/*
* 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");
