summary refs log tree commit diff
path: root/drivers/video/fbdev/vermilion/cr_pll.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/video/fbdev/vermilion/cr_pll.c')
-rw-r--r--drivers/video/fbdev/vermilion/cr_pll.c208
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/video/fbdev/vermilion/cr_pll.c b/drivers/video/fbdev/vermilion/cr_pll.c
new file mode 100644
index 000000000000..ebc6e6e0dd0f
--- /dev/null
+++ b/drivers/video/fbdev/vermilion/cr_pll.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) Intel Corp. 2007.
+ * All Rights Reserved.
+ *
+ * Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
+ * develop this driver.
+ *
+ * This file is part of the Carillo Ranch video subsystem driver.
+ * The Carillo Ranch video subsystem driver is free software;
+ * you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * The Carillo Ranch video subsystem driver is distributed
+ * in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this driver; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Authors:
+ *   Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
+ *   Alan Hourihane <alanh-at-tungstengraphics-dot-com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include "vermilion.h"
+
+/* The PLL Clock register sits on Host bridge */
+#define CRVML_DEVICE_MCH   0x5001
+#define CRVML_REG_MCHBAR   0x44
+#define CRVML_REG_MCHEN    0x54
+#define CRVML_MCHEN_BIT    (1 << 28)
+#define CRVML_MCHMAP_SIZE  4096
+#define CRVML_REG_CLOCK    0xc3c
+#define CRVML_CLOCK_SHIFT  8
+#define CRVML_CLOCK_MASK   0x00000f00
+
+static struct pci_dev *mch_dev;
+static u32 mch_bar;
+static void __iomem *mch_regs_base;
+static u32 saved_clock;
+
+static const unsigned crvml_clocks[] = {
+	6750,
+	13500,
+	27000,
+	29700,
+	37125,
+	54000,
+	59400,
+	74250,
+	120000
+	    /*
+	     * There are more clocks, but they are disabled on the CR board.
+	     */
+};
+
+static const u32 crvml_clock_bits[] = {
+	0x0a,
+	0x09,
+	0x08,
+	0x07,
+	0x06,
+	0x05,
+	0x04,
+	0x03,
+	0x0b
+};
+
+static const unsigned crvml_num_clocks = ARRAY_SIZE(crvml_clocks);
+
+static int crvml_sys_restore(struct vml_sys *sys)
+{
+	void __iomem *clock_reg = mch_regs_base + CRVML_REG_CLOCK;
+
+	iowrite32(saved_clock, clock_reg);
+	ioread32(clock_reg);
+
+	return 0;
+}
+
+static int crvml_sys_save(struct vml_sys *sys)
+{
+	void __iomem *clock_reg = mch_regs_base + CRVML_REG_CLOCK;
+
+	saved_clock = ioread32(clock_reg);
+
+	return 0;
+}
+
+static int crvml_nearest_index(const struct vml_sys *sys, int clock)
+{
+	int i;
+	int cur_index = 0;
+	int cur_diff;
+	int diff;
+
+	cur_diff = clock - crvml_clocks[0];
+	cur_diff = (cur_diff < 0) ? -cur_diff : cur_diff;
+	for (i = 1; i < crvml_num_clocks; ++i) {
+		diff = clock - crvml_clocks[i];
+		diff = (diff < 0) ? -diff : diff;
+		if (diff < cur_diff) {
+			cur_index = i;
+			cur_diff = diff;
+		}
+	}
+	return cur_index;
+}
+
+static int crvml_nearest_clock(const struct vml_sys *sys, int clock)
+{
+	return crvml_clocks[crvml_nearest_index(sys, clock)];
+}
+
+static int crvml_set_clock(struct vml_sys *sys, int clock)
+{
+	void __iomem *clock_reg = mch_regs_base + CRVML_REG_CLOCK;
+	int index;
+	u32 clock_val;
+
+	index = crvml_nearest_index(sys, clock);
+
+	if (crvml_clocks[index] != clock)
+		return -EINVAL;
+
+	clock_val = ioread32(clock_reg) & ~CRVML_CLOCK_MASK;
+	clock_val = crvml_clock_bits[index] << CRVML_CLOCK_SHIFT;
+	iowrite32(clock_val, clock_reg);
+	ioread32(clock_reg);
+
+	return 0;
+}
+
+static struct vml_sys cr_pll_ops = {
+	.name = "Carillo Ranch",
+	.save = crvml_sys_save,
+	.restore = crvml_sys_restore,
+	.set_clock = crvml_set_clock,
+	.nearest_clock = crvml_nearest_clock,
+};
+
+static int __init cr_pll_init(void)
+{
+	int err;
+	u32 dev_en;
+
+	mch_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
+					CRVML_DEVICE_MCH, NULL);
+	if (!mch_dev) {
+		printk(KERN_ERR
+		       "Could not find Carillo Ranch MCH device.\n");
+		return -ENODEV;
+	}
+
+	pci_read_config_dword(mch_dev, CRVML_REG_MCHEN, &dev_en);
+	if (!(dev_en & CRVML_MCHEN_BIT)) {
+		printk(KERN_ERR
+		       "Carillo Ranch MCH device was not enabled.\n");
+		pci_dev_put(mch_dev);
+		return -ENODEV;
+	}
+
+	pci_read_config_dword(mch_dev, CRVML_REG_MCHBAR,
+			      &mch_bar);
+	mch_regs_base =
+	    ioremap_nocache(mch_bar, CRVML_MCHMAP_SIZE);
+	if (!mch_regs_base) {
+		printk(KERN_ERR
+		       "Carillo Ranch MCH device was not enabled.\n");
+		pci_dev_put(mch_dev);
+		return -ENODEV;
+	}
+
+	err = vmlfb_register_subsys(&cr_pll_ops);
+	if (err) {
+		printk(KERN_ERR
+		       "Carillo Ranch failed to initialize vml_sys.\n");
+		pci_dev_put(mch_dev);
+		return err;
+	}
+
+	return 0;
+}
+
+static void __exit cr_pll_exit(void)
+{
+	vmlfb_unregister_subsys(&cr_pll_ops);
+
+	iounmap(mch_regs_base);
+	pci_dev_put(mch_dev);
+}
+
+module_init(cr_pll_init);
+module_exit(cr_pll_exit);
+
+MODULE_AUTHOR("Tungsten Graphics Inc.");
+MODULE_DESCRIPTION("Carillo Ranch PLL Driver");
+MODULE_LICENSE("GPL");