Skip to content

Commit

Permalink
drm/i915: Add some CHV DPIO lane power state asserts
Browse files Browse the repository at this point in the history
Add some checks that the state of the DPIO lanes is more or less what we
expect based on the overrides.

The hardware only provides two bits per channel indicating whether all
or some of the lanes are powered down, so we can't do an exact check.

Additionally, CL2 powering down before we can check it adds another
twist. To work around this we simply check for the 0 value of the
CL2 register (which is what we get when it's powered down) and
adjust our expectations.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
  • Loading branch information
Ville Syrjälä authored and Daniel Vetter committed Sep 1, 2015
1 parent a8f327f commit 6669e39
Show file tree
Hide file tree
Showing 2 changed files with 62 additions and 0 deletions.
8 changes: 8 additions & 0 deletions drivers/gpu/drm/i915/i915_reg.h
Original file line number Diff line number Diff line change
Expand Up @@ -1099,6 +1099,12 @@ enum skl_disp_power_wells {
#define DPIO_CHV_INT_LOCK_THRESHOLD_SEL_COARSE 1 /* 1: coarse & 0 : fine */
#define CHV_PLL_DW9(ch) _PIPE(ch, _CHV_PLL_DW9_CH0, _CHV_PLL_DW9_CH1)

#define _CHV_CMN_DW0_CH0 0x8100
#define DPIO_ALLDL_POWERDOWN_SHIFT_CH0 19
#define DPIO_ANYDL_POWERDOWN_SHIFT_CH0 18
#define DPIO_ALLDL_POWERDOWN (1 << 1)
#define DPIO_ANYDL_POWERDOWN (1 << 0)

#define _CHV_CMN_DW5_CH0 0x8114
#define CHV_BUFRIGHTENA1_DISABLE (0 << 20)
#define CHV_BUFRIGHTENA1_NORMAL (1 << 20)
Expand Down Expand Up @@ -1135,6 +1141,8 @@ enum skl_disp_power_wells {

#define _CHV_CMN_DW19_CH0 0x814c
#define _CHV_CMN_DW6_CH1 0x8098
#define DPIO_ALLDL_POWERDOWN_SHIFT_CH1 30 /* CL2 DW6 only */
#define DPIO_ANYDL_POWERDOWN_SHIFT_CH1 29 /* CL2 DW6 only */
#define DPIO_DYNPWRDOWNEN_CH1 (1 << 28) /* CL2 DW6 only */
#define CHV_CMN_USEDCLKCHANNEL (1 << 13)

Expand Down
54 changes: 54 additions & 0 deletions drivers/gpu/drm/i915/intel_runtime_pm.c
Original file line number Diff line number Diff line change
Expand Up @@ -1042,6 +1042,58 @@ static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
phy, dev_priv->chv_phy_control);
}

static void assert_chv_phy_powergate(struct drm_i915_private *dev_priv, enum dpio_phy phy,
enum dpio_channel ch, bool override, unsigned int mask)
{
enum pipe pipe = phy == DPIO_PHY0 ? PIPE_A : PIPE_C;
u32 reg, val, expected, actual;

if (ch == DPIO_CH0)
reg = _CHV_CMN_DW0_CH0;
else
reg = _CHV_CMN_DW6_CH1;

mutex_lock(&dev_priv->sb_lock);
val = vlv_dpio_read(dev_priv, pipe, reg);
mutex_unlock(&dev_priv->sb_lock);

/*
* This assumes !override is only used when the port is disabled.
* All lanes should power down even without the override when
* the port is disabled.
*/
if (!override || mask == 0xf) {
expected = DPIO_ALLDL_POWERDOWN | DPIO_ANYDL_POWERDOWN;
/*
* If CH1 common lane is not active anymore
* (eg. for pipe B DPLL) the entire channel will
* shut down, which causes the common lane registers
* to read as 0. That means we can't actually check
* the lane power down status bits, but as the entire
* register reads as 0 it's a good indication that the
* channel is indeed entirely powered down.
*/
if (ch == DPIO_CH1 && val == 0)
expected = 0;
} else if (mask != 0x0) {
expected = DPIO_ANYDL_POWERDOWN;
} else {
expected = 0;
}

if (ch == DPIO_CH0)
actual = val >> DPIO_ANYDL_POWERDOWN_SHIFT_CH0;
else
actual = val >> DPIO_ANYDL_POWERDOWN_SHIFT_CH1;
actual &= DPIO_ALLDL_POWERDOWN | DPIO_ANYDL_POWERDOWN;

WARN(actual != expected,
"Unexpected DPIO lane power down: all %d, any %d. Expected: all %d, any %d. (0x%x = 0x%08x)\n",
!!(actual & DPIO_ALLDL_POWERDOWN), !!(actual & DPIO_ANYDL_POWERDOWN),
!!(expected & DPIO_ALLDL_POWERDOWN), !!(expected & DPIO_ANYDL_POWERDOWN),
reg, val);
}

bool chv_phy_powergate_ch(struct drm_i915_private *dev_priv, enum dpio_phy phy,
enum dpio_channel ch, bool override)
{
Expand Down Expand Up @@ -1094,6 +1146,8 @@ void chv_phy_powergate_lanes(struct intel_encoder *encoder,
DRM_DEBUG_KMS("Power gating DPIO PHY%d CH%d lanes 0x%x (PHY_CONTROL=0x%08x)\n",
phy, ch, mask, dev_priv->chv_phy_control);

assert_chv_phy_powergate(dev_priv, phy, ch, override, mask);

mutex_unlock(&power_domains->lock);
}

Expand Down

0 comments on commit 6669e39

Please sign in to comment.