drm/i915: add support for mPHY destination on intel_sbi_{read, write}

This way we should be able to write mPHY registers using the Sideband
Interface in the next commit. Also fixed some syntax oddities in the
related code.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 40 insertions, 34 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 79589bbff3d..8513e1cd221 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -382,6 +382,11 @@ enum intel_pch {
         PCH_LPT,        /* Lynxpoint PCH */
 };
 
+enum intel_sbi_destination {
+        SBI_ICLK,
+        SBI_MPHY,
+};
+
 #define QUIRK_PIPEA_FORCE (1<<0)
 #define QUIRK_LVDS_SSC_DISABLE (1<<1)
 #define QUIRK_INVERT_BRIGHTNESS (1<<2)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 97fbd9d1823..0760425c892 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4534,6 +4534,10 @@
 #define SBI_ADDR                        0xC6000
 #define SBI_DATA                        0xC6004
 #define SBI_CTL_STAT                    0xC6008
+#define  SBI_CTL_DEST_ICLK              (0x0<<16)
+#define  SBI_CTL_DEST_MPHY              (0x1<<16)
+#define  SBI_CTL_OP_IORD                (0x2<<8)
+#define  SBI_CTL_OP_IOWR                (0x3<<8)
 #define  SBI_CTL_OP_CRRD                (0x6<<8)
 #define  SBI_CTL_OP_CRWR                (0x7<<8)
 #define  SBI_RESPONSE_FAIL              (0x1<<1)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 41e2d9508ef..64993ecacf9 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1506,24 +1506,26 @@ static void intel_disable_pll(struct drm_i915_private *dev_priv, enum pipe pipe)
 
 /* SBI access */
 static void
-intel_sbi_write(struct drm_i915_private *dev_priv, u16 reg, u32 value)
+intel_sbi_write(struct drm_i915_private *dev_priv, u16 reg, u32 value,
+                enum intel_sbi_destination destination)
 {
         unsigned long flags;
+        u32 tmp;
 
         spin_lock_irqsave(&dev_priv->dpio_lock, flags);
-        if (wait_for((I915_READ(SBI_CTL_STAT) & SBI_BUSY) == 0,
-                                100)) {
+        if (wait_for((I915_READ(SBI_CTL_STAT) & SBI_BUSY) == 0, 100)) {
                 DRM_ERROR("timeout waiting for SBI to become ready\n");
                 goto out_unlock;
         }
 
-        I915_WRITE(SBI_ADDR,
-                        (reg << 16));
-        I915_WRITE(SBI_DATA,
-                        value);
-        I915_WRITE(SBI_CTL_STAT,
-                        SBI_BUSY |
-                        SBI_CTL_OP_CRWR);
+        I915_WRITE(SBI_ADDR, (reg << 16));
+        I915_WRITE(SBI_DATA, value);
+
+        if (destination == SBI_ICLK)
+                tmp = SBI_CTL_DEST_ICLK | SBI_CTL_OP_CRWR;
+        else
+                tmp = SBI_CTL_DEST_MPHY | SBI_CTL_OP_IOWR;
+        I915_WRITE(SBI_CTL_STAT, SBI_BUSY | tmp);
 
         if (wait_for((I915_READ(SBI_CTL_STAT) & (SBI_BUSY | SBI_RESPONSE_FAIL)) == 0,
                                 100)) {
@@ -1536,23 +1538,25 @@ out_unlock:
 }
 
 static u32
-intel_sbi_read(struct drm_i915_private *dev_priv, u16 reg)
+intel_sbi_read(struct drm_i915_private *dev_priv, u16 reg,
+               enum intel_sbi_destination destination)
 {
         unsigned long flags;
         u32 value = 0;
 
         spin_lock_irqsave(&dev_priv->dpio_lock, flags);
-        if (wait_for((I915_READ(SBI_CTL_STAT) & SBI_BUSY) == 0,
-                                100)) {
+        if (wait_for((I915_READ(SBI_CTL_STAT) & SBI_BUSY) == 0, 100)) {
                 DRM_ERROR("timeout waiting for SBI to become ready\n");
                 goto out_unlock;
         }
 
-        I915_WRITE(SBI_ADDR,
-                        (reg << 16));
-        I915_WRITE(SBI_CTL_STAT,
-                        SBI_BUSY |
-                        SBI_CTL_OP_CRRD);
+        I915_WRITE(SBI_ADDR, (reg << 16));
+
+        if (destination == SBI_ICLK)
+                value = SBI_CTL_DEST_ICLK | SBI_CTL_OP_CRRD;
+        else
+                value = SBI_CTL_DEST_MPHY | SBI_CTL_OP_IORD;
+        I915_WRITE(SBI_CTL_STAT, value | SBI_BUSY);
 
         if (wait_for((I915_READ(SBI_CTL_STAT) & (SBI_BUSY | SBI_RESPONSE_FAIL)) == 0,
                                 100)) {
@@ -3024,8 +3028,9 @@ static void lpt_program_iclkip(struct drm_crtc *crtc)
 
         /* Disable SSCCTL */
         intel_sbi_write(dev_priv, SBI_SSCCTL6,
-                                intel_sbi_read(dev_priv, SBI_SSCCTL6) |
-                                        SBI_SSCCTL_DISABLE);
+                        intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK) |
+                                SBI_SSCCTL_DISABLE,
+                        SBI_ICLK);
 
         /* 20MHz is a corner case which is out of range for the 7-bit divisor */
         if (crtc->mode.clock == 20000) {
@@ -3066,33 +3071,25 @@ static void lpt_program_iclkip(struct drm_crtc *crtc)
                         phaseinc);
 
         /* Program SSCDIVINTPHASE6 */
-        temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6);
+        temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK);
         temp &= ~SBI_SSCDIVINTPHASE_DIVSEL_MASK;
         temp |= SBI_SSCDIVINTPHASE_DIVSEL(divsel);
         temp &= ~SBI_SSCDIVINTPHASE_INCVAL_MASK;
         temp |= SBI_SSCDIVINTPHASE_INCVAL(phaseinc);
         temp |= SBI_SSCDIVINTPHASE_DIR(phasedir);
         temp |= SBI_SSCDIVINTPHASE_PROPAGATE;
-
-        intel_sbi_write(dev_priv,
-                        SBI_SSCDIVINTPHASE6,
-                        temp);
+        intel_sbi_write(dev_priv, SBI_SSCDIVINTPHASE6, temp, SBI_ICLK);
 
         /* Program SSCAUXDIV */
-        temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6);
+        temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6, SBI_ICLK);
         temp &= ~SBI_SSCAUXDIV_FINALDIV2SEL(1);
         temp |= SBI_SSCAUXDIV_FINALDIV2SEL(auxdiv);
-        intel_sbi_write(dev_priv,
-                        SBI_SSCAUXDIV6,
-                        temp);
-
+        intel_sbi_write(dev_priv, SBI_SSCAUXDIV6, temp, SBI_ICLK);
 
         /* Enable modulator and associated divider */
-        temp = intel_sbi_read(dev_priv, SBI_SSCCTL6);
+        temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK);
         temp &= ~SBI_SSCCTL_DISABLE;
-        intel_sbi_write(dev_priv,
-                        SBI_SSCCTL6,
-                        temp);
+        intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK);
 
         /* Wait for initialization time */
         udelay(24);