcmm, u32 reg, u32 data) +{
- iowrite32(data, rcmm->base + reg);
+}
+/*
- rcar_cmm_lut_extract() - Scale down to hw precision the DRM LUT table
s/hw/hardware/ (and below too)
entries and store them.
- @rcmm: Pointer to the CMM device
- @size: Number of entries in the table
- @drm_lut: DRM LUT table
- */
+static void rcar_cmm_lut_extract(struct rcar_cmm *rcmm, size_t size,
const struct drm_color_lut *drm_lut)+{
- unsigned int i;
- for (i = 0; i < size; ++i) {
const struct drm_color_lut *lut = &drm_lut[i];rcmm->lut.table[i] = drm_color_lut_extract(lut->red, 8) << 16| drm_color_lut_extract(lut->green, 8) << 8| drm_color_lut_extract(lut->blue, 8);- }
- rcmm->lut.size = size;
+}
+/*
- rcar_cmm_lut_load() - Write to hw the LUT table entries from the local table.
No need for a blank line
- @rcmm: Pointer to the CMM device
- */
+static void rcar_cmm_lut_load(struct rcar_cmm *rcmm)
I would name this rcar_cmm_lut_write().
+{
- unsigned int i;
- for (i = 0; i < rcmm->lut.size; ++i) {
u32 entry = rcmm->lut.table[i];rcar_cmm_write(rcmm, CM2_LUT_TBL(i), entry);
You don't need the local entry variable.
- }
+}
+/**
- rcar_cmm_setup() - configure the CMM unit
s/configure/Configure/ and s/$/./, or the other way around for the other functions (I don't mine which one, but let's stay consistent).
No need for a blank line (same for the functions below).
- @pdev: The platform device associated with the CMM instance
- @config: The CRTC-provided configuration.
- Configure the CMM unit with the CRTC-provided configuration.
- Currently enabling, disabling and programming of the 1-D LUT unit is
- supported.
- */
+int rcar_cmm_setup(struct platform_device *pdev,
const struct rcar_cmm_config *config)+{
- struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
- if (config->lut.size > CMM_GAMMA_LUT_SIZE)
return -EINVAL;- /*
* As rcar_cmm_setup() is called by atomic commit tail helper, it might* be called when the CMM is disabled. As we can't program the hardware* in that case, store the configuration internally and apply it when* the CMM will be enabled by the CRTC through rcar_cmm_enable().*/- if (!rcmm->enabled) {
if (!config->lut.enable)return 0;rcar_cmm_lut_extract(rcmm, config->lut.size, config->lut.table);rcmm->lut.enabled = true;return 0;- }
- /* Stop LUT operations if requested. */
- if (!config->lut.enable) {
if (rcmm->lut.enabled) {rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0);rcmm->lut.enabled = false;rcmm->lut.size = 0;}return 0;- }
- /*
* Enable LUT and program the new gamma table values.** FIXME: In order to have stable operations it is required to first* enable the 1D-LUT and then program its table entries. This seems to* contradict what the chip manual reports, and will have to be* reconsidered when implementing support for double buffering.*/- if (!rcmm->lut.enabled) {
rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_LUT_EN);rcmm->lut.enabled = true;- }
- rcar_cmm_lut_extract(rcmm, config->lut.size, config->lut.table);
- rcar_cmm_lut_load(rcmm);
- return 0;
+} +EXPORT_SYMBOL_GPL(rcar_cmm_setup);
+/**
- rcar_cmm_enable() - enable the CMM unit
- @pdev: The platform device associated with the CMM instance
- Enable the CMM unit by enabling the parent clock and enabling the CMM
- components, such as 1-D LUT, if requested.
- */
+int rcar_cmm_enable(struct platform_device *pdev) +{
- struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
- int ret;
- if (!rcmm)
return -EPROBE_DEFER;
This function is called in rcar_du_crtc_atomic_enable(), so that's not the right error code. It seems we need another function for the CMM API to defer probing :-/ I would call it rcar_cmm_init(). This check would then be removed.
- ret = pm_runtime_get_sync(&pdev->dev);
- if (ret < 0)
return ret;- /* Apply the LUT table values saved at rcar_cmm_setup() time. */
- if (rcmm->lut.enabled) {
rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_LUT_EN);rcar_cmm_lut_load(rcmm);
You will not like this, but I just realised that we're now reprogramming the LUT contents every time the CMM is enabled. Do you think that's something we should optimise ? And yes, that would require introducing back an update flag in rcmm->lut :-S Sorry for not realising this when I proposed dropping it.
- }
- rcmm->enabled = true;
- return 0;
+} +EXPORT_SYMBOL_GPL(rcar_cmm_enable);
+/**
- rcar_cmm_disable() - disable the CMM unit
- @pdev: The platform device associated with the CMM instance
- Disable the CMM unit by stopping the parent clock.
- */
+void rcar_cmm_disable(struct platform_device *pdev) +{
- struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
- rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0);
- pm_runtime_put(&pdev->dev);
- rcmm->lut.enabled = false;
- rcmm->lut.size = 0;
- rcmm->enabled = false;
+} +EXPORT_SYMBOL_GPL(rcar_cmm_disable);
+static int rcar_cmm_probe(struct platform_device *pdev) +{
- struct rcar_cmm *rcmm;
- struct resource *res;
- rcmm = devm_kzalloc(&pdev->dev, sizeof(*rcmm), GFP_KERNEL);
- if (!rcmm)
return -ENOMEM;- platform_set_drvdata(pdev, rcmm);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- rcmm->base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(rcmm->base))
return PTR_ERR(rcmm->base);
You really don't like combining those two calls, do you ? :-)
- pm_runtime_enable(&pdev->dev);
- return 0;
+}
+static int rcar_cmm_remove(struct platform_device *pdev) +{
- pm_runtime_disable(&pdev->dev);
- return 0;
+}
+static const struct of_device_id rcar_cmm_of_table[] = {
- { .compatible = "renesas,cmm-r8a7795", },
- { .compatible = "renesas,cmm-r8a7796", },
- { .compatible = "renesas,cmm-r8a77965", },
- { .compatible = "renesas,cmm-r8a77990", },
- { .compatible = "renesas,cmm-r8a77995", },
As Geert pointed out, I would drop those entries.
- { .compatible = "renesas,rcar-gen3-cmm", },
- { .compatible = "renesas,rcar-gen2-cmm", },
- { },
+}; +MODULE_DEVICE_TABLE(of, rcar_cmm_of_table);
+static struct platform_driver rcar_cmm_platform_driver = {
- .probe = rcar_cmm_probe,
- .remove = rcar_cmm_remove,
- .driver = {
.name = "rcar-cmm",.of_match_table = rcar_cmm_of_table,- },
+};
+module_platform_driver(rcar_cmm_platform_driver);
+MODULE_AUTHOR("Jacopo Mondi jacopo+renesas@jmondi.org"); +MODULE_DESCRIPTION("Renesas R-Car CMM Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/rcar-du/rcar_cmm.h b/drivers/gpu/drm/rcar-du/rcar_cmm.h new file mode 100644 index 000000000000..b0bb7349ebaa --- /dev/null +++ b/drivers/gpu/drm/rcar-du/rcar_cmm.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*
- rcar_cmm.h -- R-Car Display Unit Color Management Module
- Copyright (C) 2019 Jacopo Mondi jacopo+renesas@jmondi.org
- */
+#ifndef __RCAR_CMM_H__ +#define __RCAR_CMM_H__
+#define CMM_GAMMA_LUT_SIZE 256
+struct drm_color_lut; +struct platform_device;
+/**
- struct rcar_cmm_config - CMM configuration
- @lut: 1D-LUT configuration
- @lut.enable: 1D-LUT enable flag
- @lut.table: 1D-LUT table entries
- @lut.size: Number of 1D-LUT (max 256)
s/1D-LUT/1D-LUT entries/
- */
+struct rcar_cmm_config {
- struct {
bool enable;struct drm_color_lut *table;unsigned int size;- } lut;
+};
+int rcar_cmm_enable(struct platform_device *pdev); +void rcar_cmm_disable(struct platform_device *pdev);
+int rcar_cmm_setup(struct platform_device *pdev,
const struct rcar_cmm_config *config);+#endif /* __RCAR_CMM_H__ */