Re: [PATCH v12 11/12] drm/mediatek: update DSI sub driver flow for sending commands to panel

From: CK Hu <ck.hu@mediatek.com>
To: YT Shen <yt.shen@mediatek.com>
Cc: <dri-devel@lists.freedesktop.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	David Airlie <airlied@linux.ie>, Rob Herring <robh+dt@kernel.org>,
	"Mark Rutland" <mark.rutland@arm.com>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	<devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-mediatek@lists.infradead.org>,
	<srv_heupstream@mediatek.com>, <yingjoe.chen@mediatek.com>,
	<emil.l.velikov@gmail.com>, <thierry.reding@gmail.com>,
	Daniel Kurtz <djkurtz@chromium.org>,
	shaoming chen <shaoming.chen@mediatek.com>
Subject: Re: [PATCH v12 11/12] drm/mediatek: update DSI sub driver flow for sending commands to panel
Date: Tue, 24 Jan 2017 13:33:05 +0800	[thread overview]
Message-ID: <1485235985.30572.1.camel@mtksdaap41> (raw)
In-Reply-To: <1485169525-22163-12-git-send-email-yt.shen@mediatek.com>

Hi, YT:

On Mon, 2017-01-23 at 19:05 +0800, YT Shen wrote:
> This patch update enable/disable flow of DSI module.
> Original flow works on there is a bridge chip: DSI -> bridge -> panel.
> In this case: DSI -> panel, the DSI sub driver flow should be updated.
> We need to initialize DSI first so that we can send commands to panel.
> 
> Signed-off-by: shaoming chen <shaoming.chen@mediatek.com>
> Signed-off-by: YT Shen <yt.shen@mediatek.com>

Acked-by: CK Hu <ck.hu@mediatek.com>

> ---
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 266 ++++++++++++++++++++++---------------
>  1 file changed, 161 insertions(+), 105 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 85f22d2..aa3541e 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -126,6 +126,10 @@
>  #define CLK_HS_POST			(0xff << 8)
>  #define CLK_HS_EXIT			(0xff << 16)
>  
> +#define DSI_VM_CMD_CON		0x130
> +#define VM_CMD_EN			BIT(0)
> +#define TS_VFP_EN			BIT(5)
> +
>  #define DSI_CMDQ0		0x180
>  #define CONFIG				(0xff << 0)
>  #define SHORT_PACKET			0
> @@ -239,85 +243,6 @@ static void mtk_dsi_reset_engine(struct mtk_dsi *dsi)
>  	mtk_dsi_mask(dsi, DSI_CON_CTRL, DSI_RESET, 0);
>  }
>  
> -static int mtk_dsi_poweron(struct mtk_dsi *dsi)
> -{
> -	struct device *dev = dsi->dev;
> -	int ret;
> -	u64 pixel_clock, total_bits;
> -	u32 htotal, htotal_bits, bit_per_pixel, overhead_cycles, overhead_bits;
> -
> -	if (++dsi->refcount != 1)
> -		return 0;
> -
> -	switch (dsi->format) {
> -	case MIPI_DSI_FMT_RGB565:
> -		bit_per_pixel = 16;
> -		break;
> -	case MIPI_DSI_FMT_RGB666_PACKED:
> -		bit_per_pixel = 18;
> -		break;
> -	case MIPI_DSI_FMT_RGB666:
> -	case MIPI_DSI_FMT_RGB888:
> -	default:
> -		bit_per_pixel = 24;
> -		break;
> -	}
> -
> -	/**
> -	 * vm.pixelclock is in kHz, pixel_clock unit is Hz, so multiply by 1000
> -	 * htotal_time = htotal * byte_per_pixel / num_lanes
> -	 * overhead_time = lpx + hs_prepare + hs_zero + hs_trail + hs_exit
> -	 * mipi_ratio = (htotal_time + overhead_time) / htotal_time
> -	 * data_rate = pixel_clock * bit_per_pixel * mipi_ratio / num_lanes;
> -	 */
> -	pixel_clock = dsi->vm.pixelclock * 1000;
> -	htotal = dsi->vm.hactive + dsi->vm.hback_porch + dsi->vm.hfront_porch +
> -			dsi->vm.hsync_len;
> -	htotal_bits = htotal * bit_per_pixel;
> -
> -	overhead_cycles = T_LPX + T_HS_PREP + T_HS_ZERO + T_HS_TRAIL +
> -			T_HS_EXIT;
> -	overhead_bits = overhead_cycles * dsi->lanes * 8;
> -	total_bits = htotal_bits + overhead_bits;
> -
> -	dsi->data_rate = DIV_ROUND_UP_ULL(pixel_clock * total_bits,
> -					  htotal * dsi->lanes);
> -
> -	ret = clk_set_rate(dsi->hs_clk, dsi->data_rate);
> -	if (ret < 0) {
> -		dev_err(dev, "Failed to set data rate: %d\n", ret);
> -		goto err_refcount;
> -	}
> -
> -	phy_power_on(dsi->phy);
> -
> -	ret = clk_prepare_enable(dsi->engine_clk);
> -	if (ret < 0) {
> -		dev_err(dev, "Failed to enable engine clock: %d\n", ret);
> -		goto err_phy_power_off;
> -	}
> -
> -	ret = clk_prepare_enable(dsi->digital_clk);
> -	if (ret < 0) {
> -		dev_err(dev, "Failed to enable digital clock: %d\n", ret);
> -		goto err_disable_engine_clk;
> -	}
> -
> -	mtk_dsi_enable(dsi);
> -	mtk_dsi_reset_engine(dsi);
> -	mtk_dsi_phy_timconfig(dsi);
> -
> -	return 0;
> -
> -err_disable_engine_clk:
> -	clk_disable_unprepare(dsi->engine_clk);
> -err_phy_power_off:
> -	phy_power_off(dsi->phy);
> -err_refcount:
> -	dsi->refcount--;
> -	return ret;
> -}
> -
>  static void mtk_dsi_clk_ulp_mode_enter(struct mtk_dsi *dsi)
>  {
>  	mtk_dsi_mask(dsi, DSI_PHY_LCCON, LC_HS_TX_EN, 0);
> @@ -365,16 +290,23 @@ static void mtk_dsi_set_mode(struct mtk_dsi *dsi)
>  	u32 vid_mode = CMD_MODE;
>  
>  	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
> -		vid_mode = SYNC_PULSE_MODE;
> -
> -		if ((dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) &&
> -		    !(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE))
> +		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
>  			vid_mode = BURST_MODE;
> +		else if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
> +			vid_mode = SYNC_PULSE_MODE;
> +		else
> +			vid_mode = SYNC_EVENT_MODE;
>  	}
>  
>  	writel(vid_mode, dsi->regs + DSI_MODE_CTRL);
>  }
>  
> +static void mtk_dsi_set_vm_cmd(struct mtk_dsi *dsi)
> +{
> +	mtk_dsi_mask(dsi, DSI_VM_CMD_CON, VM_CMD_EN, VM_CMD_EN);
> +	mtk_dsi_mask(dsi, DSI_VM_CMD_CON, TS_VFP_EN, TS_VFP_EN);
> +}
> +
>  static void mtk_dsi_ps_control_vact(struct mtk_dsi *dsi)
>  {
>  	struct videomode *vm = &dsi->vm;
> @@ -512,6 +444,16 @@ static void mtk_dsi_start(struct mtk_dsi *dsi)
>  	writel(1, dsi->regs + DSI_START);
>  }
>  
> +static void mtk_dsi_stop(struct mtk_dsi *dsi)
> +{
> +	writel(0, dsi->regs + DSI_START);
> +}
> +
> +static void mtk_dsi_set_cmd_mode(struct mtk_dsi *dsi)
> +{
> +	writel(CMD_MODE, dsi->regs + DSI_MODE_CTRL);
> +}
> +
>  static void mtk_dsi_set_interrupt_enable(struct mtk_dsi *dsi)
>  {
>  	u32 inten = LPRX_RD_RDY_INT_FLAG | CMD_DONE_INT_FLAG | VM_DONE_INT_FLAG;
> @@ -570,6 +512,121 @@ static irqreturn_t mtk_dsi_irq(int irq, void *dev_id)
>  	return IRQ_HANDLED;
>  }
>  
> +static s32 mtk_dsi_switch_to_cmd_mode(struct mtk_dsi *dsi, u8 irq_flag, u32 t)
> +{
> +	mtk_dsi_irq_data_clear(dsi, irq_flag);
> +	mtk_dsi_set_cmd_mode(dsi);
> +
> +	if (!mtk_dsi_wait_for_irq_done(dsi, irq_flag, t)) {
> +		DRM_ERROR("failed to switch cmd mode\n");
> +		return -ETIME;
> +	} else {
> +		return 0;
> +	}
> +}
> +
> +static int mtk_dsi_poweron(struct mtk_dsi *dsi)
> +{
> +	struct device *dev = dsi->dev;
> +	int ret;
> +	u64 pixel_clock, total_bits;
> +	u32 htotal, htotal_bits, bit_per_pixel, overhead_cycles, overhead_bits;
> +
> +	if (++dsi->refcount != 1)
> +		return 0;
> +
> +	switch (dsi->format) {
> +	case MIPI_DSI_FMT_RGB565:
> +		bit_per_pixel = 16;
> +		break;
> +	case MIPI_DSI_FMT_RGB666_PACKED:
> +		bit_per_pixel = 18;
> +		break;
> +	case MIPI_DSI_FMT_RGB666:
> +	case MIPI_DSI_FMT_RGB888:
> +	default:
> +		bit_per_pixel = 24;
> +		break;
> +	}
> +
> +	/**
> +	 * vm.pixelclock is in kHz, pixel_clock unit is Hz, so multiply by 1000
> +	 * htotal_time = htotal * byte_per_pixel / num_lanes
> +	 * overhead_time = lpx + hs_prepare + hs_zero + hs_trail + hs_exit
> +	 * mipi_ratio = (htotal_time + overhead_time) / htotal_time
> +	 * data_rate = pixel_clock * bit_per_pixel * mipi_ratio / num_lanes;
> +	 */
> +	pixel_clock = dsi->vm.pixelclock * 1000;
> +	htotal = dsi->vm.hactive + dsi->vm.hback_porch + dsi->vm.hfront_porch +
> +			dsi->vm.hsync_len;
> +	htotal_bits = htotal * bit_per_pixel;
> +
> +	overhead_cycles = T_LPX + T_HS_PREP + T_HS_ZERO + T_HS_TRAIL +
> +			T_HS_EXIT;
> +	overhead_bits = overhead_cycles * dsi->lanes * 8;
> +	total_bits = htotal_bits + overhead_bits;
> +
> +	dsi->data_rate = DIV_ROUND_UP_ULL(pixel_clock * total_bits,
> +					  htotal * dsi->lanes);
> +
> +	ret = clk_set_rate(dsi->hs_clk, dsi->data_rate);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to set data rate: %d\n", ret);
> +		goto err_refcount;
> +	}
> +
> +	phy_power_on(dsi->phy);
> +
> +	ret = clk_prepare_enable(dsi->engine_clk);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to enable engine clock: %d\n", ret);
> +		goto err_phy_power_off;
> +	}
> +
> +	ret = clk_prepare_enable(dsi->digital_clk);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to enable digital clock: %d\n", ret);
> +		goto err_disable_engine_clk;
> +	}
> +
> +	mtk_dsi_enable(dsi);
> +	mtk_dsi_reset_engine(dsi);
> +	mtk_dsi_phy_timconfig(dsi);
> +
> +	mtk_dsi_rxtx_control(dsi);
> +	mtk_dsi_ps_control_vact(dsi);
> +	mtk_dsi_set_vm_cmd(dsi);
> +	mtk_dsi_config_vdo_timing(dsi);
> +	mtk_dsi_set_interrupt_enable(dsi);
> +
> +	mtk_dsi_clk_ulp_mode_leave(dsi);
> +	mtk_dsi_lane0_ulp_mode_leave(dsi);
> +	mtk_dsi_clk_hs_mode(dsi, 0);
> +
> +	if (dsi->panel) {
> +		if (drm_panel_prepare(dsi->panel)) {
> +			DRM_ERROR("failed to prepare the panel\n");
> +			goto err_disable_digital_clk;
> +		}
> +	}
> +
> +	mtk_dsi_set_mode(dsi);
> +	mtk_dsi_clk_hs_mode(dsi, 1);
> +
> +	mtk_dsi_start(dsi);
> +
> +	return 0;
> +err_disable_digital_clk:
> +	clk_disable_unprepare(dsi->digital_clk);
> +err_disable_engine_clk:
> +	clk_disable_unprepare(dsi->engine_clk);
> +err_phy_power_off:
> +	phy_power_off(dsi->phy);
> +err_refcount:
> +	dsi->refcount--;
> +	return ret;
> +}
> +
>  static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
>  {
>  	if (WARN_ON(dsi->refcount == 0))
> @@ -578,6 +635,17 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
>  	if (--dsi->refcount != 0)
>  		return;
>  
> +	mtk_dsi_stop(dsi);
> +	if (!mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500)) {
> +		if (dsi->panel) {
> +			if (drm_panel_unprepare(dsi->panel)) {
> +				DRM_ERROR("failed to unprepare the panel\n");
> +				return;
> +			}
> +		}
> +	}
> +
> +	mtk_dsi_reset_engine(dsi);
>  	mtk_dsi_lane0_ulp_mode_enter(dsi);
>  	mtk_dsi_clk_ulp_mode_enter(dsi);
>  
> @@ -596,36 +664,24 @@ static void mtk_output_dsi_enable(struct mtk_dsi *dsi)
>  	if (dsi->enabled)
>  		return;
>  
> -	if (dsi->panel) {
> -		if (drm_panel_prepare(dsi->panel)) {
> -			DRM_ERROR("failed to setup the panel\n");
> -			return;
> -		}
> -	}
> -
>  	ret = mtk_dsi_poweron(dsi);
>  	if (ret < 0) {
>  		DRM_ERROR("failed to power on dsi\n");
>  		return;
>  	}
>  
> -	mtk_dsi_rxtx_control(dsi);
> -
> -	mtk_dsi_clk_ulp_mode_leave(dsi);
> -	mtk_dsi_lane0_ulp_mode_leave(dsi);
> -	mtk_dsi_clk_hs_mode(dsi, 0);
> -	mtk_dsi_set_mode(dsi);
> -
> -	mtk_dsi_ps_control_vact(dsi);
> -	mtk_dsi_config_vdo_timing(dsi);
> -	mtk_dsi_set_interrupt_enable(dsi);
> -
> -	mtk_dsi_set_mode(dsi);
> -	mtk_dsi_clk_hs_mode(dsi, 1);
> -
> -	mtk_dsi_start(dsi);
> +	if (dsi->panel) {
> +		if (drm_panel_enable(dsi->panel)) {
> +			DRM_ERROR("failed to enable the panel\n");
> +			goto err_dsi_power_off;
> +		}
> +	}
>  
>  	dsi->enabled = true;
> +
> +	return;
> +err_dsi_power_off:
> +	mtk_dsi_poweroff(dsi);
>  }
>  
>  static void mtk_output_dsi_disable(struct mtk_dsi *dsi)