Android亮屏速度分析總結

2019-10-21 21:25:50

字體：大中小

來源：轉載

供稿：網友

前面聊的

最近在調試項目的亮屏速度，我們希望在按下power鍵后到亮屏這個時間能達到500MS以內，在Rockchip 3399和3288上面的時間都不能達到要求，因此引發了一系列的調試之路。

計算按下power鍵到亮屏的時間

Android 喚醒時間統計

剛開始的時候，我只在android階段統計時間，也能看到時間的差異，但是不是最準確的，我統計的時間日志如下

01-18 09:13:40.992 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 743ms
01-18 09:13:45.304 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 757ms
01-18 09:13:49.559 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 725ms
01-18 09:18:27.461 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 741ms
01-18 09:18:32.766 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 743ms
01-18 09:18:35.861 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 745ms
01-18 09:18:38.345 683 772 D SurfaceControl: Excessive delay in setPowerMode(): 733ms

Kernel從Power到亮屏的時間統計

后來同事中的精英古總在他的代碼上加入了從按下Power鍵到亮屏的時間，直接通過printk打印，代碼如下

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.cold mode 100644new mode 100755index 17c3b94..2b39662--- a/drivers/gpu/drm/panel/panel-simple.c+++ b/drivers/gpu/drm/panel/panel-simple.c@@ -504,6 +504,7 @@ static int panel_simple_enable(struct drm_panel *panel)    }    p->enabled = true;+    printk("%s exit/n", __func__);    return 0; }diff --git a/drivers/input/keyboard/rk_keys.c b/drivers/input/keyboard/rk_keys.cold mode 100644new mode 100755index fed5ced..537b599--- a/drivers/input/keyboard/rk_keys.c+++ b/drivers/input/keyboard/rk_keys.c@@ -134,6 +134,10 @@ static void keys_timer(unsigned long _data)        key_dbg(pdata, "%skey[%s]: report event[%d] state[%d]/n",            button->type == TYPE_ADC ? "adc" : "gpio",            button->desc, button->code, button->state);+        if(strcmp(button->desc, "power") == 0)+        printk("%skey[%s]: report event[%d] state[%d]/n",+            button->type == TYPE_ADC ? "adc" : "gpio",+            button->desc, button->code, button->state);        input_event(input, EV_KEY, button->code, button->state);        input_sync(input);    }

統計每個驅動的resume函數調用時間

上面的時間對我們調試非常有用，然后就需要細分到每個驅動的resume函數執行的時間，用的方法是我之前寫過的，大概統計了下TP，LCD，sensor的resume時間，發現TP和LCD占用的時間非常多，然后跟同事一起看了下，同事把TP resume里面的代碼用工作隊列實現后速度明顯有了提升。

然后有很長一段時間不知道干嘛，向打印其他每個驅動的resume時間，一直沒找到方法，后面看到一個代碼，非常有用。

kernel/drivers/base/power/main.c

static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info)                            {          ktime_t calltime;  u64 usecs64;  int usecs;  calltime = ktime_get();  usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));  do_div(usecs64, NSEC_PER_USEC);  usecs = usecs64;  if (usecs == 0)    usecs = 1;   pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs/n",    info ?: "", info ? " " : "", pm_verb(state.event),    usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);}

這個函數用來打印resume的函數消耗的時間，但是如何去觸發打印這個函數呢?

一定保證設備進入深度睡眠，串口也進入深度睡眠，沒有任何打印后。
執行以下命令

echo N > /sys/module/printk/parameters/console_suspend//使控制臺在suspend最后才關閉，這樣可以打印出休眠過程完整信息echo 1 > /sys/power/pm_print_times//使能調試變量

打印的LOG類似下面的

[ 37.031413] bcmsdh_sdmmc_resume Exit
[ 37.082174] PM: resume of devices complete after 78.589 msecs
[ 37.085277] [BT_RFKILL]: ** disable irq
[ 37.087645] Restarting tasks ...

修改Lcd配置減小resume時間

古總在調試過程中展現了非常厲害的功底，第一步就是修改了LCD的參數，讓亮屏時間加快。修改如下

--- a/arch/arm/boot/dts/rk3288-pad.dts+++ b/arch/arm/boot/dts/rk3288-pad.dts@@ -169,10 +169,10 @@        dsi,lanes = <4>;        prepare-delay-ms = <20>;-        init-delay-ms = <20>;-        enable-delay-ms = <100>;-        disable-delay-ms = <20>;-        unprepare-delay-ms = <20>;+        //init-delay-ms = <20>;+        enable-delay-ms = <1>;+        disable-delay-ms = <1>;+        unprepare-delay-ms = <1>;        panel-init-sequence = [            15 32 02 8F A5            15 01 02 83 00

修改DRM 超時時間減小喚醒時間

這是最關鍵的，DRM框架非常復雜，RK也是從開源的DRM移植過來使用，在DRM部分有個時間導致問題，最終跟RK拿到最新的patch讓喚醒時間直接加速500MS.

我們在日志下發現問題，并給詢問了RK，最終發現這部分代碼沒有更新到最新的部分。

hi rk:
為什么亮屏的時候有時候會打印這句VOP等待超時？請問下這是什么意思。
[ 1211.293492] rockchip-vop ff930000.vop: wait win close timeout
[ 1211.293514] rockchip-vop ff930000.vop: [drm:vop_crtc_enable] Update mode to 1200*1920, close all win
有時候卻不會打印。

[ 1216.423283] rockchip-vop ff930000.vop: [drm:vop_crtc_enable] Update mode to 12001920, close all win [ 1223.899741] rockchip-vop ff930000.vop: [drm:vop_crtc_enable] Update mode to 12001920, close all win
[ 1234.386252] rockchip-vop ff930000.vop: [drm:vop_crtc_enable] Update mode to 1200*1920, close all win

代碼如下

--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c@@ -139,6 +139,9 @@ #define to_vop_win(x) container_of(x, struct vop_win, base) #define to_vop_plane_state(x) container_of(x, struct vop_plane_state, base)+/*add by VENDOR_PATCH for seep up the drm vop driver at 2018/1/18 for RK Defect #191554, VENDOR_PATCH PAD100-193*/+#define VENDOR_PATCH+ struct vop_zpos {    int win_id;    int zpos;@@ -868,9 +871,15 @@ static void vop_disable_all_planes(struct vop *vop)    vop_disable_allwin(vop);    vop_cfg_done(vop);+#ifdef VENDOR_PATCH    ret = readx_poll_timeout_atomic(vop_is_allwin_disabled,                    vop, active, active,+                    0, 100 * 1000);+#else+    ret = readx_poll_timeout_atomic(vop_is_allwin_disabled,+                vop, active, active,                    0, 500 * 1000);+#endif    if (ret)        dev_err(vop->dev, "wait win close timeout/n"); }@@ -2215,20 +2224,36 @@ static size_t vop_crtc_bandwidth(struct drm_crtc *crtc,    u16 htotal = adjusted_mode->crtc_htotal;    u16 vdisplay = adjusted_mode->crtc_vdisplay;    int clock = adjusted_mode->crtc_clock;+#ifndef VENDOR_PATCH    struct vop *vop = to_vop(crtc);    const struct vop_data *vop_data = vop->data;+#endif    struct vop_plane_state *vop_plane_state;    struct drm_plane_state *pstate;    struct vop_bandwidth *pbandwidth;    struct drm_plane *plane;    u64 bandwidth;    int i, cnt = 0;+#ifdef VENDOR_PATCH+    int plane_num = 0;+#endif    if (!htotal || !vdisplay)        return 0;+#ifndef VENDOR_PATCH    pbandwidth = kmalloc_array(vop_data->win_size, sizeof(*pbandwidth),                  GFP_KERNEL);+#else+    for_each_plane_in_state(state, plane, pstate, i) {+        if (pstate->crtc != crtc || !pstate->fb)+            continue;+        plane_num++;+    }+    pbandwidth = kmalloc_array(plane_num, sizeof(*pbandwidth),+                 GFP_KERNEL);+#endif+    if (!pbandwidth)        return -ENOMEM;@@ -2421,7 +2446,10 @@ static void vop_crtc_enable(struct drm_crtc *crtc)    rockchip_set_system_status(sys_status);    mutex_lock(&vop->vop_lock);    vop_initial(crtc);-+#ifdef VENDOR_PATCH+    vop_disable_allwin(vop);+    VOP_CTRL_SET(vop, standby, 0);+#endif    VOP_CTRL_SET(vop, dclk_pol, 1);    val = (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC) ?          0 : BIT(HSYNC_POSITIVE);@@ -2549,8 +2577,9 @@ static void vop_crtc_enable(struct drm_crtc *crtc)    /*     * enable vop, all the register would take effect when vop exit standby     */+#ifndef VENDOR_PATCH    VOP_CTRL_SET(vop, standby, 0);-+#endif    enable_irq(vop->irq);    drm_crtc_vblank_on(crtc);    mutex_unlock(&vop->vop_lock);

休眠喚醒流程圖

從網上拷貝了個休眠喚醒的流程圖，如果以后有問題需要分析的話，可以跟進這個流程去排查。

Android,亮屏