[PATCH v1 7/7] drm: add Atmel LCDC display controller support
Sam Ravnborg
sam at ravnborg.org
Sun Aug 12 18:46:29 UTC 2018
This is a DRM based driver for the Atmel LCDC IP.
There exist today a framebuffer based driver and
this is a re-implmentation of the same on top of DRM.
The rewrite was based on the original fbdev driver
but the driver has also seen inspiration from
the atmel-hlcdc_dc driver and others.
The driver is not a full replacement:
- STN displays are not supported
Binding support is missing but most of the
STN specific functionality is otherwise ported
from the fbdev driver.
- gamma support is missing
The driver utilises drm_simple_kms_helper and
this helper lacks support for settting up gamma
- modesetting is not checked (see TODO in file)
- support for extra modes as applicable (and lcd-wiring-mode)
- support for AVR32 (is it relevant?)
Signed-off-by: Sam Ravnborg <sam at ravnborg.org>
Cc: Nicolas Ferre <nicolas.ferre at atmel.com>
Cc: Boris Brezillon <boris.brezillon at free-electrons.com>
Cc: Alexandre Belloni <alexandre.belloni at bootlin.com>
---
MAINTAINERS | 7 +
drivers/gpu/drm/atmel/Kconfig | 12 +
drivers/gpu/drm/atmel/Makefile | 2 +
drivers/gpu/drm/atmel/atmel_lcdc-dc.c | 1094 +++++++++++++++++++++++++++++++++
4 files changed, 1115 insertions(+)
create mode 100644 drivers/gpu/drm/atmel/atmel_lcdc-dc.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 09ce76a9a1dc..0a594d02a7c0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4685,6 +4685,13 @@ F: drivers/gpu/drm/atmel/atmel-hlcdc*
F: Documentation/devicetree/bindings/display/atmel/
T: git git://anongit.freedesktop.org/drm/drm-misc
+DRM DRIVERS FOR ATMEL LCDC
+M: Sam Ravnborg <sam at ravnborg.org>
+L: dri-devel at lists.freedesktop.org
+S: Maintained
+F: drivers/gpu/drm/atmel/atmel-lcdc*
+F: Documentation/devicetree/bindings/display/atmel/
+
DRM DRIVERS FOR BRIDGE CHIPS
M: Archit Taneja <architt at codeaurora.org>
M: Andrzej Hajda <a.hajda at samsung.com>
diff --git a/drivers/gpu/drm/atmel/Kconfig b/drivers/gpu/drm/atmel/Kconfig
index 7cd3862f9d18..c4c6150f271a 100644
--- a/drivers/gpu/drm/atmel/Kconfig
+++ b/drivers/gpu/drm/atmel/Kconfig
@@ -14,3 +14,15 @@ config DRM_ATMEL_HLCDC
help
Choose this option if you have an ATMEL SoC with an HLCDC display
controller (i.e. at91sam9n12, at91sam9x5 family or sama5d3 family).
+
+config DRM_ATMEL_LCDC
+ tristate "DRM Support for ATMEL LCDC Display Controller"
+ depends on DRM && OF && COMMON_CLK && MFD_ATMEL_LCDC && ARM
+ select DRM_ATMEL
+ select DRM_GEM_CMA_HELPER
+ select DRM_KMS_HELPER
+ select DRM_KMS_CMA_HELPER
+ select DRM_PANEL
+ help
+ Choose this option if you have an ATMEL SoC with an LCDC display
+ controller (only at91sam9263 or at91sam9rl).
diff --git a/drivers/gpu/drm/atmel/Makefile b/drivers/gpu/drm/atmel/Makefile
index 49dc89f36b73..9fdfada613d2 100644
--- a/drivers/gpu/drm/atmel/Makefile
+++ b/drivers/gpu/drm/atmel/Makefile
@@ -5,3 +5,5 @@ atmel-hlcdc-dc-y := atmel_hlcdc_crtc.o \
atmel_hlcdc_plane.o
obj-$(CONFIG_DRM_ATMEL_HLCDC) += atmel-hlcdc-dc.o
+
+obj-$(CONFIG_DRM_ATMEL_LCDC) += atmel_lcdc-dc.o
diff --git a/drivers/gpu/drm/atmel/atmel_lcdc-dc.c b/drivers/gpu/drm/atmel/atmel_lcdc-dc.c
new file mode 100644
index 000000000000..275a09e2e100
--- /dev/null
+++ b/drivers/gpu/drm/atmel/atmel_lcdc-dc.c
@@ -0,0 +1,1094 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Sam Ravnborg
+ *
+ * The driver is based on atmel_lcdfb which is:
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * Atmel LCD Controller Display Controller.
+ * A sub-device of the Atmel LCDC IP.
+ *
+ * The Atmel LCD Controller supports in the following configuration:
+ * - TFT only, with BGR565, 8 bits/pixel
+ * - Resolution up to 2048x2048
+ * - Single plane, crtc, one fixed output
+ *
+ * Features not (yet) ported from atmel_lcdfb:
+ * - Support for extra modes (and configurable intensify bit)
+ * - Check modesetting support - lcdc_dc_display_check()
+ * - set color / palette handling
+ * - support for STN displays (partly implemented)
+ * - AVR32 support (relevant?)
+ */
+
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/atmel-lcdc.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/irqreturn.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+
+#include <video/videomode.h>
+
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_vblank.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_of.h>
+
+/* Parameters */
+#define ATMEL_LCDC_DMA_BURST_LEN 8 /* words */
+
+/**
+ * struct atmel_lcdc_dc_desc - CPU specific configuration properties
+ */
+struct atmel_lcdc_dc_desc {
+ int guard_time;
+ int fifo_size;
+ int min_width;
+ int min_height;
+ int max_width;
+ int max_height;
+ bool have_hozval;
+ bool have_alt_pixclock;
+};
+
+/* private data */
+struct lcdc_dc {
+ const struct atmel_lcdc_dc_desc *desc;
+ struct atmel_mfd_lcdc *mfd_lcdc;
+ struct regulator *lcd_supply;
+ struct drm_fbdev_cma *fbdev;
+ struct drm_bridge *bridge;
+ struct drm_panel *panel;
+ struct regmap *regmap;
+ struct device *dev;
+
+ struct drm_simple_display_pipe pipe;
+ struct work_struct reset_lcdc_work;
+ struct drm_connector connector;
+};
+
+/* Configuration of individual CPU's */
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9261 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = true,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9263 = {
+ .guard_time = 1,
+ .fifo_size = 2048,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9g10 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = true,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9g45 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = true,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9g46 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9m10 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9m11 = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = false,
+};
+
+static const struct atmel_lcdc_dc_desc atmel_lcdc_dc_at91sam9rl = {
+ .guard_time = 1,
+ .fifo_size = 512,
+ .min_width = 0,
+ .min_height = 0,
+ .max_width = 2048,
+ .max_height = 2048,
+ .have_hozval = false,
+ .have_alt_pixclock = false,
+};
+
+static const struct of_device_id atmel_lcdc_of_match[] = {
+ {
+ .compatible = "atmel,at91sam9261-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9261,
+ }, {
+ .compatible = "atmel,at91sam9263-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9263,
+ }, {
+ .compatible = "atmel,at91sam9g10-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9g10,
+ }, {
+ .compatible = "atmel,at91sam9g45-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9g45,
+ }, {
+ .compatible = "atmel,at91sam9g46-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9g46,
+ }, {
+ .compatible = "atmel,at91sam9m10-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9m10,
+ }, {
+ .compatible = "atmel,at91sam9m11-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9m11,
+ }, {
+ .compatible = "atmel,at91sam9rl-lcdc-mfd",
+ .data = &atmel_lcdc_dc_at91sam9rl,
+ },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, atmel_lcdc_of_match);
+
+/*
+ * The Atmel LCD controller display-controller supports several formats but
+ * this driver supports only a small subset.
+ * TODO: atmel_lcdfb supports more - port it over
+ * Maybe actual wiring will impact mode support?
+ */
+static const u32 lcdc_dc_formats[] = {
+ DRM_FORMAT_BGR565,
+};
+
+/* Start LCD Controller (DMA + PWR) */
+static void lcdc_dc_start(struct lcdc_dc *lcdc_dc)
+{
+ // Enable DMA
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_DMACON, ATMEL_LCDC_DMAEN);
+ // Enable LCD
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_PWRCON,
+ (lcdc_dc->desc->guard_time << ATMEL_LCDC_GUARDT_OFFSET)
+ | ATMEL_LCDC_PWR);
+}
+
+/* Stop LCD Controller (PWR + DMA) */
+static void lcdc_dc_stop(struct lcdc_dc *lcdc_dc)
+{
+ unsigned int pwrcon;
+
+ might_sleep();
+
+ /* Turn off the LCD controller and the DMA controller */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_PWRCON,
+ lcdc_dc->desc->guard_time << ATMEL_LCDC_GUARDT_OFFSET);
+
+ /* Wait for the LCDC core to become idle */
+ regmap_read_poll_timeout(lcdc_dc->regmap, ATMEL_LCDC_PWRCON, pwrcon,
+ !(pwrcon & ATMEL_LCDC_BUSY), 100, 10000);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_DMACON, !(ATMEL_LCDC_DMAEN));
+}
+
+static void lcdc_dc_start_clock(struct lcdc_dc *lcdc_dc)
+{
+ clk_prepare_enable(lcdc_dc->mfd_lcdc->bus_clk);
+ clk_prepare_enable(lcdc_dc->mfd_lcdc->lcdc_clk);
+}
+
+static void lcdc_dc_stop_clock(struct lcdc_dc *lcdc_dc)
+{
+ clk_disable_unprepare(lcdc_dc->mfd_lcdc->bus_clk);
+ clk_disable_unprepare(lcdc_dc->mfd_lcdc->lcdc_clk);
+}
+
+static int lcdc_dc_display_check(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *pstate,
+ struct drm_crtc_state *cstate)
+{
+ const struct drm_display_mode *dmode;
+ struct drm_framebuffer *old_fb;
+ struct drm_framebuffer *fb;
+
+ dmode = &cstate->mode;
+ old_fb = pipe->plane.state->fb;
+ fb = pstate->fb;
+
+ /* Check timing? */
+ /* TODO */
+
+ return 0;
+}
+
+/* Horizontal size of LCD module - configuration dependent */
+static unsigned int compute_hozval(struct lcdc_dc *lcdc_dc, unsigned int width)
+{
+ unsigned int valid_lcdd_data_line;
+ unsigned int hoz_display_size;
+ unsigned int disptype;
+ unsigned int scanmode;
+ unsigned int ifwidth;
+ unsigned int lcdcon2;
+
+ if (!lcdc_dc->desc->have_hozval)
+ return width;
+
+ regmap_read(lcdc_dc->regmap, ATMEL_LCDC_LCDCON2, &lcdcon2);
+ disptype = lcdcon2 & ATMEL_LCDC_DISTYPE;
+
+ if (disptype == ATMEL_LCDC_DISTYPE_TFT)
+ return width;
+
+ ifwidth = lcdcon2 & ATMEL_LCDC_IFWIDTH;
+ scanmode = lcdcon2 & ATMEL_LCDC_SCANMOD;
+
+ /*
+ * STN display
+ * Based on algorithm from datasheet calculate hozval
+ */
+ if (disptype == ATMEL_LCDC_DISTYPE_STNCOLOR)
+ hoz_display_size = width * 3;
+ else
+ hoz_display_size = width;
+
+ switch (ifwidth) {
+ case ATMEL_LCDC_IFWIDTH_4:
+ valid_lcdd_data_line = 4;
+ break;
+ case ATMEL_LCDC_IFWIDTH_8:
+ if (scanmode == ATMEL_LCDC_SCANMOD_DUAL)
+ valid_lcdd_data_line = 4;
+ else
+ valid_lcdd_data_line = 8;
+ break;
+ default:
+ valid_lcdd_data_line = 8;
+ break;
+ }
+
+ return DIV_ROUND_UP(hoz_display_size, valid_lcdd_data_line);
+}
+
+static void set_vertical_timing(struct lcdc_dc *lcdc_dc,
+ struct drm_display_mode *dmode)
+{
+ unsigned int tim1;
+ unsigned int vfp;
+ unsigned int vbp;
+ unsigned int vpw;
+ unsigned int vhdly;
+
+ /* VFP: Vertical Front Porch */
+ vfp = dmode->vsync_start - dmode->vdisplay;
+
+ /* VBP: Vertical Back Porch */
+ vbp = dmode->vtotal - dmode->vsync_end;
+
+ /* VPW: Vertical Synchronization pulse width */
+ vpw = dmode->vsync_end - dmode->vsync_start - 1;
+
+ /* VHDLY: Vertical to horizontal delay */
+ vhdly = 0;
+
+ tim1 = vfp << ATMEL_LCDC_VFP_OFFSET |
+ vbp << ATMEL_LCDC_VBP_OFFSET |
+ vpw << ATMEL_LCDC_VPW_OFFSET |
+ vhdly << ATMEL_LCDC_VHDLY_OFFSET;
+
+ DRM_DEV_DEBUG(lcdc_dc->dev, " TIM1 = %08x\n", tim1);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_TIM1, tim1);
+}
+
+static void set_horizontal_timing(struct lcdc_dc *lcdc_dc,
+ struct drm_display_mode *dmode)
+{
+ unsigned int tim2;
+ unsigned int hbp;
+ unsigned int hpw;
+ unsigned int hfp;
+
+ /* HBP: Horizontal Back Porch */
+ hbp = dmode->htotal - dmode->hsync_end - 1;
+
+ /* HPW: Horizontal synchronization pulse width */
+ hpw = dmode->hsync_end - dmode->hsync_start - 1;
+
+ /* HFP: Horizontal Front Porch */
+ hfp = dmode->hsync_start - dmode->hdisplay - 2;
+
+ tim2 = hbp << ATMEL_LCDC_HBP_OFFSET |
+ hpw << ATMEL_LCDC_HPW_OFFSET |
+ hfp << ATMEL_LCDC_HFP_OFFSET;
+
+ DRM_DEV_DEBUG(lcdc_dc->dev, " TIM2 = %08x\n", tim2);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_TIM2, tim2);
+}
+
+static void lcdc_dc_crtc_mode_set_nofb(struct lcdc_dc *lcdc_dc)
+{
+ struct drm_display_mode *dmode;
+ unsigned int hozval_linesz;
+ unsigned int value;
+
+ dmode = &lcdc_dc->pipe.crtc.state->adjusted_mode;
+
+ /* Vertical & horizontal timing */
+ set_vertical_timing(lcdc_dc, dmode);
+ set_horizontal_timing(lcdc_dc, dmode);
+
+ /* Horizontal value (aka line size) */
+ hozval_linesz = compute_hozval(lcdc_dc, dmode->crtc_hdisplay);
+
+ /* Display size */
+ value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;
+ value |= dmode->crtc_vdisplay - 1;
+ DRM_DEV_DEBUG(lcdc_dc->dev, " LCDFRMCFG = %08x\n", value);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_LCDFRMCFG, value);
+
+ /* FIFO Threshold: Use formula from data sheet */
+ value = lcdc_dc->desc->fifo_size - (2 * ATMEL_LCDC_DMA_BURST_LEN + 3);
+ DRM_DEV_DEBUG(lcdc_dc->dev, " FIFO = %08x\n", value);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_FIFO, value);
+
+ /*
+ * Toggle LCD_MODE every frame
+ * Note: register not documented, this is from atmel_lcdfb
+ */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_MVAL, 0);
+}
+
+static void lcdc_dc_enable(struct lcdc_dc *lcdc_dc,
+ struct drm_device *drm,
+ struct drm_crtc *crtc)
+{
+ const struct drm_format_info *format;
+ struct drm_display_mode *dmode;
+ unsigned long clk_value_khz;
+ unsigned int pix_factor;
+ unsigned int lcdcon1;
+ unsigned int lcdcon2;
+ u32 bus_flags;
+
+ dmode = &lcdc_dc->pipe.crtc.state->adjusted_mode;
+ format = crtc->primary->state->fb->format;
+
+ /* Control register 1 */
+
+ /* Set pixel clock */
+ if (lcdc_dc->desc->have_alt_pixclock)
+ pix_factor = 1;
+ else
+ pix_factor = 2;
+
+ clk_value_khz = clk_get_rate(lcdc_dc->mfd_lcdc->lcdc_clk) / 1000;
+ lcdcon1 = DIV_ROUND_UP(clk_value_khz, dmode->clock);
+
+ if (lcdcon1 < pix_factor) {
+ DRM_DEV_INFO(lcdc_dc->dev, "Bypassing pixel clock divider\n");
+ regmap_write(lcdc_dc->regmap,
+ ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
+ } else {
+
+ lcdcon1 = (lcdcon1 / pix_factor) - 1;
+ DRM_DEV_DEBUG(lcdc_dc->dev, "CLKVAL = 0x%08x\n", lcdcon1);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_LCDCON1,
+ lcdcon1 << ATMEL_LCDC_CLKVAL_OFFSET);
+ dmode->clock = clk_value_khz / (pix_factor * (lcdcon1 + 1));
+ DRM_DEV_DEBUG(lcdc_dc->dev, "updated pixclk: %u KHz\n",
+ dmode->clock);
+ }
+
+ /* Control register 2 */
+ /* Only TFT supported (Controller supports STN too) */
+ lcdcon2 = ATMEL_LCDC_DISTYPE_TFT;
+
+ /* scan mode (STN only) */
+ if (dmode->flags & DRM_MODE_FLAG_DBLSCAN)
+ lcdcon2 |= ATMEL_LCDC_SCANMOD_DUAL;
+ else
+ lcdcon2 |= ATMEL_LCDC_SCANMOD_SINGLE;
+
+ /* Interface width 4 bits (STN only) */
+ lcdcon2 |= ATMEL_LCDC_IFWIDTH_4;
+
+ /* bits per pixel */
+ switch (format->depth) {
+ case 1:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_1;
+ break;
+ case 2:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_2;
+ break;
+ case 4:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_4;
+ break;
+ case 8:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_8;
+ break;
+ case 15:
+ /* fall through */
+ case 16:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_16;
+ break;
+ case 24:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_24;
+ break;
+ case 32:
+ lcdcon2 |= ATMEL_LCDC_PIXELSIZE_32;
+ break;
+ default:
+ DRM_DEV_ERROR(lcdc_dc->dev, "Unexpected depth (%d)",
+ format->depth);
+ break;
+ }
+
+ /* Polarity normal */
+ lcdcon2 |= ATMEL_LCDC_INVVD_NORMAL;
+
+ /* vsync polarity */
+ if (dmode->flags & DRM_MODE_FLAG_PVSYNC)
+ lcdcon2 |= ATMEL_LCDC_INVFRAME_INVERTED;
+ else
+ lcdcon2 |= ATMEL_LCDC_INVFRAME_NORMAL;
+
+ /* hsync polarity */
+ if (dmode->flags & DRM_MODE_FLAG_PHSYNC)
+ lcdcon2 |= ATMEL_LCDC_INVLINE_INVERTED;
+ else
+ lcdcon2 |= ATMEL_LCDC_INVLINE_NORMAL;
+
+ bus_flags = lcdc_dc->connector.display_info.bus_flags;
+
+ /* dot clock (pix clock) polarity */
+ if (bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
+ lcdcon2 |= ATMEL_LCDC_INVCLK_INVERTED;
+ else
+ lcdcon2 |= ATMEL_LCDC_INVCLK_NORMAL;
+
+ /* Date Enable polarity */
+ if (bus_flags & DRM_BUS_FLAG_DE_LOW)
+ lcdcon2 |= ATMEL_LCDC_INVDVAL_INVERTED;
+ else
+ lcdcon2 |= ATMEL_LCDC_INVDVAL_NORMAL;
+
+ /* Clock is always active */
+ lcdcon2 |= ATMEL_LCDC_CLKMOD_ALWAYSACTIVE;
+
+ /* Memory layout */
+ if (format->format & DRM_FORMAT_BIG_ENDIAN)
+ lcdcon2 |= ATMEL_LCDC_MEMOR_BIG;
+ else
+ lcdcon2 |= ATMEL_LCDC_MEMOR_LITTLE;
+
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_LCDCON2, lcdcon2);
+
+ lcdc_dc_start(lcdc_dc);
+
+ drm_crtc_vblank_on(crtc);
+}
+
+static void lcdc_dc_display_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *cstate,
+ struct drm_plane_state *plane_state)
+{
+ struct lcdc_dc *lcdc_dc;
+ struct drm_device *drm;
+ struct drm_crtc *crtc;
+ int ret;
+
+ crtc = &pipe->crtc;
+ drm = crtc->dev;
+ lcdc_dc = drm->dev_private;
+
+ ret = regulator_enable(lcdc_dc->lcd_supply);
+ if (ret)
+ DRM_DEV_ERROR(lcdc_dc->dev, "regulator_enable failed (%d)",
+ ret);
+
+ drm_panel_prepare(lcdc_dc->panel);
+ lcdc_dc_crtc_mode_set_nofb(lcdc_dc);
+
+ /*
+ * drm_simple_kms_helper have no support for gamma setup.
+ * Add: lcdc_dc_setcolor(lcdc_dc, crtc); when we have it
+ */
+ lcdc_dc_enable(lcdc_dc, drm, crtc);
+
+ drm_panel_enable(lcdc_dc->panel);
+}
+
+static void lcdc_dc_display_disable(struct drm_simple_display_pipe *pipe)
+{
+ struct lcdc_dc *lcdc_dc;
+ struct drm_device *drm;
+ struct drm_crtc *crtc;
+
+ crtc = &pipe->crtc;
+ drm = crtc->dev;
+ lcdc_dc = drm->dev_private;
+
+ drm_crtc_vblank_off(crtc);
+
+ drm_panel_disable(lcdc_dc->panel);
+
+ lcdc_dc_stop(lcdc_dc);
+
+ drm_panel_unprepare(lcdc_dc->panel);
+ regulator_disable(lcdc_dc->lcd_supply);
+}
+
+/* Update DMA config */
+static void lcdc_dc_update_dma(struct lcdc_dc *lcdc_dc,
+ struct drm_simple_display_pipe *pipe)
+{
+ struct drm_plane_state *plane_state;
+ struct drm_framebuffer *fb;
+ unsigned int burst_length;
+ unsigned int frame_size;
+ dma_addr_t dma_addr;
+
+ plane_state = pipe->plane.state;
+ fb = plane_state->fb;
+
+ if (fb) {
+ unsigned int dmafrmcfg;
+
+ dma_addr = drm_fb_cma_get_gem_addr(fb, pipe->plane.state, 0);
+
+ /* Set frame buffer DMA base address */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_DMABADDR1, dma_addr);
+
+ /*
+ * Set frame size and burst length
+ * Frame_size equals size of visible area * bits / 32
+ * (size in 32 bit words)
+ */
+ frame_size = plane_state->crtc_w * plane_state->crtc_h;
+ frame_size = (frame_size * fb->format->depth) / 32;
+
+ burst_length = ATMEL_LCDC_DMA_BURST_LEN - 1;
+
+ dmafrmcfg = frame_size;
+ dmafrmcfg |= burst_length << ATMEL_LCDC_BLENGTH_OFFSET;
+
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_DMAFRMCFG, dmafrmcfg);
+ }
+}
+
+static void lcdc_dc_update_event(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_pending_vblank_event *event;
+ struct drm_crtc *crtc;
+
+ crtc = &pipe->crtc;
+ if (!crtc)
+ return;
+
+ spin_lock_irq(&crtc->dev->event_lock);
+ event = crtc->state->event;
+ if (event) {
+ crtc->state->event = NULL;
+
+ if (drm_crtc_vblank_get(crtc) == 0)
+ drm_crtc_arm_vblank_event(crtc, event);
+ else
+ drm_crtc_send_vblank_event(crtc, event);
+ }
+ spin_unlock_irq(&crtc->dev->event_lock);
+}
+
+static void lcdc_dc_display_update(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *old_pstate)
+{
+ struct drm_device *drm;
+ struct lcdc_dc *lcdc_dc;
+
+ drm = pipe->crtc.dev;
+ lcdc_dc = drm->dev_private;
+
+ /* Re-initialize the DMA engine... */
+ lcdc_dc_update_dma(lcdc_dc, pipe);
+
+ /* vblank event handling */
+ lcdc_dc_update_event(pipe);
+}
+
+static int lcdc_dc_display_enable_vblank(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_crtc *crtc;
+ struct lcdc_dc *lcdc_dc;
+
+ crtc = &pipe->crtc;
+ lcdc_dc = crtc->dev->dev_private;
+
+ /* Last line interrupt enable */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_IER, ATMEL_LCDC_LSTLNI);
+
+ return 0;
+}
+
+static void lcdc_dc_display_disable_vblank(struct drm_simple_display_pipe *pipe)
+{
+ struct drm_crtc *crtc;
+ struct lcdc_dc *lcdc_dc;
+
+ crtc = &pipe->crtc;
+ lcdc_dc = crtc->dev->dev_private;
+
+ /* Last line interrupt disable */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_IDR, ATMEL_LCDC_LSTLNI);
+}
+
+static const struct drm_simple_display_pipe_funcs lcdc_dc_display_funcs = {
+ .check = lcdc_dc_display_check,
+ .enable = lcdc_dc_display_enable,
+ .disable = lcdc_dc_display_disable,
+ .update = lcdc_dc_display_update,
+ .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
+ .enable_vblank = lcdc_dc_display_enable_vblank,
+ .disable_vblank = lcdc_dc_display_disable_vblank,
+};
+
+static const struct drm_mode_config_funcs mode_config_funcs = {
+ .fb_create = drm_gem_fb_create,
+ .atomic_check = drm_atomic_helper_check,
+ .atomic_commit = drm_atomic_helper_commit,
+};
+
+/* scheduled worker to reset LCD */
+static void reset_lcdc_work(struct work_struct *work)
+{
+ struct lcdc_dc *lcdc_dc;
+
+ lcdc_dc = container_of(work, struct lcdc_dc, reset_lcdc_work);
+
+ lcdc_dc_stop(lcdc_dc);
+ lcdc_dc_start(lcdc_dc);
+}
+
+static irqreturn_t lcdc_dc_irq_handler(int irq, void *arg)
+{
+ struct lcdc_dc *lcdc_dc;
+ struct drm_device *drm;
+ unsigned int status;
+ struct device *dev;
+ unsigned int imr;
+ unsigned int isr;
+
+ drm = arg;
+ lcdc_dc = drm->dev_private;
+ dev = lcdc_dc->dev;
+
+ regmap_read(lcdc_dc->regmap, ATMEL_LCDC_IMR, &imr);
+ regmap_read(lcdc_dc->regmap, ATMEL_LCDC_ISR, &isr);
+ status = imr & isr;
+ if (!status)
+ return IRQ_NONE;
+
+ if (status & ATMEL_LCDC_LSTLNI)
+ drm_crtc_handle_vblank(&lcdc_dc->pipe.crtc);
+
+ if (status & ATMEL_LCDC_UFLWI) {
+ DRM_DEV_INFO(dev, "FIFO underflow %#x\n", status);
+ /* reset DMA and FIFO to avoid screen shifting */
+ schedule_work(&lcdc_dc->reset_lcdc_work);
+ }
+ if (status & ATMEL_LCDC_OWRI)
+ DRM_DEV_INFO(dev, "FIFO overwrite interrupt");
+
+ if (status & ATMEL_LCDC_MERI)
+ DRM_DEV_INFO(dev, "DMA memory error");
+
+ /* Clear all reported (from ISR) interrupts */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_ICR, isr);
+
+ return IRQ_HANDLED;
+}
+
+static int lcdc_dc_irq_postinstall(struct drm_device *dev)
+{
+ struct lcdc_dc *lcdc_dc;
+ unsigned int ier;
+
+ lcdc_dc = dev->dev_private;
+
+ ier = 0;
+ /* FIFO underflow interrupt enable */
+ ier |= ATMEL_LCDC_UFLWI;
+ /* FIFO overwrite interrupt enable */
+ ier |= ATMEL_LCDC_OWRI;
+ /* DMA memory error interrupt enable */
+ ier |= ATMEL_LCDC_MERI;
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_IER, ier);
+
+ return 0;
+}
+
+static void lcdc_dc_irq_uninstall(struct drm_device *dev)
+{
+ struct lcdc_dc *lcdc_dc;
+ unsigned int isr;
+
+ lcdc_dc = dev->dev_private;
+
+ /* disable all interrupts */
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_IDR, ~0);
+ regmap_write(lcdc_dc->regmap, ATMEL_LCDC_ICR, ~0);
+
+ /* Clear any pending interrupts */
+ regmap_read(lcdc_dc->regmap, ATMEL_LCDC_ISR, &isr);
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(lcdc_dc_drm_fops);
+
+static struct drm_driver lcdc_dc_drm_driver = {
+ .driver_features = DRIVER_HAVE_IRQ |
+ DRIVER_GEM |
+ DRIVER_MODESET |
+ DRIVER_PRIME |
+ DRIVER_ATOMIC,
+ .name = "atmel-lcdc",
+ .desc = "Atmel LCD Display Controller DRM",
+ .date = "20180808",
+ .major = 1,
+ .minor = 0,
+ .patchlevel = 0,
+
+ .lastclose = drm_fb_helper_lastclose,
+ .fops = &lcdc_dc_drm_fops,
+
+ .irq_handler = lcdc_dc_irq_handler,
+ .irq_preinstall = lcdc_dc_irq_uninstall,
+ .irq_postinstall = lcdc_dc_irq_postinstall,
+ .irq_uninstall = lcdc_dc_irq_uninstall,
+
+ .dumb_create = drm_gem_cma_dumb_create,
+
+ .gem_print_info = drm_gem_cma_print_info,
+ .gem_vm_ops = &drm_gem_cma_vm_ops,
+
+ .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
+ .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
+
+ .gem_prime_import = drm_gem_prime_import,
+ .gem_prime_export = drm_gem_prime_export,
+
+ .gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
+ .gem_free_object_unlocked = drm_gem_cma_free_object,
+
+ .gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+ .gem_prime_vmap = drm_gem_cma_prime_vmap,
+ .gem_prime_vunmap = drm_gem_cma_prime_vunmap,
+ .gem_prime_mmap = drm_gem_cma_prime_mmap,
+};
+
+static int lcdc_dc_modeset_init(struct lcdc_dc *lcdc_dc, struct drm_device *drm)
+{
+ struct drm_bridge *bridge;
+ struct drm_panel *panel;
+ struct device_node *np;
+ struct device *dev;
+ int ret;
+
+ dev = drm->dev;
+
+ drm_mode_config_init(drm);
+ drm->mode_config.min_width = lcdc_dc->desc->min_width;
+ drm->mode_config.min_height = lcdc_dc->desc->min_height;
+ drm->mode_config.max_width = lcdc_dc->desc->max_width;
+ drm->mode_config.max_height = lcdc_dc->desc->max_height;
+ drm->mode_config.funcs = &mode_config_funcs;
+
+ np = dev->of_node;
+ /* port at 0 is the output port */
+ ret = drm_of_find_panel_or_bridge(np, 0, 0, &panel, &bridge);
+ if (ret && ret != -ENODEV) {
+ DRM_DEV_ERROR(dev, "Failed to find panel (%d)\n", ret);
+ goto err_out;
+ }
+
+ bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_Unknown);
+ if (IS_ERR(bridge)) {
+ ret = PTR_ERR(bridge);
+ DRM_DEV_ERROR(dev, "Failed to add bridge (%d)", ret);
+ goto err_panel_remove;
+ }
+
+ lcdc_dc->panel = panel;
+ lcdc_dc->bridge = bridge;
+
+ ret = drm_simple_display_pipe_init(drm,
+ &lcdc_dc->pipe,
+ &lcdc_dc_display_funcs,
+ lcdc_dc_formats,
+ ARRAY_SIZE(lcdc_dc_formats),
+ NULL,
+ &lcdc_dc->connector);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "Failed to init display pipe (%d)\n", ret);
+ goto err_panel_remove;
+ }
+
+ ret = drm_simple_display_pipe_attach_bridge(&lcdc_dc->pipe, bridge);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "failed to attach bridge (%d)", ret);
+ goto err_panel_remove;
+ }
+
+ drm_mode_config_reset(drm);
+
+ return 0;
+
+err_panel_remove:
+ if (panel)
+ drm_panel_bridge_remove(bridge);
+
+err_out:
+ return ret;
+}
+
+static int lcdc_dc_load(struct drm_device *drm)
+{
+ const struct of_device_id *match;
+ struct platform_device *pdev;
+ struct lcdc_dc *lcdc_dc;
+ struct device *dev;
+ int ret;
+
+ dev = drm->dev;
+ pdev = to_platform_device(dev);
+
+ match = of_match_node(atmel_lcdc_of_match, dev->parent->of_node);
+ if (!match) {
+ DRM_DEV_ERROR(dev, "invalid compatible string (node=%s)",
+ dev->parent->of_node->name);
+ return -ENODEV;
+ }
+
+ if (!match->data) {
+ DRM_DEV_ERROR(dev, "invalid lcdc_dc description\n");
+ return -EINVAL;
+ }
+
+ lcdc_dc = devm_kzalloc(dev, sizeof(*lcdc_dc), GFP_KERNEL);
+ if (!lcdc_dc) {
+ DRM_DEV_ERROR(dev, "Failed to allocate lcdc_dc\n");
+ return -ENOMEM;
+ }
+
+ /* reset of lcdc might sleep and require a preemptible task context */
+ INIT_WORK(&lcdc_dc->reset_lcdc_work, reset_lcdc_work);
+
+ platform_set_drvdata(pdev, drm);
+ dev_set_drvdata(dev, lcdc_dc);
+
+ lcdc_dc->mfd_lcdc = dev_get_drvdata(dev->parent);
+ drm->dev_private = lcdc_dc;
+
+ lcdc_dc->regmap = lcdc_dc->mfd_lcdc->regmap;
+ lcdc_dc->desc = match->data;
+ lcdc_dc->dev = dev;
+
+ lcdc_dc->lcd_supply = devm_regulator_get(dev, "lcd");
+ if (IS_ERR(lcdc_dc->lcd_supply)) {
+ DRM_DEV_ERROR(dev, "Failed to get lcd-supply (%ld)\n",
+ PTR_ERR(lcdc_dc->lcd_supply));
+ lcdc_dc->lcd_supply = NULL;
+ }
+
+ lcdc_dc_start_clock(lcdc_dc);
+
+ pm_runtime_enable(dev);
+
+ ret = drm_vblank_init(drm, 1);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "failed to initialize vblank (%d)\n",
+ ret);
+ goto err_pm_runtime_disable;
+ }
+
+ ret = lcdc_dc_modeset_init(lcdc_dc, drm);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "modeset_init failed (%d)", ret);
+ goto err_pm_runtime_disable;
+ }
+
+ pm_runtime_get_sync(dev);
+ ret = drm_irq_install(drm, lcdc_dc->mfd_lcdc->irq);
+ pm_runtime_put_sync(dev);
+ if (ret < 0) {
+ DRM_DEV_ERROR(dev, "Failed to install IRQ (%d)\n", ret);
+
+ goto err_pm_runtime_disable;
+ }
+
+ /*
+ * Passing in 16 here will make the RGB656 mode the default
+ * Passing in 32 will use XRGB8888 mode
+ */
+ drm_fb_cma_fbdev_init(drm, 16, 0);
+
+ drm_kms_helper_poll_init(drm);
+
+ lcdc_dc->fbdev = drm_fbdev_cma_init(drm, 8, 1);
+ if (IS_ERR(lcdc_dc->fbdev)) {
+ ret = PTR_ERR(lcdc_dc->fbdev);
+ DRM_DEV_ERROR(dev, "Failed to init FB CMA area (%d)", ret);
+ goto err_irq_uninstall;
+ }
+
+ drm_helper_hpd_irq_event(drm);
+
+ return 0;
+
+err_irq_uninstall:
+ pm_runtime_get_sync(dev);
+ drm_irq_uninstall(drm);
+ pm_runtime_put_sync(dev);
+
+err_pm_runtime_disable:
+ pm_runtime_disable(dev);
+ lcdc_dc_stop_clock(lcdc_dc);
+
+ cancel_work_sync(&lcdc_dc->reset_lcdc_work);
+
+ return ret;
+}
+
+static void lcdc_dc_unload(struct drm_device *dev)
+{
+ struct lcdc_dc *lcdc_dc = dev->dev_private;
+
+ drm_fb_cma_fbdev_fini(dev);
+ flush_work(&lcdc_dc->reset_lcdc_work);
+ drm_kms_helper_poll_fini(dev);
+ if (lcdc_dc->panel)
+ drm_panel_bridge_remove(lcdc_dc->bridge);
+ drm_mode_config_cleanup(dev);
+
+ pm_runtime_get_sync(dev->dev);
+ drm_irq_uninstall(dev);
+ pm_runtime_put_sync(dev->dev);
+
+ dev->dev_private = NULL;
+
+ pm_runtime_disable(dev->dev);
+ lcdc_dc_stop_clock(lcdc_dc);
+ cancel_work_sync(&lcdc_dc->reset_lcdc_work);
+}
+
+
+static int lcdc_dc_probe(struct platform_device *pdev)
+{
+ struct drm_device *drm;
+ struct device *dev;
+ int ret;
+
+ dev = &pdev->dev;
+
+ drm = drm_dev_alloc(&lcdc_dc_drm_driver, dev);
+ if (IS_ERR(drm)) {
+ DRM_DEV_ERROR(dev, "Failed to allocate drm device\n");
+ return PTR_ERR(drm);
+ }
+
+ ret = lcdc_dc_load(drm);
+ if (ret)
+ goto err_put_ref;
+
+ ret = drm_dev_register(drm, 0);
+ if (ret) {
+ DRM_DEV_ERROR(dev, "Failed to register drm (%d)\n", ret);
+ goto err_unload;
+ }
+
+ return 0;
+
+err_unload:
+ lcdc_dc_unload(drm);
+
+err_put_ref:
+ drm_dev_put(drm);
+ return ret;
+}
+
+static int lcdc_dc_remove(struct platform_device *pdev)
+{
+ struct drm_device *drm;
+
+ drm = platform_get_drvdata(pdev);
+
+ drm_dev_unregister(drm);
+ lcdc_dc_unload(drm);
+ drm_dev_unref(drm);
+
+ return 0;
+}
+
+static const struct of_device_id lcdc_dc_dt_ids[] = {
+ { .compatible = "atmel,lcdc-display-controller", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, lcdc_dc_dt_ids);
+
+static struct platform_driver lcdc_dc_driver = {
+ .probe = lcdc_dc_probe,
+ .remove = lcdc_dc_remove,
+ .driver = {
+ .of_match_table = lcdc_dc_dt_ids,
+ .name = "atmel-lcdc-dc",
+ },
+};
+
+module_platform_driver(lcdc_dc_driver);
+
+MODULE_AUTHOR("Sam Ravnborg <sam at ravnborg.org>");
+MODULE_DESCRIPTION("Atmel LCDC Display Controller DRM Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:atmel-lcdc-dc");
--
2.12.0
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