drm/pl111: Enable PL110 variant

We detect and enable the use of the PL110 variant, an earlier
incarnation of PL111. The only real difference is that the
control and interrupt enable registers have swapped place.
The Versatile AB and Versatile PB have a variant inbetween
PL110 and PL111, it is PL110 but they have already swapped the
two registers so those two need a bit of special handling.

Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20170908124709.4758-4-linus.walleij@linaro.org

1 files changed, 83 insertions, 3 deletions

diff --git a/drivers/gpu/drm/pl111/pl111_drv.c b/drivers/gpu/drm/pl111/pl111_drv.c
index 7dae687a8df4..7a47db066a78 100644
--- a/drivers/gpu/drm/pl111/pl111_drv.c
+++ b/drivers/gpu/drm/pl111/pl111_drv.c
@@ -200,6 +200,7 @@ static int pl111_amba_probe(struct amba_device *amba_dev,
 {
 	struct device *dev = &amba_dev->dev;
 	struct pl111_drm_dev_private *priv;
+	struct pl111_variant_data *variant = id->data;
 	struct drm_device *drm;
 	int ret;
 
@@ -213,6 +214,33 @@ static int pl111_amba_probe(struct amba_device *amba_dev,
 	amba_set_drvdata(amba_dev, drm);
 	priv->drm = drm;
 	drm->dev_private = priv;
+	priv->variant = variant;
+
+	/*
+	 * The PL110 and PL111 variants have two registers
+	 * swapped: interrupt enable and control. For this reason
+	 * we use offsets that we can change per variant.
+	 */
+	if (variant->is_pl110) {
+		/*
+		 * The ARM Versatile boards are even more special:
+		 * their PrimeCell ID say they are PL110 but the
+		 * control and interrupt enable registers are anyway
+		 * swapped to the PL111 order so they are not following
+		 * the PL110 datasheet.
+		 */
+		if (of_machine_is_compatible("arm,versatile-ab") ||
+		    of_machine_is_compatible("arm,versatile-pb")) {
+			priv->ienb = CLCD_PL111_IENB;
+			priv->ctrl = CLCD_PL111_CNTL;
+		} else {
+			priv->ienb = CLCD_PL110_IENB;
+			priv->ctrl = CLCD_PL110_CNTL;
+		}
+	} else {
+		priv->ienb = CLCD_PL111_IENB;
+		priv->ctrl = CLCD_PL111_CNTL;
+	}
 
 	priv->regs = devm_ioremap_resource(dev, &amba_dev->res);
 	if (IS_ERR(priv->regs)) {
@@ -221,10 +249,10 @@ static int pl111_amba_probe(struct amba_device *amba_dev,
 	}
 
 	/* turn off interrupts before requesting the irq */
-	writel(0, priv->regs + CLCD_PL111_IENB);
+	writel(0, priv->regs + priv->ienb);
 
 	ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0,
-			       "pl111", priv);
+			       variant->name, priv);
 	if (ret != 0) {
 		dev_err(dev, "%s failed irq %d\n", __func__, ret);
 		return ret;
@@ -261,10 +289,62 @@ static int pl111_amba_remove(struct amba_device *amba_dev)
 	return 0;
 }
 
-static struct amba_id pl111_id_table[] = {
+/*
+ * This variant exist in early versions like the ARM Integrator
+ * and this version lacks the 565 and 444 pixel formats.
+ */
+static const u32 pl110_pixel_formats[] = {
+	DRM_FORMAT_ABGR8888,
+	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_ABGR1555,
+	DRM_FORMAT_XBGR1555,
+	DRM_FORMAT_ARGB1555,
+	DRM_FORMAT_XRGB1555,
+};
+
+static const struct pl111_variant_data pl110_variant = {
+	.name = "PL110",
+	.is_pl110 = true,
+	.formats = pl110_pixel_formats,
+	.nformats = ARRAY_SIZE(pl110_pixel_formats),
+};
+
+/* RealView, Versatile Express etc use this modern variant */
+static const u32 pl111_pixel_formats[] = {
+	DRM_FORMAT_ABGR8888,
+	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_BGR565,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_ABGR1555,
+	DRM_FORMAT_XBGR1555,
+	DRM_FORMAT_ARGB1555,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_ABGR4444,
+	DRM_FORMAT_XBGR4444,
+	DRM_FORMAT_ARGB4444,
+	DRM_FORMAT_XRGB4444,
+};
+
+static const struct pl111_variant_data pl111_variant = {
+	.name = "PL111",
+	.formats = pl111_pixel_formats,
+	.nformats = ARRAY_SIZE(pl111_pixel_formats),
+};
+
+static const struct amba_id pl111_id_table[] = {
+	{
+		.id = 0x00041110,
+		.mask = 0x000fffff,
+		.data = (void*)&pl110_variant,
+	},
 	{
 		.id = 0x00041111,
 		.mask = 0x000fffff,
+		.data = (void*)&pl111_variant,
 	},
 	{0, 0},
 };