On Tue, 03 May 2022, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote:
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> 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@xxxxxxxxx>
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> ---
> 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(¤t_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(¤t_config->name, \
> - &pipe_config->name, !fastset) && \
> + &pipe_config->name) && \
> !intel_compare_link_m_n(¤t_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, " \
--
Jani Nikula, Intel Open Source Graphics Center
