DRM: Armada: Add Armada DRM driver

This patch adds support for the pair of LCD controllers on the Marvell
Armada 510 SoCs.  This driver supports:
- multiple contiguous scanout buffers for video and graphics
- shm backed cacheable buffer objects for X pixmaps for Vivante GPU
  acceleration
- dual lcd0 and lcd1 crt operation
- video overlay on each LCD crt via DRM planes
- page flipping of the main scanout buffers
- DRM prime for buffer export/import

This driver is trivial to extend to other Armada SoCs.

Included in this commit is the core driver with no output support; output
support is platform and encoder driver dependent.

Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 183 insertions, 0 deletions

diff --git a/drivers/gpu/drm/armada/armada_debugfs.c b/drivers/gpu/drm/armada/armada_debugfs.c
new file mode 100644
index 000000000000..612f3753cd92
--- /dev/null
+++ b/drivers/gpu/drm/armada/armada_debugfs.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (C) 2012 Russell King
+ *  Rewritten from the dovefb driver, and Armada510 manuals.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <drm/drmP.h>
+#include "armada_crtc.h"
+#include "armada_drm.h"
+
+static int armada_debugfs_gem_linear_show(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct armada_private *priv = dev->dev_private;
+	int ret;
+
+	mutex_lock(&dev->struct_mutex);
+	ret = drm_mm_dump_table(m, &priv->linear);
+	mutex_unlock(&dev->struct_mutex);
+
+	return ret;
+}
+
+static int armada_debugfs_reg_show(struct seq_file *m, void *data)
+{
+	struct drm_device *dev = m->private;
+	struct armada_private *priv = dev->dev_private;
+	int n, i;
+
+	if (priv) {
+		for (n = 0; n < ARRAY_SIZE(priv->dcrtc); n++) {
+			struct armada_crtc *dcrtc = priv->dcrtc[n];
+			if (!dcrtc)
+				continue;
+
+			for (i = 0x84; i <= 0x1c4; i += 4) {
+				uint32_t v = readl_relaxed(dcrtc->base + i);
+				seq_printf(m, "%u: 0x%04x: 0x%08x\n", n, i, v);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int armada_debugfs_reg_r_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, armada_debugfs_reg_show, inode->i_private);
+}
+
+static const struct file_operations fops_reg_r = {
+	.owner = THIS_MODULE,
+	.open = armada_debugfs_reg_r_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static int armada_debugfs_write(struct file *file, const char __user *ptr,
+	size_t len, loff_t *off)
+{
+	struct drm_device *dev = file->private_data;
+	struct armada_private *priv = dev->dev_private;
+	struct armada_crtc *dcrtc = priv->dcrtc[0];
+	char buf[32], *p;
+	uint32_t reg, val;
+	int ret;
+
+	if (*off != 0)
+		return 0;
+
+	if (len > sizeof(buf) - 1)
+		len = sizeof(buf) - 1;
+
+	ret = strncpy_from_user(buf, ptr, len);
+	if (ret < 0)
+		return ret;
+	buf[len] = '\0';
+
+	reg = simple_strtoul(buf, &p, 16);
+	if (!isspace(*p))
+		return -EINVAL;
+	val = simple_strtoul(p + 1, NULL, 16);
+
+	if (reg >= 0x84 && reg <= 0x1c4)
+		writel(val, dcrtc->base + reg);
+
+	return len;
+}
+
+static int armada_debugfs_reg_w_open(struct inode *inode, struct file *file)
+{
+	file->private_data = inode->i_private;
+	return 0;
+}
+
+static const struct file_operations fops_reg_w = {
+	.owner = THIS_MODULE,
+	.open = armada_debugfs_reg_w_open,
+	.write = armada_debugfs_write,
+	.llseek = noop_llseek,
+};
+
+static struct drm_info_list armada_debugfs_list[] = {
+	{ "gem_linear", armada_debugfs_gem_linear_show, 0 },
+};
+#define ARMADA_DEBUGFS_ENTRIES ARRAY_SIZE(armada_debugfs_list)
+
+static int drm_add_fake_info_node(struct drm_minor *minor, struct dentry *ent,
+	const void *key)
+{
+	struct drm_info_node *node;
+
+	node = kmalloc(sizeof(struct drm_info_node), GFP_KERNEL);
+	if (node == NULL) {
+		debugfs_remove(ent);
+		return -ENOMEM;
+	}
+
+	node->minor = minor;
+	node->dent = ent;
+	node->info_ent = (void *) key;
+
+	mutex_lock(&minor->debugfs_lock);
+	list_add(&node->list, &minor->debugfs_list);
+	mutex_unlock(&minor->debugfs_lock);
+
+	return 0;
+}
+
+static int armada_debugfs_create(struct dentry *root, struct drm_minor *minor,
+	const char *name, umode_t mode, const struct file_operations *fops)
+{
+	struct dentry *de;
+
+	de = debugfs_create_file(name, mode, root, minor->dev, fops);
+
+	return drm_add_fake_info_node(minor, de, fops);
+}
+
+int armada_drm_debugfs_init(struct drm_minor *minor)
+{
+	int ret;
+
+	ret = drm_debugfs_create_files(armada_debugfs_list,
+				       ARMADA_DEBUGFS_ENTRIES,
+				       minor->debugfs_root, minor);
+	if (ret)
+		return ret;
+
+	ret = armada_debugfs_create(minor->debugfs_root, minor,
+				   "reg", S_IFREG | S_IRUSR, &fops_reg_r);
+	if (ret)
+		goto err_1;
+
+	ret = armada_debugfs_create(minor->debugfs_root, minor,
+				"reg_wr", S_IFREG | S_IWUSR, &fops_reg_w);
+	if (ret)
+		goto err_2;
+	return ret;
+
+ err_2:
+	drm_debugfs_remove_files((struct drm_info_list *)&fops_reg_r, 1, minor);
+ err_1:
+	drm_debugfs_remove_files(armada_debugfs_list, ARMADA_DEBUGFS_ENTRIES,
+				 minor);
+	return ret;
+}
+
+void armada_drm_debugfs_cleanup(struct drm_minor *minor)
+{
+	drm_debugfs_remove_files((struct drm_info_list *)&fops_reg_w, 1, minor);
+	drm_debugfs_remove_files((struct drm_info_list *)&fops_reg_r, 1, minor);
+	drm_debugfs_remove_files(armada_debugfs_list, ARMADA_DEBUGFS_ENTRIES,
+				 minor);
+}