Re: [PATCH v2 8/9] drm/i915/dsi: add support for gpio elements on CHV

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Mar 18, 2016 at 01:11:16PM +0200, Jani Nikula wrote:
> From: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
> 
> Add support for CHV gpio programming in DSI gpio elements.
> 
> XXX: I'd like to have a gpio table for chv as well as others.
> 
> [Rewritten by Jani, based on earlier work by Yogesh and Deepak.]
> 
> Signed-off-by: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
> Signed-off-by: Deepak M <m.deepak@intel.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 66 ++++++++++++++++++++++++++++++
>  1 file changed, 66 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> index ca48f7aa6a05..f8d3f608e9c8 100644
> --- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> +++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> @@ -97,6 +97,23 @@ static struct vlv_gpio_map vlv_gpio_table[] = {
>  	{ 11, IOSF_PORT_GPIO_NC, VLV_GPIO_NC_11_PCONF0 },
>  };
>  
> +#define CHV_MAX_GPIO_NUM_N		72
> +#define CHV_MAX_GPIO_NUM_SE		99
> +#define CHV_MAX_GPIO_NUM_SW		197
> +#define CHV_MIN_GPIO_NUM_SE		73
> +#define CHV_MIN_GPIO_NUM_SW		100
> +#define CHV_MIN_GPIO_NUM_E		198

Not sure why we need min+max for these.

I would probably just do something like:

#define CHV_GPIO_IDX_START_N	0
#define CHV_GPIO_IDX_START_SE	73
#define CHV_GPIO_IDX_START_SW	100
#define CHV_GPIO_IDX_START_SE	198

> +
> +#define CHV_PAD_FMLY_BASE		0x4400
> +#define CHV_PAD_FMLY_SIZE		0x400
> +#define CHV_PAD_CFG_0_1_REG_SIZE	0x8
> +#define CHV_PAD_CFG_REG_SIZE		0x4

I'd hide all the uglies that use these in macros like:

#define CHV_GPIO_PAD_CFG0(f, i)	(0x4400 + (f) * 0x400 + (i) * 8)
#define CHV_GPIO_PAD_CFG1(f, i)	(0x4400 + (f) * 0x400 + (i) * 8 + 4)

> +#define CHV_VBT_MAX_PINS_PER_FMLY	15
> +
> +#define CHV_GPIO_CFG_UNLOCK		0x00000000

Maybe just define the bit for documentation purpose and just write a
raw 0 to the register.

#define  CHV_GPIO_CFGLOCK	(1 << 31)

> +#define CHV_GPIO_CFG_HIZ		0x00008100

That's still not hiz.

#define  CHV_GPIO_GPIOCFG_GPIO	(0 << 8)
#define  CHV_GPIO_GPIOCFG_GPO	(1 << 8)
#define  CHV_GPIO_GPIOCFG_GPI	(2 << 8)
#define  CHV_GPIO_GPIOCFG_HIZ	(3 << 8)
#define  CHV_GPIO_GPIOEN	(1 << 15)

> +#define CHV_GPIO_CFG_TX_STATE_SHIFT	1

Maybe

#define  CHV_GPIO_GPIOTXSTATE(state)	((state) << 1)

> +
>  static inline enum port intel_dsi_seq_port_to_port(u8 port)
>  {
>  	return port ? PORT_C : PORT_A;
> @@ -241,6 +258,53 @@ static void vlv_exec_gpio(struct drm_i915_private *dev_priv,
>  	mutex_unlock(&dev_priv->sb_lock);
>  }
>  
> +static void chv_exec_gpio(struct drm_i915_private *dev_priv,
> +			  u8 gpio_source, u8 gpio_index, u8 action)
> +{
> +	u16 pconf0, padval;

cfg0, cfg1 to match the reg names. Or just drop them entirely since the
parametrized macros I suggested earlier would make thing very clear
without temp variables.

> +	u16 family_num;
> +	u8 port;
> +
> +	/* XXX: add a table similar to vlv for checking gpio indexes */

If we bother going that far, then I think we should just go for gpiolib
instead.

> +	if (dev_priv->vbt.dsi.seq_version >= 3) {
> +		if (gpio_index <= CHV_MAX_GPIO_NUM_N) {
> +			port = CHV_IOSF_PORT_GPIO_N;
> +		} else if (gpio_index <= CHV_MAX_GPIO_NUM_SE) {
> +			port = CHV_IOSF_PORT_GPIO_SE;
> +			gpio_index = gpio_index - CHV_MIN_GPIO_NUM_SE;
> +		} else if (gpio_index <= CHV_MAX_GPIO_NUM_SW) {
> +			port = CHV_IOSF_PORT_GPIO_SW;
> +			gpio_index = gpio_index - CHV_MIN_GPIO_NUM_SW;
> +		} else {
> +			port = CHV_IOSF_PORT_GPIO_E;
> +			gpio_index = gpio_index - CHV_MIN_GPIO_NUM_E;
> +		}
> +	} else if (dev_priv->vbt.dsi.seq_version == 2) {
> +		if (gpio_source == 0) {
> +			port = IOSF_PORT_GPIO_NC;
> +		} else if (gpio_source == 1) {
> +			port = IOSF_PORT_GPIO_SC;
> +		} else {
> +			DRM_DEBUG_KMS("unknown gpio source %u\n", gpio_source);
> +			return;
> +		}
> +	} else {
> +		port = IOSF_PORT_GPIO_NC;
> +	}
> +
> +	family_num = gpio_index / CHV_VBT_MAX_PINS_PER_FMLY;
> +	gpio_index = gpio_index - (family_num * CHV_VBT_MAX_PINS_PER_FMLY);

I'd still use % for clarity.

> +	padval = CHV_PAD_FMLY_BASE + (family_num * CHV_PAD_FMLY_SIZE) +
> +		(((u16)gpio_index) * CHV_PAD_CFG_0_1_REG_SIZE);
> +	pconf0 = padval + CHV_PAD_CFG_REG_SIZE;
> +
> +	mutex_lock(&dev_priv->sb_lock);
> +	vlv_iosf_sb_write(dev_priv, port, pconf0, CHV_GPIO_CFG_UNLOCK);
> +	vlv_iosf_sb_write(dev_priv, port, padval, CHV_GPIO_CFG_HIZ |
> +			  (action << CHV_GPIO_CFG_TX_STATE_SHIFT));
> +	mutex_unlock(&dev_priv->sb_lock);
> +}
> +
>  static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
>  {
>  	struct drm_device *dev = intel_dsi->base.base.dev;
> @@ -263,6 +327,8 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
>  
>  	if (IS_VALLEYVIEW(dev_priv))
>  		vlv_exec_gpio(dev_priv, gpio_source, gpio_index, action);
> +	else if (IS_CHERRYVIEW(dev_priv))
> +		chv_exec_gpio(dev_priv, gpio_source, gpio_index, action);
>  	else
>  		DRM_DEBUG_KMS("GPIO element not supported on this platform\n");
>  
> -- 
> 2.1.4

-- 
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx