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-rw-r--r--arch/s390/include/asm/timex.h257
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h
new file mode 100644
index 000000000..99a7e0282
--- /dev/null
+++ b/arch/s390/include/asm/timex.h
@@ -0,0 +1,257 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * S390 version
+ * Copyright IBM Corp. 1999
+ *
+ * Derived from "include/asm-i386/timex.h"
+ * Copyright (C) 1992, Linus Torvalds
+ */
+
+#ifndef _ASM_S390_TIMEX_H
+#define _ASM_S390_TIMEX_H
+
+#include <linux/preempt.h>
+#include <linux/time64.h>
+#include <asm/lowcore.h>
+
+/* The value of the TOD clock for 1.1.1970. */
+#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
+
+extern u64 clock_comparator_max;
+
+/* Inline functions for clock register access. */
+static inline int set_tod_clock(__u64 time)
+{
+ int cc;
+
+ asm volatile(
+ " sck %1\n"
+ " ipm %0\n"
+ " srl %0,28\n"
+ : "=d" (cc) : "Q" (time) : "cc");
+ return cc;
+}
+
+static inline int store_tod_clock(__u64 *time)
+{
+ int cc;
+
+ asm volatile(
+ " stck %1\n"
+ " ipm %0\n"
+ " srl %0,28\n"
+ : "=d" (cc), "=Q" (*time) : : "cc");
+ return cc;
+}
+
+static inline void set_clock_comparator(__u64 time)
+{
+ asm volatile("sckc %0" : : "Q" (time));
+}
+
+static inline void store_clock_comparator(__u64 *time)
+{
+ asm volatile("stckc %0" : "=Q" (*time));
+}
+
+void clock_comparator_work(void);
+
+void __init time_early_init(void);
+
+extern unsigned char ptff_function_mask[16];
+
+/* Function codes for the ptff instruction. */
+#define PTFF_QAF 0x00 /* query available functions */
+#define PTFF_QTO 0x01 /* query tod offset */
+#define PTFF_QSI 0x02 /* query steering information */
+#define PTFF_QUI 0x04 /* query UTC information */
+#define PTFF_ATO 0x40 /* adjust tod offset */
+#define PTFF_STO 0x41 /* set tod offset */
+#define PTFF_SFS 0x42 /* set fine steering rate */
+#define PTFF_SGS 0x43 /* set gross steering rate */
+
+/* Query TOD offset result */
+struct ptff_qto {
+ unsigned long long physical_clock;
+ unsigned long long tod_offset;
+ unsigned long long logical_tod_offset;
+ unsigned long long tod_epoch_difference;
+} __packed;
+
+static inline int ptff_query(unsigned int nr)
+{
+ unsigned char *ptr;
+
+ ptr = ptff_function_mask + (nr >> 3);
+ return (*ptr & (0x80 >> (nr & 7))) != 0;
+}
+
+/* Query UTC information result */
+struct ptff_qui {
+ unsigned int tm : 2;
+ unsigned int ts : 2;
+ unsigned int : 28;
+ unsigned int pad_0x04;
+ unsigned long leap_event;
+ short old_leap;
+ short new_leap;
+ unsigned int pad_0x14;
+ unsigned long prt[5];
+ unsigned long cst[3];
+ unsigned int skew;
+ unsigned int pad_0x5c[41];
+} __packed;
+
+/*
+ * ptff - Perform timing facility function
+ * @ptff_block: Pointer to ptff parameter block
+ * @len: Length of parameter block
+ * @func: Function code
+ * Returns: Condition code (0 on success)
+ */
+#define ptff(ptff_block, len, func) \
+({ \
+ struct addrtype { char _[len]; }; \
+ register unsigned int reg0 asm("0") = func; \
+ register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\
+ int rc; \
+ \
+ asm volatile( \
+ " .word 0x0104\n" \
+ " ipm %0\n" \
+ " srl %0,28\n" \
+ : "=d" (rc), "+m" (*(struct addrtype *) reg1) \
+ : "d" (reg0), "d" (reg1) : "cc"); \
+ rc; \
+})
+
+static inline unsigned long long local_tick_disable(void)
+{
+ unsigned long long old;
+
+ old = S390_lowcore.clock_comparator;
+ S390_lowcore.clock_comparator = clock_comparator_max;
+ set_clock_comparator(S390_lowcore.clock_comparator);
+ return old;
+}
+
+static inline void local_tick_enable(unsigned long long comp)
+{
+ S390_lowcore.clock_comparator = comp;
+ set_clock_comparator(S390_lowcore.clock_comparator);
+}
+
+#define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
+#define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
+
+typedef unsigned long long cycles_t;
+
+static inline void get_tod_clock_ext(char *clk)
+{
+ typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
+
+ asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
+}
+
+static inline unsigned long long get_tod_clock(void)
+{
+ char clk[STORE_CLOCK_EXT_SIZE];
+
+ get_tod_clock_ext(clk);
+ return *((unsigned long long *)&clk[1]);
+}
+
+static inline unsigned long long get_tod_clock_fast(void)
+{
+#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
+ unsigned long long clk;
+
+ asm volatile("stckf %0" : "=Q" (clk) : : "cc");
+ return clk;
+#else
+ return get_tod_clock();
+#endif
+}
+
+static inline cycles_t get_cycles(void)
+{
+ return (cycles_t) get_tod_clock() >> 2;
+}
+#define get_cycles get_cycles
+
+int get_phys_clock(unsigned long *clock);
+void init_cpu_timer(void);
+unsigned long long monotonic_clock(void);
+
+extern unsigned char tod_clock_base[16] __aligned(8);
+
+/**
+ * get_clock_monotonic - returns current time in clock rate units
+ *
+ * The clock and tod_clock_base get changed via stop_machine.
+ * Therefore preemption must be disabled, otherwise the returned
+ * value is not guaranteed to be monotonic.
+ */
+static inline unsigned long long get_tod_clock_monotonic(void)
+{
+ unsigned long long tod;
+
+ preempt_disable_notrace();
+ tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1];
+ preempt_enable_notrace();
+ return tod;
+}
+
+/**
+ * tod_to_ns - convert a TOD format value to nanoseconds
+ * @todval: to be converted TOD format value
+ * Returns: number of nanoseconds that correspond to the TOD format value
+ *
+ * Converting a 64 Bit TOD format value to nanoseconds means that the value
+ * must be divided by 4.096. In order to achieve that we multiply with 125
+ * and divide by 512:
+ *
+ * ns = (todval * 125) >> 9;
+ *
+ * In order to avoid an overflow with the multiplication we can rewrite this.
+ * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits)
+ * we end up with
+ *
+ * ns = ((2^9 * th + tl) * 125 ) >> 9;
+ * -> ns = (th * 125) + ((tl * 125) >> 9);
+ *
+ */
+static inline unsigned long long tod_to_ns(unsigned long long todval)
+{
+ return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
+}
+
+/**
+ * tod_after - compare two 64 bit TOD values
+ * @a: first 64 bit TOD timestamp
+ * @b: second 64 bit TOD timestamp
+ *
+ * Returns: true if a is later than b
+ */
+static inline int tod_after(unsigned long long a, unsigned long long b)
+{
+ if (MACHINE_HAS_SCC)
+ return (long long) a > (long long) b;
+ return a > b;
+}
+
+/**
+ * tod_after_eq - compare two 64 bit TOD values
+ * @a: first 64 bit TOD timestamp
+ * @b: second 64 bit TOD timestamp
+ *
+ * Returns: true if a is later than b
+ */
+static inline int tod_after_eq(unsigned long long a, unsigned long long b)
+{
+ if (MACHINE_HAS_SCC)
+ return (long long) a >= (long long) b;
+ return a >= b;
+}
+
+#endif