[PATCH v6 24/49] drm/i915/bxt: DDI Hotplug interrupt setup

Imre Deak
2015-03-27T12:54:16Z

From: Shashank Sharma <shashank.sharma@intel.com>

In BXT, DDI hotplug control has been moved to CPU from PCH.
This patch adds a new IRQ setup function for BXT which:
1. Checks which HPD ports are requested to be enabled by encoders.
2. Enables those ports in the hot plug control register.
3. Un-masks these port interrupts in the IMR register.
4. Enables these port interrupts in the IER register.

V3: Kept the default HPD filter count to default (500 us) as per
satheesh's comment
v4: Remove unused HPD filter defines (Damien)
v5: warn if trying to setup HPD on port A (imre)
v6: fix order of definitions for register bitfields (Daniel)

Reviewed-by: Satheeshakrishna M <satheeshakrishna.m@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com> (v4)
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
drivers/gpu/drm/i915/i915_irq.c | 49 ++++++++++++++++++++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_reg.h | 25 ++++++++++++++++++++-
2 files changed, 72 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 14ecb4d..d09b389 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -88,6 +88,12 @@ static const u32 hpd_status_i915[HPD_NUM_PINS] = { /* i915 and valleyview are th
[HPD_PORT_D] = PORTD_HOTPLUG_INT_STATUS
};

+/* BXT hpd list */
+static const u32 hpd_bxt[] = {
+ [HPD_PORT_B] = BXT_DE_PORT_HP_DDIB,
+ [HPD_PORT_C] = BXT_DE_PORT_HP_DDIC
+};
+
/* IIR can theoretically queue up two events. Be paranoid. */
#define GEN8_IRQ_RESET_NDX(type, which) do { \
I915_WRITE(GEN8_##type##_IMR(which), 0xffffffff); \
@@ -3178,6 +3184,44 @@ static void ibx_hpd_irq_setup(struct drm_device *dev)
I915_WRITE(PCH_PORT_HOTPLUG, hotplug);
}

+static void bxt_hpd_irq_setup(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ struct intel_encoder *intel_encoder;
+ u32 hotplug_port = 0;
+ u32 hotplug_ctrl;
+
+ /* Now, enable HPD */
+ list_for_each_entry(intel_encoder, &mode_config->encoder_list,
+ base.head) {
+ if (dev_priv->hpd_stats[intel_encoder->hpd_pin].hpd_mark
+ == HPD_ENABLED)
+ hotplug_port |= hpd_bxt[intel_encoder->hpd_pin];
+ }
+
+ /* Mask all HPD control bits */
+ hotplug_ctrl = I915_READ(BXT_HOTPLUG_CTL) & ~BXT_HOTPLUG_CTL_MASK;
+
+ /* Enable requested port in hotplug control */
+ /* TODO: implement (short) HPD support on port A */
+ WARN_ON_ONCE(hotplug_port & BXT_DE_PORT_HP_DDIA);
+ if (hotplug_port & BXT_DE_PORT_HP_DDIB)
+ hotplug_ctrl |= BXT_DDIB_HPD_ENABLE;
+ if (hotplug_port & BXT_DE_PORT_HP_DDIC)
+ hotplug_ctrl |= BXT_DDIC_HPD_ENABLE;
+ I915_WRITE(BXT_HOTPLUG_CTL, hotplug_ctrl);
+
+ /* Unmask DDI hotplug in IMR */
+ hotplug_ctrl = I915_READ(GEN8_DE_PORT_IMR) & ~hotplug_port;
+ I915_WRITE(GEN8_DE_PORT_IMR, hotplug_ctrl);
+
+ /* Enable DDI hotplug in IER */
+ hotplug_ctrl = I915_READ(GEN8_DE_PORT_IER) | hotplug_port;
+ I915_WRITE(GEN8_DE_PORT_IER, hotplug_ctrl);
+ POSTING_READ(GEN8_DE_PORT_IER);
+}
+
static void ibx_irq_postinstall(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -4298,7 +4342,10 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
dev->driver->irq_uninstall = gen8_irq_uninstall;
dev->driver->enable_vblank = gen8_enable_vblank;
dev->driver->disable_vblank = gen8_disable_vblank;
- dev_priv->display.hpd_irq_setup = ibx_hpd_irq_setup;
+ if (HAS_PCH_SPLIT(dev))
+ dev_priv->display.hpd_irq_setup = ibx_hpd_irq_setup;
+ else
+ dev_priv->display.hpd_irq_setup = bxt_hpd_irq_setup;
} else if (HAS_PCH_SPLIT(dev)) {
dev->driver->irq_handler = ironlake_irq_handler;
dev->driver->irq_preinstall = ironlake_irq_reset;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 6a5ade6..a082d7d 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5240,10 +5240,16 @@ enum skl_disp_power_wells {
#define GEN8_DE_PORT_IMR 0x44444
#define GEN8_DE_PORT_IIR 0x44448
#define GEN8_DE_PORT_IER 0x4444c
-#define GEN8_PORT_DP_A_HOTPLUG (1 << 3)
#define GEN9_AUX_CHANNEL_D (1 << 27)
#define GEN9_AUX_CHANNEL_C (1 << 26)
#define GEN9_AUX_CHANNEL_B (1 << 25)
+#define BXT_DE_PORT_HP_DDIC (1 << 5)
+#define BXT_DE_PORT_HP_DDIB (1 << 4)
+#define BXT_DE_PORT_HP_DDIA (1 << 3)
+#define BXT_DE_PORT_HOTPLUG_MASK (BXT_DE_PORT_HP_DDIA | \
+ BXT_DE_PORT_HP_DDIB | \
+ BXT_DE_PORT_HP_DDIC)
+#define GEN8_PORT_DP_A_HOTPLUG (1 << 3)
#define GEN8_AUX_CHANNEL_A (1 << 0)

#define GEN8_DE_MISC_ISR 0x44460
@@ -5257,6 +5263,23 @@ enum skl_disp_power_wells {
#define GEN8_PCU_IIR 0x444e8
#define GEN8_PCU_IER 0x444ec

+/* BXT hotplug control */
+#define BXT_HOTPLUG_CTL 0xC4030
+#define BXT_DDIA_HPD_ENABLE (1 << 28)
+#define BXT_DDIC_HPD_ENABLE (1 << 12)
+#define BXT_DDIB_HPD_ENABLE (1 << 4)
+#define BXT_HOTPLUG_CTL_MASK (BXT_DDIA_HPD_ENABLE | \
+ BXT_DDIB_HPD_ENABLE | \
+ BXT_DDIC_HPD_ENABLE)
+
+/* Hot plug status */
+#define BXT_DDIA_HPD_STATUS (3 << 24)
+#define BXT_DDIC_HPD_STATUS (3 << 8)
+#define BXT_DDIB_HPD_STATUS (3 << 0)
+#define BXT_HPD_STATUS_MASK (BXT_DDIA_HPD_STATUS | \
+ BXT_DDIB_HPD_STATUS | \
+ BXT_DDIC_HPD_STATUS)
+
#define ILK_DISPLAY_CHICKEN2 0x42004
/* Required on all Ironlake and Sandybridge according to the B-Spec. */
#define ILK_ELPIN_409_SELECT (1 << 25)
--
2.1.0