LXR uboot/arch/arm/cpu/armv7/iproc-common/timer.c

   1/*
   2 * Copyright 2014 Broadcom Corporation.
   3 *
   4 * SPDX-License-Identifier:     GPL-2.0+
   5 */
   6
   7#include <common.h>
   8#include <div64.h>
   9#include <asm/io.h>
  10#include <asm/iproc-common/timer.h>
  11#include <asm/iproc-common/sysmap.h>
  12
  13static inline uint64_t timer_global_read(void)
  14{
  15        uint64_t cur_tick;
  16        uint32_t count_h;
  17        uint32_t count_l;
  18
  19        do {
  20                count_h = readl(IPROC_PERIPH_GLB_TIM_REG_BASE +
  21                                TIMER_GLB_HI_OFFSET);
  22                count_l = readl(IPROC_PERIPH_GLB_TIM_REG_BASE +
  23                                TIMER_GLB_LOW_OFFSET);
  24                cur_tick = readl(IPROC_PERIPH_GLB_TIM_REG_BASE +
  25                                 TIMER_GLB_HI_OFFSET);
  26        } while (cur_tick != count_h);
  27
  28        return (cur_tick << 32) + count_l;
  29}
  30
  31void timer_global_init(void)
  32{
  33        writel(0, IPROC_PERIPH_GLB_TIM_REG_BASE + TIMER_GLB_CTRL_OFFSET);
  34        writel(0, IPROC_PERIPH_GLB_TIM_REG_BASE + TIMER_GLB_LOW_OFFSET);
  35        writel(0, IPROC_PERIPH_GLB_TIM_REG_BASE + TIMER_GLB_HI_OFFSET);
  36        writel(TIMER_GLB_TIM_CTRL_TIM_EN,
  37               IPROC_PERIPH_GLB_TIM_REG_BASE + TIMER_GLB_CTRL_OFFSET);
  38}
  39
  40int timer_init(void)
  41{
  42        timer_global_init();
  43        return 0;
  44}
  45
  46unsigned long get_timer(unsigned long base)
  47{
  48        uint64_t count;
  49        uint64_t ret;
  50        uint64_t tim_clk;
  51        uint64_t periph_clk;
  52
  53        count = timer_global_read();
  54
  55        /* default arm clk is 1GHz, periph_clk=arm_clk/2, tick per msec */
  56        periph_clk = 500000;
  57        tim_clk = lldiv(periph_clk,
  58                        (((readl(IPROC_PERIPH_GLB_TIM_REG_BASE +
  59                                 TIMER_GLB_CTRL_OFFSET) &
  60                        TIMER_GLB_TIM_CTRL_PRESC_MASK) >> 8) + 1));
  61
  62        ret = lldiv(count, (uint32_t)tim_clk);
  63
  64        /* returns msec */
  65        return ret - base;
  66}
  67
  68void __udelay(unsigned long usec)
  69{
  70        uint64_t cur_tick, end_tick;
  71        uint64_t tim_clk;
  72        uint64_t periph_clk;
  73
  74        /* default arm clk is 1GHz, periph_clk=arm_clk/2, tick per usec */
  75        periph_clk = 500;
  76
  77        tim_clk = lldiv(periph_clk,
  78                        (((readl(IPROC_PERIPH_GLB_TIM_REG_BASE +
  79                                 TIMER_GLB_CTRL_OFFSET) &
  80                        TIMER_GLB_TIM_CTRL_PRESC_MASK) >> 8) + 1));
  81
  82        cur_tick = timer_global_read();
  83
  84        end_tick = tim_clk;
  85        end_tick *= usec;
  86        end_tick += cur_tick;
  87
  88        do {
  89                cur_tick = timer_global_read();
  90
  91        } while (cur_tick < end_tick);
  92}
  93
  94void timer_systick_init(uint32_t tick_ms)
  95{
  96        /* Disable timer and clear interrupt status*/
  97        writel(0, IPROC_PERIPH_PVT_TIM_REG_BASE + TIMER_PVT_CTRL_OFFSET);
  98        writel(TIMER_PVT_TIM_INT_STATUS_SET,
  99               IPROC_PERIPH_PVT_TIM_REG_BASE + TIMER_PVT_STATUS_OFFSET);
 100        writel((PLL_AXI_CLK/1000) * tick_ms,
 101               IPROC_PERIPH_PVT_TIM_REG_BASE + TIMER_PVT_LOAD_OFFSET);
 102        writel(TIMER_PVT_TIM_CTRL_INT_EN |
 103               TIMER_PVT_TIM_CTRL_AUTO_RELD |
 104               TIMER_PVT_TIM_CTRL_TIM_EN,
 105               IPROC_PERIPH_PVT_TIM_REG_BASE + TIMER_PVT_CTRL_OFFSET);
 106}
 107
 108void timer_systick_isr(void *data)
 109{
 110        writel(TIMER_PVT_TIM_INT_STATUS_SET,
 111               IPROC_PERIPH_PVT_TIM_REG_BASE + TIMER_PVT_STATUS_OFFSET);
 112}
 113
 114/*
 115 * This function is derived from PowerPC code (read timebase as long long).
 116 * On ARM it just returns the timer value in msec.
 117 */
 118unsigned long long get_ticks(void)
 119{
 120        return get_timer(0);
 121}
 122
 123/*
 124 * This is used in conjuction with get_ticks, which returns msec as ticks.
 125 * Here we just return ticks/sec = msec/sec = 1000
 126 */
 127ulong get_tbclk(void)
 128{
 129        return 1000;
 130}
 131