Hi Eric,
manu thanks for your help.
These patches have been push on DRM misc.
I solve all issues & I will push a new version today(V5).
I create a patch on drm_gem_cma_helper.h regarding 
DEFINE_DRM_GEM_CMA_FOPS & a patch on drm_fb_cma_helper to add new 
function to get physical address.

Best regards

Yannick Fertré


On 03/21/2017 09:55 PM, Eric Anholt wrote:
> Yannick Fertre <yannick.fer...@st.com> writes:
>
>> This controller provides output signals to interface directly a variety
>> of LCD and TFT panels. These output signals are: RGB signals
>> (up to 24bpp), vertical & horizontal synchronisations, data enable and
>> the pixel clock.
>
> I've got some feedback inline that hopefully helps cut some boilerplate
> DRM code.  This looks like a complete driver, and some nice hardware as
> far as modesetting goes.
>
> If you're planning on going through drm-misc, I'd do another pass at
> review so I could give an Ack.
>
>> Change-Id: Ic1d6ade06ab7115c62e98dd21dc3981fb5948d1c
>> Signed-off-by: Yannick Fertre <yannick.fer...@st.com>
>> ---
>>  drivers/gpu/drm/Kconfig      |    3 +-
>>  drivers/gpu/drm/Makefile     |    1 +
>>  drivers/gpu/drm/stm/Kconfig  |   16 +
>>  drivers/gpu/drm/stm/Makefile |    7 +
>>  drivers/gpu/drm/stm/drv.c    |  232 +++++++
>>  drivers/gpu/drm/stm/drv.h    |   22 +
>>  drivers/gpu/drm/stm/ltdc.c   | 1422 
>> ++++++++++++++++++++++++++++++++++++++++++
>>  drivers/gpu/drm/stm/ltdc.h   |   22 +
>>  8 files changed, 1724 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/gpu/drm/stm/Kconfig
>>  create mode 100644 drivers/gpu/drm/stm/Makefile
>>  create mode 100644 drivers/gpu/drm/stm/drv.c
>>  create mode 100644 drivers/gpu/drm/stm/drv.h
>>  create mode 100644 drivers/gpu/drm/stm/ltdc.c
>>  create mode 100644 drivers/gpu/drm/stm/ltdc.h
>>
>> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
>> index 78d7fc0..dd5762a 100644
>> --- a/drivers/gpu/drm/Kconfig
>> +++ b/drivers/gpu/drm/Kconfig
>> @@ -203,7 +203,6 @@ config DRM_VGEM
>>        as used by Mesa's software renderer for enhanced performance.
>>        If M is selected the module will be called vgem.
>>
>> -
>>  source "drivers/gpu/drm/exynos/Kconfig"
>>
>>  source "drivers/gpu/drm/rockchip/Kconfig"
>> @@ -246,6 +245,8 @@ source "drivers/gpu/drm/fsl-dcu/Kconfig"
>>
>>  source "drivers/gpu/drm/tegra/Kconfig"
>>
>> +source "drivers/gpu/drm/stm/Kconfig"
>> +
>>  source "drivers/gpu/drm/panel/Kconfig"
>>
>>  source "drivers/gpu/drm/bridge/Kconfig"
>> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
>> index 59aae43..320fd86 100644
>> --- a/drivers/gpu/drm/Makefile
>> +++ b/drivers/gpu/drm/Makefile
>> @@ -81,6 +81,7 @@ obj-$(CONFIG_DRM_BOCHS) += bochs/
>>  obj-$(CONFIG_DRM_VIRTIO_GPU) += virtio/
>>  obj-$(CONFIG_DRM_MSM) += msm/
>>  obj-$(CONFIG_DRM_TEGRA) += tegra/
>> +obj-$(CONFIG_DRM_STM) += stm/
>>  obj-$(CONFIG_DRM_STI) += sti/
>>  obj-$(CONFIG_DRM_IMX) += imx/
>>  obj-$(CONFIG_DRM_MEDIATEK) += mediatek/
>> diff --git a/drivers/gpu/drm/stm/Kconfig b/drivers/gpu/drm/stm/Kconfig
>> new file mode 100644
>> index 0000000..8ef8a09
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/Kconfig
>> @@ -0,0 +1,16 @@
>> +config DRM_STM
>> +    tristate "DRM Support for STMicroelectronics SoC Series"
>> +    depends on DRM && (ARCH_STM32 || ARCH_MULTIPLATFORM)
>> +    select DRM_KMS_HELPER
>> +    select DRM_GEM_CMA_HELPER
>> +    select DRM_KMS_CMA_HELPER
>> +    select DRM_PANEL
>> +    select VIDEOMODE_HELPERS
>> +    select FB_PROVIDE_GET_FB_UNMAPPED_AREA
>> +    default y
>> +
>> +    help
>> +      Enable support for the on-chip display controller on
>> +       STMicroelectronics STM32 MCUs.
>
> Funny indentation here?
Ok, Done
>
>> +      To compile this driver as a module, choose M here: the module
>> +      will be called stm-drm.
>> diff --git a/drivers/gpu/drm/stm/Makefile b/drivers/gpu/drm/stm/Makefile
>> new file mode 100644
>> index 0000000..e114d45
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/Makefile
>> @@ -0,0 +1,7 @@
>> +ccflags-y := -Iinclude/drm
>> +
>> +stm-drm-y := \
>> +    drv.o \
>> +    ltdc.o
>> +
>> +obj-$(CONFIG_DRM_STM) += stm-drm.o
>> diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
>> new file mode 100644
>> index 0000000..d5c46c5
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/drv.c
>> @@ -0,0 +1,232 @@
>> +/*
>> + * Copyright (C) STMicroelectronics SA 2017
>> + *
>> + * Authors: Philippe Cornu <philippe.co...@st.com>
>> + *          Yannick Fertre <yannick.fer...@st.com>
>> + *          Fabien Dessenne <fabien.desse...@st.com>
>> + *          Mickael Reulier <mickael.reul...@st.com>
>> + *
>> + * License terms:  GNU General Public License (GPL), version 2
>> + */
>> +
>> +#include <linux/component.h>
>> +#include <linux/of_platform.h>
>> +
>> +#include <drm/drm_atomic.h>
>> +#include <drm/drm_atomic_helper.h>
>> +#include <drm/drm_crtc_helper.h>
>> +#include <drm/drm_fb_cma_helper.h>
>> +#include <drm/drm_gem_cma_helper.h>
>> +
>> +#include "drv.h"
>> +#include "ltdc.h"
>> +
>> +#define DRIVER_NAME         "stm"
>> +#define DRIVER_DESC         "STMicroelectronics SoC DRM"
>> +#define DRIVER_DATE         "20170209"
>> +#define DRIVER_MAJOR                1
>> +#define DRIVER_MINOR                0
>> +#define DRIVER_PATCH_LEVEL  0
>> +
>> +#define STM_MAX_FB_WIDTH            2048
>> +#define STM_MAX_FB_HEIGHT   2048 /* same as width to handle orientation */
>> +
>> +static void drv_output_poll_changed(struct drm_device *ddev)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +
>> +    drm_fbdev_cma_hotplug_event(priv->fbdev);
>> +}
>> +
>> +static const struct drm_mode_config_funcs drv_mode_config_funcs = {
>> +    .fb_create = drm_fb_cma_create,
>> +    .output_poll_changed = drv_output_poll_changed,
>> +    .atomic_check = drm_atomic_helper_check,
>> +    .atomic_commit = drm_atomic_helper_commit,
>> +};
>> +
>> +static const struct file_operations drv_driver_fops = {
>> +    .owner = THIS_MODULE,
>> +    .open = drm_open,
>> +    .release = drm_release,
>> +    .unlocked_ioctl = drm_ioctl,
>> +    .compat_ioctl = drm_compat_ioctl,
>> +    .poll = drm_poll,
>> +    .read = drm_read,
>> +    .mmap = drm_gem_cma_mmap,
>> +    .get_unmapped_area = drm_gem_cma_get_unmapped_area,
>> +};
>
> This looks like almost a candidate for the new
> DEFINE_DRM_GEM_CMA_FOPS().  Maybe that helper should conditionally add
> the drm_gem_cma_get_unmapped_area reference on !MMU?
Ok, Done
I create a patch to add get_unmapped_area to the macro.
>
>> +
>> +static void drv_lastclose(struct drm_device *ddev)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +
>> +    DRM_DEBUG("%s\n", __func__);
>> +
>> +    drm_fbdev_cma_restore_mode(priv->fbdev);
>> +}
>> +
>> +static struct drm_driver drv_driver = {
>> +    .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME |
>> +                       DRIVER_ATOMIC,
>> +    .lastclose = drv_lastclose,
>> +    .name = DRIVER_NAME,
>> +    .desc = DRIVER_DESC,
>> +    .date = DRIVER_DATE,
>> +    .major = DRIVER_MAJOR,
>> +    .minor = DRIVER_MINOR,
>> +    .patchlevel = DRIVER_PATCH_LEVEL,
>> +    .fops = &drv_driver_fops,
>> +    .dumb_create = drm_gem_cma_dumb_create,
>> +    .dumb_map_offset = drm_gem_cma_dumb_map_offset,
>> +    .dumb_destroy = drm_gem_dumb_destroy,
>> +    .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
>> +    .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
>> +    .gem_free_object_unlocked = drm_gem_cma_free_object,
>> +    .gem_vm_ops = &drm_gem_cma_vm_ops,
>> +    .gem_prime_export = drm_gem_prime_export,
>> +    .gem_prime_import = drm_gem_prime_import,
>> +    .gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
>> +    .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,
>> +    .enable_vblank = ltdc_crtc_enable_vblank,
>> +    .disable_vblank = ltdc_crtc_disable_vblank,
>> +};
>> +
>> +static int drv_load(struct drm_device *ddev)
>> +{
>> +    struct platform_device *pdev = to_platform_device(ddev->dev);
>> +    struct drm_fbdev_cma *fbdev;
>> +    struct stm_private *priv;
>> +    int ret;
>> +
>> +    DRM_DEBUG("%s\n", __func__);
>> +
>> +    priv = devm_kzalloc(ddev->dev, sizeof(*priv), GFP_KERNEL);
>> +    if (!priv)
>> +            return -ENOMEM;
>> +
>> +    ddev->dev_private = (void *)priv;
>> +
>> +    drm_mode_config_init(ddev);
>> +
>> +    /*
>> +     * set max width and height as default value.
>> +     * this value would be used to check framebuffer size limitation
>> +     * at drm_mode_addfb().
>> +     */
>> +    ddev->mode_config.min_width = 0;
>> +    ddev->mode_config.min_height = 0;
>> +    ddev->mode_config.max_width = STM_MAX_FB_WIDTH;
>> +    ddev->mode_config.max_height = STM_MAX_FB_HEIGHT;
>> +    ddev->mode_config.funcs = &drv_mode_config_funcs;
>> +
>> +    ret = ltdc_load(ddev);
>> +    if (ret)
>> +            return ret;
>> +
>> +    drm_mode_config_reset(ddev);
>> +    drm_kms_helper_poll_init(ddev);
>> +
>> +    if (ddev->mode_config.num_connector) {
>> +            priv = ddev->dev_private;
>> +            fbdev = drm_fbdev_cma_init(ddev, 16,
>> +                                       ddev->mode_config.num_connector);
>> +            if (IS_ERR(fbdev)) {
>> +                    DRM_DEBUG("Warning: fails to create fbdev\n");
>> +                    fbdev = NULL;
>> +            }
>> +            priv->fbdev = fbdev;
>> +    }
>> +
>> +    platform_set_drvdata(pdev, priv);
>> +
>> +    return 0;
>> +}
>> +
>> +static void drv_unload(struct drm_device *ddev)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +
>> +    DRM_DEBUG("%s\n", __func__);
>> +
>> +    ltdc_unload(ddev);
>> +
>> +    if (priv->fbdev) {
>> +            drm_fbdev_cma_fini(priv->fbdev);
>> +            priv->fbdev = NULL;
>> +    }
>> +
>> +    drm_kms_helper_poll_fini(ddev);
>> +    drm_vblank_cleanup(ddev);
>> +    drm_mode_config_cleanup(ddev);
>> +}
>> +
>> +static int stm_drm_platform_probe(struct platform_device *pdev)
>> +{
>> +    struct device *dev = &pdev->dev;
>> +    struct drm_device *ddev;
>> +    int ret;
>> +
>> +    DRM_DEBUG("%s\n", __func__);
>> +
>> +    dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
>> +
>> +    ddev = drm_dev_alloc(&drv_driver, dev);
>> +    if (IS_ERR(ddev))
>> +            return PTR_ERR(ddev);
>> +
>> +    ret = drv_load(ddev);
>> +    if (ret)
>> +            goto err_unref;
>> +
>> +    ret = drm_dev_register(ddev, 0);
>> +    if (ret)
>> +            goto err_unref;
>> +
>> +    return 0;
>> +
>> +err_unref:
>> +    drm_dev_unref(ddev);
>> +
>> +    return ret;
>> +}
>> +
>> +static int stm_drm_platform_remove(struct platform_device *pdev)
>> +{
>> +    struct drm_device *ddev = platform_get_drvdata(pdev);
>> +
>> +    DRM_DEBUG("%s\n", __func__);
>> +
>> +    drm_dev_unregister(ddev);
>> +    drv_unload(ddev);
>> +    drm_dev_unref(ddev);
>> +
>> +    return 0;
>> +}
>> +
>> +static const struct of_device_id drv_dt_ids[] = {
>> +    { .compatible = "st,stm32-ltdc"},
>> +    { /* end node */ },
>> +};
>> +MODULE_DEVICE_TABLE(of, drv_dt_ids);
>> +
>> +static struct platform_driver stm_drm_platform_driver = {
>> +    .probe = stm_drm_platform_probe,
>> +    .remove = stm_drm_platform_remove,
>> +    .driver = {
>> +            .name = DRIVER_NAME,
>> +            .of_match_table = drv_dt_ids,
>> +    },
>> +};
>> +
>> +module_platform_driver(stm_drm_platform_driver);
>> +
>> +MODULE_AUTHOR("Philippe Cornu <philippe.co...@st.com>");
>> +MODULE_AUTHOR("Yannick Fertre <yannick.fer...@st.com>");
>> +MODULE_AUTHOR("Fabien Dessenne <fabien.desse...@st.com>");
>> +MODULE_AUTHOR("Mickael Reulier <mickael.reul...@st.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/gpu/drm/stm/drv.h b/drivers/gpu/drm/stm/drv.h
>> new file mode 100644
>> index 0000000..edff073
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/drv.h
>> @@ -0,0 +1,22 @@
>> +/*
>> + * Copyright (C) STMicroelectronics SA 2017
>> + *
>> + * Authors: Philippe Cornu <philippe.co...@st.com>
>> + *          Yannick Fertre <yannick.fer...@st.com>
>> + *          Fabien Dessenne <fabien.desse...@st.com>
>> + *          Mickael Reulier <mickael.reul...@st.com>
>> + *
>> + * License terms:  GNU General Public License (GPL), version 2
>> + */
>> +
>> +#ifndef _DRV_H_
>> +#define _DRV_H_
>> +
>> +#include <drm/drmP.h>
>> +
>> +struct stm_private {
>> +    struct ltdc *ltdc;
>> +    struct drm_fbdev_cma *fbdev;
>> +};
>> +
>
> Any reason not to just put the fbdev in ltdc and drop this struct?
Ok. Done
>
>> +#endif
>> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
>> new file mode 100644
>> index 0000000..560375d
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/ltdc.c
>> @@ -0,0 +1,1422 @@
>> +/*
>> + * Copyright (C) STMicroelectronics SA 2017
>> + *
>> + * Authors: Philippe Cornu <philippe.co...@st.com>
>> + *          Yannick Fertre <yannick.fer...@st.com>
>> + *          Fabien Dessenne <fabien.desse...@st.com>
>> + *          Mickael Reulier <mickael.reul...@st.com>
>> + *
>> + * License terms:  GNU General Public License (GPL), version 2
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/component.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_graph.h>
>> +#include <linux/reset.h>
>> +
>> +#include <drm/drm_atomic.h>
>> +#include <drm/drm_atomic_helper.h>
>> +#include <drm/drm_crtc_helper.h>
>> +#include <drm/drm_fb_cma_helper.h>
>> +#include <drm/drm_gem_cma_helper.h>
>> +#include <drm/drm_of.h>
>> +#include <drm/drm_panel.h>
>> +#include <drm/drm_plane_helper.h>
>> +
>> +#include <video/videomode.h>
>> +
>> +#include "drv.h"
>> +#include "ltdc.h"
>> +
>> +#define NB_CRTC 1
>> +#define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
>> +
>> +#define MAX_IRQ 4
>> +
>> +#define HWVER_10200 0x010200
>> +#define HWVER_10300 0x010300
>> +#define HWVER_20101 0x020101
>> +
>> +/*
>> + * The address of some registers depends on the HW version: such registers 
>> have
>> + * an extra offset specified with reg_ofs.
>> + */
>> +#define REG_OFS_NONE        0
>> +#define REG_OFS_4   4 /* Insertion of "Layer Configuration 2" reg */
>> +#define REG_OFS             (ltdc->caps.reg_ofs)
>> +#define LAY_OFS             0x80    /* Register Offset between 2 layers */
>> +
>> +/* Global register offsets */
>> +#define LTDC_IDR    0x0000 /* IDentification */
>> +#define LTDC_LCR    0x0004 /* Layer Count */
>> +#define LTDC_SSCR   0x0008 /* Synchronization Size Configuration */
>> +#define LTDC_BPCR   0x000C /* Back Porch Configuration */
>> +#define LTDC_AWCR   0x0010 /* Active Width Configuration */
>> +#define LTDC_TWCR   0x0014 /* Total Width Configuration */
>> +#define LTDC_GCR    0x0018 /* Global Control */
>> +#define LTDC_GC1R   0x001C /* Global Configuration 1 */
>> +#define LTDC_GC2R   0x0020 /* Global Configuration 2 */
>> +#define LTDC_SRCR   0x0024 /* Shadow Reload Configuration */
>> +#define LTDC_GACR   0x0028 /* GAmma Correction */
>> +#define LTDC_BCCR   0x002C /* Background Color Configuration */
>> +#define LTDC_IER    0x0034 /* Interrupt Enable */
>> +#define LTDC_ISR    0x0038 /* Interrupt Status */
>> +#define LTDC_ICR    0x003C /* Interrupt Clear */
>> +#define LTDC_LIPCR  0x0040 /* Line Interrupt Position Configuration */
>> +#define LTDC_CPSR   0x0044 /* Current Position Status */
>> +#define LTDC_CDSR   0x0048 /* Current Display Status */
>> +
>> +/* Layer register offsets */
>> +#define LTDC_L1LC1R (0x0080)           /* L1 Layer Configuration 1 */
>> +#define LTDC_L1LC2R (0x0084)           /* L1 Layer Configuration 2 */
>> +#define LTDC_L1CR   (0x0084 + REG_OFS) /* L1 Control */
>> +#define LTDC_L1WHPCR        (0x0088 + REG_OFS) /* L1 Window Hor Position 
>> Config */
>> +#define LTDC_L1WVPCR        (0x008C + REG_OFS) /* L1 Window Vert Position 
>> Config */
>> +#define LTDC_L1CKCR (0x0090 + REG_OFS) /* L1 Color Keying Configuration */
>> +#define LTDC_L1PFCR (0x0094 + REG_OFS) /* L1 Pixel Format Configuration */
>> +#define LTDC_L1CACR (0x0098 + REG_OFS) /* L1 Constant Alpha Config */
>> +#define LTDC_L1DCCR (0x009C + REG_OFS) /* L1 Default Color Configuration */
>> +#define LTDC_L1BFCR (0x00A0 + REG_OFS) /* L1 Blend Factors Configuration */
>> +#define LTDC_L1FBBCR        (0x00A4 + REG_OFS) /* L1 FrameBuffer Bus 
>> Control */
>> +#define LTDC_L1AFBCR        (0x00A8 + REG_OFS) /* L1 AuxFB Control */
>> +#define LTDC_L1CFBAR        (0x00AC + REG_OFS) /* L1 Color FrameBuffer 
>> Address */
>> +#define LTDC_L1CFBLR        (0x00B0 + REG_OFS) /* L1 Color FrameBuffer 
>> Length */
>> +#define LTDC_L1CFBLNR       (0x00B4 + REG_OFS) /* L1 Color FrameBuffer Line 
>> Nb */
>> +#define LTDC_L1AFBAR        (0x00B8 + REG_OFS) /* L1 AuxFB Address */
>> +#define LTDC_L1AFBLR        (0x00BC + REG_OFS) /* L1 AuxFB Length */
>> +#define LTDC_L1AFBLNR       (0x00C0 + REG_OFS) /* L1 AuxFB Line Number */
>> +#define LTDC_L1CLUTWR       (0x00C4 + REG_OFS) /* L1 CLUT Write */
>> +#define LTDC_L1YS1R (0x00E0 + REG_OFS) /* L1 YCbCr Scale 1 */
>> +#define LTDC_L1YS2R (0x00E4 + REG_OFS) /* L1 YCbCr Scale 2 */
>> +
>> +/* Bit definitions */
>> +#define SSCR_VSH    GENMASK(10, 0)  /* Vertical Synchronization Height */
>> +#define SSCR_HSW    GENMASK(27, 16) /* Horizontal Synchronization Width */
>> +
>> +#define BPCR_AVBP   GENMASK(10, 0)  /* Accumulated Vertical Back Porch */
>> +#define BPCR_AHBP   GENMASK(27, 16) /* Accumulated Horizontal Back Porch */
>> +
>> +#define AWCR_AAH    GENMASK(10, 0)  /* Accumulated Active Height */
>> +#define AWCR_AAW    GENMASK(27, 16) /* Accumulated Active Width */
>> +
>> +#define TWCR_TOTALH GENMASK(10, 0)  /* TOTAL Height */
>> +#define TWCR_TOTALW GENMASK(27, 16) /* TOTAL Width */
>> +
>> +#define GCR_LTDCEN  BIT(0)          /* LTDC ENable */
>> +#define GCR_DEN             BIT(16)         /* Dither ENable */
>> +#define GCR_PCPOL   BIT(28)         /* Pixel Clock POLarity */
>> +#define GCR_DEPOL   BIT(29)         /* Data Enable POLarity */
>> +#define GCR_VSPOL   BIT(30)         /* Vertical Synchro POLarity */
>> +#define GCR_HSPOL   BIT(31)         /* Horizontal Synchro POLarity */
>> +
>> +#define GC1R_WBCH   GENMASK(3, 0)   /* Width of Blue CHannel output */
>> +#define GC1R_WGCH   GENMASK(7, 4)   /* Width of Green Channel output */
>> +#define GC1R_WRCH   GENMASK(11, 8)  /* Width of Red Channel output */
>> +#define GC1R_PBEN   BIT(12)         /* Precise Blending ENable */
>> +#define GC1R_DT             GENMASK(15, 14) /* Dithering Technique */
>> +#define GC1R_GCT    GENMASK(19, 17) /* Gamma Correction Technique */
>> +#define GC1R_SHREN  BIT(21)         /* SHadow Registers ENabled */
>> +#define GC1R_BCP    BIT(22)         /* Background Colour Programmable */
>> +#define GC1R_BBEN   BIT(23)         /* Background Blending ENabled */
>> +#define GC1R_LNIP   BIT(24)         /* Line Number IRQ Position */
>> +#define GC1R_TP             BIT(25)         /* Timing Programmable */
>> +#define GC1R_IPP    BIT(26)         /* IRQ Polarity Programmable */
>> +#define GC1R_SPP    BIT(27)         /* Sync Polarity Programmable */
>> +#define GC1R_DWP    BIT(28)         /* Dither Width Programmable */
>> +#define GC1R_STREN  BIT(29)         /* STatus Registers ENabled */
>> +#define GC1R_BMEN   BIT(31)         /* Blind Mode ENabled */
>> +
>> +#define GC2R_EDCA   BIT(0)          /* External Display Control Ability  */
>> +#define GC2R_STSAEN BIT(1)          /* Slave Timing Sync Ability ENabled */
>> +#define GC2R_DVAEN  BIT(2)          /* Dual-View Ability ENabled */
>> +#define GC2R_DPAEN  BIT(3)          /* Dual-Port Ability ENabled */
>> +#define GC2R_BW             GENMASK(6, 4)   /* Bus Width (log2 of nb of 
>> bytes) */
>> +#define GC2R_EDCEN  BIT(7)          /* External Display Control ENabled */
>> +
>> +#define SRCR_IMR    BIT(0)          /* IMmediate Reload */
>> +#define SRCR_VBR    BIT(1)          /* Vertical Blanking Reload */
>> +
>> +#define BCCR_BCBLACK        0x00            /* Background Color BLACK */
>> +#define BCCR_BCBLUE GENMASK(7, 0)   /* Background Color BLUE */
>> +#define BCCR_BCGREEN        GENMASK(15, 8)  /* Background Color GREEN */
>> +#define BCCR_BCRED  GENMASK(23, 16) /* Background Color RED */
>> +#define BCCR_BCWHITE        GENMASK(23, 0)  /* Background Color WHITE */
>> +
>> +#define IER_LIE             BIT(0)          /* Line Interrupt Enable */
>> +#define IER_FUIE    BIT(1)          /* Fifo Underrun Interrupt Enable */
>> +#define IER_TERRIE  BIT(2)          /* Transfer ERRor Interrupt Enable */
>> +#define IER_RRIE    BIT(3)          /* Register Reload Interrupt enable */
>> +
>> +#define ISR_LIF             BIT(0)          /* Line Interrupt Flag */
>> +#define ISR_FUIF    BIT(1)          /* Fifo Underrun Interrupt Flag */
>> +#define ISR_TERRIF  BIT(2)          /* Transfer ERRor Interrupt Flag */
>> +#define ISR_RRIF    BIT(3)          /* Register Reload Interrupt Flag */
>> +
>> +#define LXCR_LEN    BIT(0)          /* Layer ENable */
>> +#define LXCR_COLKEN BIT(1)          /* Color Keying Enable */
>> +#define LXCR_CLUTEN BIT(4)          /* Color Look-Up Table ENable */
>> +
>> +#define LXWHPCR_WHSTPOS     GENMASK(11, 0)  /* Window Horizontal StarT 
>> POSition */
>> +#define LXWHPCR_WHSPPOS     GENMASK(27, 16) /* Window Horizontal StoP 
>> POSition */
>> +
>> +#define LXWVPCR_WVSTPOS     GENMASK(10, 0)  /* Window Vertical StarT 
>> POSition */
>> +#define LXWVPCR_WVSPPOS     GENMASK(26, 16) /* Window Vertical StoP 
>> POSition */
>> +
>> +#define LXPFCR_PF   GENMASK(2, 0)   /* Pixel Format */
>> +
>> +#define LXCACR_CONSTA       GENMASK(7, 0)   /* CONSTant Alpha */
>> +
>> +#define LXBFCR_BF2  GENMASK(2, 0)   /* Blending Factor 2 */
>> +#define LXBFCR_BF1  GENMASK(10, 8)  /* Blending Factor 1 */
>> +
>> +#define LXCFBLR_CFBLL       GENMASK(12, 0)  /* Color Frame Buffer Line 
>> Length */
>> +#define LXCFBLR_CFBP        GENMASK(28, 16) /* Color Frame Buffer Pitch in 
>> bytes */
>> +
>> +#define LXCFBLNR_CFBLN      GENMASK(10, 0)   /* Color Frame Buffer Line 
>> Number */
>> +
>> +#define HSPOL_AL   0                /* Horizontal Sync POLarity Active Low 
>> */
>> +#define VSPOL_AL   0                /* Vertical Sync POLarity Active Low */
>> +#define DEPOL_AL   0                /* Data Enable POLarity Active Low */
>> +#define PCPOL_IPC  0                /* Input Pixel Clock */
>> +#define HSPOL_AH   GCR_HSPOL        /* Horizontal Sync POLarity Active High 
>> */
>> +#define VSPOL_AH   GCR_VSPOL        /* Vertical Sync POLarity Active High */
>> +#define DEPOL_AH   GCR_DEPOL        /* Data Enable POLarity Active High */
>> +#define PCPOL_IIPC GCR_PCPOL        /* Inverted Input Pixel Clock */
>> +#define CONSTA_MAX 0xFF             /* CONSTant Alpha MAX= 1.0 */
>> +#define BF1_PAXCA  0x600    /* Pixel Alpha x Constant Alpha */
>> +#define BF1_CA     0x400    /* Constant Alpha */
>> +#define BF2_1PAXCA 0x007    /* 1 - (Pixel Alpha x Constant Alpha) */
>> +#define BF2_1CA        0x005        /* 1 - Constant Alpha */
>> +
>> +enum ltdc_pix_fmt {
>> +    PF_NONE,
>> +    /* RGB formats */
>> +    PF_ARGB8888,    /* ARGB [32 bits] */
>> +    PF_RGBA8888,    /* RGBA [32 bits] */
>> +    PF_RGB888,      /* RGB [24 bits] */
>> +    PF_RGB565,      /* RGB [16 bits] */
>> +    PF_ARGB1555,    /* ARGB A:1 bit RGB:15 bits [16 bits] */
>> +    PF_ARGB4444,    /* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
>> +    /* Indexed formats */
>> +    PF_L8,          /* Indexed 8 bits [8 bits] */
>> +    PF_AL44,        /* Alpha:4 bits + indexed 4 bits [8 bits] */
>> +    PF_AL88         /* Alpha:8 bits + indexed 8 bits [16 bits] */
>> +};
>> +
>> +#define NB_PF           8       /* Max nb of HW pixel format */
>> +
>> +/* The index gives the encoding of the pixel format for an HW version */
>> +static const enum ltdc_pix_fmt ltdc_pix_fmt_a0[NB_PF] = {
>> +    PF_ARGB8888,    /* 0x00 */
>> +    PF_RGB888,      /* 0x01 */
>> +    PF_RGB565,      /* 0x02 */
>> +    PF_ARGB1555,    /* 0x03 */
>> +    PF_ARGB4444,    /* 0x04 */
>> +    PF_L8,          /* 0x05 */
>> +    PF_AL44,        /* 0x06 */
>> +    PF_AL88         /* 0x07 */
>> +};
>> +
>> +static const enum ltdc_pix_fmt ltdc_pix_fmt_a1[NB_PF] = {
>> +    PF_ARGB8888,    /* 0x00 */
>> +    PF_RGB888,      /* 0x01 */
>> +    PF_RGB565,      /* 0x02 */
>> +    PF_RGBA8888,    /* 0x03 */
>> +    PF_AL44,        /* 0x04 */
>> +    PF_L8,          /* 0x05 */
>> +    PF_ARGB1555,    /* 0x06 */
>> +    PF_ARGB4444     /* 0x07 */
>> +};
>> +
>> +struct ltdc_caps {
>> +    u32 hw_version;         /* hardware version */
>> +    u32 nb_layers;          /* number of supported layers */
>> +    u32 reg_ofs;            /* register offset for applicable regs */
>> +    u32 bus_width;          /* bus width (32 or 64 bits) */
>> +    const enum ltdc_pix_fmt *pix_fmt_hw; /* supported pixel formats */
>> +};
>> +
>> +struct ltdc {
>> +    struct drm_device *ddev;
>> +    void __iomem *regs;
>> +    struct clk *pixel_clk;  /* lcd pixel clock */
>> +    struct drm_panel *panel;
>> +    struct drm_pending_vblank_event *pending_event;
>> +    u32 irq_status;
>> +    u32 error_status;
>> +    struct mutex err_lock;  /* protecting error_status */
>> +    struct ltdc_caps caps;
>> +    u32 clut[256];          /* color look up table */
>> +};
>> +
>> +static inline u32 reg_read(void __iomem *base, u32 reg)
>> +{
>> +    return readl_relaxed(base + reg);
>> +}
>> +
>> +static inline void reg_write(void __iomem *base, u32 reg, u32 val)
>> +{
>> +    writel_relaxed(val, base + reg);
>> +}
>> +
>> +static inline void reg_set(void __iomem *base, u32 reg, u32 mask)
>> +{
>> +    reg_write(base, reg, reg_read(base, reg) | mask);
>> +}
>> +
>> +static inline void reg_clear(void __iomem *base, u32 reg, u32 mask)
>> +{
>> +    reg_write(base, reg, reg_read(base, reg) & ~mask);
>> +}
>> +
>> +static inline void reg_update_bits(void __iomem *base, u32 reg, u32 mask,
>> +                               u32 val)
>> +{
>> +    reg_write(base, reg, (reg_read(base, reg) & ~mask) | val);
>> +}
>> +
>> +static inline struct ltdc *crtc_to_ltdc(struct drm_crtc *crtc)
>> +{
>> +    return ((struct stm_private *)crtc->dev->dev_private)->ltdc;
>> +}
>> +
>> +static inline struct ltdc *plane_to_ltdc(struct drm_plane *plane)
>> +{
>> +    return ((struct stm_private *)plane->dev->dev_private)->ltdc;
>> +}
>> +
>> +static inline struct ltdc *encoder_to_ltdc(struct drm_encoder *encoder)
>> +{
>> +    return ((struct stm_private *)encoder->dev->dev_private)->ltdc;
>> +}
>> +
>> +static inline struct ltdc *connector_to_ltdc(struct drm_connector 
>> *connector)
>> +{
>> +    return ((struct stm_private *)connector->dev->dev_private)->ltdc;
>> +}
>> +
>> +static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
>> +{
>> +    enum ltdc_pix_fmt pf;
>> +
>> +    switch (drm_fmt) {
>> +    case DRM_FORMAT_ARGB8888:
>> +    case DRM_FORMAT_XRGB8888:
>> +            pf = PF_ARGB8888;
>> +            break;
>> +    case DRM_FORMAT_RGBA8888:
>> +    case DRM_FORMAT_RGBX8888:
>> +            pf = PF_RGBA8888;
>> +            break;
>> +    case DRM_FORMAT_RGB888:
>> +            pf = PF_RGB888;
>> +            break;
>> +    case DRM_FORMAT_RGB565:
>> +            pf = PF_RGB565;
>> +            break;
>> +    case DRM_FORMAT_ARGB1555:
>> +    case DRM_FORMAT_XRGB1555:
>> +            pf = PF_ARGB1555;
>> +            break;
>> +    case DRM_FORMAT_ARGB4444:
>> +    case DRM_FORMAT_XRGB4444:
>> +            pf = PF_ARGB4444;
>> +            break;
>> +    case DRM_FORMAT_C8:
>> +            pf = PF_L8;
>> +            break;
>> +    default:
>> +            pf = PF_NONE;
>> +            break;
>> +    /* Note: There are no DRM_FORMAT for AL44 and AL88 */
>> +    }
>> +
>> +    return pf;
>> +}
>> +
>> +static inline u32 to_drm_pixelformat(enum ltdc_pix_fmt pf)
>> +{
>> +    switch (pf) {
>> +    case PF_ARGB8888:
>> +            return DRM_FORMAT_ARGB8888;
>> +    case PF_RGBA8888:
>> +            return DRM_FORMAT_RGBA8888;
>> +    case PF_RGB888:
>> +            return DRM_FORMAT_RGB888;
>> +    case PF_RGB565:
>> +            return DRM_FORMAT_RGB565;
>> +    case PF_ARGB1555:
>> +            return DRM_FORMAT_ARGB1555;
>> +    case PF_ARGB4444:
>> +            return DRM_FORMAT_ARGB4444;
>> +    case PF_L8:
>> +            return DRM_FORMAT_C8;
>> +    case PF_AL44: /* No DRM support */
>> +    case PF_AL88: /* No DRM support */
>> +    case PF_NONE:
>> +    default:
>> +            return 0;
>> +    }
>> +}
>> +
>> +static struct drm_crtc *crtc_from_pipe(struct drm_device *ddev,
>> +                                   unsigned int pipe)
>> +{
>> +    struct drm_crtc *crtc;
>> +
>> +    list_for_each_entry(crtc, &ddev->mode_config.crtc_list, head) {
>> +            if (pipe == drm_crtc_index(crtc))
>> +                    return crtc;
>> +    }
>> +
>> +    return NULL;
>> +}
>
> This looks like a duplicate of drm_crtc_from_index().
Ok. Done
>
>> +static irqreturn_t ltdc_irq_thread(int irq, void *arg)
>> +{
>> +    struct ltdc *ltdc = arg;
>> +    struct drm_crtc *crtc = crtc_from_pipe(ltdc->ddev, 0);
>> +
>> +    /* Line IRQ : trigger the vblank event */
>> +    if (ltdc->irq_status & ISR_LIF)
>> +            drm_crtc_handle_vblank(crtc);
>> +
>> +    /* Save FIFO Underrun & Transfer Error status */
>> +    mutex_lock(&ltdc->err_lock);
>> +    if (ltdc->irq_status & ISR_FUIF)
>> +            ltdc->error_status |= ISR_FUIF;
>> +    if (ltdc->irq_status & ISR_TERRIF)
>> +            ltdc->error_status |= ISR_TERRIF;
>> +    mutex_unlock(&ltdc->err_lock);
>> +
>> +    return IRQ_HANDLED;
>> +}
>> +
>> +static irqreturn_t ltdc_irq(int irq, void *arg)
>> +{
>> +    struct ltdc *ltdc = arg;
>> +
>> +    /* Read & Clear the interrupt status */
>> +    ltdc->irq_status = reg_read(ltdc->regs, LTDC_ISR);
>> +    reg_write(ltdc->regs, LTDC_ICR, ltdc->irq_status);
>> +
>> +    return IRQ_WAKE_THREAD;
>> +}
>
> I'm curious, why a threaded irq here?  Can't you just use a spinlock for
> err_lock and then move the thread body in here?
STM32F4 is MCU with a slow CPU frequency. To avoid to overload irq, I 
use a thread to manage vblanck handling.

>
>> +/*
>> + * DRM_CRTC
>> + */
>> +
>> +static void ltdc_crtc_load_lut(struct drm_crtc *crtc)
>> +{
>> +    struct ltdc *ltdc = crtc_to_ltdc(crtc);
>> +    unsigned int i, lay;
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    for (lay = 0; lay < ltdc->caps.nb_layers; lay++)
>> +            for (i = 0; i < 256; i++)
>> +                    reg_write(ltdc->regs, LTDC_L1CLUTWR + lay * LAY_OFS,
>> +                              ltdc->clut[i]);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +}
>> +
>> +static void ltdc_crtc_enable(struct drm_crtc *crtc)
>> +{
>> +    struct ltdc *ltdc = crtc_to_ltdc(crtc);
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    /* Sets the background color value */
>> +    reg_write(ltdc->regs, LTDC_BCCR, BCCR_BCBLACK);
>> +
>> +    /* Enable IRQ */
>> +    reg_set(ltdc->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
>> +
>> +    /* Immediately commit the planes */
>> +    reg_set(ltdc->regs, LTDC_SRCR, SRCR_IMR);
>> +
>> +    /* Enable LTDC */
>> +    reg_set(ltdc->regs, LTDC_GCR, GCR_LTDCEN);
>> +
>> +    drm_crtc_vblank_on(crtc);
>> +}
>> +
>> +static void ltdc_crtc_disable(struct drm_crtc *crtc)
>> +{
>> +    struct ltdc *ltdc = crtc_to_ltdc(crtc);
>> +    unsigned int i;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (!crtc->enabled) {
>> +            DRM_DEBUG_DRIVER("already disabled\n");
>> +            return;
>> +    }
>> +
>> +    drm_crtc_vblank_off(crtc);
>> +
>> +    /* disable LTDC */
>> +    reg_clear(ltdc->regs, LTDC_GCR, GCR_LTDCEN);
>> +
>> +    /* disable IRQ */
>> +    reg_clear(ltdc->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
>> +
>> +    /* disable layers */
>> +    for (i = 0; i < ltdc->caps.nb_layers; i++)
>> +            reg_clear(ltdc->regs, LTDC_L1CR + i * LAY_OFS, LXCR_LEN);
>
> I think you're guaranteed that the layers have been disable()d.
Ok. Done
>
>> +    /* immediately commit disable of layers before switching off LTDC */
>> +    reg_set(ltdc->regs, LTDC_SRCR, SRCR_IMR);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +
>> +    if (crtc->state->event && !crtc->state->active) {
>> +            spin_lock_irq(&crtc->dev->event_lock);
>> +            drm_crtc_send_vblank_event(crtc, crtc->state->event);
>> +            spin_unlock_irq(&crtc->dev->event_lock);
>> +
>> +            crtc->state->event = NULL;
>> +    }
>
> Instead of this block here, on pl111 I just made the "if
> (drm_crtc_vblank_get(crtc) == 0)" in the CRTC atomic_flush() also check
> for crtc->state->active before starting to arm.
>
>> +}
>> +
>> +static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
>> +                             const struct drm_display_mode *mode,
>> +                             struct drm_display_mode *adjusted_mode)
>> +{
>> +    DRM_DEBUG_DRIVER("\n");
>> +    /* accept the provided drm_display_mode, do not fix it up */
>> +
>> +    return true;
>> +}
>
> If you don't do anything in this function, it can be dropped.
>
Ok Done
>> +static u32 ltdc_get_paddr(struct drm_framebuffer *fb, int x, int y)
>> +{
>> +    struct drm_gem_cma_object *cma_obj;
>> +    unsigned int pixsize;
>> +    u32 paddr;
>> +
>> +    cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
>> +    if (IS_ERR(cma_obj)) {
>> +            DRM_ERROR("Can't get CMA GEM object for fb\n");
>> +            return 0;
>> +    }
>> +
>> +    pixsize = drm_format_plane_cpp(fb->format->format, 0);
>> +    paddr = (u32)cma_obj->paddr + fb->offsets[0];
>> +    paddr += (x * pixsize) + (y * fb->pitches[0]);
>> +
>> +    return paddr;
>> +}
>
> Having just written this function for pl111, one of us should probably
> put a generic copy in drm_fb_cma_helper.  No need to do so for getting
> your driver in, though.
Ok. I'll create a new function to return physical address in helpers.
>
>> +static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
>> +{
>> +    struct ltdc *ltdc = crtc_to_ltdc(crtc);
>> +    struct drm_display_mode *mode = &crtc->state->adjusted_mode;
>> +    struct videomode vm;
>> +    int rate = mode->clock * 1000;
>> +    u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
>> +    u32 total_width, total_height;
>> +    u32 val;
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    drm_display_mode_to_videomode(mode, &vm);
>> +
>> +    DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
>> +    DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
>> +    DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
>> +                     vm.hfront_porch, vm.hback_porch, vm.hsync_len,
>> +                     vm.vfront_porch, vm.vback_porch, vm.vsync_len);
>> +
>> +    /* Convert video timings to ltdc timings */
>> +    hsync = vm.hsync_len - 1;
>> +    vsync = vm.vsync_len - 1;
>> +    accum_hbp = hsync + vm.hback_porch;
>> +    accum_vbp = vsync + vm.vback_porch;
>> +    accum_act_w = accum_hbp + vm.hactive;
>> +    accum_act_h = accum_vbp + vm.vactive;
>> +    total_width = accum_act_w + vm.hfront_porch;
>> +    total_height = accum_act_h + vm.vfront_porch;
>> +
>> +    if (clk_set_rate(ltdc->pixel_clk, rate) < 0) {
>> +            DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
>> +            return;
>> +    }
>> +
>> +    /* Configures the HS, VS, DE and PC polarities. */
>> +    val = HSPOL_AL | HSPOL_AL | DEPOL_AL | PCPOL_IPC;
>> +
>> +    if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
>> +            val |= HSPOL_AH;
>> +
>> +    if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
>> +            val |= VSPOL_AH;
>> +
>> +    if (vm.flags & DISPLAY_FLAGS_DE_HIGH)
>> +            val |= DEPOL_AH;
>> +
>> +    if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
>> +            val |= PCPOL_IIPC;
>> +
>> +    reg_update_bits(ltdc->regs, LTDC_GCR,
>> +                    GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
>> +
>> +    /* Set Synchronization size */
>> +    val = (hsync << 16) | vsync;
>> +    reg_update_bits(ltdc->regs, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
>> +
>> +    /* Set Accumulated Back porch */
>> +    val = (accum_hbp << 16) | accum_vbp;
>> +    reg_update_bits(ltdc->regs, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
>> +
>> +    /* Set Accumulated Active Width */
>> +    val = (accum_act_w << 16) | accum_act_h;
>> +    reg_update_bits(ltdc->regs, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
>> +
>> +    /* Set total width & height */
>> +    val = (total_width << 16) | total_height;
>> +    reg_update_bits(ltdc->regs, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
>> +
>> +    reg_write(ltdc->regs, LTDC_LIPCR, (accum_act_h + 1));
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +}
>> +
>> +static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
>> +                               struct drm_crtc_state *old_crtc_state)
>> +{
>> +    struct ltdc *ltdc = crtc_to_ltdc(crtc);
>> +    struct drm_pending_vblank_event *event = crtc->state->event;
>> +
>> +    DRM_DEBUG_ATOMIC("\n");
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    /* Commit shadow registers = update planes at next vblank */
>> +    reg_set(ltdc->regs, LTDC_SRCR, SRCR_VBR);
>> +
>> +    if (event) {
>> +            crtc->state->event = NULL;
>> +
>> +            spin_lock_irq(&crtc->dev->event_lock);
>> +            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);
>> +    }
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +}
>> +
>> +static struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
>> +    .load_lut = ltdc_crtc_load_lut,
>> +    .enable = ltdc_crtc_enable,
>> +    .disable = ltdc_crtc_disable,
>> +    .mode_fixup = ltdc_crtc_mode_fixup,
>> +    .mode_set_nofb = ltdc_crtc_mode_set_nofb,
>> +    .atomic_flush = ltdc_crtc_atomic_flush,
>> +};
>> +
>> +int ltdc_crtc_enable_vblank(struct drm_device *ddev, unsigned int pipe)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +    struct ltdc *ltdc = priv->ltdc;
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return -EINVAL;
>> +    }
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +    reg_set(ltdc->regs, LTDC_IER, IER_LIE);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +
>> +    return 0;
>> +}
>> +
>> +void ltdc_crtc_disable_vblank(struct drm_device *ddev, unsigned int pipe)
>> +{
>> +    struct drm_crtc *crtc = crtc_from_pipe(ddev, pipe);
>> +    struct stm_private *priv = ddev->dev_private;
>> +    struct ltdc *ltdc = priv->ltdc;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    reg_clear(ltdc->regs, LTDC_IER, IER_LIE);
>> +
>> +    if (ltdc->pending_event) {
>> +            drm_crtc_vblank_put(crtc);
>> +            ltdc->pending_event = NULL;
>> +    }
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +}
> Note that instead of looking up the crtc from its index, you could move
> these hooks from the dev to the enable/disable_vblank in drm_crtc_funcs.
>
Ok, I remove this hook
>> +static struct drm_crtc_funcs ltdc_crtc_funcs = {
>> +    .destroy = drm_crtc_cleanup,
>> +    .set_config = drm_atomic_helper_set_config,
>> +    .page_flip = drm_atomic_helper_page_flip,
>> +    .reset = drm_atomic_helper_crtc_reset,
>> +    .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
>> +    .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
>> +};
>> +
>> +/*
>> + * DRM_PLANE
>> + */
>> +
>> +static int ltdc_plane_atomic_check(struct drm_plane *plane,
>> +                               struct drm_plane_state *state)
>> +{
>> +    struct drm_framebuffer *fb = state->fb;
>> +    u32 src_x, src_y, src_w, src_h;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (!fb)
>> +            return 0;
>> +
>> +    /* convert src_ from 16:16 format */
>> +    src_x = state->src_x >> 16;
>> +    src_y = state->src_y >> 16;
>> +    src_w = state->src_w >> 16;
>> +    src_h = state->src_h >> 16;
>> +
>> +    /* Reject scaling */
>> +    if ((src_w != state->crtc_w) || (src_h != state->crtc_h)) {
>> +            DRM_ERROR("Scaling is not supported");
>> +            return -EINVAL;
>> +    }
>> +
>> +    if (!ltdc_get_paddr(fb, src_x, src_y)) {
>> +            DRM_ERROR("Cannot get fb address\n");
>> +            return -EFAULT;
>> +    }
>
> I don't think this call can fail.
>
Ok, Done
>> +    return 0;
>> +}
>> +
>> +static void ltdc_plane_atomic_update(struct drm_plane *plane,
>> +                                 struct drm_plane_state *oldstate)
>> +{
>> +    struct ltdc *ltdc = plane_to_ltdc(plane);
>> +    struct drm_plane_state *state = plane->state;
>> +    struct drm_framebuffer *fb = state->fb;
>> +    u32 lofs = plane->index * LAY_OFS;
>> +    u32 x0 = state->crtc_x;
>> +    u32 x1 = state->crtc_x + state->crtc_w - 1;
>> +    u32 y0 = state->crtc_y;
>> +    u32 y1 = state->crtc_y + state->crtc_h - 1;
>> +    u32 src_x, src_y, src_w, src_h;
>> +    u32 val, pitch_in_bytes, line_length, paddr, ahbp, avbp, bpcr;
>> +    enum ltdc_pix_fmt pf;
>> +
>> +    if (!state->crtc || !fb) {
>> +            DRM_DEBUG_DRIVER("fb or crtc NULL");
>> +            return;
>> +    }
>> +
>> +    /* convert src_ from 16:16 format */
>> +    src_x = state->src_x >> 16;
>> +    src_y = state->src_y >> 16;
>> +    src_w = state->src_w >> 16;
>> +    src_h = state->src_h >> 16;
>> +
>> +    DRM_DEBUG_DRIVER(
>> +            "plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
>> +            plane->base.id, fb->base.id,
>> +            src_w, src_h, src_x, src_y,
>> +            state->crtc_w, state->crtc_h, state->crtc_x, state->crtc_y);
>> +
>> +    bpcr = reg_read(ltdc->regs, LTDC_BPCR);
>> +    ahbp = (bpcr & BPCR_AHBP) >> 16;
>> +    avbp = bpcr & BPCR_AVBP;
>> +
>> +    /* Configures the horizontal start and stop position */
>> +    val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
>> +    reg_update_bits(ltdc->regs, LTDC_L1WHPCR + lofs,
>> +                    LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
>> +
>> +    /* Configures the vertical start and stop position */
>> +    val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
>> +    reg_update_bits(ltdc->regs, LTDC_L1WVPCR + lofs,
>> +                    LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
>> +
>> +    /* Specifies the pixel format */
>> +    pf = to_ltdc_pixelformat(fb->format->format);
>> +    for (val = 0; val < NB_PF; val++)
>> +            if (ltdc->caps.pix_fmt_hw[val] == pf)
>> +                    break;
>> +
>> +    if (val == NB_PF) {
>> +            DRM_ERROR("Pixel format %.4s not supported\n",
>> +                      (char *)&fb->format->format);
>> +            val = 0; /* set by default ARGB 32 bits */
>> +    }
>> +    reg_update_bits(ltdc->regs, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
>> +
>> +    /* Configures the color frame buffer pitch in bytes & line length */
>> +    pitch_in_bytes = fb->pitches[0];
>> +    line_length = drm_format_plane_cpp(fb->format->format, 0) *
>> +                  (x1 - x0 + 1) + (ltdc->caps.bus_width >> 3) - 1;
>> +    val = ((pitch_in_bytes << 16) | line_length);
>> +    reg_update_bits(ltdc->regs, LTDC_L1CFBLR + lofs,
>> +                    LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
>> +
>> +    /* Specifies the constant alpha value */
>> +    val = CONSTA_MAX;
>> +    reg_update_bits(ltdc->regs, LTDC_L1CACR + lofs,
>> +                    LXCACR_CONSTA, val);
>> +
>> +    /* Specifies the blending factors */
>> +    val = BF1_PAXCA | BF2_1PAXCA;
>> +    reg_update_bits(ltdc->regs, LTDC_L1BFCR + lofs,
>> +                    LXBFCR_BF2 | LXBFCR_BF1, val);
>> +
>> +    /* Configures the frame buffer line number */
>> +    val = y1 - y0 + 1;
>> +    reg_update_bits(ltdc->regs, LTDC_L1CFBLNR + lofs,
>> +                    LXCFBLNR_CFBLN, val);
>> +
>> +    /* Sets the FB address */
>> +    paddr = ltdc_get_paddr(fb, src_x, src_y);
>> +    DRM_DEBUG_DRIVER("fb: phys 0x%08x", paddr);
>> +    reg_write(ltdc->regs, LTDC_L1CFBAR + lofs, paddr);
>> +
>> +    /* Enable layer and CLUT if needed */
>> +    val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
>> +    val |= LXCR_LEN;
>> +    reg_update_bits(ltdc->regs, LTDC_L1CR + lofs,
>> +                    LXCR_LEN | LXCR_CLUTEN, val);
>> +
>> +    mutex_lock(&ltdc->err_lock);
>> +    if (ltdc->error_status & ISR_FUIF) {
>> +            DRM_DEBUG_DRIVER("Fifo underrun\n");
>> +            ltdc->error_status &= ~ISR_FUIF;
>> +    }
>> +    if (ltdc->error_status & ISR_TERRIF) {
>> +            DRM_DEBUG_DRIVER("Transfer error\n");
>> +            ltdc->error_status &= ~ISR_TERRIF;
>> +    }
>> +    mutex_unlock(&ltdc->err_lock);
>> +}
>> +
>> +static void ltdc_plane_atomic_disable(struct drm_plane *plane,
>> +                                  struct drm_plane_state *oldstate)
>> +{
>> +    struct ltdc *ltdc = plane_to_ltdc(plane);
>> +    u32 lofs = plane->index * LAY_OFS;
>> +
>> +    if (!oldstate->crtc) {
>> +            DRM_DEBUG_DRIVER("drm plane:%d not enabled\n", plane->base.id);
>> +            return;
>> +    }
>
> I believe you're guaranteed that it was enabled when the disable is called.
>
Ok Done
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return;
>> +    }
>> +
>> +    /* disable layer */
>> +    reg_clear(ltdc->regs, LTDC_L1CR + lofs, LXCR_LEN);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +
>> +    DRM_DEBUG_DRIVER("CRTC:%d plane:%d\n",
>> +                     oldstate->crtc->base.id, plane->base.id);
>> +}
>> +
>> +static void ltdc_plane_destroy(struct drm_plane *plane)
>> +{
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    drm_plane_helper_disable(plane);
>> +    drm_plane_cleanup(plane);
>> +}
>
> Hmm.  I would assume that a plane has been disabled at the point that
> destroy is called, so that you wouldn't even need this wrapper function.
Ok, Done
>
>> +
>> +static struct drm_plane_funcs ltdc_plane_funcs = {
>> +    .update_plane = drm_atomic_helper_update_plane,
>> +    .disable_plane = drm_atomic_helper_disable_plane,
>> +    .destroy = ltdc_plane_destroy,
>> +    .set_property = drm_atomic_helper_plane_set_property,
>> +    .reset = drm_atomic_helper_plane_reset,
>> +    .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
>> +    .atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
>> +};
>> +
>> +static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
>> +    .atomic_check = ltdc_plane_atomic_check,
>> +    .atomic_update = ltdc_plane_atomic_update,
>> +    .atomic_disable = ltdc_plane_atomic_disable,
>> +};
>> +
>> +static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
>> +                                       enum drm_plane_type type)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +    unsigned long possible_crtcs = CRTC_MASK;
>> +    struct device *dev = ddev->dev;
>> +    struct ltdc *ltdc = priv->ltdc;
>> +    struct drm_plane *plane;
>> +    unsigned int i, nb_fmt = 0;
>> +    u32 formats[NB_PF];
>> +    u32 drm_fmt;
>> +    int ret;
>> +
>> +    /* Get supported pixel formats */
>> +    for (i = 0; i < NB_PF; i++) {
>> +            drm_fmt = to_drm_pixelformat(ltdc->caps.pix_fmt_hw[i]);
>> +            if (!drm_fmt)
>> +                    continue;
>> +            formats[nb_fmt++] = drm_fmt;
>> +    }
>> +
>> +    plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
>> +    if (!plane)
>> +            return 0;
>> +
>> +    ret = drm_universal_plane_init(ddev, plane, possible_crtcs,
>> +                                   &ltdc_plane_funcs, formats, nb_fmt,
>> +                                   type, NULL);
>> +    if (ret < 0)
>> +            return 0;
>> +
>> +    drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
>> +
>> +    DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
>> +
>> +    return plane;
>> +}
>> +
>> +static void ltdc_plane_destroy_all(struct ltdc *ltdc)
>> +{
>> +    struct drm_plane *plane, *plane_temp;
>> +
>> +    list_for_each_entry_safe(plane, plane_temp,
>> +                             &ltdc->ddev->mode_config.plane_list, head)
>> +            drm_plane_cleanup(plane);
>> +}
>> +
>> +static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +    struct ltdc *ltdc = priv->ltdc;
>> +    struct drm_plane *primary, *overlay;
>> +    unsigned int i;
>> +    int res;
>> +
>> +    primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY);
>> +    if (!primary) {
>> +            DRM_ERROR("Can not create primary plane\n");
>> +            return -EINVAL;
>> +    }
>> +
>> +    res = drm_crtc_init_with_planes(ddev, crtc, primary, NULL,
>> +                                    &ltdc_crtc_funcs, NULL);
>> +    if (res) {
>> +            DRM_ERROR("Can not initialize CRTC\n");
>> +            goto cleanup;
>> +    }
>> +
>> +    drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
>> +
>> +    DRM_DEBUG_DRIVER("CRTC:%d created\n", crtc->base.id);
>> +
>> +    /* Add planes. Note : the first layer is used by primary plane */
>> +    for (i = 1; i < ltdc->caps.nb_layers; i++) {
>> +            overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY);
>> +            if (!overlay) {
>> +                    res = -ENOMEM;
>> +                    DRM_ERROR("Can not create overlay plane %d\n", i);
>> +                    goto cleanup;
>> +            }
>> +    }
>> +
>> +    return 0;
>> +
>> +cleanup:
>> +    ltdc_plane_destroy_all(ltdc);
>> +    return res;
>> +}
>> +
>> +/*
>> + * DRM_ENCODER
>> + */
>> +
>> +static void ltdc_rgb_encoder_enable(struct drm_encoder *encoder)
>> +{
>> +    struct ltdc *ltdc = encoder_to_ltdc(encoder);
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    drm_panel_prepare(ltdc->panel);
>> +    drm_panel_enable(ltdc->panel);
>> +}
>> +
>> +static void ltdc_rgb_encoder_disable(struct drm_encoder *encoder)
>> +{
>> +    struct ltdc *ltdc = encoder_to_ltdc(encoder);
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    drm_panel_disable(ltdc->panel);
>> +    drm_panel_unprepare(ltdc->panel);
>> +}
>> +
>> +static const struct drm_encoder_helper_funcs ltdc_rgb_encoder_helper_funcs 
>> = {
>> +    .enable = ltdc_rgb_encoder_enable,
>> +    .disable = ltdc_rgb_encoder_disable,
>> +};
>> +
>> +static const struct drm_encoder_funcs ltdc_rgb_encoder_funcs = {
>> +    .destroy = drm_encoder_cleanup,
>> +};
>> +
>> +static struct drm_encoder *ltdc_rgb_encoder_create(struct drm_device *ddev)
>> +{
>> +    struct drm_encoder *encoder;
>> +
>> +    encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
>> +    if (!encoder)
>> +            return NULL;
>> +
>> +    encoder->possible_crtcs = CRTC_MASK;
>> +    encoder->possible_clones = 0; /* No cloning support */
>> +
>> +    drm_encoder_init(ddev, encoder, &ltdc_rgb_encoder_funcs,
>> +                     DRM_MODE_ENCODER_LVDS, NULL);
>> +
>> +    drm_encoder_helper_add(encoder, &ltdc_rgb_encoder_helper_funcs);
>> +
>> +    DRM_DEBUG_DRIVER("RGB encoder:%d created\n", encoder->base.id);
>> +
>> +    return encoder;
>> +}
>> +
>> +static struct drm_encoder *ltdc_rgb_encoder_find(struct drm_device *ddev)
>> +{
>> +    struct drm_encoder *encoder;
>> +
>> +    list_for_each_entry(encoder, &ddev->mode_config.encoder_list, head) {
>> +            if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
>> +                    return encoder;
>> +    }
>> +
>> +    return NULL;
>> +}
>> +
>> +static int ltdc_create_encoders(struct ltdc *ltdc)
>> +{
>> +    struct drm_device *ddev = ltdc->ddev;
>> +    struct drm_encoder *encoder;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (ltdc->panel) {
>> +            encoder = ltdc_rgb_encoder_create(ddev);
>> +            if (!encoder)
>> +                    return -EINVAL;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void ltdc_destroy_encoders(struct ltdc *ltdc)
>> +{
>> +    struct drm_encoder *encoder, *encoder_temp;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    list_for_each_entry_safe(encoder, encoder_temp,
>> +                             &ltdc->ddev->mode_config.encoder_list, head)
>> +            drm_encoder_cleanup(encoder);
>> +}
>> +
>> +/*
>> + * DRM_CONNECTOR
>> + */
>> +
>> +static int ltdc_rgb_connector_get_modes(struct drm_connector *connector)
>> +{
>> +    struct ltdc *ltdc = connector_to_ltdc(connector);
>> +    int ret = 0;
>> +
>> +    dev_dbg(ltdc->ddev->dev, "%s\n", __func__);
>> +
>> +    if (ltdc->panel)
>> +            ret = drm_panel_get_modes(ltdc->panel);
>> +
>> +    return ret < 0 ? 0 : ret;
>> +}
>> +
>> +/* Set a tolerance of 20% on pixel clock */
>> +#define CLK_TOLERANCE_PCT 20
>> +
>> +static enum drm_mode_status
>> +ltdc_rgb_connector_mode_valid(struct drm_connector *connector,
>> +                          struct drm_display_mode *mode)
>> +{
>> +    struct ltdc *ltdc = connector_to_ltdc(connector);
>> +    unsigned long rate = mode->clock * 1000;
>> +    long rate_min = rate - (rate * CLK_TOLERANCE_PCT) / 100;
>> +    long rate_max = rate;
>> +    long rounded_rate;
>> +
>> +    rounded_rate = clk_round_rate(ltdc->pixel_clk, rate);
>> +
>> +    DRM_DEBUG_DRIVER("Target rate = %ld => available rate = %ld\n",
>> +                     rate, rounded_rate);
>> +
>> +    if (rounded_rate < rate_min)
>> +            return MODE_CLOCK_LOW;
>> +
>> +    if (rounded_rate > rate_max)
>> +            return MODE_CLOCK_HIGH;
>> +
>> +    if (!rate)
>> +            return MODE_BAD;
>> +
>> +    return MODE_OK;
>> +}
>
> I like that you've got a tolerance on your clocks here.
>
> Something interesting that I read recently: mode_valid doesn't actually
> limit whether userspace can set a mode on the hw, it just filters modes
> coming back from your get_modes().  Unless the core starts doing this,
> you might be interested in calling this function from the CRTC's
> mode_fixup().
>
Ok, there 's no real constraints on clock. I prefers to remove this part.

>> +static struct drm_connector_helper_funcs ltdc_rgb_connector_helper_funcs = {
>> +    .get_modes = ltdc_rgb_connector_get_modes,
>> +    .mode_valid = ltdc_rgb_connector_mode_valid,
>> +};
>> +
>> +static enum drm_connector_status
>> +ltdc_rgb_connector_detect(struct drm_connector *connector, bool force)
>> +{
>> +    struct ltdc *ltdc = connector_to_ltdc(connector);
>> +    int ret = 0;
>> +
>> +    if (ltdc->panel) {
>> +            ret = drm_panel_attach(ltdc->panel, connector);
>> +            if (!ret || ret == -EBUSY) {
>> +                    DRM_DEBUG_DRIVER("connector status connected");
>> +                    return connector_status_connected;
>> +            }
>> +    }
>> +    DRM_DEBUG_DRIVER("connector status disconnected");
>> +
>> +    return connector_status_disconnected;
>> +}
>
> In vc4 and other drivers I've looked at, we drm_panel_attach at load
> time, so detect is just return ltdc->panel ? connected : disconnected.
>
Ok, Done
I call drm_panel_detach at unload time.

>> +static void ltdc_rgb_connector_destroy(struct drm_connector *connector)
>> +{
>> +    struct ltdc *ltdc = connector_to_ltdc(connector);
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    if (ltdc->panel)
>> +            drm_panel_detach(ltdc->panel);
>> +    drm_connector_cleanup(connector);
>> +}
>> +
>> +static const struct drm_connector_funcs ltdc_rgb_connector_funcs = {
>> +    .dpms = drm_atomic_helper_connector_dpms,
>> +    .fill_modes = drm_helper_probe_single_connector_modes,
>> +    .detect = ltdc_rgb_connector_detect,
>> +    .destroy = ltdc_rgb_connector_destroy,
>> +    .reset = drm_atomic_helper_connector_reset,
>> +    .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
>> +    .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
>> +};
>> +
>> +struct drm_connector *ltdc_rgb_connector_create(struct drm_device *ddev)
>> +{
>> +    struct drm_connector *connector;
>> +    int err;
>> +
>> +    connector = devm_kzalloc(ddev->dev, sizeof(*connector), GFP_KERNEL);
>> +    if (!connector) {
>> +            DRM_ERROR("Failed to allocate connector\n");
>> +            return NULL;
>> +    }
>> +
>> +    connector->polled = DRM_CONNECTOR_POLL_HPD;
>> +
>> +    err = drm_connector_init(ddev, connector, &ltdc_rgb_connector_funcs,
>> +                             DRM_MODE_CONNECTOR_LVDS);
>> +    if (err) {
>> +            DRM_ERROR("Failed to initialize connector\n");
>> +            return NULL;
>> +    }
>> +
>> +    drm_connector_helper_add(connector, &ltdc_rgb_connector_helper_funcs);
>> +
>> +    DRM_DEBUG_DRIVER("RGB connector:%d created\n", connector->base.id);
>> +
>> +    return connector;
>> +}
>> +
>> +static int ltdc_get_caps(struct ltdc *ltdc)
>> +{
>> +    u32 bus_width_log2, lcr, gc2r;
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return -EINVAL;
>> +    }
>> +
>> +    /* at least 1 layer must be managed */
>> +    lcr = reg_read(ltdc->regs, LTDC_LCR);
>> +
>> +    ltdc->caps.nb_layers = max_t(int, lcr, 1);
>> +
>> +    /* set data bus width */
>> +    gc2r = reg_read(ltdc->regs, LTDC_GC2R);
>> +    bus_width_log2 = (gc2r & GC2R_BW) >> 4;
>> +    ltdc->caps.bus_width = 8 << bus_width_log2;
>> +    ltdc->caps.hw_version = reg_read(ltdc->regs, LTDC_IDR);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +
>> +    switch (ltdc->caps.hw_version) {
>> +    case HWVER_10200:
>> +    case HWVER_10300:
>> +            ltdc->caps.reg_ofs = REG_OFS_NONE;
>> +            ltdc->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
>> +            break;
>> +    case HWVER_20101:
>> +            ltdc->caps.reg_ofs = REG_OFS_4;
>> +            ltdc->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
>> +            break;
>> +    default:
>> +            return -ENODEV;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
>> +{
>> +    struct device *dev = ddev->dev;
>> +    struct device_node *np = dev->of_node;
>> +    struct device_node *entity, *port = NULL;
>> +    struct drm_panel *panel = NULL;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    /*
>> +     * Parse ltdc node to get remote port and find RGB panel / HDMI slave
>> +     * If a dsi or a bridge (hdmi, lvds...) is connected to ltdc,
>> +     * a remote port & RGB panel will not be found.
>> +     */
>> +    for_each_endpoint_of_node(np, entity) {
>> +            if (!of_device_is_available(entity))
>> +                    continue;
>> +
>> +            port = of_graph_get_remote_port_parent(entity);
>> +            if (port) {
>> +                    panel = of_drm_find_panel(port);
>> +                    of_node_put(port);
>> +                    if (panel) {
>> +                            DRM_DEBUG_DRIVER("remote panel %s\n",
>> +                                             port->full_name);
>> +                    } else {
>> +                            DRM_DEBUG_DRIVER("panel missing\n");
>> +                            of_node_put(entity);
>> +                    }
>> +            }
>> +    }
>> +
>> +    return panel;
>> +}
>> +
>> +int ltdc_load(struct drm_device *ddev)
>> +{
>> +    struct platform_device *pdev = to_platform_device(ddev->dev);
>> +    struct stm_private *priv = ddev->dev_private;
>> +    struct device *dev = ddev->dev;
>> +    struct device_node *np = dev->of_node;
>> +    struct drm_encoder *encoder;
>> +    struct drm_connector *connector = NULL;
>> +    struct drm_crtc *crtc;
>> +    struct reset_control *rstc;
>> +    struct resource res;
>> +    struct ltdc *ltdc;
>> +    int irq, ret, i;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    ltdc = devm_kzalloc(dev, sizeof(*ltdc), GFP_KERNEL);
>> +    if (!ltdc) {
>> +            DRM_ERROR("Cannot allocate memory for ltdc\n");
>> +            return -ENOMEM;
>> +    }
>> +
>> +    ltdc->panel = ltdc_get_panel(ddev);
>> +    if (!ltdc->panel)
>> +            return -EPROBE_DEFER;
>> +
>> +    ltdc->ddev = ddev;
>> +    priv->ltdc = ltdc;
>> +
>> +    rstc = of_reset_control_get(np, NULL);
>> +
>> +    mutex_init(&ltdc->err_lock);
>> +
>> +    ltdc->pixel_clk = devm_clk_get(dev, "lcd");
>> +    if (IS_ERR(ltdc->pixel_clk)) {
>> +            DRM_ERROR("Unable to get lcd clock\n");
>> +            return -ENODEV;
>> +    }
>> +
>> +    if (clk_prepare(ltdc->pixel_clk)) {
>> +            DRM_ERROR("Unable to prepare pixel clock\n");
>> +            return -ENODEV;
>> +    }
>> +
>> +    if (of_address_to_resource(np, 0, &res)) {
>> +            DRM_ERROR("Unable to get resource\n");
>> +            return -ENODEV;
>> +    }
>> +
>> +    ltdc->regs = devm_ioremap_resource(dev, &res);
>> +    if (IS_ERR(ltdc->regs)) {
>> +            DRM_ERROR("Unable to get ltdc registers\n");
>> +            return PTR_ERR(ltdc->regs);
>> +    }
>> +
>> +    for (i = 0; i < MAX_IRQ; i++) {
>> +            irq = platform_get_irq(pdev, i);
>> +            if (irq < 0)
>> +                    continue;
>> +
>> +            ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
>> +                                            ltdc_irq_thread, IRQF_ONESHOT,
>> +                                            dev_name(dev), ltdc);
>> +            if (ret) {
>> +                    DRM_ERROR("Failed to register LTDC interrupt\n");
>> +                    return ret;
>> +            }
>> +    }
>
> Up to four IRQs that call the same irq handler with the same args?  That
> seems suspicious.
>
Yes, Ltdc contains four IRQs & chipset link them on one or two lines.
>> +
>> +    if (!IS_ERR(rstc))
>> +            reset_control_deassert(rstc);
>> +
>> +    if (clk_enable(ltdc->pixel_clk)) {
>> +            DRM_ERROR("failed to enable pixel clock\n");
>> +            return -EINVAL;
>> +    }
>> +
>> +    /* Disable interrupts */
>> +    reg_clear(ltdc->regs, LTDC_IER,
>> +              IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
>> +
>> +    clk_disable(ltdc->pixel_clk);
>> +
>> +    ret = ltdc_get_caps(ltdc);
>> +    if (ret) {
>> +            DRM_ERROR("hardware identifier (0x%08x) not supported!\n",
>> +                      ltdc->caps.hw_version);
>> +            return ret;
>> +    }
>> +
>> +    DRM_INFO("ltdc hw version 0x%08x - ready\n", ltdc->caps.hw_version);
>> +
>> +    if (ltdc_create_encoders(ltdc)) {
>> +            DRM_ERROR("Failed to create encoders\n");
>> +            return -EINVAL;
>> +    }
>> +
>> +    if (ltdc->panel) {
>> +            encoder = ltdc_rgb_encoder_find(ddev);
>> +            if (!encoder) {
>> +                    DRM_ERROR("Failed to find RGB encoder\n");
>> +                    ret = -EINVAL;
>> +                    goto err_encoder;
>> +            }
>> +
>> +            connector = ltdc_rgb_connector_create(ddev);
>> +            if (!connector) {
>> +                    DRM_ERROR("Failed to create RGB connector\n");
>> +                    ret = -EINVAL;
>> +                    goto err_encoder;
>> +            }
>> +
>> +            ret = drm_mode_connector_attach_encoder(connector, encoder);
>> +            if (ret) {
>> +                    DRM_ERROR("Failed to attach connector to encoder\n");
>> +                    goto err_connector;
>> +            }
>> +    }
>> +
>> +    crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
>> +    if (!crtc) {
>> +            DRM_ERROR("Failed to allocate crtc\n");
>> +            ret = -ENOMEM;
>> +            goto err_connector;
>> +    }
>> +
>> +    ret = ltdc_crtc_init(ddev, crtc);
>> +    if (ret) {
>> +            DRM_ERROR("Failed to init crtc\n");
>> +            goto err_connector;
>> +    }
>> +
>> +    ret = drm_vblank_init(ddev, NB_CRTC);
>> +    if (ret) {
>> +            DRM_ERROR("Failed calling drm_vblank_init()\n");
>> +            goto err_vblank;
>> +    }
>> +
>> +    /* Allow usage of vblank without having to call drm_irq_install */
>> +    ddev->irq_enabled = 1;
>> +
>> +    return 0;
>> +
>> +err_vblank:
>> +    ltdc_plane_destroy_all(ltdc);
>> +err_connector:
>> +    ltdc_rgb_connector_destroy(connector);
>> +err_encoder:
>> +    ltdc_destroy_encoders(ltdc);
>
> In pl111, I just call drm_mode_config_cleanup here and in the unload,
> which will call the objects' destroy functions for you.
>
Ok, Done
>> +
>> +    return ret;
>> +}
>> +
>> +void ltdc_unload(struct drm_device *ddev)
>> +{
>> +    struct stm_private *priv = ddev->dev_private;
>> +    struct ltdc *ltdc = priv->ltdc;
>> +
>> +    DRM_DEBUG_DRIVER("\n");
>> +
>> +    drm_vblank_cleanup(ddev);
>> +    ltdc_plane_destroy_all(ltdc);
>> +    ltdc_destroy_encoders(ltdc);
>> +    clk_unprepare(ltdc->pixel_clk);
>> +}
>> +
>> +MODULE_AUTHOR("Philippe Cornu <philippe.co...@st.com>");
>> +MODULE_AUTHOR("Yannick Fertre <yannick.fer...@st.com>");
>> +MODULE_AUTHOR("Fabien Dessenne <fabien.desse...@st.com>");
>> +MODULE_AUTHOR("Mickael Reulier <mickael.reul...@st.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
>> new file mode 100644
>> index 0000000..d1f9e35
>> --- /dev/null
>> +++ b/drivers/gpu/drm/stm/ltdc.h
>> @@ -0,0 +1,22 @@
>> +/*
>> + * Copyright (C) STMicroelectronics SA 2017
>> + *
>> + * Authors: Philippe Cornu <philippe.co...@st.com>
>> + *          Yannick Fertre <yannick.fer...@st.com>
>> + *          Fabien Dessenne <fabien.desse...@st.com>
>> + *          Mickael Reulier <mickael.reul...@st.com>
>> + *
>> + * License terms:  GNU General Public License (GPL), version 2
>> + */
>> +
>> +#ifndef _LTDC_H_
>> +#define _LTDC_H_
>> +
>> +#include <drm/drmP.h>
>> +
>> +int ltdc_crtc_enable_vblank(struct drm_device *dev, unsigned int pipe);
>> +void ltdc_crtc_disable_vblank(struct drm_device *dev, unsigned int pipe);
>> +int ltdc_load(struct drm_device *ddev);
>> +void ltdc_unload(struct drm_device *ddev);
>> +
>> +#endif
>> --
>> 1.9.1
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
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