Re: [PATCH] drm/mediatek: fixup error memory reallocation

From: CK Hu
Date: Tue Jun 13 2017 - 21:19:59 EST


On Mon, 2017-06-12 at 15:15 +0800, YT Shen wrote:
> Previous patch (c5f228ef6c drm/mediatek: add *driver_data for different
> hardware settings) calls devm_kfree() and then devm_kzalloc() to
> reallocate color module data structure. But this reallocation cannnot
> guarantee the new address is unchanged, but the caller will use the
> old address, which is wrong.
>
> Fix it by separate color module from general components, this patch
> separate color module to independent files, like mtk_disp_ovl.c and
> mtk_disp_rdma.c do
>

Hi, YT:

I would like the title to be something like 'separate color module to
fixup error memory reallocation' because this is a large modification
and its major is separating color module.

Regards,
CK

> Signed-off-by: YT Shen <yt.shen@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/Makefile | 3 +-
> drivers/gpu/drm/mediatek/mtk_disp_color.c | 176 ++++++++++++++++++++++++++++
> drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 80 +------------
> drivers/gpu/drm/mediatek/mtk_drm_drv.c | 6 +-
> drivers/gpu/drm/mediatek/mtk_drm_drv.h | 1 +
> 5 files changed, 185 insertions(+), 81 deletions(-)
> create mode 100644 drivers/gpu/drm/mediatek/mtk_disp_color.c
>
> diff --git a/drivers/gpu/drm/mediatek/Makefile b/drivers/gpu/drm/mediatek/Makefile
> index bf2e5be..e37b55a 100644
> --- a/drivers/gpu/drm/mediatek/Makefile
> +++ b/drivers/gpu/drm/mediatek/Makefile
> @@ -1,4 +1,5 @@
> -mediatek-drm-y := mtk_disp_ovl.o \
> +mediatek-drm-y := mtk_disp_color.o \
> + mtk_disp_ovl.o \
> mtk_disp_rdma.o \
> mtk_drm_crtc.o \
> mtk_drm_ddp.o \
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_color.c b/drivers/gpu/drm/mediatek/mtk_disp_color.c
> new file mode 100644
> index 0000000..ef79a6d
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_color.c
> @@ -0,0 +1,176 @@
> +/*
> + * Copyright (c) 2017 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <drm/drmP.h>
> +#include <linux/clk.h>
> +#include <linux/component.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>
> +#include <linux/platform_device.h>
> +
> +#include "mtk_drm_crtc.h"
> +#include "mtk_drm_ddp_comp.h"
> +
> +#define DISP_COLOR_CFG_MAIN 0x0400
> +#define DISP_COLOR_START_MT2701 0x0f00
> +#define DISP_COLOR_START_MT8173 0x0c00
> +#define DISP_COLOR_START(comp) ((comp)->data->color_offset)
> +#define DISP_COLOR_WIDTH(comp) (DISP_COLOR_START(comp) + 0x50)
> +#define DISP_COLOR_HEIGHT(comp) (DISP_COLOR_START(comp) + 0x54)
> +
> +#define COLOR_BYPASS_ALL BIT(7)
> +#define COLOR_SEQ_SEL BIT(13)
> +
> +struct mtk_disp_color_data {
> + unsigned int color_offset;
> +};
> +
> +/**
> + * struct mtk_disp_color - DISP_COLOR driver structure
> + * @ddp_comp - structure containing type enum and hardware resources
> + * @crtc - associated crtc to report irq events to
> + */
> +struct mtk_disp_color {
> + struct mtk_ddp_comp ddp_comp;
> + struct drm_crtc *crtc;
> + const struct mtk_disp_color_data *data;
> +};
> +
> +static inline struct mtk_disp_color *comp_to_color(struct mtk_ddp_comp *comp)
> +{
> + return container_of(comp, struct mtk_disp_color, ddp_comp);
> +}
> +
> +static void mtk_color_config(struct mtk_ddp_comp *comp, unsigned int w,
> + unsigned int h, unsigned int vrefresh,
> + unsigned int bpc)
> +{
> + struct mtk_disp_color *color = comp_to_color(comp);
> +
> + writel(w, comp->regs + DISP_COLOR_WIDTH(color));
> + writel(h, comp->regs + DISP_COLOR_HEIGHT(color));
> +}
> +
> +static void mtk_color_start(struct mtk_ddp_comp *comp)
> +{
> + struct mtk_disp_color *color = comp_to_color(comp);
> +
> + writel(COLOR_BYPASS_ALL | COLOR_SEQ_SEL,
> + comp->regs + DISP_COLOR_CFG_MAIN);
> + writel(0x1, comp->regs + DISP_COLOR_START(color));
> +}
> +
> +static const struct mtk_ddp_comp_funcs mtk_disp_color_funcs = {
> + .config = mtk_color_config,
> + .start = mtk_color_start,
> +};
> +
> +static int mtk_disp_color_bind(struct device *dev, struct device *master,
> + void *data)
> +{
> + struct mtk_disp_color *priv = dev_get_drvdata(dev);
> + struct drm_device *drm_dev = data;
> + int ret;
> +
> + ret = mtk_ddp_comp_register(drm_dev, &priv->ddp_comp);
> + if (ret < 0) {
> + dev_err(dev, "Failed to register component %s: %d\n",
> + dev->of_node->full_name, ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void mtk_disp_color_unbind(struct device *dev, struct device *master,
> + void *data)
> +{
> + struct mtk_disp_color *priv = dev_get_drvdata(dev);
> + struct drm_device *drm_dev = data;
> +
> + mtk_ddp_comp_unregister(drm_dev, &priv->ddp_comp);
> +}
> +
> +static const struct component_ops mtk_disp_color_component_ops = {
> + .bind = mtk_disp_color_bind,
> + .unbind = mtk_disp_color_unbind,
> +};
> +
> +static int mtk_disp_color_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct mtk_disp_color *priv;
> + int comp_id;
> + int ret;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DISP_COLOR);
> + if (comp_id < 0) {
> + dev_err(dev, "Failed to identify by alias: %d\n", comp_id);
> + return comp_id;
> + }
> +
> + ret = mtk_ddp_comp_init(dev, dev->of_node, &priv->ddp_comp, comp_id,
> + &mtk_disp_color_funcs);
> + if (ret) {
> + dev_err(dev, "Failed to initialize component: %d\n", ret);
> + return ret;
> + }
> +
> + priv->data = of_device_get_match_data(dev);
> +
> + platform_set_drvdata(pdev, priv);
> +
> + ret = component_add(dev, &mtk_disp_color_component_ops);
> + if (ret)
> + dev_err(dev, "Failed to add component: %d\n", ret);
> +
> + return ret;
> +}
> +
> +static int mtk_disp_color_remove(struct platform_device *pdev)
> +{
> + component_del(&pdev->dev, &mtk_disp_color_component_ops);
> +
> + return 0;
> +}
> +
> +static const struct mtk_disp_color_data mt2701_color_driver_data = {
> + .color_offset = DISP_COLOR_START_MT2701,
> +};
> +
> +static const struct mtk_disp_color_data mt8173_color_driver_data = {
> + .color_offset = DISP_COLOR_START_MT8173,
> +};
> +
> +static const struct of_device_id mtk_disp_color_driver_dt_match[] = {
> + { .compatible = "mediatek,mt2701-disp-color",
> + .data = &mt2701_color_driver_data},
> + { .compatible = "mediatek,mt8173-disp-color",
> + .data = &mt8173_color_driver_data},
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, mtk_disp_color_driver_dt_match);
> +
> +struct platform_driver mtk_disp_color_driver = {
> + .probe = mtk_disp_color_probe,
> + .remove = mtk_disp_color_remove,
> + .driver = {
> + .name = "mediatek-disp-color",
> + .owner = THIS_MODULE,
> + .of_match_table = mtk_disp_color_driver_dt_match,
> + },
> +};
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> index 8b52416..07d7ea2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> @@ -38,13 +38,6 @@
>
> #define DISP_REG_UFO_START 0x0000
>
> -#define DISP_COLOR_CFG_MAIN 0x0400
> -#define DISP_COLOR_START_MT2701 0x0f00
> -#define DISP_COLOR_START_MT8173 0x0c00
> -#define DISP_COLOR_START(comp) ((comp)->data->color_offset)
> -#define DISP_COLOR_WIDTH(comp) (DISP_COLOR_START(comp) + 0x50)
> -#define DISP_COLOR_HEIGHT(comp) (DISP_COLOR_START(comp) + 0x54)
> -
> #define DISP_AAL_EN 0x0000
> #define DISP_AAL_SIZE 0x0030
>
> @@ -55,9 +48,6 @@
>
> #define LUT_10BIT_MASK 0x03ff
>
> -#define COLOR_BYPASS_ALL BIT(7)
> -#define COLOR_SEQ_SEL BIT(13)
> -
> #define OD_RELAYMODE BIT(0)
>
> #define UFO_BYPASS BIT(2)
> @@ -82,20 +72,6 @@
> #define DITHER_ADD_LSHIFT_G(x) (((x) & 0x7) << 4)
> #define DITHER_ADD_RSHIFT_G(x) (((x) & 0x7) << 0)
>
> -struct mtk_disp_color_data {
> - unsigned int color_offset;
> -};
> -
> -struct mtk_disp_color {
> - struct mtk_ddp_comp ddp_comp;
> - const struct mtk_disp_color_data *data;
> -};
> -
> -static inline struct mtk_disp_color *comp_to_color(struct mtk_ddp_comp *comp)
> -{
> - return container_of(comp, struct mtk_disp_color, ddp_comp);
> -}
> -
> void mtk_dither_set(struct mtk_ddp_comp *comp, unsigned int bpc,
> unsigned int CFG)
> {
> @@ -119,25 +95,6 @@ void mtk_dither_set(struct mtk_ddp_comp *comp, unsigned int bpc,
> }
> }
>
> -static void mtk_color_config(struct mtk_ddp_comp *comp, unsigned int w,
> - unsigned int h, unsigned int vrefresh,
> - unsigned int bpc)
> -{
> - struct mtk_disp_color *color = comp_to_color(comp);
> -
> - writel(w, comp->regs + DISP_COLOR_WIDTH(color));
> - writel(h, comp->regs + DISP_COLOR_HEIGHT(color));
> -}
> -
> -static void mtk_color_start(struct mtk_ddp_comp *comp)
> -{
> - struct mtk_disp_color *color = comp_to_color(comp);
> -
> - writel(COLOR_BYPASS_ALL | COLOR_SEQ_SEL,
> - comp->regs + DISP_COLOR_CFG_MAIN);
> - writel(0x1, comp->regs + DISP_COLOR_START(color));
> -}
> -
> static void mtk_od_config(struct mtk_ddp_comp *comp, unsigned int w,
> unsigned int h, unsigned int vrefresh,
> unsigned int bpc)
> @@ -229,11 +186,6 @@ static void mtk_gamma_set(struct mtk_ddp_comp *comp,
> .stop = mtk_gamma_stop,
> };
>
> -static const struct mtk_ddp_comp_funcs ddp_color = {
> - .config = mtk_color_config,
> - .start = mtk_color_start,
> -};
> -
> static const struct mtk_ddp_comp_funcs ddp_od = {
> .config = mtk_od_config,
> .start = mtk_od_start,
> @@ -268,8 +220,8 @@ struct mtk_ddp_comp_match {
> static const struct mtk_ddp_comp_match mtk_ddp_matches[DDP_COMPONENT_ID_MAX] = {
> [DDP_COMPONENT_AAL] = { MTK_DISP_AAL, 0, &ddp_aal },
> [DDP_COMPONENT_BLS] = { MTK_DISP_BLS, 0, NULL },
> - [DDP_COMPONENT_COLOR0] = { MTK_DISP_COLOR, 0, &ddp_color },
> - [DDP_COMPONENT_COLOR1] = { MTK_DISP_COLOR, 1, &ddp_color },
> + [DDP_COMPONENT_COLOR0] = { MTK_DISP_COLOR, 0, NULL },
> + [DDP_COMPONENT_COLOR1] = { MTK_DISP_COLOR, 1, NULL },
> [DDP_COMPONENT_DPI0] = { MTK_DPI, 0, NULL },
> [DDP_COMPONENT_DSI0] = { MTK_DSI, 0, NULL },
> [DDP_COMPONENT_DSI1] = { MTK_DSI, 1, NULL },
> @@ -286,22 +238,6 @@ struct mtk_ddp_comp_match {
> [DDP_COMPONENT_WDMA1] = { MTK_DISP_WDMA, 1, NULL },
> };
>
> -static const struct mtk_disp_color_data mt2701_color_driver_data = {
> - .color_offset = DISP_COLOR_START_MT2701,
> -};
> -
> -static const struct mtk_disp_color_data mt8173_color_driver_data = {
> - .color_offset = DISP_COLOR_START_MT8173,
> -};
> -
> -static const struct of_device_id mtk_disp_color_driver_dt_match[] = {
> - { .compatible = "mediatek,mt2701-disp-color",
> - .data = &mt2701_color_driver_data},
> - { .compatible = "mediatek,mt8173-disp-color",
> - .data = &mt8173_color_driver_data},
> - {},
> -};
> -
> int mtk_ddp_comp_get_id(struct device_node *node,
> enum mtk_ddp_comp_type comp_type)
> {
> @@ -324,23 +260,11 @@ int mtk_ddp_comp_init(struct device *dev, struct device_node *node,
> enum mtk_ddp_comp_type type;
> struct device_node *larb_node;
> struct platform_device *larb_pdev;
> - const struct of_device_id *match;
> - struct mtk_disp_color *color;
>
> if (comp_id < 0 || comp_id >= DDP_COMPONENT_ID_MAX)
> return -EINVAL;
>
> type = mtk_ddp_matches[comp_id].type;
> - if (type == MTK_DISP_COLOR) {
> - devm_kfree(dev, comp);
> - color = devm_kzalloc(dev, sizeof(*color), GFP_KERNEL);
> - if (!color)
> - return -ENOMEM;
> -
> - match = of_match_node(mtk_disp_color_driver_dt_match, node);
> - color->data = match->data;
> - comp = &color->ddp_comp;
> - }
>
> comp->id = comp_id;
> comp->funcs = funcs ?: mtk_ddp_matches[comp_id].funcs;
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> index f6c8ec4..9287fba 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> @@ -439,11 +439,12 @@ static int mtk_drm_probe(struct platform_device *pdev)
> private->comp_node[comp_id] = of_node_get(node);
>
> /*
> - * Currently only the OVL, RDMA, DSI, and DPI blocks have
> + * Currently only the COLOR, OVL, RDMA, DSI, and DPI blocks have
> * separate component platform drivers and initialize their own
> * DDP component structure. The others are initialized here.
> */
> - if (comp_type == MTK_DISP_OVL ||
> + if (comp_type == MTK_DISP_COLOR ||
> + comp_type == MTK_DISP_OVL ||
> comp_type == MTK_DISP_RDMA ||
> comp_type == MTK_DSI ||
> comp_type == MTK_DPI) {
> @@ -566,6 +567,7 @@ static SIMPLE_DEV_PM_OPS(mtk_drm_pm_ops, mtk_drm_sys_suspend,
>
> static struct platform_driver * const mtk_drm_drivers[] = {
> &mtk_ddp_driver,
> + &mtk_disp_color_driver,
> &mtk_disp_ovl_driver,
> &mtk_disp_rdma_driver,
> &mtk_dpi_driver,
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> index aef8747..c3378c4 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> @@ -59,6 +59,7 @@ struct mtk_drm_private {
> };
>
> extern struct platform_driver mtk_ddp_driver;
> +extern struct platform_driver mtk_disp_color_driver;
> extern struct platform_driver mtk_disp_ovl_driver;
> extern struct platform_driver mtk_disp_rdma_driver;
> extern struct platform_driver mtk_dpi_driver;