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-rw-r--r--drivers/clocksource/Makefile2
-rw-r--r--drivers/clocksource/acpi_pm.c177
-rw-r--r--drivers/clocksource/cyclone.c119
3 files changed, 298 insertions, 0 deletions
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
new file mode 100644
index 0000000..be3511a
--- /dev/null
+++ b/drivers/clocksource/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_X86_CYCLONE_TIMER) += cyclone.o
+obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o
diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
new file mode 100644
index 0000000..a0e5cde
--- /dev/null
+++ b/drivers/clocksource/acpi_pm.c
@@ -0,0 +1,177 @@
+/*
+ * linux/drivers/clocksource/acpi_pm.c
+ *
+ * This file contains the ACPI PM based clocksource.
+ *
+ * This code was largely moved from the i386 timer_pm.c file
+ * which was (C) Dominik Brodowski <linux@brodo.de> 2003
+ * and contained the following comments:
+ *
+ * Driver to use the Power Management Timer (PMTMR) available in some
+ * southbridges as primary timing source for the Linux kernel.
+ *
+ * Based on parts of linux/drivers/acpi/hardware/hwtimer.c, timer_pit.c,
+ * timer_hpet.c, and on Arjan van de Ven's implementation for 2.4.
+ *
+ * This file is licensed under the GPL v2.
+ */
+
+#include <linux/clocksource.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <asm/io.h>
+
+/* Number of PMTMR ticks expected during calibration run */
+#define PMTMR_TICKS_PER_SEC 3579545
+
+/*
+ * The I/O port the PMTMR resides at.
+ * The location is detected during setup_arch(),
+ * in arch/i386/acpi/boot.c
+ */
+u32 pmtmr_ioport;
+
+#define ACPI_PM_MASK 0xFFFFFF /* limit it to 24 bits */
+
+static inline u32 read_pmtmr(void)
+{
+ /* mask the output to 24 bits */
+ return inl(pmtmr_ioport) & ACPI_PM_MASK;
+}
+
+static cycle_t acpi_pm_read_verified(void)
+{
+ u32 v1 = 0, v2 = 0, v3 = 0;
+
+ /*
+ * It has been reported that because of various broken
+ * chipsets (ICH4, PIIX4 and PIIX4E) where the ACPI PM clock
+ * source is not latched, so you must read it multiple
+ * times to ensure a safe value is read:
+ */
+ do {
+ v1 = read_pmtmr();
+ v2 = read_pmtmr();
+ v3 = read_pmtmr();
+ } while ((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
+ || (v3 > v1 && v3 < v2));
+
+ return (cycle_t)v2;
+}
+
+static cycle_t acpi_pm_read(void)
+{
+ return (cycle_t)read_pmtmr();
+}
+
+static struct clocksource clocksource_acpi_pm = {
+ .name = "acpi_pm",
+ .rating = 200,
+ .read = acpi_pm_read,
+ .mask = (cycle_t)ACPI_PM_MASK,
+ .mult = 0, /*to be caluclated*/
+ .shift = 22,
+ .is_continuous = 1,
+};
+
+
+#ifdef CONFIG_PCI
+static int acpi_pm_good;
+static int __init acpi_pm_good_setup(char *__str)
+{
+ acpi_pm_good = 1;
+ return 1;
+}
+__setup("acpi_pm_good", acpi_pm_good_setup);
+
+static inline void acpi_pm_need_workaround(void)
+{
+ clocksource_acpi_pm.read = acpi_pm_read_verified;
+ clocksource_acpi_pm.rating = 110;
+}
+
+/*
+ * PIIX4 Errata:
+ *
+ * The power management timer may return improper results when read.
+ * Although the timer value settles properly after incrementing,
+ * while incrementing there is a 3 ns window every 69.8 ns where the
+ * timer value is indeterminate (a 4.2% chance that the data will be
+ * incorrect when read). As a result, the ACPI free running count up
+ * timer specification is violated due to erroneous reads.
+ */
+static void __devinit acpi_pm_check_blacklist(struct pci_dev *dev)
+{
+ u8 rev;
+
+ if (acpi_pm_good)
+ return;
+
+ pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
+ /* the bug has been fixed in PIIX4M */
+ if (rev < 3) {
+ printk(KERN_WARNING "* Found PM-Timer Bug on the chipset."
+ " Due to workarounds for a bug,\n"
+ "* this clock source is slow. Consider trying"
+ " other clock sources\n");
+
+ acpi_pm_need_workaround();
+ }
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3,
+ acpi_pm_check_blacklist);
+
+static void __devinit acpi_pm_check_graylist(struct pci_dev *dev)
+{
+ if (acpi_pm_good)
+ return;
+
+ printk(KERN_WARNING "* The chipset may have PM-Timer Bug. Due to"
+ " workarounds for a bug,\n"
+ "* this clock source is slow. If you are sure your timer"
+ " does not have\n"
+ "* this bug, please use \"acpi_pm_good\" to disable the"
+ " workaround\n");
+
+ acpi_pm_need_workaround();
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
+ acpi_pm_check_graylist);
+#endif
+
+
+static int __init init_acpi_pm_clocksource(void)
+{
+ u32 value1, value2;
+ unsigned int i;
+
+ if (!pmtmr_ioport)
+ return -ENODEV;
+
+ clocksource_acpi_pm.mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC,
+ clocksource_acpi_pm.shift);
+
+ /* "verify" this timing source: */
+ value1 = read_pmtmr();
+ for (i = 0; i < 10000; i++) {
+ value2 = read_pmtmr();
+ if (value2 == value1)
+ continue;
+ if (value2 > value1)
+ goto pm_good;
+ if ((value2 < value1) && ((value2) < 0xFFF))
+ goto pm_good;
+ printk(KERN_INFO "PM-Timer had inconsistent results:"
+ " 0x%#x, 0x%#x - aborting.\n", value1, value2);
+ return -EINVAL;
+ }
+ printk(KERN_INFO "PM-Timer had no reasonable result:"
+ " 0x%#x - aborting.\n", value1);
+ return -ENODEV;
+
+pm_good:
+ return register_clocksource(&clocksource_acpi_pm);
+}
+
+module_init(init_acpi_pm_clocksource);
diff --git a/drivers/clocksource/cyclone.c b/drivers/clocksource/cyclone.c
new file mode 100644
index 0000000..444eb11
--- /dev/null
+++ b/drivers/clocksource/cyclone.c
@@ -0,0 +1,119 @@
+#include <linux/clocksource.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/timex.h>
+#include <linux/init.h>
+
+#include <asm/pgtable.h>
+#include <asm/io.h>
+
+#include "mach_timer.h"
+
+#define CYCLONE_CBAR_ADDR 0xFEB00CD0 /* base address ptr */
+#define CYCLONE_PMCC_OFFSET 0x51A0 /* offset to control register */
+#define CYCLONE_MPCS_OFFSET 0x51A8 /* offset to select register */
+#define CYCLONE_MPMC_OFFSET 0x51D0 /* offset to count register */
+#define CYCLONE_TIMER_FREQ 99780000 /* 100Mhz, but not really */
+#define CYCLONE_TIMER_MASK 0xFFFFFFFF /* 32 bit mask */
+
+int use_cyclone = 0;
+static void __iomem *cyclone_ptr;
+
+static cycle_t read_cyclone(void)
+{
+ return (cycle_t)readl(cyclone_ptr);
+}
+
+static struct clocksource clocksource_cyclone = {
+ .name = "cyclone",
+ .rating = 250,
+ .read = read_cyclone,
+ .mask = (cycle_t)CYCLONE_TIMER_MASK,
+ .mult = 10,
+ .shift = 0,
+ .is_continuous = 1,
+};
+
+static int __init init_cyclone_clocksource(void)
+{
+ unsigned long base; /* saved value from CBAR */
+ unsigned long offset;
+ u32 __iomem* volatile cyclone_timer; /* Cyclone MPMC0 register */
+ u32 __iomem* reg;
+ int i;
+
+ /* make sure we're on a summit box: */
+ if (!use_cyclone)
+ return -ENODEV;
+
+ printk(KERN_INFO "Summit chipset: Starting Cyclone Counter.\n");
+
+ /* find base address: */
+ offset = CYCLONE_CBAR_ADDR;
+ reg = ioremap_nocache(offset, sizeof(reg));
+ if (!reg) {
+ printk(KERN_ERR "Summit chipset: Could not find valid CBAR register.\n");
+ return -ENODEV;
+ }
+ /* even on 64bit systems, this is only 32bits: */
+ base = readl(reg);
+ if (!base) {
+ printk(KERN_ERR "Summit chipset: Could not find valid CBAR value.\n");
+ return -ENODEV;
+ }
+ iounmap(reg);
+
+ /* setup PMCC: */
+ offset = base + CYCLONE_PMCC_OFFSET;
+ reg = ioremap_nocache(offset, sizeof(reg));
+ if (!reg) {
+ printk(KERN_ERR "Summit chipset: Could not find valid PMCC register.\n");
+ return -ENODEV;
+ }
+ writel(0x00000001,reg);
+ iounmap(reg);
+
+ /* setup MPCS: */
+ offset = base + CYCLONE_MPCS_OFFSET;
+ reg = ioremap_nocache(offset, sizeof(reg));
+ if (!reg) {
+ printk(KERN_ERR "Summit chipset: Could not find valid MPCS register.\n");
+ return -ENODEV;
+ }
+ writel(0x00000001,reg);
+ iounmap(reg);
+
+ /* map in cyclone_timer: */
+ offset = base + CYCLONE_MPMC_OFFSET;
+ cyclone_timer = ioremap_nocache(offset, sizeof(u64));
+ if (!cyclone_timer) {
+ printk(KERN_ERR "Summit chipset: Could not find valid MPMC register.\n");
+ return -ENODEV;
+ }
+
+ /* quick test to make sure its ticking: */
+ for (i = 0; i < 3; i++){
+ u32 old = readl(cyclone_timer);
+ int stall = 100;
+
+ while (stall--)
+ barrier();
+
+ if (readl(cyclone_timer) == old) {
+ printk(KERN_ERR "Summit chipset: Counter not counting! DISABLED\n");
+ iounmap(cyclone_timer);
+ cyclone_timer = NULL;
+ return -ENODEV;
+ }
+ }
+ cyclone_ptr = cyclone_timer;
+
+ /* sort out mult/shift values: */
+ clocksource_cyclone.shift = 22;
+ clocksource_cyclone.mult = clocksource_hz2mult(CYCLONE_TIMER_FREQ,
+ clocksource_cyclone.shift);
+
+ return register_clocksource(&clocksource_cyclone);
+}
+
+module_init(init_cyclone_clocksource);
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