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path: root/drivers/video/fbdev/vermilion/cr_pll.c
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Diffstat (limited to 'drivers/video/fbdev/vermilion/cr_pll.c')
-rw-r--r--drivers/video/fbdev/vermilion/cr_pll.c195
1 files changed, 195 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 000000000..79d42b23d
--- /dev/null
+++ b/drivers/video/fbdev/vermilion/cr_pll.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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.
+ *
+ * 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(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");
+ iounmap(mch_regs_base);
+ 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");