diff mbox series

[15/26] drm/i915: Make M/N checks non-fuzzy

Message ID 20220503182242.18797-16-ville.syrjala@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: Make fastset not suck and allow seamless M/N changes | expand

Commit Message

Ville Syrjälä May 3, 2022, 6:22 p.m. UTC 
From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Now that we no longer fuzz M/N during fastset these should
match exctly.

TODO: we may need to do something for fastboot here as the
VBIOS/GOP may not compute M/N exactly the same way we do.
Though I guess we could try to match the VBIOS/GOP exactly.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 49 ++++----------------
 1 file changed, 8 insertions(+), 41 deletions(-)

Comments

Jani Nikula May 25, 2022, 11:03 a.m. UTC | #1 
On Tue, 03 May 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Now that we no longer fuzz M/N during fastset these should
> match exctly.
>
> TODO: we may need to do something for fastboot here as the
> VBIOS/GOP may not compute M/N exactly the same way we do.
> Though I guess we could try to match the VBIOS/GOP exactly.

I see that later patches change the M/N calculation, and that may be
enough.

But if GOP isn't consistent about this (I don't know), it's going to be
whack-a-mole if we get regression reports on not having fastboot.

Mmh. If we support seamless M/N change, could we do that on fastboot?

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

>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 49 ++++----------------
>  1 file changed, 8 insertions(+), 41 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 86971be92e57..198c6340a463 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -5832,47 +5832,15 @@ bool intel_fuzzy_clock_check(int clock1, int clock2)
>  	return false;
>  }
>  
> -static bool
> -intel_compare_m_n(unsigned int m, unsigned int n,
> -		  unsigned int m2, unsigned int n2,
> -		  bool exact)
> -{
> -	if (m == m2 && n == n2)
> -		return true;
> -
> -	if (exact || !m || !n || !m2 || !n2)
> -		return false;
> -
> -	BUILD_BUG_ON(DATA_LINK_M_N_MASK > INT_MAX);
> -
> -	if (n > n2) {
> -		while (n > n2) {
> -			m2 <<= 1;
> -			n2 <<= 1;
> -		}
> -	} else if (n < n2) {
> -		while (n < n2) {
> -			m <<= 1;
> -			n <<= 1;
> -		}
> -	}
> -
> -	if (n != n2)
> -		return false;
> -
> -	return intel_fuzzy_clock_check(m, m2);
> -}
> -
>  static bool
>  intel_compare_link_m_n(const struct intel_link_m_n *m_n,
> -		       const struct intel_link_m_n *m2_n2,
> -		       bool exact)
> +		       const struct intel_link_m_n *m2_n2)
>  {
>  	return m_n->tu == m2_n2->tu &&
> -		intel_compare_m_n(m_n->data_m, m_n->data_n,
> -				  m2_n2->data_m, m2_n2->data_n, exact) &&
> -		intel_compare_m_n(m_n->link_m, m_n->link_n,
> -				  m2_n2->link_m, m2_n2->link_n, exact);
> +		m_n->data_m == m2_n2->data_m &&
> +		m_n->data_n == m2_n2->data_n &&
> +		m_n->link_m == m2_n2->link_m &&
> +		m_n->link_n == m2_n2->link_n;
>  }
>  
>  static bool
> @@ -6066,8 +6034,7 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>  
>  #define PIPE_CONF_CHECK_M_N(name) do { \
>  	if (!intel_compare_link_m_n(&current_config->name, \
> -				    &pipe_config->name,\
> -				    !fastset)) { \
> +				    &pipe_config->name)) { \
>  		pipe_config_mismatch(fastset, crtc, __stringify(name), \
>  				     "(expected tu %i data %i/%i link %i/%i, " \
>  				     "found tu %i, data %i/%i link %i/%i)", \
> @@ -6114,9 +6081,9 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>   */
>  #define PIPE_CONF_CHECK_M_N_ALT(name, alt_name) do { \
>  	if (!intel_compare_link_m_n(&current_config->name, \
> -				    &pipe_config->name, !fastset) && \
> +				    &pipe_config->name) && \
>  	    !intel_compare_link_m_n(&current_config->alt_name, \
> -				    &pipe_config->name, !fastset)) { \
> +				    &pipe_config->name)) { \
>  		pipe_config_mismatch(fastset, crtc, __stringify(name), \
>  				     "(expected tu %i data %i/%i link %i/%i, " \
>  				     "or tu %i data %i/%i link %i/%i, " \
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 86971be92e57..198c6340a463 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -5832,47 +5832,15 @@  bool intel_fuzzy_clock_check(int clock1, int clock2)
 	return false;
 }
 
-static bool
-intel_compare_m_n(unsigned int m, unsigned int n,
-		  unsigned int m2, unsigned int n2,
-		  bool exact)
-{
-	if (m == m2 && n == n2)
-		return true;
-
-	if (exact || !m || !n || !m2 || !n2)
-		return false;
-
-	BUILD_BUG_ON(DATA_LINK_M_N_MASK > INT_MAX);
-
-	if (n > n2) {
-		while (n > n2) {
-			m2 <<= 1;
-			n2 <<= 1;
-		}
-	} else if (n < n2) {
-		while (n < n2) {
-			m <<= 1;
-			n <<= 1;
-		}
-	}
-
-	if (n != n2)
-		return false;
-
-	return intel_fuzzy_clock_check(m, m2);
-}
-
 static bool
 intel_compare_link_m_n(const struct intel_link_m_n *m_n,
-		       const struct intel_link_m_n *m2_n2,
-		       bool exact)
+		       const struct intel_link_m_n *m2_n2)
 {
 	return m_n->tu == m2_n2->tu &&
-		intel_compare_m_n(m_n->data_m, m_n->data_n,
-				  m2_n2->data_m, m2_n2->data_n, exact) &&
-		intel_compare_m_n(m_n->link_m, m_n->link_n,
-				  m2_n2->link_m, m2_n2->link_n, exact);
+		m_n->data_m == m2_n2->data_m &&
+		m_n->data_n == m2_n2->data_n &&
+		m_n->link_m == m2_n2->link_m &&
+		m_n->link_n == m2_n2->link_n;
 }
 
 static bool
@@ -6066,8 +6034,7 @@  intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 
 #define PIPE_CONF_CHECK_M_N(name) do { \
 	if (!intel_compare_link_m_n(&current_config->name, \
-				    &pipe_config->name,\
-				    !fastset)) { \
+				    &pipe_config->name)) { \
 		pipe_config_mismatch(fastset, crtc, __stringify(name), \
 				     "(expected tu %i data %i/%i link %i/%i, " \
 				     "found tu %i, data %i/%i link %i/%i)", \
@@ -6114,9 +6081,9 @@  intel_pipe_config_compare(const struct intel_crtc_state *current_config,
  */
 #define PIPE_CONF_CHECK_M_N_ALT(name, alt_name) do { \
 	if (!intel_compare_link_m_n(&current_config->name, \
-				    &pipe_config->name, !fastset) && \
+				    &pipe_config->name) && \
 	    !intel_compare_link_m_n(&current_config->alt_name, \
-				    &pipe_config->name, !fastset)) { \
+				    &pipe_config->name)) { \
 		pipe_config_mismatch(fastset, crtc, __stringify(name), \
 				     "(expected tu %i data %i/%i link %i/%i, " \
 				     "or tu %i data %i/%i link %i/%i, " \