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 | 292 +++++++++++++++++++++++++++++ drivers/gpu/drm/rcar-du/rcar_cmm.h | 38 ++++ 4 files changed, 338 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..76ed3fce2b33 --- /dev/null +++ b/drivers/gpu/drm/rcar-du/rcar_cmm.c @@ -0,0 +1,292 @@ +// 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/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm.h> + +#include <drm/drm_atomic.h> + +#include "rcar_cmm.h" + +#define CM2_LUT_CTRL 0x0000 +#define CM2_LUT_CTRL_EN BIT(0) +#define CM2_LUT_TBLA_BASE 0x0600 +#define CM2_LUT_TBLA(__i) (CM2_LUT_TBLA_BASE + (__i) * 4) + +struct rcar_cmm { + struct clk *clk; + void __iomem *base; + bool enabled; + + /* + * restore: LUT restore flag + * running: LUT operating flag + * size: Number of programmed entries in the LUT table + * table: Scratch buffer where to store the LUT table entries to be + * later restored. + */ + struct { + bool restore; + bool running; + unsigned int size; + struct drm_color_lut 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); +} + +static void rcar_cmm_lut_write(struct rcar_cmm *rcmm, unsigned int size, + struct drm_color_lut *lut) +{ + unsigned int i; + + for (i = 0; i < size; ++i) { + struct drm_color_lut *entry = &lut[i]; + + u32 val = (entry->red & 0xff) << 16 | + (entry->green & 0xff) << 8 | + (entry->blue & 0xff); + rcar_cmm_write(rcmm, CM2_LUT_TBLA(i), val); + } +} + +/** + * rcar_cmm_setup() - configure the CMM unit + * + * @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); + unsigned int i; + + if (config->lut.size > CMM_GAMMA_LUT_SIZE) + return -EINVAL; + + /* + * As cmm_setup is called by atomic commit tail helper, it might be + * called before enabling the CRTC (which calls cmm_enable()). + */ + if (!rcmm->enabled) { + if (!config->lut.enable) + return 0; + + /* + * Store the LUT table entries in the scratch buffer to be later + * programmed at enable time. + */ + for (i = 0; i < config->lut.size; ++i) + rcmm->lut.table[i] = config->lut.table[i]; + + rcmm->lut.size = config->lut.size; + rcmm->lut.restore = true; + + return 0; + } + + /* Stop LUT operations, if requested. */ + if (rcmm->lut.running && !config->lut.enable) { + rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0); + rcmm->lut.running = 0; + rcmm->lut.size = 0; + + return 0; + } + + /* Enable LUT and program the new gamma table values. */ + if (!rcmm->lut.running) { + rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_EN); + rcmm->lut.running = true; + } + + rcar_cmm_lut_write(rcmm, config->lut.size, config->lut.table); + rcmm->lut.size = config->lut.size; + + 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; + + ret = clk_prepare_enable(rcmm->clk); + if (ret) + return ret; + + /* Apply the LUT table values saved at cmm_setup time. */ + if (rcmm->lut.restore) { + rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_EN); + rcar_cmm_lut_write(rcmm, rcmm->lut.size, rcmm->lut.table); + + rcmm->lut.restore = false; + rcmm->lut.running = true; + } + + rcmm->enabled = true; + + return 0; +} +EXPORT_SYMBOL_GPL(rcar_cmm_enable); + +/** + * rcar_cmm_disable() - disable the CMM unit + * + * Disable the CMM unit by stopping the parent clock. + * + * @pdev: The platform device associated with the CMM instance + */ +void rcar_cmm_disable(struct platform_device *pdev) +{ + struct rcar_cmm *rcmm = platform_get_drvdata(pdev); + + rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0); + + clk_disable_unprepare(rcmm->clk); + + rcmm->lut.restore = false; + rcmm->lut.running = false; + rcmm->lut.size = 0; + + rcmm->enabled = false; +} +EXPORT_SYMBOL_GPL(rcar_cmm_disable); + +#ifdef CONFIG_PM_SLEEP +static int rcar_cmm_pm_suspend(struct device *dev) +{ + struct rcar_cmm *rcmm = dev_get_drvdata(dev); + unsigned int i; + + if (!(rcmm->lut.running || rcmm->lut.restore)) + return 0; + + /* Save the LUT table entries in the scratch buffer table. */ + for (i = 0; i < rcmm->lut.size; ++i) { + int entry = rcar_cmm_read(rcmm, CM2_LUT_TBLA(i)); + struct drm_color_lut *lut = &rcmm->lut.table[i]; + + lut->blue = entry & 0xff; + lut->green = (entry >> 8) & 0xff; + lut->red = (entry >> 16) & 0xff; + } + + rcmm->lut.restore = true; + rcmm->lut.running = false; + + rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0); + + return 0; +} + +static int rcar_cmm_pm_resume(struct device *dev) +{ + struct rcar_cmm *rcmm = dev_get_drvdata(dev); + + if (!rcmm->lut.restore) + return 0; + + /* Program the LUT entries saved at suspend time. */ + rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_EN); + rcar_cmm_lut_write(rcmm, rcmm->lut.size, rcmm->lut.table); + rcmm->lut.running = true; + rcmm->lut.restore = false; + + return 0; +} +#endif + +static const struct dev_pm_ops rcar_cmm_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(rcar_cmm_pm_suspend, rcar_cmm_pm_resume) +}; + +static int rcar_cmm_probe(struct platform_device *pdev) +{ + struct rcar_cmm *rcmm; + struct resource *res; + resource_size_t size; + + 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); + size = resource_size(res); + if (!devm_request_mem_region(&pdev->dev, res->start, size, + dev_name(&pdev->dev))) { + dev_err(&pdev->dev, + "can't request region for resource %pR\n", res); + return -EBUSY; + } + + rcmm->base = devm_ioremap_nocache(&pdev->dev, res->start, size); + if (IS_ERR(rcmm->base)) + return PTR_ERR(rcmm->base); + + rcmm->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(rcmm->clk)) { + dev_err(&pdev->dev, "Failed to get CMM clock"); + return PTR_ERR(rcmm->clk); + } + + return 0; +} + +static const struct of_device_id rcar_cmm_of_table[] = { + { .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, + .driver = { + .name = "rcar-cmm", + .pm = &rcar_cmm_pm_ops, + .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..8744e72f32cd --- /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 platform_device; +struct drm_color_lut; + +/** + * struct rcar_cmm_config - CMM configuration + * + * @lut: 1D-LUT configuration + * @lut.enable: 1D-LUT enable flag + * @lut.table: 1D-LUT table entries. + * @lut.size 1D-LUT number of entries. Max is 256. + */ +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__ */