drm/i915: remove confusing GPIO vs PCH_GPIO

Instead of defining all registers twice, define just a PCH_GPIO_BASE
that has the same address as PCH_GPIO_A and use that to calculate all
the others. This also brings VLV and !HAS_GMCH_DISPLAY in line, doing
the same thing.

v2: Fix GMBUS registers to be relative to gpio base; create GPIO()
    macro to return a particular gpio address and move the enum out of
    i915_reg.h (suggested by Jani)

v3: Move base offset inside the GPIO() macro so the GMBUS defines don't
    actually need to be changed (suggested by Daniel/Ville)

v4: Move definition of i915_gpio to intel_display.h and remove
    GMBUS/GPIO handling from gvt since now they have their own
    defines.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180727193647.8639-3-lucas.demarchi@intel.com

drivers/gpu/drm/i915/i915_drv.h

@@ -1643,7 +1643,8 @@ struct drm_i915_private {
 	struct mutex gmbus_mutex;
 
 	/**
-	 * Base address of the gmbus and gpio block.
+	 * Base address of where the gmbus and gpio blocks are located (either
+	 * on PCH or on SoC for platforms without PCH).
 	 */
 	uint32_t gpio_mmio_base;
 

drivers/gpu/drm/i915/i915_reg.h

@@ -3082,18 +3082,9 @@ enum i915_power_well_id {
 /*
  * GPIO regs
  */
-#define GPIOA			_MMIO(0x5010)
-#define GPIOB			_MMIO(0x5014)
-#define GPIOC			_MMIO(0x5018)
-#define GPIOD			_MMIO(0x501c)
-#define GPIOE			_MMIO(0x5020)
-#define GPIOF			_MMIO(0x5024)
-#define GPIOG			_MMIO(0x5028)
-#define GPIOH			_MMIO(0x502c)
-#define GPIOJ			_MMIO(0x5034)
-#define GPIOK			_MMIO(0x5038)
-#define GPIOL			_MMIO(0x503C)
-#define GPIOM			_MMIO(0x5040)
+#define GPIO(gpio)		_MMIO(dev_priv->gpio_mmio_base + 0x5010 + \
+				      4 * (gpio))
+
 # define GPIO_CLOCK_DIR_MASK		(1 << 0)
 # define GPIO_CLOCK_DIR_IN		(0 << 1)
 # define GPIO_CLOCK_DIR_OUT		(1 << 1)
@@ -7489,6 +7480,8 @@ enum {
 
 /* PCH */
 
+#define PCH_DISPLAY_BASE	0xc0000u
+
 /* south display engine interrupt: IBX */
 #define SDE_AUDIO_POWER_D	(1 << 27)
 #define SDE_AUDIO_POWER_C	(1 << 26)
@@ -7783,13 +7776,6 @@ enum {
 #define   ICP_TC_HPD_LONG_DETECT(tc_port)	(2 << (tc_port) * 4)
 #define   ICP_TC_HPD_SHORT_DETECT(tc_port)	(1 << (tc_port) * 4)
 
-#define PCH_GPIOA               _MMIO(0xc5010)
-#define PCH_GPIOB               _MMIO(0xc5014)
-#define PCH_GPIOC               _MMIO(0xc5018)
-#define PCH_GPIOD               _MMIO(0xc501c)
-#define PCH_GPIOE               _MMIO(0xc5020)
-#define PCH_GPIOF               _MMIO(0xc5024)
-
 #define _PCH_DPLL_A              0xc6014
 #define _PCH_DPLL_B              0xc6018
 #define PCH_DPLL(pll) _MMIO((pll) == 0 ? _PCH_DPLL_A : _PCH_DPLL_B)

drivers/gpu/drm/i915/intel_display.h

@@ -25,6 +25,22 @@
 #ifndef _INTEL_DISPLAY_H_
 #define _INTEL_DISPLAY_H_
 
+enum i915_gpio {
+	GPIOA,
+	GPIOB,
+	GPIOC,
+	GPIOD,
+	GPIOE,
+	GPIOF,
+	GPIOG,
+	GPIOH,
+	__GPIOI_UNUSED,
+	GPIOJ,
+	GPIOK,
+	GPIOL,
+	GPIOM,
+};
+
 enum pipe {
 	INVALID_PIPE = -1,
 

drivers/gpu/drm/i915/intel_i2c.c

@@ -37,7 +37,7 @@
 
 struct gmbus_pin {
 	const char *name;
-	i915_reg_t reg;
+	enum i915_gpio gpio;
 };
 
 /* Map gmbus pin pairs to names and registers. */
@@ -121,8 +121,7 @@ bool intel_gmbus_is_valid_pin(struct drm_i915_private *dev_priv,
 	else
 		size = ARRAY_SIZE(gmbus_pins);
 
-	return pin < size &&
-		i915_mmio_reg_valid(get_gmbus_pin(dev_priv, pin)->reg);
+	return pin < size && get_gmbus_pin(dev_priv, pin)->name;
 }
 
 /* Intel GPIO access functions */
@@ -292,8 +291,7 @@ intel_gpio_setup(struct intel_gmbus *bus, unsigned int pin)
 
 	algo = &bus->bit_algo;
 
-	bus->gpio_reg = _MMIO(dev_priv->gpio_mmio_base +
-			      i915_mmio_reg_offset(get_gmbus_pin(dev_priv, pin)->reg));
+	bus->gpio_reg = GPIO(get_gmbus_pin(dev_priv, pin)->gpio);
 	bus->adapter.algo_data = algo;
 	algo->setsda = set_data;
 	algo->setscl = set_clock;
@@ -825,9 +823,11 @@ int intel_setup_gmbus(struct drm_i915_private *dev_priv)
 	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
 		dev_priv->gpio_mmio_base = VLV_DISPLAY_BASE;
 	else if (!HAS_GMCH_DISPLAY(dev_priv))
-		dev_priv->gpio_mmio_base =
-			i915_mmio_reg_offset(PCH_GPIOA) -
-			i915_mmio_reg_offset(GPIOA);
+		/*
+		 * Broxton uses the same PCH offsets for South Display Engine,
+		 * even though it doesn't have a PCH.
+		 */
+		dev_priv->gpio_mmio_base = PCH_DISPLAY_BASE;
 
 	mutex_init(&dev_priv->gmbus_mutex);
 	init_waitqueue_head(&dev_priv->gmbus_wait_queue);