drm: sti: add cursor plane

stih407 SoC have a dedicated hardware cursor plane,
this patch enable it.
The hardware have a color look up table, fix it to
be able to use ARGB8888.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

1 files changed, 242 insertions, 0 deletions

diff --git a/drivers/gpu/drm/sti/sti_cursor.c b/drivers/gpu/drm/sti/sti_cursor.c
new file mode 100644
index 000000000000..010eaee60bf7
--- /dev/null
+++ b/drivers/gpu/drm/sti/sti_cursor.c
@@ -0,0 +1,242 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Authors: Vincent Abriou <vincent.abriou@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+#include <drm/drmP.h>
+
+#include "sti_cursor.h"
+#include "sti_layer.h"
+#include "sti_vtg.h"
+
+/* Registers */
+#define CUR_CTL             0x00
+#define CUR_VPO             0x0C
+#define CUR_PML             0x14
+#define CUR_PMP             0x18
+#define CUR_SIZE            0x1C
+#define CUR_CML             0x20
+#define CUR_AWS             0x28
+#define CUR_AWE             0x2C
+
+#define CUR_CTL_CLUT_UPDATE BIT(1)
+
+#define STI_CURS_MIN_SIZE   1
+#define STI_CURS_MAX_SIZE   128
+
+/*
+ * pixmap dma buffer stucture
+ *
+ * @paddr:  physical address
+ * @size:   buffer size
+ * @base:   virtual address
+ */
+struct dma_pixmap {
+	dma_addr_t paddr;
+	size_t size;
+	void *base;
+};
+
+/**
+ * STI Cursor structure
+ *
+ * @layer:      layer structure
+ * @width:      cursor width
+ * @height:     cursor height
+ * @clut:       color look up table
+ * @clut_paddr: color look up table physical address
+ * @pixmap:     pixmap dma buffer (clut8-format cursor)
+ */
+struct sti_cursor {
+	struct sti_layer layer;
+	unsigned int width;
+	unsigned int height;
+	unsigned short *clut;
+	dma_addr_t clut_paddr;
+	struct dma_pixmap pixmap;
+};
+
+static const uint32_t cursor_supported_formats[] = {
+	DRM_FORMAT_ARGB8888,
+};
+
+#define to_sti_cursor(x) container_of(x, struct sti_cursor, layer)
+
+static const uint32_t *sti_cursor_get_formats(struct sti_layer *layer)
+{
+	return cursor_supported_formats;
+}
+
+static unsigned int sti_cursor_get_nb_formats(struct sti_layer *layer)
+{
+	return ARRAY_SIZE(cursor_supported_formats);
+}
+
+static void sti_cursor_argb8888_to_clut8(struct sti_layer *layer)
+{
+	struct sti_cursor *cursor = to_sti_cursor(layer);
+	u32 *src = layer->vaddr;
+	u8  *dst = cursor->pixmap.base;
+	unsigned int i, j;
+	u32 a, r, g, b;
+
+	for (i = 0; i < cursor->height; i++) {
+		for (j = 0; j < cursor->width; j++) {
+			/* Pick the 2 higher bits of each component */
+			a = (*src >> 30) & 3;
+			r = (*src >> 22) & 3;
+			g = (*src >> 14) & 3;
+			b = (*src >> 6) & 3;
+			*dst = a << 6 | r << 4 | g << 2 | b;
+			src++;
+			dst++;
+		}
+	}
+}
+
+static int sti_cursor_prepare_layer(struct sti_layer *layer, bool first_prepare)
+{
+	struct sti_cursor *cursor = to_sti_cursor(layer);
+	struct drm_display_mode *mode = layer->mode;
+	u32 y, x;
+	u32 val;
+
+	DRM_DEBUG_DRIVER("\n");
+
+	dev_dbg(layer->dev, "%s %s\n", __func__, sti_layer_to_str(layer));
+
+	if (layer->src_w < STI_CURS_MIN_SIZE ||
+	    layer->src_h < STI_CURS_MIN_SIZE ||
+	    layer->src_w > STI_CURS_MAX_SIZE ||
+	    layer->src_h > STI_CURS_MAX_SIZE) {
+		DRM_ERROR("Invalid cursor size (%dx%d)\n",
+				layer->src_w, layer->src_h);
+		return -EINVAL;
+	}
+
+	/* If the cursor size has changed, re-allocated the pixmap */
+	if (!cursor->pixmap.base ||
+	    (cursor->width != layer->src_w) ||
+	    (cursor->height != layer->src_h)) {
+		cursor->width = layer->src_w;
+		cursor->height = layer->src_h;
+
+		if (cursor->pixmap.base)
+			dma_free_writecombine(layer->dev,
+					      cursor->pixmap.size,
+					      cursor->pixmap.base,
+					      cursor->pixmap.paddr);
+
+		cursor->pixmap.size = cursor->width * cursor->height;
+
+		cursor->pixmap.base = dma_alloc_writecombine(layer->dev,
+							cursor->pixmap.size,
+							&cursor->pixmap.paddr,
+							GFP_KERNEL | GFP_DMA);
+		if (!cursor->pixmap.base) {
+			DRM_ERROR("Failed to allocate memory for pixmap\n");
+			return -ENOMEM;
+		}
+	}
+
+	/* Convert ARGB8888 to CLUT8 */
+	sti_cursor_argb8888_to_clut8(layer);
+
+	/* AWS and AWE depend on the mode */
+	y = sti_vtg_get_line_number(*mode, 0);
+	x = sti_vtg_get_pixel_number(*mode, 0);
+	val = y << 16 | x;
+	writel(val, layer->regs + CUR_AWS);
+	y = sti_vtg_get_line_number(*mode, mode->vdisplay - 1);
+	x = sti_vtg_get_pixel_number(*mode, mode->hdisplay - 1);
+	val = y << 16 | x;
+	writel(val, layer->regs + CUR_AWE);
+
+	if (first_prepare) {
+		/* Set and fetch CLUT */
+		writel(cursor->clut_paddr, layer->regs + CUR_CML);
+		writel(CUR_CTL_CLUT_UPDATE, layer->regs + CUR_CTL);
+	}
+
+	return 0;
+}
+
+static int sti_cursor_commit_layer(struct sti_layer *layer)
+{
+	struct sti_cursor *cursor = to_sti_cursor(layer);
+	struct drm_display_mode *mode = layer->mode;
+	u32 ydo, xdo;
+
+	dev_dbg(layer->dev, "%s %s\n", __func__, sti_layer_to_str(layer));
+
+	/* Set memory location, size, and position */
+	writel(cursor->pixmap.paddr, layer->regs + CUR_PML);
+	writel(cursor->width, layer->regs + CUR_PMP);
+	writel(cursor->height << 16 | cursor->width, layer->regs + CUR_SIZE);
+
+	ydo = sti_vtg_get_line_number(*mode, layer->dst_y);
+	xdo = sti_vtg_get_pixel_number(*mode, layer->dst_y);
+	writel((ydo << 16) | xdo, layer->regs + CUR_VPO);
+
+	return 0;
+}
+
+static int sti_cursor_disable_layer(struct sti_layer *layer)
+{
+	return 0;
+}
+
+static void sti_cursor_init(struct sti_layer *layer)
+{
+	struct sti_cursor *cursor = to_sti_cursor(layer);
+	unsigned short *base = cursor->clut;
+	unsigned int a, r, g, b;
+
+	/* Assign CLUT values, ARGB444 format */
+	for (a = 0; a < 4; a++)
+		for (r = 0; r < 4; r++)
+			for (g = 0; g < 4; g++)
+				for (b = 0; b < 4; b++)
+					*base++ = (a * 5) << 12 |
+						  (r * 5) << 8 |
+						  (g * 5) << 4 |
+						  (b * 5);
+}
+
+static const struct sti_layer_funcs cursor_ops = {
+	.get_formats = sti_cursor_get_formats,
+	.get_nb_formats = sti_cursor_get_nb_formats,
+	.init = sti_cursor_init,
+	.prepare = sti_cursor_prepare_layer,
+	.commit = sti_cursor_commit_layer,
+	.disable = sti_cursor_disable_layer,
+};
+
+struct sti_layer *sti_cursor_create(struct device *dev)
+{
+	struct sti_cursor *cursor;
+
+	cursor = devm_kzalloc(dev, sizeof(*cursor), GFP_KERNEL);
+	if (!cursor) {
+		DRM_ERROR("Failed to allocate memory for cursor\n");
+		return NULL;
+	}
+
+	/* Allocate clut buffer */
+	cursor->clut = dma_alloc_writecombine(dev,
+			0x100 * sizeof(unsigned short),
+			&cursor->clut_paddr,
+			GFP_KERNEL | GFP_DMA);
+
+	if (!cursor->clut) {
+		DRM_ERROR("Failed to allocate memory for cursor clut\n");
+		devm_kfree(dev, cursor);
+		return NULL;
+	}
+
+	cursor->layer.ops = &cursor_ops;
+
+	return (struct sti_layer *)cursor;
+}