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-rw-r--r--arch/ia64/kernel/cyclone.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/ia64/kernel/cyclone.c b/arch/ia64/kernel/cyclone.c
new file mode 100644
index 000000000..258d7b70c
--- /dev/null
+++ b/arch/ia64/kernel/cyclone.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/time.h>
+#include <linux/errno.h>
+#include <linux/timex.h>
+#include <linux/clocksource.h>
+#include <linux/io.h>
+
+/* IBM Summit (EXA) Cyclone counter code*/
+#define CYCLONE_CBAR_ADDR 0xFEB00CD0
+#define CYCLONE_PMCC_OFFSET 0x51A0
+#define CYCLONE_MPMC_OFFSET 0x51D0
+#define CYCLONE_MPCS_OFFSET 0x51A8
+#define CYCLONE_TIMER_FREQ 100000000
+
+int use_cyclone;
+void __init cyclone_setup(void)
+{
+ use_cyclone = 1;
+}
+
+static void __iomem *cyclone_mc;
+
+static u64 read_cyclone(struct clocksource *cs)
+{
+ return (u64)readq((void __iomem *)cyclone_mc);
+}
+
+static struct clocksource clocksource_cyclone = {
+ .name = "cyclone",
+ .rating = 300,
+ .read = read_cyclone,
+ .mask = (1LL << 40) - 1,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+int __init init_cyclone_clock(void)
+{
+ u64 __iomem *reg;
+ u64 base; /* saved cyclone base address */
+ u64 offset; /* offset from pageaddr to cyclone_timer register */
+ int i;
+ u32 __iomem *cyclone_timer; /* Cyclone MPMC0 register */
+
+ if (!use_cyclone)
+ return 0;
+
+ printk(KERN_INFO "Summit chipset: Starting Cyclone Counter.\n");
+
+ /* find base address */
+ offset = (CYCLONE_CBAR_ADDR);
+ reg = ioremap(offset, sizeof(u64));
+ if(!reg){
+ printk(KERN_ERR "Summit chipset: Could not find valid CBAR"
+ " register.\n");
+ use_cyclone = 0;
+ return -ENODEV;
+ }
+ base = readq(reg);
+ iounmap(reg);
+ if(!base){
+ printk(KERN_ERR "Summit chipset: Could not find valid CBAR"
+ " value.\n");
+ use_cyclone = 0;
+ return -ENODEV;
+ }
+
+ /* setup PMCC */
+ offset = (base + CYCLONE_PMCC_OFFSET);
+ reg = ioremap(offset, sizeof(u64));
+ if(!reg){
+ printk(KERN_ERR "Summit chipset: Could not find valid PMCC"
+ " register.\n");
+ use_cyclone = 0;
+ return -ENODEV;
+ }
+ writel(0x00000001,reg);
+ iounmap(reg);
+
+ /* setup MPCS */
+ offset = (base + CYCLONE_MPCS_OFFSET);
+ reg = ioremap(offset, sizeof(u64));
+ if(!reg){
+ printk(KERN_ERR "Summit chipset: Could not find valid MPCS"
+ " register.\n");
+ use_cyclone = 0;
+ return -ENODEV;
+ }
+ writel(0x00000001,reg);
+ iounmap(reg);
+
+ /* map in cyclone_timer */
+ offset = (base + CYCLONE_MPMC_OFFSET);
+ cyclone_timer = ioremap(offset, sizeof(u32));
+ if(!cyclone_timer){
+ printk(KERN_ERR "Summit chipset: Could not find valid MPMC"
+ " register.\n");
+ use_cyclone = 0;
+ 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;
+ use_cyclone = 0;
+ return -ENODEV;
+ }
+ }
+ /* initialize last tick */
+ cyclone_mc = cyclone_timer;
+ clocksource_cyclone.archdata.fsys_mmio = cyclone_timer;
+ clocksource_register_hz(&clocksource_cyclone, CYCLONE_TIMER_FREQ);
+
+ return 0;
+}
+
+__initcall(init_cyclone_clock);