[Intel-gfx] [PATCH 11/12] drm/i915: Extract DIMM info on cnl+

Jani Nikula jani.nikula at linux.intel.com
Tue Mar 5 16:16:57 UTC 2019


On Mon, 25 Feb 2019, Ville Syrjala <ville.syrjala at linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
> We'll need information about the memory configuration on cnl+ too.
> Extend the code to parse the slightly changed register layout.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c | 69 ++++++++++++++++++++++++---------
>  drivers/gpu/drm/i915/i915_reg.h | 17 +++++++-
>  2 files changed, 66 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index e3aafe2bf3b7..95361814b531 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1095,17 +1095,43 @@ static int skl_get_dimm_ranks(u16 val)
>  	if (skl_get_dimm_size(val) == 0)
>  		return 0;
>  
> -	switch (val & SKL_DRAM_RANK_MASK) {
> -	case SKL_DRAM_RANK_SINGLE:
> -	case SKL_DRAM_RANK_DUAL:
> -		val = (val & SKL_DRAM_RANK_MASK) >> SKL_DRAM_RANK_SHIFT;
> -		return val + 1;
> +	val = (val & SKL_DRAM_RANK_MASK) >> SKL_DRAM_RANK_SHIFT;
> +
> +	return val + 1;

This part is a bit out of place. Rebase fail?

> +}
> +
> +static int cnl_get_dimm_size(u16 val)
> +{
> +	return (val & CNL_DRAM_SIZE_MASK) / 2;

Multiples of 0.5 GB... what an odd unit. What if there's an odd value?

> +}
> +
> +static int cnl_get_dimm_width(u16 val)
> +{
> +	if (cnl_get_dimm_size(val) == 0)
> +		return 0;
> +
> +	switch (val & CNL_DRAM_WIDTH_MASK) {
> +	case CNL_DRAM_WIDTH_X8:
> +	case CNL_DRAM_WIDTH_X16:
> +	case CNL_DRAM_WIDTH_X32:
> +		val = (val & CNL_DRAM_WIDTH_MASK) >> CNL_DRAM_WIDTH_SHIFT;
> +		return 8 << val;
>  	default:
>  		MISSING_CASE(val);
>  		return 0;
>  	}
>  }
>  
> +static int cnl_get_dimm_ranks(u16 val)
> +{
> +	if (cnl_get_dimm_size(val) == 0)
> +		return 0;
> +
> +	val = (val & CNL_DRAM_RANK_MASK) >> CNL_DRAM_RANK_SHIFT;
> +
> +	return val + 1;
> +}
> +
>  static bool
>  skl_is_16gb_dimm(const struct dram_dimm_info *dimm)
>  {
> @@ -1113,12 +1139,19 @@ skl_is_16gb_dimm(const struct dram_dimm_info *dimm)
>  }
>  
>  static void
> -skl_dram_get_dimm_info(struct dram_dimm_info *dimm,
> +skl_dram_get_dimm_info(struct drm_i915_private *dev_priv,
> +		       struct dram_dimm_info *dimm,
>  		       int channel, char dimm_name, u16 val)
>  {
> -	dimm->size = skl_get_dimm_size(val);
> -	dimm->width = skl_get_dimm_width(val);
> -	dimm->ranks = skl_get_dimm_ranks(val);
> +	if (INTEL_GEN(dev_priv) >= 10) {
> +		dimm->size = cnl_get_dimm_size(val);
> +		dimm->width = cnl_get_dimm_width(val);
> +		dimm->ranks = cnl_get_dimm_ranks(val);
> +	} else {
> +		dimm->size = skl_get_dimm_size(val);
> +		dimm->width = skl_get_dimm_width(val);
> +		dimm->ranks = skl_get_dimm_ranks(val);
> +	}
>  
>  	DRM_DEBUG_KMS("CH%d DIMM %c size: %d GB, width: X%d, ranks: %d, 16Gb DIMMs: %s\n",
>  		      channel, dimm_name, dimm->size, dimm->width, dimm->ranks,
> @@ -1126,11 +1159,14 @@ skl_dram_get_dimm_info(struct dram_dimm_info *dimm,
>  }
>  
>  static int
> -skl_dram_get_channel_info(struct dram_channel_info *ch,
> +skl_dram_get_channel_info(struct drm_i915_private *dev_priv,
> +			  struct dram_channel_info *ch,
>  			  int channel, u32 val)
>  {
> -	skl_dram_get_dimm_info(&ch->dimm_l, channel, 'L', val & 0xffff);
> -	skl_dram_get_dimm_info(&ch->dimm_s, channel, 'S', val >> 16);
> +	skl_dram_get_dimm_info(dev_priv, &ch->dimm_l,
> +			       channel, 'L', val & 0xffff);
> +	skl_dram_get_dimm_info(dev_priv, &ch->dimm_s,
> +			       channel, 'S', val >> 16);
>  
>  	if (ch->dimm_l.size == 0 && ch->dimm_s.size == 0) {
>  		DRM_DEBUG_KMS("CH%d not populated\n", channel);
> @@ -1172,12 +1208,12 @@ skl_dram_get_channels_info(struct drm_i915_private *dev_priv)
>  	int ret;
>  
>  	val = I915_READ(SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
> -	ret = skl_dram_get_channel_info(&ch0, 0, val);
> +	ret = skl_dram_get_channel_info(dev_priv, &ch0, 0, val);
>  	if (ret == 0)
>  		dram_info->num_channels++;
>  
>  	val = I915_READ(SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
> -	ret = skl_dram_get_channel_info(&ch1, 1, val);
> +	ret = skl_dram_get_channel_info(dev_priv, &ch1, 1, val);
>  	if (ret == 0)
>  		dram_info->num_channels++;
>  
> @@ -1369,13 +1405,10 @@ intel_get_dram_info(struct drm_i915_private *dev_priv)
>  	if (INTEL_GEN(dev_priv) < 9)
>  		return;
>  
> -	/* Need to calculate bandwidth only for Gen9 */
>  	if (IS_GEN9_LP(dev_priv))
>  		ret = bxt_get_dram_info(dev_priv);
> -	else if (IS_GEN(dev_priv, 9))
> -		ret = skl_get_dram_info(dev_priv);
>  	else
> -		ret = skl_dram_get_channels_info(dev_priv);
> +		ret = skl_get_dram_info(dev_priv);

The part that's hidden here is the use of the common parts in
skl_get_dram_info() and in particular
SKL_MEMORY_FREQ_MULTIPLIER_HZ. Spec says "The value is given in units of
133.33 MHz". But it says the same for SKL too. What am I missing?

Tentative Reviewed-by: Jani Nikula <jani.nikula at intel.com>

>  	if (ret)
>  		return;
>  
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 730bb1917fd1..b35b0220764f 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -9875,8 +9875,21 @@ enum skl_power_gate {
>  #define  SKL_DRAM_WIDTH_X32			(0x2 << 8)
>  #define  SKL_DRAM_RANK_MASK			(0x1 << 10)
>  #define  SKL_DRAM_RANK_SHIFT			10
> -#define  SKL_DRAM_RANK_SINGLE			(0x0 << 10)
> -#define  SKL_DRAM_RANK_DUAL			(0x1 << 10)
> +#define  SKL_DRAM_RANK_1			(0x0 << 10)
> +#define  SKL_DRAM_RANK_2			(0x1 << 10)
> +#define  SKL_DRAM_RANK_MASK			(0x1 << 10)
> +#define  CNL_DRAM_SIZE_MASK			0x7F
> +#define  CNL_DRAM_WIDTH_MASK			(0x3 << 7)
> +#define  CNL_DRAM_WIDTH_SHIFT			7
> +#define  CNL_DRAM_WIDTH_X8			(0x0 << 7)
> +#define  CNL_DRAM_WIDTH_X16			(0x1 << 7)
> +#define  CNL_DRAM_WIDTH_X32			(0x2 << 7)
> +#define  CNL_DRAM_RANK_MASK			(0x3 << 9)
> +#define  CNL_DRAM_RANK_SHIFT			9
> +#define  CNL_DRAM_RANK_1			(0x0 << 9)
> +#define  CNL_DRAM_RANK_2			(0x1 << 9)
> +#define  CNL_DRAM_RANK_3			(0x2 << 9)
> +#define  CNL_DRAM_RANK_4			(0x3 << 9)
>  
>  /* Please see hsw_read_dcomp() and hsw_write_dcomp() before using this register,
>   * since on HSW we can't write to it using I915_WRITE. */

-- 
Jani Nikula, Intel Open Source Graphics Center


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