From: A.Sunil Kamath Date: Thu, 16 Apr 2015 08:52:09 +0000 (+0530) Subject: drm/i915/skl: Implement enable/disable for Display C5 state. X-Git-Tag: firefly_0821_release~176^2~1470^2~54^2~96 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6b457d31ea0465fcadcf6d5044f5f71398954727;p=firefly-linux-kernel-4.4.55.git drm/i915/skl: Implement enable/disable for Display C5 state. This patch just implements the basic enable and disable functions of DC5 state which is needed for both SKL and BXT. Its important to load respective CSR program before calling enable, which anyways will happen as CSR program is executed during boot. DC5 is a power saving state where hardware dynamically disables power well 1 and the CDCLK PLL and saves the associated registers. DC5 can be entered when software allows it, power well 2 is disabled, and hardware detects that all pipes are disabled or pipe A is enabled with PSR active. Its better to configure display engine to have power well 2 disabled before getting into DC5 enable function. Hence rpm framework will have to ensure to check status of power well 2 before calling gen9_enable_dc5. Rather dc5 entry criteria should be decided based on power well 2 status. If disabled, then call gen9_enable_dc5. v2: Replace HAS_ with IS_ check as per Daniel's review comments v3: Cleared the bits dc5/dc6 enable of DC_STATE_EN register before setting them as per Satheesh's review comments. v4: call POSTING_READ for every write to a register to ensure that its written immediately. v5: Modified as per review comments from Imre. - Squashed register definitions into this patch. - Finetuned comments and functions. v6: Avoid redundant writes in gen9_set_dc_state_debugmask_memory_up function. v7: - Rebase to latest. - Move all runtime PM functions defined in intel_display.c to intel_runtime_pm.c. v8: Rebased to drm-intel-nightly. (Animesh) Issue: VIZ-2819 Signed-off-by: A.Sunil Kamath Signed-off-by: Damien Lespiau Signed-off-by: Animesh Manna Reviewed-by: Imre Deak Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index e35d7f29d7c2..1b31238fa531 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -7204,6 +7204,17 @@ enum skl_disp_power_wells { #define DC_STATE_EN_UPTO_DC5 (1<<0) #define DC_STATE_EN_DC9 (1<<3) +/* +* SKL DC +*/ +#define DC_STATE_EN 0x45504 +#define DC_STATE_EN_UPTO_DC5 (1<<0) +#define DC_STATE_EN_UPTO_DC6 (2<<0) +#define DC_STATE_EN_UPTO_DC5_DC6_MASK 0x3 + +#define DC_STATE_DEBUG 0x45520 +#define DC_STATE_DEBUG_MASK_MEMORY_UP (1<<1) + /* 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. */ #define D_COMP_HSW (MCHBAR_MIRROR_BASE_SNB + 0x5F0C) diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index ffbf9779c26d..839010a57a2b 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -419,14 +419,51 @@ void bxt_disable_dc9(struct drm_i915_private *dev_priv) POSTING_READ(DC_STATE_EN); } +static void gen9_set_dc_state_debugmask_memory_up( + struct drm_i915_private *dev_priv) +{ + uint32_t val; + + /* The below bit doesn't need to be cleared ever afterwards */ + val = I915_READ(DC_STATE_DEBUG); + if (!(val & DC_STATE_DEBUG_MASK_MEMORY_UP)) { + val |= DC_STATE_DEBUG_MASK_MEMORY_UP; + I915_WRITE(DC_STATE_DEBUG, val); + POSTING_READ(DC_STATE_DEBUG); + } +} + static void gen9_enable_dc5(struct drm_i915_private *dev_priv) { - /* TODO: Implementation to be done. */ + struct drm_device *dev = dev_priv->dev; + uint32_t val; + + WARN_ON(!IS_GEN9(dev)); + + DRM_DEBUG_KMS("Enabling DC5\n"); + + gen9_set_dc_state_debugmask_memory_up(dev_priv); + + val = I915_READ(DC_STATE_EN); + val &= ~DC_STATE_EN_UPTO_DC5_DC6_MASK; + val |= DC_STATE_EN_UPTO_DC5; + I915_WRITE(DC_STATE_EN, val); + POSTING_READ(DC_STATE_EN); } static void gen9_disable_dc5(struct drm_i915_private *dev_priv) { - /* TODO: Implementation to be done. */ + struct drm_device *dev = dev_priv->dev; + uint32_t val; + + WARN_ON(!IS_GEN9(dev)); + + DRM_DEBUG_KMS("Disabling DC5\n"); + + val = I915_READ(DC_STATE_EN); + val &= ~DC_STATE_EN_UPTO_DC5; + I915_WRITE(DC_STATE_EN, val); + POSTING_READ(DC_STATE_EN); } static void skl_set_power_well(struct drm_i915_private *dev_priv,