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

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