Re: [PATCH 4/7] drm/rockchip/dsi: correct phy parameter setting

[Sean Paul]

On Mon, Sep 18, 2017 at 05:05:36PM +0800, Nickey Yang wrote:
> As MIPI PHY document show, icpctrl<3..0> and lpfctrl<5..0>
> should depend on frequency,so fix it.
> 
> Signed-off-by: Nickey Yang <nickey.yang@xxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 70 +++++++++++++++++++---------------
>  1 file changed, 40 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> index 9265b7f..d5250e8 100644
> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> @@ -228,10 +228,10 @@
>  #define VCO_IN_CAP_CON_HIGH	(0x2 << 1)
>  #define REF_BIAS_CUR_SEL	BIT(0)
>  
> -#define CP_CURRENT_3MA		BIT(3)
> +#define CP_CURRENT_SEL(val)	((val) & 0xf)
>  #define CP_PROGRAM_EN		BIT(7)
>  #define LPF_PROGRAM_EN		BIT(6)
> -#define LPF_RESISTORS_20_KOHM	0
> +#define LPF_RESISTORS_SEL(val)	((val) & 0x3f)
>  
>  #define HSFREQRANGE_SEL(val)	(((val) & 0x3f) << 1)
>  
> @@ -340,32 +340,44 @@ enum dw_mipi_dsi_mode {
>  	DW_MIPI_DSI_VID_MODE,
>  };
>  
> -struct dphy_pll_testdin_map {
> +struct dphy_pll_parameter_map {
>  	unsigned int max_mbps;
> -	u8 testdin;
> +	u8 hsfreqrange;
> +	u8 icpctrl;
> +	u8 lpfctrl;
>  };
>  
>  /* The table is based on 27MHz DPHY pll reference clock. */
> -static const struct dphy_pll_testdin_map dptdin_map[] = {
> -	{  90, 0x00}, { 100, 0x10}, { 110, 0x20}, { 130, 0x01},
> -	{ 140, 0x11}, { 150, 0x21}, { 170, 0x02}, { 180, 0x12},
> -	{ 200, 0x22}, { 220, 0x03}, { 240, 0x13}, { 250, 0x23},
> -	{ 270, 0x04}, { 300, 0x14}, { 330, 0x05}, { 360, 0x15},
> -	{ 400, 0x25}, { 450, 0x06}, { 500, 0x16}, { 550, 0x07},
> -	{ 600, 0x17}, { 650, 0x08}, { 700, 0x18}, { 750, 0x09},
> -	{ 800, 0x19}, { 850, 0x29}, { 900, 0x39}, { 950, 0x0a},
> -	{1000, 0x1a}, {1050, 0x2a}, {1100, 0x3a}, {1150, 0x0b},
> -	{1200, 0x1b}, {1250, 0x2b}, {1300, 0x3b}, {1350, 0x0c},
> -	{1400, 0x1c}, {1450, 0x2c}, {1500, 0x3c}
> +static const struct dphy_pll_parameter_map dppa_map[] = {
> +	{  90, 0x00, 0x1 ,0x02}, { 100, 0x10 ,0x1, 0x02},

s/ ,/, /g

Switching icpctrl and lpfctrl values to hardcoded numbers obfuscates the value
they're being set to (ie: 3mA and 20kOhm). Can you please replace the hardcoded
values with #defines describing what the values mean?

> +	{ 110, 0x20, 0x1, 0x02}, { 130, 0x01, 0x1, 0x01},
> +	{ 140, 0x11, 0x1, 0x01}, { 150, 0x21, 0x1, 0x01},
> +	{ 170, 0x02, 0x9, 0x02}, { 180, 0x12, 0x9, 0x02},
> +	{ 200, 0x22, 0x9, 0x02}, { 220, 0x03, 0x2, 0x02},
> +	{ 240, 0x13, 0x2, 0x02}, { 250, 0x23, 0x2, 0x02},
> +	{ 270, 0x04, 0x9, 0x04}, { 300, 0x14, 0x9, 0x04},
> +	{ 330, 0x05, 0x1, 0x01}, { 360, 0x15, 0x1, 0x01},
> +	{ 400, 0x25, 0x1, 0x01}, { 450, 0x06, 0x6, 0x04},
> +	{ 500, 0x16, 0x6, 0x04}, { 550, 0x07, 0x6, 0x08},
> +	{ 600, 0x17, 0x6, 0x08}, { 650, 0x08, 0x6, 0x04},
> +	{ 700, 0x18, 0x6, 0x04}, { 750, 0x09, 0x6, 0x04},
> +	{ 800, 0x19, 0x6, 0x04}, { 850, 0x29, 0x6, 0x04},
> +	{ 900, 0x39, 0x6, 0x04}, { 950, 0x0a, 0xb, 0x10},
> +	{1000, 0x1a, 0xb, 0x10}, {1050, 0x2a, 0xb, 0x10},
> +	{1100, 0x3a, 0xb, 0x10}, {1150, 0x0b, 0xb, 0x08},
> +	{1200, 0x1b, 0xb, 0x08}, {1250, 0x2b, 0xb, 0x08},
> +	{1300, 0x3b, 0xb, 0x08}, {1350, 0x0c, 0xb, 0x08},
> +	{1400, 0x1c, 0xb, 0x08}, {1450, 0x2c, 0xb, 0x08},
> +	{1500, 0x3c, 0xb, 0x08}
>  };
>  
> -static int max_mbps_to_testdin(unsigned int max_mbps)
> +static int max_mbps_to_parameter(unsigned int max_mbps)
>  {
>  	int i;
>  
> -	for (i = 0; i < ARRAY_SIZE(dptdin_map); i++)
> -		if (dptdin_map[i].max_mbps > max_mbps)
> -			return dptdin_map[i].testdin;
> +	for (i = 0; i < ARRAY_SIZE(dppa_map); i++)
> +		if (dppa_map[i].max_mbps > max_mbps)
> +			return i;
>  
>  	return -EINVAL;
>  }
> @@ -447,16 +459,16 @@ static inline unsigned int ns2ui(struct dw_mipi_dsi *dsi, int ns)
>  
>  static int dw_mipi_dsi_phy_init(struct dw_mipi_dsi *dsi)
>  {
> -	int ret, testdin, vco, val;
> +	int ret, i, vco, val;
>  
>  	vco = (dsi->lane_mbps < 200) ? 0 : (dsi->lane_mbps + 100) / 200;
>  
> -	testdin = max_mbps_to_testdin(dsi->lane_mbps);
> -	if (testdin < 0) {
> +	i = max_mbps_to_parameter(dsi->lane_mbps);
> +	if (i < 0) {
>  		dev_err(dsi->dev,
> -			"failed to get testdin for %dmbps lane clock\n",
> +			"failed to get parameter for %dmbps lane clock\n",
>  			dsi->lane_mbps);
> -		return testdin;
> +		return i;
>  	}
>  
>  	/* Start by clearing PHY state */
> @@ -475,12 +487,10 @@ static int dw_mipi_dsi_phy_init(struct dw_mipi_dsi *dsi)
>  					 VCO_IN_CAP_CON_LOW |
>  					 REF_BIAS_CUR_SEL);
>  
> -	dw_mipi_dsi_phy_write(dsi, 0x11, CP_CURRENT_3MA);
> +	dw_mipi_dsi_phy_write(dsi, 0x11, CP_CURRENT_SEL(dppa_map[i].icpctrl));
>  	dw_mipi_dsi_phy_write(dsi, 0x12, CP_PROGRAM_EN | LPF_PROGRAM_EN |
> -					 LPF_RESISTORS_20_KOHM);
> -
> -	dw_mipi_dsi_phy_write(dsi, 0x44, HSFREQRANGE_SEL(testdin));
> -
> +					 LPF_RESISTORS_SEL(dppa_map[i].lpfctrl));
> +	dw_mipi_dsi_phy_write(dsi, 0x44, HSFREQRANGE_SEL(dppa_map[i].hsfreqrange));
>  	dw_mipi_dsi_phy_write(dsi, 0x17, INPUT_DIVIDER(dsi->input_div));
>  	dw_mipi_dsi_phy_write(dsi, 0x18, LOOP_DIV_LOW_SEL(dsi->feedback_div) |
>  					 LOW_PROGRAM_EN);
> @@ -547,7 +557,7 @@ static int dw_mipi_dsi_get_lane_bps(struct dw_mipi_dsi *dsi,
>  {
>  	unsigned long mpclk, tmp;
>  	unsigned int target_mbps = 1000;
> -	unsigned int max_mbps = dptdin_map[ARRAY_SIZE(dptdin_map) - 1].max_mbps;
> +	unsigned int max_mbps = dppa_map[ARRAY_SIZE(dppa_map) - 1].max_mbps;
>  	int bpp;
>  	int lanes = dsi->lanes;
>  	unsigned long best_freq = 0;
> -- 
> 1.9.1
> 
> 

-- 
Sean Paul, Software Engineer, Google / Chromium OS