[v3] drm/i915: Add correct hw/sw config check for DSI encoder

Shobhit Kumar
2014-07-30T14:50:31Z

Check in vlv_crtc_clock_get if DPLL is enabled before calling dpio read.
It will not be enabled for DSI and avoid dpio read WARN dumps.

Absence of ->get_config was causing other WARN dumps as well. Update
dpll_hw_state as well correctly

v2: Address review comments by Daniel
- Check if DPLL is enabled rather than checking pipe output type
- set adjusted_mode->flags to 0 in compute_config rather than using
pipe_config->quirks
- Add helper function in intel_dsi_pll.c and use that in intel_dsi.c
- updated dpll_hw_state correctly
- Updated commit message and title

v3: Address review comments by Imre
- Proper masking of P1, M1 fields while computing divisors
- assert in case of bpp mismatch
- guard for divide by 0 while computing pclk
- Use ARRAY_SIZE instead of direct calculation

Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 4 ++
drivers/gpu/drm/i915/intel_dsi.c | 21 +++++++++-
drivers/gpu/drm/i915/intel_dsi.h | 1 +
drivers/gpu/drm/i915/intel_dsi_pll.c | 81 ++++++++++++++++++++++++++++++++++++
4 files changed, 106 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f3d6cc3..883af0b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6195,6 +6195,10 @@ static void vlv_crtc_clock_get(struct intel_crtc *crtc,
u32 mdiv;
int refclk = 100000;

+ /* In case of MIPI DPLL will not even be used */
+ if (!(pipe_config->dpll_hw_state.dpll & DPLL_VCO_ENABLE))
+ return;
+
mutex_lock(&dev_priv->dpio_lock);
mdiv = vlv_dpio_read(dev_priv, pipe, VLV_PLL_DW3(pipe));
mutex_unlock(&dev_priv->dpio_lock);
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 09e1caf..670c29a 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -92,6 +92,9 @@ static bool intel_dsi_compute_config(struct intel_encoder *encoder,
if (fixed_mode)
intel_fixed_panel_mode(fixed_mode, adjusted_mode);

+ /* DSI uses short packets for sync events, so clear mode flags for DSI */
+ adjusted_mode->flags = 0;
+
if (intel_dsi->dev.dev_ops->mode_fixup)
return intel_dsi->dev.dev_ops->mode_fixup(&intel_dsi->dev,
mode, adjusted_mode);
@@ -179,6 +182,10 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder)
tmp |= DPLL_REFA_CLK_ENABLE_VLV;
I915_WRITE(DPLL(pipe), tmp);

+ /* update the hw state for DPLL */
+ intel_crtc->config.dpll_hw_state.dpll = DPLL_INTEGRATED_CLOCK_VLV |
+ DPLL_REFA_CLK_ENABLE_VLV;
+
tmp = I915_READ(DSPCLK_GATE_D);
tmp |= DPOUNIT_CLOCK_GATE_DISABLE;
I915_WRITE(DSPCLK_GATE_D, tmp);
@@ -359,9 +366,21 @@ static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
static void intel_dsi_get_config(struct intel_encoder *encoder,
struct intel_crtc_config *pipe_config)
{
+ u32 pclk;
DRM_DEBUG_KMS("\n");

- /* XXX: read flags, set to adjusted_mode */
+ /*
+ * DPLL_MD is not used in case of DSI, reading will get some default value
+ * set dpll_md = 0
+ */
+ pipe_config->dpll_hw_state.dpll_md = 0;
+
+ pclk = vlv_get_dsi_pclk(encoder, pipe_config->pipe_bpp);
+ if (!pclk)
+ return;
+
+ pipe_config->adjusted_mode.crtc_clock = pclk;
+ pipe_config->port_clock = pclk;
}

static enum drm_mode_status
diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
index 31db33d..fd51867 100644
--- a/drivers/gpu/drm/i915/intel_dsi.h
+++ b/drivers/gpu/drm/i915/intel_dsi.h
@@ -132,6 +132,7 @@ static inline struct intel_dsi *enc_to_intel_dsi(struct drm_encoder *encoder)

extern void vlv_enable_dsi_pll(struct intel_encoder *encoder);
extern void vlv_disable_dsi_pll(struct intel_encoder *encoder);
+extern u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp);

extern struct intel_dsi_dev_ops vbt_generic_dsi_display_ops;

diff --git a/drivers/gpu/drm/i915/intel_dsi_pll.c b/drivers/gpu/drm/i915/intel_dsi_pll.c
index ba79ec1..d8bb1ea 100644
--- a/drivers/gpu/drm/i915/intel_dsi_pll.c
+++ b/drivers/gpu/drm/i915/intel_dsi_pll.c
@@ -298,3 +298,84 @@ void vlv_disable_dsi_pll(struct intel_encoder *encoder)

mutex_unlock(&dev_priv->dpio_lock);
}
+
+static void assert_bpp_mismatch(int pixel_format, int pipe_bpp)
+{
+ int bpp;
+
+ switch (pixel_format) {
+ default:
+ case VID_MODE_FORMAT_RGB888:
+ case VID_MODE_FORMAT_RGB666_LOOSE:
+ bpp = 24;
+ break;
+ case VID_MODE_FORMAT_RGB666:
+ bpp = 18;
+ break;
+ case VID_MODE_FORMAT_RGB565:
+ bpp = 16;
+ break;
+ }
+
+ WARN(bpp != pipe_bpp,
+ "bpp match assertion failure (expected %d, current %d)\n",
+ bpp, pipe_bpp);
+}
+
+u32 vlv_get_dsi_pclk(struct intel_encoder *encoder, int pipe_bpp)
+{
+ struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+ u32 dsi_clock, pclk;
+ u32 pll_ctl, pll_div;
+ u32 m = 0, p = 0;
+ int refclk = 25000;
+ int i;
+
+ DRM_DEBUG_KMS("\n");
+
+ mutex_lock(&dev_priv->dpio_lock);
+ pll_ctl = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_CONTROL);
+ pll_div = vlv_cck_read(dev_priv, CCK_REG_DSI_PLL_DIVIDER);
+ mutex_unlock(&dev_priv->dpio_lock);
+
+ /* mask out other bits and extract the P1 divisor */
+ pll_ctl &= DSI_PLL_P1_POST_DIV_MASK;
+ pll_ctl = pll_ctl >> (DSI_PLL_P1_POST_DIV_SHIFT - 2);
+
+ /* mask out the other bits and extract the M1 divisor */
+ pll_div &= DSI_PLL_M1_DIV_MASK;
+ pll_div = pll_div >> DSI_PLL_M1_DIV_SHIFT;
+
+ while (pll_ctl) {
+ pll_ctl = pll_ctl >> 1;
+ p++;
+ }
+ p--;
+
+ if (!p) {
+ DRM_ERROR("wrong P1 divisor\n");
+ return 0;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(lfsr_converts); i++) {
+ if (lfsr_converts[i] == pll_div)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(lfsr_converts)) {
+ DRM_ERROR("wrong m_seed programmed\n");
+ return 0;
+ }
+
+ m = i + 62;
+
+ dsi_clock = (m * refclk) / p;
+
+ /* pixel_format and pipe_bpp should agree */
+ assert_bpp_mismatch(intel_dsi->pixel_format, pipe_bpp);
+
+ pclk = DIV_ROUND_CLOSEST(dsi_clock * intel_dsi->lane_count, pipe_bpp);
+
+ return pclk;
+}
--
1.9.1