From f3508947f6448c8709c8fb037eae1b93b08b2d86 Mon Sep 17 00:00:00 2001 From: Lucas De Marchi Date: Tue, 25 Jun 2019 10:54:11 -0700 Subject: [PATCH] drm/i915: rework reading pipe disable fuses MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This prepares to have possibly more than 3 pipes. I didn't want to continue the previous approach since the check for "are the disabled pipes the last ones" poses a combinatory explosion. We need that check because in several places of the code we have that assumption. If that ever becomes false in a new HW, other parts of the code would have to change. Now we start by considering we have info->num_pipes enabled and disable each pipe that is marked as disabled. Then it's a simple matter of checking if we have at least one pipe and that all the enabled ones are the first pipes, i.e. there are no holes in the bitmask. Cc: Jose Souza Cc: Ville Syrjälä Signed-off-by: Lucas De Marchi Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20190625175437.14840-3-lucas.demarchi@intel.com --- drivers/gpu/drm/i915/intel_device_info.c | 36 +++++++++--------------- 1 file changed, 13 insertions(+), 23 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c index 7135d8dc32a78..e64536e1fd1bd 100644 --- a/drivers/gpu/drm/i915/intel_device_info.c +++ b/drivers/gpu/drm/i915/intel_device_info.c @@ -929,35 +929,25 @@ void intel_device_info_runtime_init(struct drm_i915_private *dev_priv) } } else if (HAS_DISPLAY(dev_priv) && INTEL_GEN(dev_priv) >= 9) { u32 dfsm = I915_READ(SKL_DFSM); - u8 disabled_mask = 0; - bool invalid; - int num_bits; + u8 enabled_mask = BIT(info->num_pipes) - 1; if (dfsm & SKL_DFSM_PIPE_A_DISABLE) - disabled_mask |= BIT(PIPE_A); + enabled_mask &= ~BIT(PIPE_A); if (dfsm & SKL_DFSM_PIPE_B_DISABLE) - disabled_mask |= BIT(PIPE_B); + enabled_mask &= ~BIT(PIPE_B); if (dfsm & SKL_DFSM_PIPE_C_DISABLE) - disabled_mask |= BIT(PIPE_C); - - num_bits = hweight8(disabled_mask); - - switch (disabled_mask) { - case BIT(PIPE_A): - case BIT(PIPE_B): - case BIT(PIPE_A) | BIT(PIPE_B): - case BIT(PIPE_A) | BIT(PIPE_C): - invalid = true; - break; - default: - invalid = false; - } + enabled_mask &= ~BIT(PIPE_C); - if (num_bits > info->num_pipes || invalid) - DRM_ERROR("invalid pipe fuse configuration: 0x%x\n", - disabled_mask); + /* + * At least one pipe should be enabled and if there are + * disabled pipes, they should be the last ones, with no holes + * in the mask. + */ + if (enabled_mask == 0 || !is_power_of_2(enabled_mask + 1)) + DRM_ERROR("invalid pipe fuse configuration: enabled_mask=0x%x\n", + enabled_mask); else - info->num_pipes -= num_bits; + info->num_pipes = hweight8(enabled_mask); } /* Initialize slice/subslice/EU info */ -- 2.39.5